JPH10190058A - UV irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To irradiate limitedly on a spot and facilitate miniaturization by a method wherein a solid luminous element for emitting ultraviolet rays unidirectionally is disposed facing an object. SOLUTION: In this ultrasonic irradiator, AlGaN system DH structure ultraviolet rays LED1 in which wavelength is 257nm, optical output at the current conduction of 50mA is 10mW, and orientation half-value angle is ±15 deg. are formed, and 12 ultraviolet rays LED's 1 are used. These 12 ultraviolet rays LED's 1 are densely disposed within a circular plane surface 2 of a diameter 30mm, and also luminous directions are aligned in parallel. Further, a dry cell of a power source and a power source switch are housed inside a light source box 3 having this plane 2. Thereby, these circular beams can be obtained substantially. The light source box 3 is directed to an object and a power source switch is turned on, whereby a surface of the object can be irradiated in the range of a circle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet irradiation apparatus for irradiating ultraviolet rays, and more particularly to an ultraviolet irradiation apparatus capable of local irradiation, easily downsized, and long-term reliable. .

[0002]

2. Description of the Related Art Ultraviolet irradiation apparatuses are used in various fields such as medical treatment and industry. For example, an ultraviolet irradiation device is used for disinfection, skin disease treatment and the like for medical use or consumer use. Further, for industrial use, an ultraviolet irradiation device is used as a light source for a curing process of an ultraviolet curable resin utilizing a photochemical reaction, a material evaluation device, and the like.

[0003] As a light source of such an ultraviolet irradiation device, a mercury lamp utilizing discharge in mercury vapor has been generally used. Others include He-Cd lasers, and special ones utilizing synchrotron radiation. However, these devices are bulky and expensive, and are not suitable for a light source for constructing an ultraviolet irradiation device that can be easily used.

[0004]

A mercury lamp has a glass discharge tube filled with mercury vapor, and emits ultraviolet light from the entire circumference of the discharge tube when lit. For this reason, ultraviolet rays cannot be locally emitted only to the target object. Some mercury lamps have a reflective film coated on a part of the discharge tube wall, but it is still difficult to locally emit ultraviolet light.

[0005] For example, in the case of irradiating ultraviolet rays in the treatment of skin diseases, it is desirable to irradiate ultraviolet rays only to a portion requiring treatment according to the shape of the affected area and not to irradiate other parts with ultraviolet rays. Such local irradiation was not possible with the irradiation device.

It is important that unnecessary ultraviolet rays are not leaked to the surroundings so that the ultraviolet rays do not enter human eyes or irradiate the skin or the like in a large amount. For this reason, mercury lamps are usually housed inside UV shields,
Nevertheless, it was inevitable that UV light would leak from between the UV shield and the object, and people engaged in UV handling or receiving UV treatment had to wear UV protective goggles and glasses. .

[0007] In addition, the mercury lamp requires a high-voltage power supply circuit to generate electric discharge, so that it is inevitably difficult to miniaturize the ultraviolet irradiation device, and the lamp itself has a short life. Was.

An object of the present invention is to solve the above-mentioned problems and to provide an ultraviolet irradiation apparatus which can perform irradiation limited to a local area, can be easily miniaturized, and has long-term reliability.

[0009]

In order to achieve the above object, the present invention comprises at least Ga, In or Al.
A solid-state light-emitting element that emits ultraviolet light in one direction is formed using a nitride semiconductor of a group III element, and the light-emitting element is arranged so as to face an object.

A light source housing having a flat or concave surface on one side may be formed, and a number of the light emitting elements may be arranged on the flat or concave surface.

The light source housing may be attached to one end of a flexible tube.

[0012]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

According to the ultraviolet irradiation apparatus of the present invention, a solid state light emitting device which emits ultraviolet light in one direction is formed using a nitride semiconductor of a group III element containing at least Ga, In or Al. It is arranged to face. Here, as a nitride semiconductor of a group III element containing at least Ga, In or Al, InxGayAl
(1-xy) N (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0
≦ x + y ≦ 1) is used. The solid state light emitting device can be in the form of an LED (light emitting diode) or an LD (laser diode).

Here, a light emitting device using a GaN-based material among nitride semiconductors of group III elements can emit light of a short wavelength. For example, in an LED using GaN as an active layer,
Ultraviolet light having a wavelength of 360 nm is obtained. The following documents are disclosed as examples of such an ultraviolet light emitting diode.

Reference: "GaN pn junction blue / ultraviolet light emitting diode", Applied Physics Vol. 60, No. 2 (1991), Amano, Akasaki.

A light emitting device using a nitride semiconductor of a group III element containing Al can also emit light of a short wavelength. In particular, A
The light emitting element using the lGaN mixed crystal can change the band gap in the range of 3.44 to 6.20 eV, and by using this as an active layer, ultraviolet light emission of 200 to 360 nm can be obtained. For example, GaxAl (1-x)
In an LED using N (where 0 ≦ x ≦ 1) as an active layer, ultraviolet rays having a wavelength of 360 to 200 can be obtained by changing the composition x.

