KR20060117133A - Optical apparatus of reflection type in the projection system and filter holder - Google Patents

Abstract

A reflective optical device and a filter holder of a projection system are provided to filter UV(Ultra Violet) rays of light projected to the reflective optical device using a UV filter. A reflective optical device of a projection system includes a light source, a UV filter(40) for filtering UV rays of light emitted from the light source, a single notch filter(30) for filtering miscellaneous light of the light emitted from the light source, a dichroic mirror(10) for splitting colors of incident light, first, second and third beam splitters(13,19,23) for transmitting or reflecting light in response to the incident direction of the light, and first and second polarization converters(11,12) for performing polarization conversion on green light and red light. The reflective optical device further includes first, second and third panels(15,17,25), quarter wave plates(14,16,24) respectively located between the panels and the beam splitters, third and fourth polarization converters(18,21) placed between the first and second beam splitter and between the second and third beam splitters, and a fifth polarization converter located between the second beam splitter and a projection lens to attenuate reflective waves inputted through the projection lens along a reverse path. Light transmitted or reflected by the first, second and third beam splitters is inputted to and reflected by the first, second and third panels.

Description

Optical apparatus of reflection type in the projection system and Filter holder}

1 is a block diagram showing a reflective optical device of a conventional projection system.

2 is an exploded perspective view showing a filter holder of a conventional projection system.

3 is a block diagram showing a reflective optical device of the projection system according to the present invention.

4 is a perspective view showing the filter holder of the projection system according to the present invention.

5 is a cross-sectional view showing the filter holder of the projection system according to the present invention.

<Explanation of symbols for the main parts of the drawings>

30: single notch filter 40: UV filter

50: dichroic mirror 51, 52, 58, 61, 62, 70: polarization conversion element

53,59,63: Beam splitter 54,56,64: 1/4 wave plate

55: red panel 57: green panel

65 Blue panel 60 Projection lens

100: filter holder

The present invention relates to a reflective optical device and a filter holder of a projection system, and more particularly, to heat the reflective optical device to a filter holder which is supported by a single notch filter for filtering out the glare of the reflective optical device. The present invention relates to a reflective optical device and a filter holder of a projection system provided with an ultraviolet filter to filter ultraviolet rays.

Recently, the use of high resolution projectors and projections is increasing. In particular, as the commercialization of digital television is imminent, the use of projection television having a large screen with high resolution is increasing. Therefore, in order to realize a high resolution large screen, screen brightness has emerged as a very important variable.

In general, in the case of a three-panel type, a high light utilization efficiency and a vivid image can be realized, and thus a lot of attention is being focused on portable projector applications through a compact configuration. According to this trend, there is a strong demand for an optical system capable of realizing bright and clear images by maximizing light utilization efficiency while using the same lamp. Therefore, polarized light is used to express gray levels in a system using a transmissive high temperature poly or a reflective liquid crystal on silicon (LCoS) micro display.

A projection system having a conventional reflective optical apparatus as described above will be described with reference to FIG. 1 is a block diagram showing a reflective optical device of a conventional projection system. Referring to the drawings, a single notch filter 30 for blocking the yellow light close to the concentration of light projected from the light source; A dichroic mirror 10 for color separation of the light source; First to third beam splitters 13, 19, and 23 for transmitting or reflecting according to the incident direction of the light source; A first polarization converting element (11) and a second polarization converting element (12) installed between the dichroic mirror (10) and the first beam splitter (13); First to third panels 15, 17, and 25 through which light sources transmitted or reflected by the first and third beam splitters 13 and 23 are incident and reflected; Quarter wave plates 14, 16 and 24 provided between the panels 15, 17 and 25 and the beam splitters 13, 19 and 23; The first and second beam splitters 13 and 19 and the second and third beam splitters 19 and 23 are configured to include third and fourth polarization conversion elements 18 and 21.

Here, the filter holder is provided to install the single notch filter, the filter holder will be described with reference to FIG.

2 is an exploded perspective view showing a filter holder of a conventional projection system. Referring to the drawings, the filter holder 32 is installed between the light source and the dichroic mirror 10 to support the single notch filter 30. The filter holder 32 supports a single notch filter 30 for filtering out yellow light close to the eccentric light from the light projected from the light source, so that the light projected from the light source can pass through the filter holder 32. An open receiving surface 36 is formed, and the single notch filter 30 is positioned on the receiving surface 36. In addition, the fixing piece 34 protruding from the periphery of the receiving surface 36 is bent toward the single notch filter 30 so that the single notch filter 30 can be stably positioned on the receiving surface 36. .

