JP2012128121A - Illumination device and projector - Google Patents

Abstract

Provided is an illumination device capable of suppressing a decrease in luminous efficiency of a fluorescent layer even when the output of an excitation light source device is increased.
An illumination device 101 according to the present invention includes a first light source device 10a that emits a first light La, a second light source device 10b that emits a second light Lb, a first light La, and A fluorescent layer 42 excited by the second light Lb;
At least part of the first light La and at least part of the second light Lb overlap each other on the fluorescent layer 42, and the light intensity of the beam spot of the first light La formed on the fluorescent layer 42 The first high-intensity region having the largest intensity and the second high-intensity region having the largest light intensity among the beam spots of the second light Lb formed on the phosphor layer 42 are separated from each other on the phosphor layer 42. The condensing optical system 20 that irradiates the fluorescent layer 42 with the first light La and the second light Lb is provided.
[Selection] Figure 1

Description

  The present invention relates to a lighting device and a projector.

  As a lighting device for a projector, a lighting device described in Patent Document 1 is known. The illumination device of Patent Document 1 includes a light source that emits excitation light (blue light), and a fluorescent plate that is formed by forming two types of fluorescent layers (a red fluorescent layer and a green fluorescent layer) on a disc that is rotated by a motor. It is equipped with. On the disk, three segment regions are formed along the rotation direction. Two of the three segment areas are formed with two types of fluorescent layers that emit different colored light (red light and green light), and the remaining segment areas scatter excitation light (blue light). A scatterer is formed. According to the illuminating device of patent document 1, the illuminating device which can radiate | emit three color lights sequentially using excitation light and two types of fluorescent layers can be provided.

JP 2009-277516 A

  In the illumination device of Patent Document 1, a laser light source is used as a light source device for excitation. In order to increase the light intensity of the emitted light (fluorescence) in the illumination device of Patent Document 1, a method of increasing the intensity of the excitation light by increasing the output of the laser light source can be considered. However, the higher the intensity of the excitation light that irradiates a small area of the fluorescent layer, the lower the luminous efficiency of the fluorescent layer. This is because the temperature of the part irradiated with the excitation light suddenly rises, and when the light density of the excitation light increases, the decrease in the number density of the absorption levels due to absorption of the excitation light cannot be ignored. It can be considered that the light absorption rate decreases. The former is called a temperature quenching phenomenon, and the latter is called a saturation excitation phenomenon. Therefore, even if the output of the laser light source is increased, the intensity of the emitted light cannot be increased as expected.

  SUMMARY An advantage of some aspects of the invention is that it provides an illumination device and a projector that can efficiently convert excitation light into fluorescence.

  In order to solve the above-described problems, an illumination device according to the present invention includes a first light source device that emits first light, a second light source device that emits second light, the first light, and the light source device. A fluorescent layer excited by second light, at least a part of the first light, and at least a part of the second light overlap each other on the fluorescent layer and are formed on the fluorescent layer. A first high intensity region having the highest light intensity among the first light beam spots and a second high intensity having the highest light intensity among the second light beam spots formed on the fluorescent layer. And a condensing optical system for irradiating the fluorescent layer with the first light and the second light so that an intensity region is spaced apart from the fluorescent layer. Features.

  According to this configuration, since the first light and the second light are irradiated to the fluorescent layer while shifting the center of each other, it is possible to suppress the occurrence of a protruding portion having a high light intensity on the fluorescent layer. The Therefore, a decrease in luminous efficiency that occurs when the output of the excitation light source device is increased is suppressed, and a bright illumination device is provided.

  The beam spot of the first light formed on the fluorescent layer includes a first attenuation region where the light intensity gradually attenuates at the periphery of the first high-intensity region, and is formed on the fluorescent layer. The second light beam spot includes a second attenuation region in which the light intensity gradually attenuates in the periphery of the second high-intensity region, and the condensing optical system is disposed on the fluorescent layer. The first light so that the first attenuation region and the second high-intensity region do not overlap with each other and the first high-intensity region and the second attenuation region do not overlap with each other. It is desirable to irradiate the fluorescent layer with the second light.

  According to this configuration, the light intensity distribution on the fluorescent layer is made more uniform. Therefore, it becomes easier to suppress a decrease in luminous efficiency.

  The beam spot of the first light formed on the fluorescent layer includes a first attenuation region where the light intensity gradually attenuates at the periphery of the first high-intensity region, and is formed on the fluorescent layer. The second light beam spot includes a second attenuation region in which the light intensity gradually attenuates in a peripheral portion of the second high intensity region, and the condensing optical system is arranged on the fluorescent layer. On a straight line including the first high intensity region and the second high intensity region, a region where the light intensity of the first light is ½ of the light intensity in the first high intensity region; and Irradiating the fluorescent layer with the first light and the second light so that a region where the light intensity of the second light is ½ of the light intensity in the second high-intensity region overlap each other. It is desirable to do.

  According to this configuration, it is possible to suppress a decrease in the light intensity of the excitation light in a region between the first high intensity region and the second high intensity region. Therefore, the light intensity distribution on the fluorescent layer is made more uniform, and the decrease in light emission efficiency is more easily suppressed.

  The fluorescent layer is preferably formed continuously on a plate material rotated by a motor along the rotation direction of the plate material.

  According to this configuration, the heat of the fluorescent layer generated by the excitation light irradiation can be dissipated in a wide region along the rotation direction of the plate material. Therefore, a decrease in luminous efficiency that occurs when the output of the excitation light source device is increased is suppressed, and a bright illumination device is provided.

  The light source device is preferably a laser light source that emits laser light as the excitation light.

  According to this configuration, since the highly condensing laser light source is used as the light source device, the fluorescent layer can emit light in a small area. Therefore, the luminous efficiency of the fluorescent layer can be increased, and a bright illumination device is provided.

  The projector according to the present invention includes the illumination device according to the present invention, a light modulation device that modulates illumination light from the illumination device according to image information, and a projection optical system that projects the modulated light from the light modulation device as a projection image. And.

  According to this configuration, a projector capable of displaying a bright projection image is provided.