In the present invention, the reason that the material contains In in addition to Al is that, depending on the structure of the light emitting element, when GaN-based epitaxial growth is performed on the substrate,
This is because the crystallinity of the active layer is improved when a layer containing n is interposed.

The ultraviolet irradiation apparatus of the present invention is characterized in that
The EDs are arranged in a circular plane as shown in FIG. 1 or a light source housing having a concave surface is formed and arranged in the concave surface as shown in FIG. 2, and each ultraviolet LED has a directivity. Therefore, the light emitting directions are aligned in a parallel or centripetal manner. Further, as shown in FIG. 3, the light source housing having the flat surface or the concave surface may be attached to one end of the flexible tube.

As shown in FIG. 4, the circuit of the ultraviolet irradiation device is such that a control resistor is connected in series to each of a plurality of ultraviolet LEDs, and a set of these ultraviolet LEDs and the control resistor is connected in parallel or FIG. As shown in FIG. 1, a plurality of ultraviolet LEDs connected in series together with a control resistor are connected in parallel.

A first embodiment will be described with reference to FIG. This ultraviolet irradiation device has a wavelength of 257 nm, 50 m
A with an optical output of 10 mW and a light distribution half-value angle of ± 15 °
The 1GaN-based DH structure ultraviolet LED 1 is formed, and 12 ultraviolet LEDs 1 are used. As shown in FIG. 4, the twelve ultraviolet LEDs 1 are connected to control resistors 4 connected in series.
1 and connected in parallel. The power source 42 is a single 2 dry cell 3
Books are connected in series and set to 4.5V. Power switch 4
3 turns on and off. These one
The two ultraviolet LEDs 1 are densely arranged in a circular plane 2 having a diameter of 30 mm as shown in FIG. 1 and their light emitting directions are aligned in parallel. Although not shown in this figure, the light source housing 3 having the flat surface 2 is a cylinder having a diameter of 30 mm and a length of 180 mm, in which the dry battery of the power source 42 and the power switch 43 are accommodated. Has the plane 2 described above.

In this embodiment, since the twelve ultraviolet LEDs 1 are densely arranged in the circular plane 2 and the emission directions are aligned in parallel, it is possible to obtain a light beam having a substantially circular shape. Then, by turning on the power switch 43 with the light source housing 3 applied to the object, the surface of the object can be irradiated in a circular range.

FIG. 3 shows a second embodiment. This ultraviolet irradiation apparatus accommodates, in a cylindrical light source housing 32, a dense array of the same twelve ultraviolet LEDs 1 used in FIG. 1 and a stainless steel light source housing 32 capable of freely changing its direction. Flexible tube 33
It is attached to. A lead wire for supplying power to the ultraviolet LED is accommodated in the flexible tube 33.
Three such flexible tubes with a light source housing are provided, each containing a box 34 containing a DC constant current source as shown in the figure.
Attached to. By changing the set current of the DC constant current source in the range of 0 to 4 A, the emission output of ultraviolet light can be changed in the range of 0 to 500 mW.

In this embodiment, since the light source housing 32 is attached to one end of the flexible tube (flexible tube 33), the light source housing 32 faces a desired portion of the object and is held stationary. Can be done.

A third embodiment will be described with reference to FIG. This ultraviolet irradiation device has a wavelength of 290 nm, 50 m
Al with light output of 12 mW when A is energized and half angle of light distribution ± 8 °
A GaN-based UV LED 21 having a DH structure is formed, and 256 UV LEDs 21 are used. These two
As shown in FIG. 5, the 56 ultraviolet LEDs 21 are connected in parallel with a plurality of ultraviolet LEDs 21 connected in series together with a control resistor 51. The light source housing 22 has a hemispherical shell-like or semi-cylindrical concave surface 23.
3, 256 ultraviolet LEDs 21 are densely arranged, and the light emitting directions are aligned in a centrifugal manner. As the power supply 52, the same DC constant current source 34 as in FIG. 3 is used.

In this embodiment, since 256 ultraviolet LEDs 21 are densely arranged on the concave surface 23 of a hemispherical shell or a semi-cylindrical shape and the light emitting directions are aligned in a centrifugal manner, the focal point is one point or one line. Become. The UV intensity at the focus can be up to 2.2 W / cm ² . This light source housing 2
In making the object 2 face the object, it is possible to irradiate a point or a linear object or a point or a linear portion on the surface of a planar object. By using it over, it is possible to prevent light leakage from the gap and to achieve uniform irradiation within the irradiation range without creating a shadow on the convex target object.

Although not shown, the fourth embodiment uses a combination of an ultraviolet light emitting element and a visible light emitting element. In this case, the visible light emitting element can be basically made of the same material and the same structure and shape as the ultraviolet light emitting element, so that a power supply and a circuit for lighting the light emitting element and a light source housing for housing the same are all common. Can be used. And it is comprised so that an ultraviolet ray and a visible light can be lighted simultaneously, or can be lighted independently of each other. This allows
It is possible to easily confirm the irradiation range of the object and the presence / absence of light leakage.