Looking at the operation of the projection system having a conventional reflective optical device having the configuration as described above, the single notch filter 30 filters the yellow light close to the concentration of light projected from the light source to the dyke It will be projected onto the lower wing mirror. The dichroic mirror 10 separates the color of the incident light source. That is, red and green light sources (S waves) are reflected from the incident light source, and blue light sources (P waves) are transmitted.

The light source reflected by the dichroic mirror 10 is an S wave, and a red light source of an S wave is converted into a P wave in the first polarization conversion element 11, and transmitted through the second polarization conversion element 12. Incident at the first beamsplitter 13. The P wave incident on the first beam splitter 13 is transmitted and incident (signal on) to the red panel which is the first panel 15 through the quarter wave plate 14. The signal incident on the first panel 15 is reflected through the first panel 15 and the quarter wave plate 14 to be converted into S-waves, and reflected by the first beam splitter 13, so that the third polarization converting element Converted to P wave via (18). The red light source converted from the third polarization conversion element 18 into the P wave is transmitted through the second beam splitter 19 to be formed on the screen through the projection lens 20.

The green light source of the S-waves is transmitted through the first and second polarization conversion elements 11 and 12 to be incident on the first beam splitter 13 and is reflected thereon, and the second panel is provided through the quarter wave plate 16. It is incident (signal on) to the green panel (17). The light source reflected by the second panel 17 and the quarter wave plate 16 is converted into P waves, and transmitted through the first beam splitter 13, and the transmitted P waves are transmitted by the third polarization converting element 18. The second beam splitter 19 passes through the projection lens 20 and is formed on the screen.

On the other hand, the blue light source transmitted from the dichroic mirror 10 is a P wave, and is converted into an S wave in the second polarization conversion element 62, and the blue light source converted into the S wave is reflected by the third beam splitter 23. And incident (signal on) to the blue panel, which is the third panel 25, through the quarter-wave plate 24. S-waves incident on the third panel 25 are reflected again and converted into P-waves through the quarter-wave plate 24 to pass through the third beam splitter 23, and the transmitted P-waves are the fourth polarization converting elements 21. ) Is converted into an S wave and reflected by the second beam splitter 19 to be formed on the screen through the projection lens 20.

The first to third beam splitters 13, 19, and 24 transmit P waves and reflect S waves, and the first polarization conversion element 11 is a red light source suppression layer, and P waves are S waves. The S wave is converted into a P wave. The third polarization converting element 18 serves as a suppression film of red and blue light sources, converting P waves into S waves and S waves into P waves. The fourth polarization converting element 21 is a blue light source suppressing film, which converts P waves into S waves and S waves into P waves.

However, the light projected by the reflective optical device having the above-described configuration is also projected with ultraviolet light which causes photochemical action of the reflective optical device, thereby causing a problem in the reflective optical device.

On the other hand, an ultraviolet filter should be provided to filter the ultraviolet light to the light projected by the reflective optical device. However, since the conventional reflective optical device has a very complicated mechanical structure as described above, the reflective type optical device is used to install the ultraviolet filter. The redesign of the optics is inevitable.

The present invention is to solve the above problems, the reflection optical device of the projection system is provided with an ultraviolet filter to filter out the ultraviolet light causing the photochemical action on the reflective optical device of the light source projected by the reflective optical device. The purpose is to provide.

In addition, an object of the present invention is to provide a filter holder of a reflective optical device of a projection system that can be installed together with the ultraviolet filter in a holder provided with a single notch filter to install an ultraviolet filter in the reflective optical device.

According to the technical idea of the present invention for achieving the above object, a light source, an ultraviolet filter for filtering out ultraviolet light from the light projected from the light source, a single notch filter for filtering out the light of the light projected from the light source, A dichroic mirror for color separation of the incident light source, first to third beam splitters that transmit or reflect the light source according to the incident direction of the light source, and installed between the dichroic mirror and the first beam splitter and being red A first polarization conversion element and a second polarization conversion element for polarizing conversion with respect to the green light source, first to third panels in which light sources transmitted or reflected by the first and third beam splitters are incident and reflected, and each panel And a quarter wave plate provided between the beam splitter and the third and fourth polarization conversion elements provided between the first and second beam splitters and the second and third beam splitters. It is achieved by a reflective optics of a projection system that is provided between a beam splitter and a projection lens and includes a fifth polarization conversion element for attenuating reflected waves incident on the reverse path through the projection lens.

