CN115453716A - A kind of optical projection system and projection device - Google Patents

Abstract

The application discloses an optical projection system and a projection device, wherein the optical projection system sequentially comprises a first lens group, a diaphragm and a second lens group from an enlargement side to a reduction side; the first lens group and the second lens group respectively comprise at least three lenses; the focal power of the first lens group is negative, and the focal power of the second lens group is positive; the ratio of the total length TL of the optical projection system to the aperture D of the largest lens in all the lenses meets the condition that the TL/D is less than 1 and less than 3.1.

Description

A kind of optical projection system and projection device

technical field

The present application relates to the technical field of optical equipment, and more specifically, to an optical projection system and a projection device.

Background technique

With the vigorous development of science and technology, projection technology has become increasingly mature, and the application fields of projection equipment have become wider and wider, such as in commercial fields such as conference explanations, tour exhibitions and promotional activities, in school teaching, academic discussions, etc. The field of education, as well as the home field such as home theater. In recent years, Digital Light Processing (DLP) projection devices have become the mainstream technology of current projection devices, and they are the best choice among projection display products in terms of lightness, durability, high brightness, and high contrast.

Digital light processing projection systems are mostly used in interactive smart speakers, pocket mini projectors, game consoles and other equipment; in recent years, imaging lenses designed using DLP projection technology are also increasingly used in 3D printing systems go. Imaging design indicators in 3D printing generally pay more attention to clarity and distortion performance indicators; and also hope to reduce the volume as much as possible.

Therefore, how to provide a digital light processing projection system that can meet the requirements of high-precision 3D printing equipment with a smaller volume has become one of the research topics in the industry.

Contents of the invention

An object of the present application is to provide a new technical solution for an optical projection system and a projection device.

According to the first aspect of the present application, an optical projection system is provided, and the optical projection system sequentially includes from the enlargement side to the reduction side:

The first lens group, the diaphragm and the second lens group;

The first lens group and the second lens group respectively include at least three lenses;

The refractive power of the first lens group is negative, and the refractive power of the second lens group is positive;

The ratio between the total length TL of the optical projection system and the diameter D of the largest lens among all the lenses satisfies 1<TL/D<3.1.

Optionally, the optical projection system satisfies 8.0mm<effl<9.3mm, where effl is the effective focal length of the optical projection system.

Optionally, the first lens group includes a first lens, a second lens and a third lens arranged in sequence from the magnification side to the reduction side; the second lens group includes a fourth lens arranged in sequence from the magnification side to the reduction side lens, fifth lens, sixth lens and seventh lens;

The refractive power of the third lens is negative, and the refractive power of the fourth lens is positive.

Optionally, the effective focal length f3 of the third lens satisfies -27.838mm<f3<-20.22mm; the effective focal length f4 of the fourth lens satisfies 12.3mm<f4<18.8mm.

Optionally, the first lens group includes a first lens, a second lens and a third lens arranged in sequence from the magnification side to the reduction side; the second lens group includes a fourth lens arranged in sequence from the magnification side to the reduction side Lens, fifth lens, eighth lens;

The refractive power of the third lens is negative, and the refractive power of the fourth lens is positive.

Optionally, at least one of the enlargement side and the reduction side of the fifth lens is a concave surface.

Optionally, the effective focal length f5 of the fifth lens satisfies -37.7mm<f5<-30.1mm; the effective focal length f8 of the eighth lens satisfies 10.3mm<f8<16.28mm.

Optionally, the ratio of the distance from the third lens to the diaphragm to the distance from the fourth lens to the diaphragm is in the range of 1-5.

Optionally, the optical projection system further includes a vibrating mirror, and the vibrating mirror is disposed on a side of the second lens group away from the diaphragm.

According to a second aspect of the present application, a projection device is provided, and the projection device includes the optical projection system as described in the first aspect.

In the optical projection system provided in the embodiment of the present application, through the optimal configuration of various parameters, it can achieve better imaging effect and smaller volume size; moreover, it can achieve small distortion of projected image, high resolution and MTF modulation Highly functional image effects.