FIG. 2 is a top view showing an optical system of the projector according to the first embodiment. It is a graph which shows the light emission characteristic of the light source device of 1st Embodiment, and a fluorescent layer. It is explanatory drawing of the rotation fluorescent screen of 1st Embodiment. It is a figure which shows the beam spot of the some excitation light irradiated on a fluorescent layer. It is a top view which shows the optical system of the projector of 2nd Embodiment. It is a graph which shows the light emission characteristic of a 2nd light source device. It is a top view which shows the optical system of the projector of 3rd Embodiment. It is explanatory drawing of the rotation fluorescent screen of 3rd Embodiment. It is a top view which shows the optical system of the projector of 4th Embodiment. It is an example of arrangement | positioning of the beam spot of the projector of 5th Embodiment. It is an example of arrangement | positioning of the beam spot of the projector of 5th Embodiment. It is a figure which shows the other example of arrangement | positioning of the beam spot of the some excitation light irradiated on a fluorescent layer.

[First embodiment]
FIG. 1 is a top view showing an optical system of the projector 1001 according to the first embodiment. FIG. 2 is a graph showing the light emission characteristics of the light source device 10 and the fluorescent layer 42 provided in the projector 1001. FIG. 2A is a graph showing the light emission characteristics of the light source device 10, and FIG. 2B is a graph showing the light emission characteristics of the fluorescent layer 42. The light emission characteristic is a characteristic of what wavelength of light is emitted with what intensity when a voltage is applied in a light source device and when excitation light is incident in a fluorescent layer. . The vertical axis of the graph represents the relative light emission intensity, and the light emission intensity at the wavelength with the highest light emission intensity is 1. The horizontal axis of the graph represents the wavelength. FIG. 3 is an explanatory diagram of the rotating fluorescent plate 30 provided in the projector 1001. 3A is a front view of the rotating fluorescent plate 30, and FIG. 3B is a cross-sectional view taken along line A1-A1 of FIG. FIG. 4 is a diagram showing a beam spot on the fluorescent layer of excitation light irradiated on the fluorescent layer. FIG. 4A is a plan view of the beam spot BS of the excitation light irradiated on the fluorescent layer on the fluorescent layer, and FIG. 4B is a diagram showing the light intensity distribution of the excitation light.

  As shown in FIG. 1, the projector 1001 includes an illumination device 101, a color separation light guide optical system 200, a liquid crystal light modulation device 400R as a light modulation device, a liquid crystal light modulation device 400G, a liquid crystal light modulation device 400B, and a cross dichroic prism 500. And a projection optical system 600.

  The illumination device 101 includes a light source device 10a, a light source device 10b, a light source device 10c, a condensing optical system 20, a rotating fluorescent plate 30, a motor 50, a collimating optical system 60, a first lens array 120, a second lens array 130, and a polarization conversion element. 140 and a superimposing lens 150 are provided.

  Each of the light source device 10a, the light source device 10b, and the light source device 10c is a laser light source that emits blue laser light (emission intensity peak: about 445 nm, see FIG. 2A). In this specification, the light source device 10a, the light source device 10b, and the light source device 10c may be collectively referred to as the light source device 10, and the laser light La emitted from the light source device 10a and the laser light Lb emitted from the light source device 10b. And the laser beam Lc emitted from the light source device 10c may be collectively referred to as a laser beam L. In the present embodiment, for example, the light source device 10a corresponds to the first light source device, the light source device 10b corresponds to the second light source device, the laser light La corresponds to the first light, and the laser light Lb corresponds to the first light source device. It corresponds to the second light.

  In FIG. 2A, the symbol B is a color light component of the laser light L emitted from the light source device 10. The illumination device 101 illustrated in FIG. 1 includes three light source devices 10 (light source device 10a, light source device 10b, and light source device 10c), but the number of light source devices 10 is not limited to this, and two or four or more. But you can. A light source device that emits blue light having a wavelength other than 445 nm (for example, 460 nm) as excitation light can also be used. As will be described later, the laser light La emitted from the light source device 10a, the laser light Lb emitted from the light source device 10b, and the laser light Lc emitted from the light source device 10c are formed on the fluorescent layer 42 by the condensing optical system 20. Are partially overlapped with each other to form excitation light that excites the fluorescent layer 42.

  The condensing optical system 20 includes a plurality of first lenses 22 and a second lens 24. The condensing optical system 20 is disposed in the optical path from the light source device 10 to the rotating fluorescent plate 30 and causes the laser light La, the laser light Lb, and the laser light Lc to enter the fluorescent layer 42 in a substantially condensed state. The first lens 22 is a collimating lens, and the second lens 24 is a condenser lens. The first lens 22 and the second lens 24 are, for example, convex lenses.

  The rotating fluorescent plate 30 is a so-called transmission type rotating fluorescent plate. As shown in FIGS. 1 and 3, the rotating fluorescent plate 30 is formed by continuously forming a single fluorescent layer 42 along the rotation direction of the plate 40 on a part of the plate 40 that can be rotated by the motor 50. . The region where the fluorescent layer 42 is formed includes a region where excitation light is incident. The rotating fluorescent plate 30 emits red light and green light toward the side opposite to the side on which excitation light (blue light) is incident.

  The rotating fluorescent plate 30 rotates at 7500 rpm when in use. Although the detailed description is omitted, the diameter of the rotating fluorescent plate 30 is 50 mm, and the optical axis of the excitation light incident on the rotating fluorescent plate 30 is located at a position about 22.5 mm away from the rotation center of the rotating fluorescent plate 30. ing. That is, the rotating fluorescent plate 30 rotates at such a rotational speed that the condensed spot of the excitation light moves on the fluorescent layer 42 at about 18 m / sec.

  The plate member 40 is made of a material that transmits excitation light. In FIG. 3, the plate member 40 is a disc, but the plate member 40 is not limited to a disc. As a material of the plate member 40, for example, quartz glass, crystal, sapphire, optical glass, transparent resin, or the like can be used. The laser light L emitted from the light source device 10 enters the rotating fluorescent plate 30 from the plate material 40 side as excitation light.

  The fluorescent layer 42 is formed on the plate member 40 via a dichroic film 44 that transmits excitation light and reflects fluorescence emitted from the fluorescent layer 42. The dichroic film 44 is made of, for example, a dielectric multilayer film.

  The fluorescent layer 42 converts, for example, a part of the laser light L (blue light) as excitation light emitted from the light source device 10 into light including red light and green light, and the excitation light (blue light). Let the rest pass through without conversion. Specifically, the fluorescent layer 42 is efficiently excited by excitation light having a wavelength of 445 nm, and a part of the excitation light emitted from the light source device 10 is converted into red light and green light as shown in FIG. It is converted into yellow fluorescence containing light and emitted. Of the yellow fluorescence, the short wavelength component is used as green light, and among the yellow fluorescence, the long wavelength component is used as red light.