Here, the ultraviolet filter is preferably installed in front of the single notch filter.

On the other hand, according to another technical idea of the present invention for achieving the above object, the light incident from the light source is separated into R, G, B, reflected or transmitted to each panel, and then synthesized to illuminate the screen through the projection lens A reflective optical device comprising: an ultraviolet filter disposed between a light source and a dichroic mirror to filter out ultraviolet rays from the light projected from the light source, and a light beam disposed between the light source and the dichroic mirror and projected from the light source It is achieved by a filter holder of a reflective optical device for a projection system, including; a single notch filter for filtering out light and a filter holder provided to be integrally interposed between the ultraviolet filter and the single notch filter.

The filter halter may include an open receiving surface, a first bent piece projecting from the periphery of the receiving surface, and one end of which is bent, and exposed to the receiving surface by being interposed between the receiving surface and the first bent piece. An ultraviolet filter for filtering ultraviolet rays among the projected light, a second bending piece protruding from the periphery of the receiving surface, and one end of which is bent, and among the light projected from the light source interposed between the first bending piece and the second bending piece It is preferable to include a single notch filter for filtering the filter.

In addition, it is preferable that one end of the first bent piece and the second bent piece is bent such that elastic force is exerted so as not to apply excessive pressure to the ultraviolet filter and the single notch filter.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected about the part same as a conventional structure among the content of this invention.

3 is a block diagram showing a reflective optical device of the projection system according to the present invention. Referring to the drawings, a light source for generating light,

An ultraviolet filter (40) disposed between the light source and the dichroic mirror (10) to filter out ultraviolet rays from the light projected from the light source; A single notch filter 30 for filtering, a dichroic mirror 50 for color separation of the light source, and first to third beam splitters 53, 59, and 63 for transmitting or reflecting the light source according to the incident direction of the light source. And a first polarization converting element 51 and a second polarization converting element 52 which are provided between the dichroic mirror 50 and the first beam splitter 13 to convert to the desired polarization. First to third panels 55, 57, 65, and each of the panels 55, 57, 65, and the beam splitter 53 to which light sources transmitted or reflected by the third beam splitters 53 and 63 are incident and reflected. Quarter wave plates 14, 16, and 24 provided between the second and third beam splitters 13 and 19, and the second and third beam splitters 19 and 23, respectively. The third and fourth polarization conversion elements 58 and 61 disposed between the second and fourth polarization conversion elements 58 and 61, and the fifth and fourth polarization conversion elements 58 and 61 between the second beam splitter 59 and the projection lens 60 to convert the reflected waves reflected from the projection lens into S waves. It consists of the polarization conversion element 70.

Referring to the accompanying drawings, the optical system of the projection system according to the embodiment of the present invention as described above is as follows. Ultraviolet rays, which cause photochemical reactions among the light projected from the light source, are first filtered out by the ultraviolet filter 40 and sent to the dichroic mirror 50, and to the single notch filter 30 of the light projected from the light source. As a result, the yellow light close to the light is filtered and projected onto the dichroic mirror 50. The dichroic mirror 50 separates the color of the incident light source. That is, red and green light sources (S waves) are reflected from the incident light source, and blue light sources (P waves) are transmitted.

The light source reflected by the dichroic mirror 50 is S-wave, and the red light source of the S-wave is converted into P-wave by the first polarization conversion element 51, and passes through the second polarization conversion element 52 to pass the first light. The light is transmitted through the beam splitter 53 and incident (signal on) to the red panel which is the first panel 55 through the quarter wave plate 54. The signal incident on the first panel 55 is reflected through the first panel 55 and the quarter wave plate 54 to be converted into S-waves, and is reflected by the first beam splitter 53, so that the third polarization converting element Converted to P wave via (58). The red light source converted into the P wave in the third polarization conversion element 58 is transmitted through the second beam splitter 59. At this time, the P wave transmitted through the second beam splitter 59 is converted into left circularly polarized light by the fifth polarization converting element 70 and is formed on the screen through the projection lens 60. Here, the second beam splitter 59 sums and outputs R, G, and B color signals incident on different paths.