Other features of the present application and advantages thereof will become apparent through the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate the embodiments of the application and together with the description serve to explain the principles of the application.

FIG. 1 is a schematic diagram of an optical structure of an optical projection system of the present application;

FIG. 2 is a schematic diagram of an optical structure of an optical projection system of the present application;

FIG. 3 is a schematic diagram of the modulation transfer function of Embodiment 1 in an optical projection system of the present application;

FIG. 4 is a schematic diagram of a modulation transfer function of Embodiment 2 in an optical projection system of the present application.

Explanation of reference signs:

1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; 9. Equivalent prism; 10. Protective glass; 11. Display chip; 12. Aperture; 13. Vibrating mirror.

detailed description

Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as any limitation of the application, its application or uses.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the description.

In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

Referring to Figures 1-2, according to an embodiment of the present application, an optical projection system is provided, the optical projection system includes a first lens group, a diaphragm 12 and a second lens in order from the enlargement side to the reduction side group; the first lens group and the second lens group respectively include at least three lenses; the refractive power of the first lens group is negative, and the refractive power of the second lens group is positive; the The ratio between the total length TL of the optical projection system and the diameter D of the largest lens among all the lenses satisfies 1<TL/D<3.1.

The optical projection system provided by the embodiment of the present application also includes an equivalent prism 9, a protective glass 10, and a display chip 11; The light or the reflected light is transmitted into the lens; the protective glass 10 is used to protect the display chip 1 from the influence of external pollutants; the display chip 11 can be a digital micromirror device display panel (DMD), a silicon-based liquid crystal display panel (LCOS), liquid crystal display panel (LCD), etc. It can be understood that the display chip 11 is a laser light source of different wavelengths or other light sources capable of emitting light beams.

The optical projection system provided by the embodiment of the present application is applied to a projection device; the optical projection system includes a reduction side and an enlargement side along the light transmission direction, and the display chip 11, the protective glass 10, the equivalent prism 9, and the second lens in the optical projection system The group, the diaphragm 12 and the first lens group are sequentially arranged between the reduction side and the enlargement side along the same optical axis. Wherein, the zoom-out side is the side where the image source (such as the display chip 11) generating the projection light is located during the projection process, that is, the image side; the zoom-in side is the projection surface (such as a projection screen) for displaying the projected image during the projection process. ) is located on the side, that is, the object space. The transmission direction of the projection light is from the reduction side to the enlargement side. But in the actual design of the optical projection system, according to the reversible principle of the optical path, the light is simulated from the actual enlargement side to the reduction side.

Specifically, in the actual projection process, the projection light is emitted by the display chip 11, and is emitted from the reduction side to the enlargement side, and passes through the protective glass 10, the equivalent prism 9, the second lens group, the diaphragm 12 and the first lens group in sequence. , which displays the projected image.

In the embodiment of the present application, a digital micromirror device (Digital Micromirror Device, DMD) chip may be used as the display chip 11 as the image source. DMD is composed of many digital micro-mirrors arranged in a matrix. When working, each micro-mirror can be deflected and locked in two directions, so that the light is projected in a predetermined direction, and at a frequency of tens of thousands of hertz Swing, the light beam from the illumination source is reflected by the flip of the micro-mirror and enters the optical system to be imaged on the screen. DMD has the advantages of high resolution and no need for digital-to-analog conversion of signals. The embodiment of the present application uses a 0.3-inch DMD with an aspect ratio of 16:9. The specific size may be, for example, 6.912*3.888mm. The minimum projection ratio of the matched design is 1.1, and the maximum offset is 100%. It should be noted that the image source size applicable to the imaging optical path structure in the embodiment of the present application is not limited to 0.3-inch DMD, 100% bias, the size of the total image source allowed by the embodiment of the present application can be within 5.2 mm, and the full field of view within 64°. Of course, the display chip 11 as the image source can also be a liquid crystal on silicon (LCOS) chip, a liquid crystal display panel (liquid crystal display, LCD) or other display elements that can emit light, which is not limited in this application.