The fluorescent layer 42 is made of, for example, a layer containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, which is a YAG phosphor. As the fluorescent layer 42, a layer containing another phosphor that emits fluorescence including red light and green light may be used. Further, as the fluorescent layer 42, a layer containing a mixture of a phosphor that converts excitation light (blue light) into red light and a phosphor that converts excitation light (blue light) into green light may be used.

  The light intensity distribution of the laser light used in this embodiment has a Gaussian distribution. In a plane perpendicular to the optical axis of the laser beam, the portion close to the central axis of the laser beam L is the high-intensity region C having the highest light intensity, and the periphery of the high-intensity region C is an attenuation in which the light intensity gradually attenuates. Region D.

  A beam spot BS formed on the fluorescent layer 42 by the excitation light irradiated on the fluorescent layer 42 is indicated by a solid line in FIG.

  The beam spot formed on the fluorescent layer 42 by the laser light La emitted from the light source device 10a has a circular shape centered on the highest high-intensity region Ca, as shown by the solid line and the broken line. ing. Similarly, the beam spot of the laser beam Lb emitted from the light source device 10b has a circular shape centering on the highest high-intensity region Cb, and the beam spot of the laser beam Lc emitted from the light source device 10c is the highest. It has a circular shape centered on the high-strength region Cc.

  In the present invention, for example, the high intensity region Ca of the laser beam La corresponds to a first high intensity region, the high intensity region Cb of the laser beam Lb corresponds to a second high intensity region, and the attenuation region of the laser beam La. Da corresponds to the first attenuation region, and the attenuation region Db of the laser light La corresponds to the second attenuation region.

  The light intensity distribution of the excitation light on the straight line K including the highest high-intensity region Ca of the laser light La and the highest high-intensity region Cb of the laser light Lb on the fluorescent layer 42 is shown by a solid line in FIG. .

  The light intensity distribution of the laser light La on the straight line K on the fluorescent layer 42 has a distribution centered on the high-intensity region Ca, as shown by using a solid line and a broken line. Similarly, the light intensity distribution of the laser beam Lb has a distribution centered on the high intensity region Cb, and the light intensity distribution of the laser beam Lc has a distribution centered on the high intensity region Cc.

  As shown in FIG. 4A, the laser light La emitted from the light source device 10a is condensed on the fluorescent layer 42 via the first lens 22a and the second lens 24, and emitted from the light source device 10b. The laser light Lb is condensed on the fluorescent layer 42 via the first lens 22b and the second lens 24, and the laser light Lc emitted from the light source device 10c is transmitted via the first lens 22c and the second lens 24. And condensed on the fluorescent layer 42.

  Specifically, the laser beam La and the laser beam Lb that are adjacent to each other are such that, on the fluorescent layer 42, the attenuation region Da of the laser beam La and the attenuation region Db of the laser beam Lb partially overlap each other, and the laser beam The high intensity area | region Ca of La and the high intensity | strength area | region Cb of the laser beam Lb are condensed on the fluorescent layer 42 so that it may not mutually overlap. Similarly, on the fluorescent layer 42, the attenuation region Db of the laser beam Lb and the attenuation region Dc of the laser beam Lc partially overlap each other, and the high intensity region Cb of the laser beam Lb and the high intensity region of the laser beam Lc. Cc does not overlap with each other.

  Further, on the fluorescent layer 42, an interval H between the two high-intensity regions C adjacent to each other, for example, an interval H between the high-intensity region Ca of the laser beam La and the high-intensity region Cb of the laser beam Lb is It is larger than the radius S of the spot of the laser beam. Further, the high intensity region Ca of the laser beam La does not overlap with either the attenuation region Db or the high intensity region Cb of the laser beam Lb.

  When the high-intensity region Ca of the laser light La is superimposed on the high-intensity region Cb of the laser light Lb on the fluorescent layer 42, the light intensity of the region with the highest light intensity in the beam spot formed on the fluorescent layer 42 is the laser intensity. This is the sum of the light intensity of the light La in the high intensity region Ca and the light intensity of the laser light Lb in the high intensity region Cb, and very small light is irradiated to one small area of the fluorescent layer 42. As a result, the luminous efficiency of the fluorescent layer is reduced by the temperature quenching phenomenon and the saturation excitation phenomenon. Further, even when only one light source device is used and the output of the light source device is increased, a very small light is irradiated to a small area of the fluorescent layer 42, so that the luminous efficiency of the fluorescent layer is lowered. To do. However, according to the present invention, as can be seen from FIG. 4, for example, when excitation light is formed using two light source devices 10, the maximum light intensity at the beam spot BS of excitation light formed on the fluorescent layer 42. The value is smaller than twice the maximum value of the light intensity of the laser light emitted from one light source device 10. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 42, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency.

  However, it is not essential that the high-intensity region Ca of the laser beam La does not overlap with the attenuation region Db of the laser beam Lb. The high-intensity region of the laser light La so that the attenuation region Da of the laser light La and the attenuation region Db of the laser light Lb overlap each other on the fluorescent layer 42 and the beam spots of the laser beams adjacent to each other do not overlap each other. It suffices that Ca and the high-intensity region Cb of the laser beam Lb are separated from each other (so as not to overlap each other) on the fluorescent layer 42. In general, since the light intensity at the center of the beam spot of the laser beam is the strongest, the center of the beam spot of the laser beam La and the center of the beam spot of the laser beam Lb are arranged apart from each other on the fluorescent layer 42. Just do it. Further, when the attenuation region Da of the laser light La and the attenuation region Db of the laser light Lb are overlapped with each other on the fluorescent layer 42, the area of the light emitting region in the fluorescent layer 42 can be reduced. Therefore, increase in etendue can be suppressed and fluorescence can be used efficiently.

  The relative positional relationship between the laser beam Lb and the laser beam Lc is the same as the above-described relative positional relationship between the laser beam La and the laser beam Lb. The interval H between the high-intensity regions C of two adjacent laser beams is controlled by adjusting the arrangement of the light source device 10, the first lens 22, and the second lens 24, for example.

  In the example of FIG. 4, the example in which the laser light L has a light intensity distribution having a Gaussian distribution is shown, but the same applies to the case where the laser light L having a light intensity distribution other than the Gaussian distribution is used. The laser beam La, the laser beam Lb, and the laser beam Lc are made to be a fluorescent layer so that the two laser beam attenuation regions D that are adjacent to each other are overlapped and the high-intensity regions C that are adjacent to each other are not overlapped. 42 is condensed. In this way, in the light intensity distribution on the fluorescent layer 42 of the excitation light irradiated to the fluorescent layer 42, the occurrence of a portion having a large light intensity that protrudes is suppressed. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 42, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency, and as a result, a bright illumination device 101 is provided.