As described above, in the ultraviolet irradiation apparatus of the present invention, a solid-state light emitting element that emits ultraviolet light in one direction is formed by using a nitride semiconductor of a Group III element containing at least Ga, In or Al. Depending on the composition ratio, an ultraviolet ray having an arbitrary wavelength can be obtained, and the ultraviolet ray can have directivity. By arranging the light emitting element so as to face the object, irradiation limited to a local area is possible.
In addition, since a solid-state light-emitting element is used, a driving power supply can be constituted by a low-voltage constant current source, miniaturization is possible, and the light-emitting element itself has good durability. In addition, since the light intensity can be changed by the current, the light intensity can be easily adjusted. Then, the mode in which the light emitting element is arranged facing the object can be freely arranged three-dimensionally as well as a flat surface and a concave surface, and the shape or irradiation range of the object facing the object can be any shape or surface. Thus, points, straight lines, free curves, and the like, which were impossible in the past, are possible.
Further, a three-dimensional arrangement can be applied to a curved surface of an object. Furthermore, handling is simplified by attaching the light source housing to one end of the flexible tube.

In each of the embodiments described above, the object is irradiated with ultraviolet rays directly from the light emitting element. However, a lens may be attached to the light emitting element, and the light may be condensed and irradiated.

Next, a preferred application example of the ultraviolet irradiation apparatus of the present invention will be described. First, for medical use, when treating skin diseases etc., by changing the arrangement of the light emitting elements and the direction of the light source housing, it is possible to irradiate only the affected part with ultraviolet rays and not irradiate unnecessary parts with ultraviolet rays. it can. In particular, by arranging the light emitting elements three-dimensionally according to the shape of the body,
It is possible to achieve uniform irradiation to the local area and prevent unnecessary ultraviolet rays from leaking to the surroundings. And, it is possible to make a handy ultraviolet irradiation device that uses a dry cell as a power source, and configure a treatment device that can be carried anywhere and applied to any part of the body, for example, for the treatment of ringworm, athlete's foot, etc. Thus, such a therapeutic device can be used easily and with peace of mind. For industrial use, when there is a request to cause a partial photochemical reaction, for example, we want to etch metal, semiconductor, etc. in a limited range, or cross-link polymers, etc. in a limited range At times, local ultraviolet irradiation is performed by the ultraviolet irradiation device of the present invention. Also in this case, as in the case of medical use, it is possible to achieve uniform irradiation to the local area and prevent unnecessary ultraviolet rays from leaking to the surroundings.

Further, since ultraviolet light is invisible and can excite many fluorescent substances to emit light,
It can be used for various sensors such as a night vision sensor and an analysis sensor. In this case, the ultraviolet irradiation device of the present invention has specifications required for the light source for the sensor, such as strong directivity and monochromaticity of ultraviolet light, easy downsizing, low power consumption, and long life. Can all be satisfied.

[0031]

The present invention exhibits the following excellent effects.

(1) Since the solid-state light-emitting element that emits ultraviolet light in one direction is arranged facing the object, it can be freely arranged, and it is possible to irradiate only necessary parts and irradiate unnecessary parts. Irradiation limited to a local area that does not occur is enabled.

(2) Since a solid-state light-emitting element is used, the driving power supply can be constituted by a low-voltage constant current source, the size can be reduced, and the light-emitting element itself has good durability. In addition, since the light intensity can be changed by the current, the light intensity can be easily adjusted.

(3) The emission wavelength can be changed in a wide range by selecting a material, and a single wavelength can be used, so that it can be widely applied to processing, sensors, and the like.

(4) Since a large number of light emitting elements are arranged on a plane or a concave surface, linear irradiation or even irradiation on a curved surface can be performed.

(5) Since the light source housing is attached to one end of the flexible tube, handling is simplified.

[Brief description of the drawings]

FIG. 1 is a front view of an ultraviolet irradiation device according to an embodiment of the present invention.

FIG. 2 is a sectional view of an ultraviolet irradiation device according to another embodiment of the present invention.

FIG. 3 is a perspective view of an ultraviolet irradiation device showing another embodiment of the present invention.

FIG. 4 is a circuit diagram of the ultraviolet irradiation device of the present invention.

FIG. 5 is a circuit diagram of the ultraviolet irradiation device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 21 Light emitting element 2 Plane 3, 22 Light source housing 23 Concave surface 33 Flexible tube

Claims (3)

[Claims] 1. A solid-state light-emitting device that emits ultraviolet light in one direction using a nitride semiconductor of a group III element containing at least Ga, In or Al is formed, and the light-emitting device is arranged facing an object. An ultraviolet irradiation device, characterized in that: 2. The ultraviolet irradiation apparatus according to claim 1, wherein a light source housing having a flat surface or a concave surface on one side is formed, and a plurality of the light emitting elements are arranged on the flat or concave surface. 3. The ultraviolet irradiation device according to claim 2, wherein said light source housing is attached to one end of a flexible tube.