In addition, the green light source of the S-wave reflected by the dichroic mirror 50 passes through the first and second polarization conversion elements 51 and 52 and is incident and reflected by the first beam splitter 53. The green light source enters (signals on) the green panel which is the second panel 57 through the quarter wave plate 56. The light source reflected by the second panel 57 and the quarter-wave plate 56 is converted into P waves and transmitted through the first beam splitter 53, and the transmitted P waves are transmitted by the third polarization conversion element 58. The light is transmitted through the second beam splitter 59. At this time, the P wave transmitted through the first beam splitter 59 is converted into left circularly polarized light by the fifth polarization converting element 70 and is formed on the screen through the projection lens 60.

On the other hand, the blue light source transmitted from the dichroic mirror 50 is P wave, and the second polarization conversion element 62 is converted into S wave, and the blue light source converted into S wave is reflected by the third beam splitter 63. Then, the light is incident (signal on) to the blue panel, which is the third panel 65, through the quarter-wave plate 64. S-waves incident on the third panel 65 are reflected again and converted into P-waves through the quarter-wave plate 64 to pass through the third beam splitter 63, and the transmitted P-waves are fourth polarization converting elements 61. ) Is converted into an S wave and reflected by the second beam splitter 59. In this case, the S-waves reflected by the second beam splitter 59 pass through the fifth polarization conversion element 70 and are converted into left circularly polarized light, and are formed on the screen through the projection lens 60.

In addition, the first to third beam splitters 53, 59, and 63 have characteristics of transmitting P waves and reflecting S waves, and the first polarization converting element 51 is a red light source suppressing film. The wave is converted into an S wave, and the S wave is converted into a P wave. The third polarization converting element 58 is a suppression film of red and blue light sources, in which P waves are converted into S waves and S waves are converted into P waves. The fourth polarization converting element 61 is a blue light source suppressing film, in which P waves are converted into S waves and S waves are converted into P waves. Further, the first to third panels 55, 57 and 65 are preferably reflective liquid crystal panels.

In addition, the fifth polarization conversion element 70 converts the P-wave transmitted from the second beam splitter 59 into left circularly polarized light, and converts right circularly polarized light, which is a light source reflected by the reverse path through the projection lens 60, to S-wave. Let it be. The fifth polarization conversion element 70 is an achromatic lens, and the achromatic lens is a lens for correcting chromatic aberration of two colors, and is made of, for example, an Achromatic Quarter Wave Plate (AQWP). .

The fifth polarization converting element 70 converts the reflected wave, which is the right circularly polarized light incident in the reverse path, into the S wave, thereby reflecting the light source reflected through the projection lens 60, that is, the reflected red light source and green light source Rx and Gx. ) Is changed from the right circularly polarized signal to the S wave, thereby being reflected without being transmitted by the second beam splitter 59. The S-waves reflected by the second beam splitter 59 are transmitted by the fourth polarization conversion element 61 and reflected by the third beam splitter 63. This solves the problem that the light source reflected from the projection lens is incident back to the panel (e.g., red panel, green panel), resulting in attenuation of the reflected wave, while the light projected from the light source and incident on the dichroic mirror In this case, ultraviolet rays are filtered to prevent photochemical reactions from occurring in the reflective optical device, and yellow light close to stray light is filtered, so that high quality images can be generated.

On the other hand, since the light incident on the dichroic mirror 50 from the light source includes ultraviolet light and stray light, the ultraviolet filter 40 and the single notch filter 30 filter the light source and the dichroic mirror to filter the light. Bar 50 is installed between, the filter holder 100 is provided so that the UV filter 40 and the single notch filter 30 can be interposed integrally.