  Returning to FIG. 1, the collimating optical system 60 includes a first lens 62 that suppresses the spread of light from the rotating fluorescent plate 30, and a second lens 64 that substantially collimates the light incident from the first lens 62. Yes. The collimating optical system 60 has a function of making the light from the rotating fluorescent plate 30 substantially parallel as a whole. The second lens 62 and the second lens 64 are, for example, convex lenses.

  The first lens array 120 has a plurality of first small lenses 122 for dividing the light from the collimating optical system 60 into a plurality of partial light beams. The first lens array 120 functions as a light beam splitting optical element that splits light from the collimating optical system 60 into a plurality of partial light beams. The first lens array 120 has a configuration in which a plurality of first small lenses 122 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis 101ax. Although not illustrated, the outer shape of the first small lens 122 is substantially similar to the outer shapes of the image forming regions of the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B.

  The second lens array 130 has a plurality of second small lenses 132 corresponding to the plurality of first small lenses 122 of the first lens array 120. The second lens array 130, together with the superimposing lens 150, causes the images of the first small lenses 122 of the first lens array 120 to be in the vicinity of the image forming areas of the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B. It has a function to form an image. The second lens array 130 has a configuration in which a plurality of second small lenses 132 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis 101ax.

  The polarization conversion element 140 is an optical element that emits each partial light divided by the first lens array 120 as approximately one type of linearly polarized light having a uniform polarization direction. The polarization conversion element 140 transmits one linear polarization component of the polarization components included in the light from the rotating fluorescent plate 30 as it is, and reflects the other linear polarization component in a direction perpendicular to the illumination optical axis 101ax. A reflection layer that reflects the other linearly polarized light component reflected by the polarization separation layer in a direction parallel to the illumination optical axis 101ax, and a position that converts the other linearly polarized light component reflected by the reflective layer into one linearly polarized light component. A phase difference plate.

  The superimposing lens 150 is an optical element that condenses each partial light beam from the polarization conversion element 140 and superimposes it in the vicinity of the image forming region of the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B. . The superimposing lens 150 is arranged so that the optical axis of the superimposing lens 150 and the optical axis of the illumination device 101 substantially coincide. The superimposing lens 150 may be composed of a compound lens obtained by combining a plurality of lenses. The first lens array 120, the second lens array 130, and the superimposing lens 150 constitute an integrator optical system that makes the in-plane light intensity distribution of the light from the rotating fluorescent plate 30 uniform.

  Instead of the lens integrator optical system using the first lens array 120 and the second lens array 130, a rod integrator optical system using a rod lens may be used.

  The color separation light guide optical system 200 includes dichroic mirrors 210 and 220, reflection mirrors 230, 240 and 250, and relay lenses 260 and 270. The color separation light guide optical system 200 separates the light from the illumination device 101 into red light, green light, and blue light, and the respective color lights of red light, green light, and blue light are liquid crystal light modulation devices 400R to be illuminated. The liquid crystal light modulation device 400G and the liquid crystal light modulation device 400B have a function of guiding light. A condensing lens 300R, a condensing lens 300G, and a condensing lens 300B are disposed between the color separation light guide optical system 200 and the liquid crystal light modulation devices 400R, 400G, and 40B.

  The dichroic mirrors 210 and 220 are mirrors in which a wavelength selective transmission film that reflects light in a predetermined wavelength region and passes light in other wavelength regions is formed on a substrate. The dichroic mirror 210 is a dichroic mirror that transmits a red light component and reflects a green light component and a blue light component. The dichroic mirror 220 is a dichroic mirror that reflects a green component and transmits a blue light component. The reflection mirror 230 is a mirror that reflects a red light component. The reflection mirrors 240 and 250 are mirrors that reflect blue light components.

  The red light that has passed through the dichroic mirror 210 is reflected by the reflecting mirror 230, passes through the condenser lens 300R, and enters the image forming area of the liquid crystal light modulation device 400R for red light. The green light reflected by the dichroic mirror 210 is further reflected by the dichroic mirror 220, passes through the condenser lens 300G, and enters the image forming area of the green light liquid crystal light modulation device 400G. The blue light that has passed through the dichroic mirror 220 passes through the relay lens 260, the incident-side reflecting mirror 240, the relay lens 270, the exit-side reflecting mirror 250, and the condensing lens 300B to form an image of the liquid crystal light modulation device 400B for blue light. Incident into the area. The relay lenses 260 and 270 and the reflection mirrors 240 and 250 function as a relay optical system that guides the blue light component that has passed through the dichroic mirror 220 to the liquid crystal light modulation device 400B.

  The liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B modulate incident color light according to image information to form a color image. The liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B are illumination targets of the illumination device 101. Although not shown, an incident-side polarizing plate is disposed between each condenser lens 300R, 300G, 3000B and each liquid crystal light modulator 400R, liquid crystal light modulator 400G, and liquid crystal light modulator 400B. Between the light modulation device 400R, the liquid crystal light modulation device 400G, the liquid crystal light modulation device 400B, and the cross dichroic prism 500, an exit side polarizing plate is disposed. The incident side polarizing plate, the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, the liquid crystal light modulation device 400B, and the emission side polarizing plate modulate the light of each incident color light.

  The liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B are transmissive liquid crystal light modulation devices in which liquid crystal that is an electro-optical material is hermetically sealed between a pair of transparent glass substrates. The liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B include, for example, a polysilicon TFT as a switching element, and one type of straight line emitted from the incident-side polarizing plate according to a given image signal. Modulates the polarization direction of polarized light.

  The cross dichroic prism 500 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from the emission side polarizing plate. The cross dichroic prism 500 has a substantially square shape in plan view in which four right-angle prisms are bonded together. A dielectric multilayer film is formed on the substantially X-shaped interface where the right-angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces is a dielectric multilayer film that transmits green light and blue light and reflects red light, and the dielectric multilayer film formed at the other interface is A dielectric multilayer film that transmits red light and green light and reflects blue light. The red light and the blue light are bent by the two types of dielectric multilayer films formed on the substantially X-shaped interface, and the three color lights are synthesized by aligning with the traveling direction of the green light.

  The color image emitted from the cross dichroic prism 500 is enlarged and projected by the projection optical system 600 to form an image on the screen SCR.