In this embodiment, lens groups are respectively arranged on both sides of the diaphragm 12 , one side of the two sides is close to the enlargement side, and the other side is close to the reduction side. Wherein, the side close to the enlargement of the diaphragm 12 is set as the first lens group, and the side close to the reduction of the stop 12 is set as the second lens group. Wherein, the first lens group and the second lens group respectively include at least three lenses; and the refractive power of the first lens group is negative, and the refractive power of the second lens group is positive. In the optical projection system of the embodiment of the present application, the inverse telephoto optical group scheme is adopted, and the optical power distribution follows the negative-positive distribution method, and the optical power of the entire optical projection system is balanced to meet the requirements of the projection system for image value. In addition, by reasonably matching the optical power of the two lens groups, the optical power balance of the entire optical projection system can be ensured to meet the requirements of 3D printing image value. Among them, the refractive power of the first lens group is negative, and the refractive power of the second lens group is positive, which helps to meet the requirements of 3D printing for low distortion and 3D printing for high-resolution images.

In addition, in the optical projection system provided in the embodiment of the present application, by setting the ratio between the total length TL of the optical projection system and the diameter D of the largest lens among all the lenses to satisfy 1<TL/D<3.1, In this way, the structure of the optical projection system can be made compact while ensuring the quality of the imaging picture, thereby ensuring the small size of the optical projection system to a certain extent, and making the optical projection system easy to carry and use. That is to say, in the optical projection system provided by the embodiment of the present application, the imaging effect of the optical projection system can be improved while reducing the volume of the optical projection system, so as to ensure the high definition and low distortion performance requirements of 3D printing. The optical projection system provided by the embodiment of the present application has small distortion of the projected image, high resolution and high MTF modulation function.

In one embodiment, the optical projection system satisfies 8.0mm<effl<9.3mm, where effl is the effective focal length of the optical projection system.

In this specific example, by setting the value of the effective focal length effl of the optical projection system to 8.0mm<effl<9.3mm, the structure of the optical projection system can be made compact while ensuring the quality of the imaging picture, thus to a certain extent The size of the optical projection system is ensured to be small, so that the optical projection system is easy to carry and use.

Referring to Fig. 1, in one embodiment, the first lens group includes a first lens 1, a second lens 2 and a third lens 3 arranged sequentially from the magnification side to the reduction side; the second lens group includes The fourth lens 4, the fifth lens 5, the sixth lens 6, and the seventh lens 7 are arranged in order from the enlargement side to the reduction side; the refractive power of the third lens 3 is negative, and the light of the fourth lens 4 Focus is positive.

In this specific example, the optical projection system uses 7 spherical mirrors, which are arranged in order from the enlargement side to the reduction side as the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, and the fifth lens 5 , the sixth lens 6 and the seventh lens 7 . Among them, the first lens group consisting of the first lens 1, the second lens 2 and the third lens 3 is located near the magnification side of the diaphragm 12; the fourth lens 4, the fifth lens 5, the sixth lens 6 and the seventh lens The second lens group composed of lenses 7 is located near the narrowing side of the diaphragm 12; and, the third lens 3 is the closest to the diaphragm 12 in the first lens group, and the fourth lens is the closest to the diaphragm 12 in the second lens group. Lens 4; the refractive power of the third lens 3 is negative, and the refractive power of the fourth lens 4 is positive. The lens arrangement design in this embodiment ensures that the volume size of the optical projection system is small and at the same time ensures low cost.

In one embodiment, the enlarged side of the first lens 1 is convex; the enlarged side of the second lens 2 is convex, and the reduced side is concave; the enlarged side of the third lens 3 is convex, and the reduced side is Concave; at least one of the enlarged side and the reduced side of the fourth lens 4 is a convex surface; the enlarged side of the fifth lens 5 is concave, and the reduced side is concave; the enlarged side of the sixth lens 6 is convex 1. The reducing side is convex; the enlarged side of the seventh lens 7 is convex, and the reducing side is convex.

In this specific example, through the above surface structure design, the entire optical projection system can achieve higher image value requirements and light gathering capabilities.