4 is a perspective view showing a filter holder of the projection system according to the present invention, Figure 5 is a cross-sectional view showing a filter holder of the projection system according to the present invention. Referring to the drawings, the filter holder 100 is provided so as to interpose the UV filter 40 and the single notch filter 30 integrally, for this purpose, the filter holder 100 is a projected light source A plate installed in a vertical direction from the plate, a receiving surface 110 open to the plate to allow light projected from the light source to pass therethrough, and a first bent piece protruding from the periphery of the receiving surface 110 and bent at one end thereof. 120 is provided, and the ultraviolet filter 40 is interposed between the receiving surface 110 and the first bent piece 120 of the plate. In addition, a second bending piece 130 protruding from the periphery of the receiving surface 110 and extending from the first bending piece 120 and having one end is provided, so that the first bending piece 120 and the second bending piece are provided. The single notch filter 30 is interposed between the pieces 130.

Here, one end of the first bent piece 120 and the second bent piece 130 is bent toward the receiving surface 110, one end of the first bent piece 120 and the second bent piece 130, respectively UV filter 40 and the single notch filter 30 is formed to be in close contact. That is, one end of the first bent piece 120 of the ultraviolet filter 40 is bent to closely contact the receiving surface 110 side, and one end of the second bent piece 130 is formed of the single notch filter 30. It is bent so that it may be in close contact with the 1st bending piece 120 side. To this end, one end of the first bent piece 120 and the second bent piece 130 is shown in the figure so that the elastic force is exerted within the limit that does not apply excessive pressure to the ultraviolet filter 40 and the single notch filter 30 Is bent as shown.

By the filter holder according to the present invention as described above, it is possible to interpose the ultraviolet filter and the single notch filter integrally, without having to provide a separate structure in the reflective optical device to install the ultraviolet filter. In addition, one end of the first bent piece and the second bent piece is bent to exert an elastic force, so that each of the ultraviolet filter and the single notch filter are held in close contact with each other, so that the ultraviolet filter and the single notch filter are not excessively pressured. It can prevent deformation and breakage of filter and single notch filter.

The reflective optical device and the filter holder of the projection system according to the present invention improve the chess contrast through the attenuation of the reflected wave by reflecting the light source reflected by the reverse path from the projection lens to the other path after polarization conversion. In addition, it is possible to block the ultraviolet light causing the photochemical action to the reflective optical device to provide a reflective optical device with improved reliability.

In addition, since the ultraviolet filter and the single notch filter can be interposed integrally, the redesign of the reflective optical device for installing the ultraviolet filter in the reflective optical device having a very complicated and precise mechanical structure is unnecessary.

On the other hand, the present invention is not limited only to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, the technical idea that such modifications and variations are also included in the claims Should be seen.

Claims (5)

Light source; An ultraviolet filter for filtering ultraviolet rays among the light projected from the light source; A single notch filter for filtering out light from the light projected from the light source; A dichroic mirror for color separation of an incident light source; First to third beam splitters that transmit or reflect the light source according to the incident direction of the light source; A first polarization conversion element and a second polarization conversion element disposed between the dichroic mirror and the first beam splitter to polarize the red and green light sources; First to third panels through which light sources transmitted or reflected by the first and third beamsplitters are incident and reflected; A quarter wave plate disposed between each panel and the beam splitter; Third and fourth polarization conversion elements disposed between the first and second beamsplitters and the second and third beamsplitters; And And a fifth polarization converting element disposed between the second beam splitter and the projection lens to attenuate the reflected wave incident through the projection lens in a reverse path through the projection lens. The method of claim 1, Reflective optical device of the projection system, characterized in that the ultraviolet filter is installed in front of the single notch filter. In the reflective optical device in which the light incident from the light source is separated into R, G, and B, reflected or transmitted to each panel, and then synthesized to shine onto the screen through the projection lens. An ultraviolet filter disposed between the light source and the dichroic mirror to filter ultraviolet rays from the light projected from the light source; A single notch filter disposed between the light source and the dichroic mirror to filter out light from the light projected from the light source; And a filter holder provided to integrally interpose the UV filter and the single notch filter. The method of claim 3, wherein An open receiving surface; A first bent piece protruding from the periphery of the receiving surface and having one end bent; An ultraviolet filter interposed between the receiving surface and the first bent piece to filter ultraviolet rays from the light projected from the light source by being exposed to the receiving surface; A second bent piece protruding from the periphery of the receiving surface and having one end bent; And a single notch filter interposed between the first bent piece and the second bent piece to filter out the stray light from the light projected by the light source. The method of claim 4, wherein And one end of the first bent piece and the second bent piece so that the elastic force is exerted so as not to apply excessive pressure to the ultraviolet filter and the single notch filter.

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