  According to the projector 1001 having the above-described configuration, the fluorescent layer 42 is excited by the excitation light emitted from the light source device 10, and a plurality of color lights are emitted. Therefore, a plurality of color lights can be obtained while using the single color light source device 10.

  Since the fluorescent layer 42 is formed on the plate member 40 rotated by the motor 50, the heat of the fluorescent layer 42 generated by the excitation light irradiation is dissipated in a wide region along the rotation direction of the plate member 40. Therefore, a decrease in luminous efficiency due to heat generation of the fluorescent layer 42 is suppressed, and a brighter illumination device 101 is provided.

[Second Embodiment]
FIG. 5 is a top view showing the optical system of the projector 1002 of the second embodiment. FIG. 6 is a graph showing the light emission characteristics of the second light source device 710 provided in the projector 1002. The vertical axis of the graph represents the relative light emission intensity, and the light emission intensity at the wavelength with the highest light emission intensity is 1. The horizontal axis of the graph represents the wavelength. In FIG. 5, the same reference numerals are given to components common to the projector 1001 of the first embodiment, and detailed description thereof is omitted. These components will be described with reference to FIGS. 2, 3 and 4 as necessary.

  As shown in FIG. 5, the projector 1002 includes an illumination device 102, a second illumination device 700, a color separation light guide optical system 202, a liquid crystal light modulation device 400R as a light modulation device, a liquid crystal light modulation device 400G, and a liquid crystal light modulation device. 400B, a cross dichroic prism 500, and a projection optical system 600 are provided.

  In the projector 1001 of the first embodiment, a part of the blue light emitted from the light source device 10 is transmitted through the fluorescent layer and used as illumination light for the liquid crystal light modulation device 400B. On the other hand, in the projector 1002 according to the second embodiment, all of the blue light emitted from the light source device 10 is used as the excitation light for the fluorescent layer 46, and the blue light used as the illumination light for the liquid crystal light modulation device 400B is The light is emitted from a second lighting device 700 provided separately from the lighting device 102.

  The illumination device 102 includes a plurality of light source devices 10 (a light source device 10a, a light source device 10b, and a light source device 10c), a condensing optical system 20, a rotating fluorescent plate 32, a motor 50, a collimating optical system 60, a first lens array 120, a second A lens array 130, a polarization conversion element 140, and a superimposing lens 150 are provided. The configurations of the light source device 10, the condensing optical system 20, the motor 50, the collimating optical system 60, the first lens array 120, the second lens array 130, the polarization conversion element 140, and the superimposing lens 150 are the same as those in the first embodiment.

  The rotating fluorescent plate 32 is a so-called transmission type rotating fluorescent plate. The rotating fluorescent plate 32 is formed by continuously forming a single fluorescent layer 46 along the rotation direction of the plate 40 on a part of the plate 40 that can be rotated by the motor 50. The region where the fluorescent layer 46 is formed includes a region where excitation light is incident. The rotating fluorescent plate 32 emits red light and green light toward the side opposite to the side on which excitation light (blue light) is incident.

  The rotating fluorescent plate 32 rotates at 7500 rpm during use. Although a detailed description is omitted, the diameter of the rotating fluorescent plate 32 is 50 mm, and the optical axis of the excitation light incident on the rotating fluorescent plate 32 is located at a position about 22.5 mm away from the rotation center of the rotating fluorescent plate 32. ing. That is, the rotating fluorescent plate 32 rotates at such a rotational speed that the excitation light condensing spot moves on the fluorescent layer 46 at about 18 m / sec.

  The fluorescent layer 46 is formed on the plate member 40 via a dichroic film 44 that transmits excitation light and reflects fluorescence emitted from the fluorescent layer 46. The dichroic film 44 is made of, for example, a dielectric multilayer film.

  For example, the fluorescent layer 46 converts substantially all of the laser light L (blue light) as excitation light emitted from the light source device 10 into light including red light and green light. The fluorescent layer 46 is formed thicker than the fluorescent layer 42 of the first embodiment, and there is almost no excitation light that passes through the fluorescent layer 46 as it is. The fluorescent layer 46 is efficiently excited by excitation light having a wavelength of 445 nm, and the excitation light emitted from the light source device 10 is converted into yellow fluorescence including red light and green light, as shown in FIG. And inject. Of the yellow fluorescence, the short wavelength component is used as green light, and among the yellow fluorescence, the long wavelength component is used as red light.

The fluorescent layer 46 is made of a layer containing (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce, which is a YAG phosphor, for example. As the fluorescent layer 46, a layer containing another phosphor that emits fluorescence including red light and green light may be used. Further, as the fluorescent layer 46, a layer containing a mixture of a phosphor that converts excitation light (blue light) into red light and a phosphor that converts excitation light (blue light) into green light may be used.

  The laser light La emitted from the light source device 10a is condensed on the fluorescent layer 46 via the first lens 22a and the second lens 24, and the laser light Lb emitted from the light source device 10b is reflected on the first lens 22b and The laser light Lc condensed on the fluorescent layer 46 via the second lens 24 and emitted from the light source device 10 c is condensed on the fluorescent layer 46 via the first lens 22 c and the second lens 24. The laser light La, the laser light Lb, and the laser light Lc are superimposed on each other on the fluorescent layer 46 by the condensing optical system 20, thereby forming excitation light that excites the fluorescent layer 46. As shown in FIG. 4, on the fluorescent layer 46, the attenuation regions D of two adjacent laser beams partially overlap each other, and the light intensity of the two adjacent laser beams is the highest. Laser light La, laser light Lb, and laser light Lc are collected on the fluorescent layer 46 so that the high-intensity regions C do not overlap each other. Therefore, it is possible to suppress the occurrence of a portion having a large light intensity protruding in the light intensity distribution of the excitation light on the fluorescent layer 46. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 46, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency, and as a result, a bright illumination device 102 is provided.

  The second illumination device 700 includes a second light source device 710, a condensing optical system 720, a scattering plate 730, a polarization conversion integrator rod 740, and a condensing lens 750.

  The second light source device 710 is a laser light source that emits blue light (peak of emission intensity: about 445 nm, see FIG. 6) composed of laser light as color light. In FIG. 6, reference numeral B indicates a color light component emitted by the second light source device 710 as blue light. Although one light source device 710 is illustrated in FIG. 5, the number of light source devices 710 is not limited to this, and a plurality of light source devices 710 may be used. A light source device that emits blue light having a wavelength other than 445 nm (for example, 460 nm) can also be used.