In one embodiment, the effective focal length f3 of the third lens 3 satisfies -27.838mm<f3<-20.22mm; the effective focal length f4 of the fourth lens 4 satisfies 12.3mm<f4<18.8mm. Moreover, the effective focal length f1 of the first lens 1 satisfies 40.56mm<f1<50mm; the effective focal length f2 of the second lens 2 satisfies -13.15mm<f2<-9.175mm; the effective focal length of the fifth lens 5 f5 satisfies -26.16mm<f5<-21.6mm; the effective focal length f6 of the sixth lens 6 satisfies 16.3mm<f6<21.9mm; the effective focal length f7 of the seventh lens 7 satisfies 21.3mm<f7<28.7mm. The ratio of the distance from the third lens 3 to the diaphragm 12 to the distance from the fourth lens 4 to the diaphragm 12 ranges from 1 to 5.

In this specific example, through the effective focal length f1 of the first lens 1, the effective focal length f2 of the second lens 2, the effective focal length f3 of the third lens 3, the effective focal length f4 of the fourth lens 4, and the effective focal length of the fifth lens 5 The effective focal length f5, the effective focal length f6 of the sixth lens 6 and the effective focal length f7 of the seventh lens 7 are limited; and by the ratio of the distance from the third lens 3 to the diaphragm 12 and the distance from the fourth lens 4 to the diaphragm 12 The scope is limited; the optical design index can be optimized, and the radial size of the optical projection system can be effectively reduced while satisfying the imaging quality, which is conducive to the thinning and miniaturization design of the optical projection system.

Referring to Fig. 2, in one embodiment, the first lens group includes a first lens 1, a second lens 2 and a third lens 3 arranged sequentially from the magnification side to the reduction side; the second lens group includes The fourth lens 4, the fifth lens 5, and the eighth lens 8 are arranged sequentially from the enlargement side to the reduction side; the refractive power of the third lens 3 is negative, and the refractive power of the fourth lens 4 is positive.

In this specific example, the optical projection system uses 6 spherical mirrors, which are arranged sequentially from the enlargement side to the reduction side as the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, and the fifth lens 5 And the eighth lens 8. Wherein, the first lens group consisting of the first lens 1, the second lens 2 and the third lens 3 is located near the magnification side of the diaphragm 12; the first lens group consisting of the fourth lens 4, the fifth lens 5 and the eighth lens 8 The two lens groups are located near the narrowing side of the diaphragm 12; and, the third lens 3 is the closest to the diaphragm 12 in the first lens group, and the fourth lens 4 is the closest to the diaphragm 12 in the second lens group; The refractive power of the lens 3 is negative, and the refractive power of the fourth lens 4 is positive. The number of lenses in this embodiment is small, and the arrangement design of the lenses further reduces the volume size of the optical projection system.

In one embodiment, at least one of the enlargement side and the reduction side of the fifth lens 5 is concave. And, the enlarged side of the first lens 1 is convex; the enlarged side of the second lens 2 is convex, and the reduced side is concave; the enlarged side of the third lens 3 is convex, and the reduced side is concave; At least one of the enlargement side and the reduction side of the fourth lens 4 is a convex surface; the enlargement side of the eighth lens 8 is a convex surface, and the reduction side is a convex surface.

In this specific example, through the above surface structure design, the entire optical projection system can achieve higher image value requirements and light gathering capabilities.

In one embodiment, the effective focal length f5 of the fifth lens 5 satisfies -37.7mm<f5<-30.1mm; the effective focal length f8 of the eighth lens 8 satisfies 10.3mm<f8<16.28mm. Moreover, the effective focal length f1 of the first lens 1 satisfies 40.56mm<f1<50mm; the effective focal length f2 of the second lens 2 satisfies -13.15mm<f2<-9.175mm; the effective focal length of the third lens 3 f3 satisfies -27.838mm<f3<-20.22mm; the effective focal length f4 of the fourth lens 4 satisfies 12.3mm<f4<18.8mm. In addition, the ratio of the distance from the third lens 3 to the diaphragm 12 to the distance from the fourth lens 4 to the diaphragm 12 ranges from 1 to 5.