  The condensing optical system 720 includes a first lens 722 and a second lens 724. As a whole, the condensing optical system 720 causes blue light to be incident on the scattering plate 730 in a substantially condensed state. The first lens 722 and the second lens 724 are, for example, convex lenses.

  The scattering plate 730 scatters the blue light from the second light source device 710 with a predetermined degree of scattering to obtain blue light having a light distribution similar to fluorescence (red light and green light emitted from the rotating fluorescent plate 33). . As the scattering plate 730, for example, polished glass made of optical glass can be used.

  The polarization conversion integrator rod 740 is an optical element that makes the in-plane light intensity distribution of the blue light from the second light source device 710 uniform and makes the blue light approximately one type of linearly polarized light with the same polarization direction. . The polarization conversion integrator rod 740 is not described in detail, but the integrator rod, the reflector disposed on the incident surface side of the integrator rod and having a small hole for blue light incidence, and the reflection disposed on the exit surface side. A type polarizing plate.

  A lens integrator optical system using a lens array and a polarization conversion element can also be used instead of the polarization conversion integrator rod using a rod lens.

  The condensing lens 750 condenses the light from the polarization conversion integrator rod 740 and causes it to enter the vicinity of the image forming area of the liquid crystal light modulator 400B.

  The color separation light guide optical system 202 includes a dichroic mirror 210, a reflection mirror 222, a reflection mirror 230, and a reflection mirror 250. The color separation light guide optical system 202 separates light from the illumination device 102 into red light and green light, and each of red light and green light from the illumination device 102 and blue light from the second illumination device 700. The color light is guided to the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 400B to be illuminated. A condensing lens 300R, a condensing lens 300G, and a condensing lens 300B are disposed between the color separation light guide optical system 200 and the liquid crystal light modulation device 400R, the liquid crystal light modulation device 400G, and the liquid crystal light modulation device 40B. .

  The red light that has passed through the dichroic mirror 210 is reflected by the reflecting mirror 230, passes through the condenser lens 300R, and enters the image forming area of the liquid crystal light modulation device 400R for red light. The green light reflected by the dichroic mirror 210 is further reflected by the reflection mirror 222, passes through the condenser lens 300G, and enters the image forming region of the green light liquid crystal light modulation device 400G. The blue light from the second illumination device 700 is reflected by the reflection mirror 250, passes through the condenser lens 300B, and enters the image forming region of the liquid crystal light modulation device 400B for blue light.

  According to the projector 1002 having the above configuration, the fluorescent layer 46 is excited by the excitation light emitted from the light source device 10, and a plurality of color lights are emitted. Therefore, a plurality of color lights can be obtained while using the single color light source device 10.

  Since the fluorescent layer 46 is formed on the plate member 40 rotated by the motor 50, the heat of the fluorescent layer 46 generated by the irradiation of the excitation light is dissipated in a wide region along the rotation direction of the plate member 40. Therefore, a decrease in light emission efficiency that occurs when the output of the excitation light source device is increased is suppressed, and a brighter illumination device 102 is provided.

[Third Embodiment]
FIG. 7 is a top view showing an optical system of the projector 1003 of the third embodiment. FIG. 8 is an explanatory diagram of the rotating fluorescent plate 33 provided in the projector 1003. FIG. 8A is a front view of the rotating fluorescent plate 33, and FIG. 8B is a cross-sectional view taken along line A2-A2 of FIG. In FIG. 7, components common to the projector 1002 of the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. These components will be described with reference to FIGS. 2, 3 and 4 as necessary.

  The projector 1003 is different from the projector 1002 of the second embodiment in the configuration of the illumination device 103. The configurations of the second illumination device 700, the color separation light guide optical system 202, the liquid crystal light modulation device 400R as a light modulation device, the liquid crystal light modulation device 400G, the liquid crystal light modulation device 400B, the cross dichroic prism 500, and the projection optical system 600 are the first. This is the same as the projector 1002 of the second embodiment.

  The illumination device 103 includes a plurality of light source devices 10 (light source device 10a, light source device 10b, and light source device 10c), a condensing optical system 70, a dichroic mirror 80, a rotating fluorescent plate 33, a motor 50, a first lens array 120, and a second lens. An array 130, a polarization conversion element 140, and a superimposing lens 150 are provided. The configurations of the light source device 10, the motor 50, the first lens array 120, the second lens array 130, the polarization conversion element 140, and the superimposing lens 150 are the same as those in the second embodiment.

  The optical axis of the light source device 10 is disposed so as to be orthogonal to the illumination optical axis 103ax. The condensing optical system 70 includes a first lens 72a, a first lens 72b, a first lens 72c, a second lens 74, a collimating optical system 60a, and a collimating optical system 60b.

  The collimating optical system 60a includes a first lens 62a that suppresses the spread of the laser light L emitted from the light source device 10, and a second lens 64a that substantially parallelizes the light incident from the first lens 62a. The collimating optical system 60b includes a first lens 62b that suppresses the spread of light from the rotating fluorescent plate 30 and a second lens 64b that substantially collimates the light incident from the first lens 62b.

  The collimating optical system 60 a is disposed in the optical path between the second lens 74 and the dichroic mirror 80. The collimating optical system 60 b is disposed in the optical path between the rotating fluorescent plate 30 and the dichroic mirror 80.

  The laser light La emitted from the light source device 10a, the laser light Lb emitted from the light source device 10b, and the laser light Lc emitted from the light source device 10c are fluorescent in a substantially condensed state via the condensing optical system 70. Incident on layer 46. The laser light La, the laser light Lb, and the laser light Lc are superimposed on each other on the fluorescent layer 42, whereby excitation light that excites the fluorescent layer 42 is formed. In the present specification, the first lens 72a, the first lens 72b, and the first lens 72c may be collectively referred to as the first lens 72. The first lens 72 is a collimating lens, and the second lens 74 is a condenser lens. The first lens 72 and the second lens 74 are, for example, convex lenses.

  The dichroic mirror 80 is disposed in the optical path from the condensing optical system 70 to the rotating fluorescent plate 33 so as to intersect with each of the optical axis of the light source device 10 and the illumination optical axis 103ax at an angle of 45 °. The dichroic mirror 80 reflects the laser light L (blue light) and allows red light and green light to pass therethrough.