In this specific example, through the effective focal length f1 of the first lens 1, the effective focal length f2 of the second lens 2, the effective focal length f3 of the third lens 3, the effective focal length f4 of the fourth lens 4, and the effective focal length of the fifth lens 5 The effective focal length f5 and the effective focal length f8 of the eighth lens 8 are limited; and by limiting the ratio range of the distance from the third lens 3 to the diaphragm 12 and the distance from the fourth lens 4 to the diaphragm 12; the optical design index can be optimized , while satisfying the imaging quality, the radial size of the optical projection system is effectively reduced, which is beneficial to the thinning and miniaturization design of the optical projection system.

In one embodiment, the optical projection system further includes a vibrating mirror 13 , and the vibrating mirror 13 is disposed on a side of the second lens group away from the diaphragm 12 .

In this specific example, the configuration of the vibrating mirror 13 can improve the resolution of the optical projection system.

The optical projection system provided by the embodiment of the present application has small distortion of the projected image, high resolution and high MTF modulation function; through the optimized configuration of the above parameters, it can achieve high image definition imaging effect in each field of view.

According to another embodiment of the present application, a projection device is provided, and the projection device includes the above-mentioned optical projection system. The projection device may be, for example, a projection device. The projection device may be, for example, a projector, or an illuminating machine or the like.

Example 1:

Referring to Fig. 1, from the enlargement side to the reduction side, the optical projection system is provided with a first lens 1, a second lens 2, a third lens 3, a diaphragm 12, a fourth lens 4, a fifth lens 5, a first lens Six lenses 6, seventh lens 7, vibrating mirror 13, equivalent prism 9, protective glass 10 and display chip 11; the optical projection system meets the effective focal length effl=8.72mm, and the total optical length TL of the optical projection system is 62mm. The 0.3-inch DMD design goals are as follows:

The throw ratio is 1.17, the projection distance is 220mm, the offset is 0%, the wavelength is 400nm-410nm, the TV distortion is <0.5%, the MTF of the full field of view is >0.5@96lp/mm, the telecentricity is <1.5°, the chromatic aberration is <0.5pixel, F#2.5.

The optical projection system in this embodiment includes 7 pieces of spherical mirrors, which are arranged sequentially from the enlargement side to the reduction side as the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens. Lens 6 and the seventh lens 7; Wherein, the enlargement side S1 of the first lens 1 is a convex surface, and the reduction side S2 is a convex surface; the enlargement side S3 of the second lens 2 is a convex surface, and the reduction side S4 is a concave surface; the enlargement of the third lens 3 The side S5 is a convex surface, and the reduction side S6 is a concave surface; the enlargement side S7 and the reduction side S8 of the fourth lens 4 are both convex surfaces; the enlargement side S9 of the fifth lens 5 is a concave surface, and the reduction side S10 is a concave surface; the enlargement of the sixth lens 6 The side S11 is a convex surface, the reduction side S12 is a convex surface; the enlargement side S13 of the seventh lens 7 is a convex surface, and the reduction side S14 is a convex surface.

Each parameter involved in embodiment 1 is shown in table 1 below:

Table 1

The schematic diagram of the modulation transfer function of the optical projection system shown in Example 1 is shown in Figure 3. It can be seen from the diagram that the MTF values of each field of view are higher than 0.75, and it can be seen that the images imaged by the system under each field of view The definition is very high, and other performances also meet the design requirements, which is suitable for the precision requirements of 3D printing.

Example 2:

Referring to Fig. 2, from the enlargement side to the reduction side, the optical projection system is provided with a first lens 1, a second lens 2, a third lens 3, a diaphragm 12, a fourth lens 4, a fifth lens 5, a first lens Eight lenses 8, vibrating mirror 13, equivalent prism 9, protective glass 10 and display chip 11; the optical projection system meets the effective focal length effl=8.89mm, and the total optical length TL of the optical projection system is 66.4mm. The 0.3-inch DMD design goals are as follows:

The throw ratio is 1.17, the projection distance is 220mm, the offset is 0%, the wavelength is 400nm-410nm, the TV distortion is <0.5%, the MTF of the full field of view is >0.5@96lp/mm, the telecentricity is <1.5°, the chromatic aberration is <0.5pixel, F#2.5.

The optical projection system in this embodiment comprises 6 spherical mirrors; wherein, the enlargement side S1 of the first lens 1 is a convex surface, and the reduction side S2 is a convex surface; the enlargement side S3 of the second lens 2 is a convex surface, and the reduction side S4 is a concave surface; The enlargement side S5 of three lenses 3 is a convex surface, and the reduction side S6 is a concave surface; the enlargement side S7 of the fourth lens 4 is a convex surface, and the reduction side S8 is a convex surface; the enlargement side S9 of the fifth lens 5 is a convex surface, and the reduction side S10 is a convex surface. Concave surface; the enlargement side S11 of the eighth lens 8 is a convex surface, and the reduction side S12 is a convex surface.

Each parameter involved in embodiment 2 is shown in table 2 below:

The schematic diagram of the modulation transfer function of the optical projection system shown in Example 2 is shown in Figure 4. It can be seen from the diagram that the MTF values of each field of view are higher than 0.75, and it can be seen that the images imaged by the system under each field of view The definition is very high, and other performances also meet the design requirements, which is suitable for the precision requirements of 3D printing.

Although some specific embodiments of the present application have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration, rather than limiting the scope of the present application. Those skilled in the art will appreciate that modifications can be made to the above embodiments without departing from the scope and spirit of the application. The scope of the application is defined by the appended claims.

Claims (10)

1. An optical projection system, characterized in that it comprises successively from the enlarged side to the reduced side: The first lens group, the diaphragm (12) and the second lens group; The first lens group and the second lens group respectively include at least three lenses; The refractive power of the first lens group is negative, and the refractive power of the second lens group is positive; The ratio between the total length TL of the optical projection system and the diameter D of the largest lens among all the lenses satisfies 1<TL/D<3.1. 2. The optical projection system according to claim 1, wherein the optical projection system satisfies 8.0mm<effl<9.3mm, wherein effl is the effective focal length of the optical projection system. 3. The optical projection system according to claim 1, characterized in that, the first lens group comprises a first lens (1), a second lens (2) and a third lens arranged in sequence from the enlargement side to the reduction side (3); The second lens group includes a fourth lens (4), a fifth lens (5), a sixth lens (6) and a seventh lens (7) arranged in sequence from the magnification side to the reduction side; The refractive power of the third lens (3) is negative, and the refractive power of the fourth lens (4) is positive. 4. The optical projection system according to claim 3, characterized in that, the effective focal length f3 of the third lens (3) satisfies -27.838mm<f3<-20.22mm; the effective focal length f3 of the fourth lens (4) The focal length f4 satisfies 12.3mm<f4<18.8mm. 5. The optical projection system according to claim 1, characterized in that, the first lens group comprises a first lens (1), a second lens (2) and a third lens arranged in sequence from the enlargement side to the reduction side (3); The second lens group includes a fourth lens (4), a fifth lens (5), and an eighth lens (8) arranged in sequence from the magnification side to the reduction side; The refractive power of the third lens (3) is negative, and the refractive power of the fourth lens (4) is positive. 6. The optical projection system according to claim 5, characterized in that at least one of the enlargement side and the reduction side of the fifth lens (5) is a concave surface. 7. The optical projection system according to claim 5, characterized in that, the effective focal length f5 of the fifth lens (5) satisfies -37.7mm<f5<-30.1mm; the effective focal length f5 of the eighth lens (8) The focal length f8 satisfies 10.3mm<f8<16.28mm. 8. The optical projection system according to claim 3 or 5, characterized in that the distance from the third lens (3) to the diaphragm (12) is the same as the distance from the fourth lens (4) to the light The ratio range of the distance of the diaphragm (12) is 1-5. 9. The optical projection system according to claim 1, characterized in that, the optical projection system further comprises a vibrating mirror (13), and the vibrating mirror (13) is arranged on the second lens group away from the light One side of appendix (12). 10. A projection device, characterized in that the projection device comprises the optical projection system according to any one of claims 1-9.

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