  The rotating fluorescent plate 33 is a so-called reflection type rotating fluorescent plate. As shown in FIGS. 7 and 8, the rotary fluorescent plate 33 is formed by continuously forming a single fluorescent layer 46 along the rotation direction of the plate 43 on a part of the plate 43 that can be rotated by the motor 50. . The region where the fluorescent layer 46 is formed includes a region where excitation light is incident. The rotating fluorescent plate 33 emits red light and green light toward the same side as the side on which excitation light (blue light) is incident.

  The rotating fluorescent plate 33 rotates at 7500 rpm during use. Although the detailed description is omitted, the diameter of the rotating fluorescent plate 33 is 50 mm, and the optical axis of the excitation light incident on the rotating fluorescent plate 33 is located at a position about 22.5 mm away from the rotation center of the rotating fluorescent plate 33. ing. In other words, the rotating fluorescent plate 33 rotates at a rotation speed such that the condensed spot of the excitation light moves on the fluorescent layer 46 at about 18 m / sec.

  The plate member 43 may be made of a transparent material that transmits excitation light, such as quartz glass, crystal, sapphire, optical glass, or transparent resin, or may be made of an opaque material that does not transmit excitation light, such as metal. In FIG. 8, the plate material 43 is a disk, but the plate material 43 is not limited to a disk. Excitation light emitted from the light source device 10 enters the rotating fluorescent plate 33 from the fluorescent layer 46 side. The fluorescent layer 46 is formed on the plate member 43 through a reflective film 45 that transmits excitation light and reflects visible light.

  As shown in FIG. 4, on the fluorescent layer 42, the attenuation regions D of two adjacent laser beams partially overlap each other, and the light intensity of the two adjacent laser beams is the highest. The laser beam La, the laser beam Lb, and the laser beam Lc are collected on the fluorescent layer 42 so that the high intensity regions C do not overlap each other. Therefore, it is possible to suppress the occurrence of a portion having a large light intensity protruding in the light intensity distribution of the excitation light on the fluorescent layer 46. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 46, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency. Further, since the fluorescent layer 46 is formed on the plate member 43 rotated by the motor 50, the heat of the fluorescent layer 46 generated by the irradiation of the excitation light is dissipated in a wide region along the rotation direction of the plate member 43. . Therefore, a decrease in luminous efficiency that occurs when the output of the excitation light source device is increased is suppressed, and a bright illumination device 103 is provided.

[Fourth Embodiment]
FIG. 9 is a top view showing an optical system of the projector 1004 of the fourth embodiment. In FIG. 9, components common to the projector 1001 of the first embodiment and the projector 1003 of the third embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. These components will be described with reference to FIGS. 2, 3 and 4 as necessary.

  The projector 1004 differs from the projector 1003 of the third embodiment in the configuration of the second illumination device 702. The configuration of the illumination device 103, the liquid crystal light modulation device 400R as the light modulation device, the liquid crystal light modulation device 400G, the liquid crystal light modulation device 400B, the cross dichroic prism 500, and the projection optical system 600 is the same as that of the projector 1003 of the third embodiment. . The configuration of the color separation light guide optical system 200 is the same as that of the projector 1001 of the first embodiment.

  The second illumination device 702 includes a second light source device 710, a condensing optical system 760, a scattering plate 732, and a collimating optical system 60c.

  The condensing optical system 760 includes a first lens 762 and a second lens 764. The condensing optical system 760 causes the blue light to be incident on the scattering plate 732 in a substantially condensed state. The first lens 762 and the second lens 764 are, for example, convex lenses.

  The scattering plate 732 scatters the blue light from the second light source device 710 with a predetermined degree of scattering to obtain blue light having a light distribution similar to fluorescence (red light and green light emitted from the rotating fluorescent plate 33). . As the scattering plate 732, for example, polished glass made of optical glass can be used.

  The blue light diffused by the scattering plate 732 is substantially collimated by the collimating optical system 60c. The collimating optical system 60c includes a first lens 62c that suppresses the spread of blue light emitted from the scattering plate 732, and a second lens 64c that substantially collimates the light incident from the first lens 62c.

  The blue light substantially collimated by the collimating optical system 60 c is reflected by the dichroic mirror 80 and synthesized with the fluorescence (red light and green light) emitted from the rotating fluorescent plate 33. Then, the light (red light and green light) emitted from the rotating fluorescent plate 33 is color-separated by the color separation light guide optical system 200 and modulated by the liquid crystal light modulation device 400B.

  As shown in FIG. 4, on the fluorescent layer 42, the attenuation regions D of two adjacent laser beams partially overlap each other, and the light intensity of the two adjacent laser beams is the highest. Laser light La, laser light Lb, and laser light Lc are collected on the fluorescent layer 46 so that the high-intensity regions C do not overlap each other. Therefore, it is possible to suppress the occurrence of a portion having a large light intensity protruding in the light intensity distribution of the excitation light on the fluorescent layer 46. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 46, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency. Further, since the fluorescent layer 46 is formed on the plate member 43 rotated by the motor 50, the heat of the fluorescent layer 46 generated by the irradiation of the excitation light is dissipated in a wide region along the rotation direction of the plate member 43. . Therefore, a decrease in luminous efficiency that occurs when the output of the excitation light source device is increased is suppressed, and a bright illumination device 103 is provided.

[Fifth Embodiment]
10 and 11 are modifications of the arrangement of the beam spots shown in FIG.

  In the example of FIG. 4A, the beam spots of a plurality of laser beams emitted from a plurality of light source devices are arranged one-dimensionally on the fluorescent layer 42, but in the examples of FIGS. Laser beam spots are arranged two-dimensionally on the fluorescent layer 42. The example of FIG. 10 is an example in which a plurality of beam spots are two-dimensionally periodically arranged so that the centers of four adjacent beam spots are arranged at four vertices of a square, and the example of FIG. This is an example in which a plurality of beam spots are two-dimensionally and periodically arranged so that three adjacent beam spots are arranged at three vertices of an equilateral triangle. In the example of FIGS. 10 and 11, the number of beam spots on the fluorescent layer 42 is 17 or 13, but the number of beam spots is not limited to this.

  In the example of FIGS. 10 and 11, as in the example of FIG. 4A, the center interval H between the beam spots of two laser beams adjacent to each other on the fluorescent layer 42 is the radius of the beam spot of each laser beam. Greater than S. Thereby, on the fluorescent layer 42, the attenuation regions D of the two adjacent laser beams partially overlap each other, and the high intensity regions C having the highest light intensity of the two adjacent laser beams are mutually connected. A plurality of laser beams are collected on the fluorescent layer 42 so as not to overlap.

  However, it is not essential that the high-intensity region C of the laser beam does not overlap with the attenuation region D of the adjacent laser beam, and at least adjacent laser beams so that the beam spots of the adjacent laser beams do not overlap each other. It is only necessary that the centers of the light beam spots be spaced apart (so as not to overlap) on the fluorescent layer 42.

  Also in the configuration of FIGS. 10 and 11, the occurrence of a portion having a large light intensity protruding in the light intensity distribution of the excitation light on the fluorescent layer 42 is suppressed. Therefore, compared with the case where the high-intensity region Ca of the laser light La is overlapped with the high-intensity region Cb of the laser light Lb on the fluorescent layer 42, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency.

[Sixth Embodiment]
In the present embodiment, another modification of the arrangement of the beam spots shown in FIG. 4A will be described. FIG. 12 is a diagram showing the light intensity distribution of the excitation light on the straight line K including the high-intensity region Ca of the laser light La and the high-intensity region Cb of the laser light Lb on the fluorescent layer 42. The light intensity of the high-intensity region Ca of the laser light La on the fluorescent layer 42 is Ia, and the light intensity of the high-intensity region Cb of the laser light Lb on the fluorescent layer 42 is Ib.

  In the present embodiment, as shown in FIG. 12, on the straight line K, the region where the light intensity of the laser light La is Ia / 2 and the region where the light intensity of the laser light Lb is Ib / 2 overlap each other. Yes. According to this, compared with the case where the region where the light intensity of the laser light La is less than Ia / 2 and the region where the light intensity of the laser light Lb is less than Ib / 2 overlap each other on the straight line K. The reduction in the light intensity of the excitation light in the region between the high-intensity region Ca of the laser light La and the high-intensity region Cb of the laser light Lb can be suppressed. Therefore, in the light intensity distribution on the fluorescent layer 42 of the excitation light irradiated to the fluorescent layer 42, it is suppressed that the site | part which has a large light intensity | strength protrudes. Therefore, fluorescence can be obtained with higher efficiency, and as a result, a brighter illumination device 101 is provided.

  As shown in the fifth embodiment, the beam spots shown in the present embodiment are arranged in a two-dimensional manner on the fluorescent layer 42 such that the beam spots of a plurality of laser beams emitted from a plurality of light source devices are arranged. It can also be applied to cases.

[Deformation]
In the projectors of the second to fourth embodiments, the second illumination device is separately provided as the illumination light source for the liquid crystal light modulation device 400B. However, such a configuration is also applicable to the projector of the first embodiment. Can do.

  Although the example which radiates | emits red light and green light by blue excitation light was demonstrated as a fluorescent layer formed in a rotation fluorescent plate, a fluorescent layer is not limited to such a thing. For example, a fluorescent layer that uses violet light or ultraviolet light as excitation light and emits three color lights of red light, green light, and blue light by the excitation light may be used.

  Although the example in which the fluorescent layer is continuously formed along the rotation direction of the plate material has been described, the configuration of the fluorescent layer is not limited thereto. As in the rotating fluorescent plate of Patent Document 1, a plurality of types of fluorescent layers may be formed along the rotation direction of the plate material, and a plurality of color lights may be sequentially emitted. A plurality of color lights sequentially emitted from the rotating fluorescent plate are modulated by one light modulation device to form a color image.

  Such a rotating fluorescent plate also includes a condensing optical system in which the high-intensity region Ca of the laser light La and the high-intensity region Cb of the laser light Lb are separated from each other on the fluorescent layer. Generation | occurrence | production of the site | part which protrudes and has high light intensity is suppressed. Thereby, compared with the case where the high intensity area | region Ca of the laser beam La is overlapped with the high intensity area | region Cb of the laser beam Lb on the fluorescent layer 42, or when the output of the light source device is increased using only one light source device. Thus, fluorescence can be obtained with high efficiency, and as a result, a bright illumination device is provided.

10, 10a, 10b, 10c ... light source device, 20, 70 ... condensing optical system, 40, 43 ... plate material, 42, 46 ... fluorescent layer, 50 ... motor, 101, 102, 103 ... illumination device, 400R, 400G, 400B ... light modulation device, 600 ... projection optical system, 1001, 1002, 1003, 1004 ... projector, BS ... beam spot of excitation light on the fluorescent layer, C, Ca, Cb, Cc ... high intensity region, D, Da, Db, Dc ... attenuation region, La, Lb, Lc ... light

Claims (6)

A first light source device that emits first light;
A second light source device that emits second light;
A fluorescent layer excited by the first light and the second light;
At least a part of the first light and at least a part of the second light overlap each other on the fluorescent layer, and light out of the first light beam spot formed on the fluorescent layer. The first high intensity region having the highest intensity and the second high intensity region having the highest light intensity among the beam spots of the second light formed on the fluorescent layer are separated from each other on the fluorescent layer. And a condensing optical system for irradiating the fluorescent layer with the first light and the second light. The beam spot of the first light formed on the fluorescent layer includes a first attenuation region in which the light intensity gradually attenuates at the periphery of the first high-intensity region,
The beam spot of the second light formed on the fluorescent layer includes a second attenuation region where the light intensity gradually attenuates at the periphery of the second high intensity region,
The condensing optical system is configured so that the first attenuation region and the second attenuation region are not overlapped with each other on the fluorescent layer. The illumination device according to claim 1, wherein the fluorescent layer is irradiated with the first light and the second light so that they do not overlap each other. The beam spot of the first light formed on the fluorescent layer includes a first attenuation region in which the light intensity gradually attenuates at the periphery of the first high-intensity region,
The beam spot of the second light formed on the fluorescent layer includes a second attenuation region where the light intensity gradually attenuates at the periphery of the second high intensity region,
In the condensing optical system, the light intensity of the first light is in the first high intensity region on a straight line including the first high intensity region and the second high intensity region on the fluorescent layer. The first light and the second light so that a region where the light intensity of the second light is ½ of the light intensity of the second high-intensity region overlap with each other. The illumination device according to claim 1, wherein the fluorescent layer is irradiated with the second light.   The lighting device according to claim 1, wherein the fluorescent layer is continuously formed on a plate member rotated by a motor along a rotation direction of the plate member.   The illumination device according to claim 1, wherein the light source device is a laser light source that emits laser light. The lighting device according to any one of claims 1 to 5,
A light modulation device that modulates illumination light from the illumination device according to image information;
And a projection optical system that projects the modulated light from the light modulation device as a projection image.

Images