JP2009063837A - Multiple primary color digital light dividing and coupling system and method, and digital projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple primary color digital light dividing and coupling system in which more primary colors are used for formation of an image in order to improve image quality such as precision of saturation (depth), and to provide a multiple primary color digital light dividing and coupling method. <P>SOLUTION: The multiple primary color digital light dividing and coupling system comprises: a dichroic device 406 which divides incident light beam into a first light beam 408 in a first wavelength region and a second light beam 410 in a second wavelength region; a first polarized beam splitter (PBS) 412 which divides and generates a first polarized beam having a first polarized state from the first light beam; a second PBS 416 which divides and generates a second polarized beam having a second polarized state from the second light beam; a first reflection type display panel 414 which receives the first polarized beam and reflects a first image information set corresponding to a plurality of primary colors respectively; and a second reflection type display panel 418 which receives the second polarized beam and reflects a second image information set corresponding to a plurality of other primary colors respectively; and a post stage PBS 420 which receives first and second image information sets, couples them and forms image light beams. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image projection technique. More specifically, the present invention relates to a technique for forming an image using many primary colors in order to effectively improve image quality.

  A characteristic of a reflective display panel such as LCOS (liquid crystal on silicon) is that most of the drive devices are formed on a lower substrate, and a liquid crystal layer is disposed between the lower substrate and the upper substrate. Light from the light source enters the lower substrate from the upper substrate and is reflected by the reflective layer of the lower substrate. Therefore, the reflected light is not shielded by the driving device, and thereby the light utilization efficiency can be improved.

  A projection type display device can be constructed using a reflective LCOS. FIG. 1 is a diagrammatic configuration diagram of a conventional projection display device. Referring to FIG. 1, the white light beam 100 is incident on the dichroic mirror 102. The dichroic mirror splits the incident light into a blue light beam 106 and a red-green mixed light beam 104 based on the color tone of the light. A reflection mirror 108 is disposed in the optical path of the red-green mixed light beam 104 and reflects the red-green mixed light beam 104 so as to travel to a desired path. Next, the mixed red-green light beam 104 is split by the dichroic mirror 110 into a red light beam 112 and a green light beam 114. The green light beam 114 is incident on a polarization beam splitter (PBS) 116, for example. The polarization beam splitter (PBS) 116 reflects, for example, light in the S-type polarization state and transmits light in the P-type polarization state. Therefore, the portion of the green light beam 114 in the S-type polarization state is turned by 90 ° and enters the LCOS 118. The drive device for each pixel of the LCOS 118 drives the angular rotation of the liquid crystal within each pixel. Therefore, the incident light in the S-type polarization state in the green light is reflected by the LCOS 118, and thereafter, the direction is rotated when driving each pixel, and a portion having the P-type polarization state is generated. Therefore, the portion of the reflected green light in the P-type polarization state is transmitted through the same PBS 116, and the green light image 120 whose intermediate tone level is determined by the degree of the P-type polarization state generated by the amount of rotation of the liquid crystal is obtained.

  Furthermore, according to this mechanism, the red light beam 112 generates a red image 126 via the PBS 122 and the LCOS 124. Similarly, according to this mechanism, blue light beam 106 produces blue image 134 via PBS 130 and LCOS 132. A green image 120, a red image 126, and a blue image 134 are combined by a light coupling mirror 136 to form a color image 138, and further using a projection unit 140, for example, amplifying the image to another image 142, The image 142 is projected on a display screen (not shown).

  The design of the conventional projection display device shown in FIG. 1 depends on the structure of three individual monochromatic LCOS panels in the three primary colors, and this entire projection system requires multiple light paths and is therefore complex. . FIG. 2 is a diagrammatic illustration showing the structure of a conventional multicolor LCOS panel. Referring to FIG. 2, in the reflective display panel 202 having three primary colors of red, green, and blue, each pixel generates three intermediate tone levels corresponding to red, green, and blue, respectively. Has sub-pixels. That is, after the incident light 204 enters the PBS 200, for example, light in a certain polarization state is reflected on the reflective display panel 202, and the polarization state of each sub-pixel is controlled and changed based on a desired intermediate tone level. Thus, the light enters and passes through the PBS 200 and reaches the projection lens 206. Therefore, an integrated display panel can be obtained.

  The reflective display panel 202 described above still still uses red, green and blue as primary colors to form the desired image color. FIG. 3 is a diagrammatic cross-sectional view of a conventional pixel structure. Referring to FIG. 3, three pixel electrodes 302R, 302G, and 302B corresponding to red, green, and blue are provided on the substrate 300, respectively. These pixel electrodes 302R, 302G, and 302B are covered by an absorption layer 304. The optical films 306R, 306G, and 306B corresponding to red, green, and blue reflect red light, green light, and blue light, respectively. These optical films 306R, 306G and 306B are covered by an alignment layer 308. The electrode layer 314 and the alignment layer 312 are disposed on another substrate 316. The liquid crystal layer 310 is disposed between the alignment layer 308 and the alignment layer 312. As a result, the pixel is constituted by the three primary colors of red, green and blue, and the intermediate tone level of each color can be controlled to obtain a desired color.

  In the above method, the color light is composed of red, green, and blue colors. Therefore, if the range of the intermediate tone level value is insufficient, the saturation (darkness) of the image is affected. Those skilled in the art continue to search for a technique for improving the accuracy of the saturation (darkness) of an image so as to improve the image quality.

  It is an object of the present invention to obtain a multi-primary digital light splitting and combining system and method that uses more primary colors to form an image, at least to improve saturation (darkness) accuracy.

  Another object of the present invention is to obtain a digital projector using the above light splitting and combining system for forming an image in order to improve the image quality of the projector.

  The present invention provides a multi-primary digital light splitting and combining system that receives an incident light beam, which is incident on a first light beam in a first wavelength range and a second light in a second wavelength range. A dichroic device for dividing the beam is provided. The wavelength value in the first wavelength range is assumed to be larger than the wavelength value in the second wavelength range. The first polarization beam splitter (PBS) receives the first light beam, and splits and generates a first polarization beam having a predetermined first polarization state from the first light beam. The second PBS receives the second light beam, and splits and generates a second polarized beam having a predetermined second polarization state from the second light beam. The first reflective display panel receives the first polarized beam and reflects the first image information set corresponding to each of the plurality of primary colors. The second reflective display panel receives the second polarized beam and reflects the second image information set corresponding to each of the plurality of primary colors. The post-stage PBS receives and combines the first and second image information sets to form an image light beam.

  In the multi-primary color digital light splitting and combining system according to the embodiment of the present invention, the first wavelength range is, for example, about 650 nm to 700 nm, and the second wavelength range is about 400 nm to 650 nm.

  In the multi-primary color digital light splitting and combining system according to the embodiment of the present invention, the first image information set includes, for example, three individual image information of red, yellow and green, and the second image information set includes magenta and blue And three pieces of individual image information of cyan.

  In the multi-primary digital light splitting and combining system according to the embodiment of the present invention, the first image information set includes, for example, individual image information of at least two primary colors, and the second image information set is an individual image of at least two primary colors. It shall include image information. Further, the first wavelength region and the second wavelength region constitute the entire wavelength region of visible light.

  In the multi-primary digital light splitting and combining system according to the embodiment of the present invention, the first and second reflective display panels each have a plurality of pixels constituting a pixel array. Each pixel has a plurality of sub-pixels corresponding to the primary colors.

  The present invention also provides a digital projector comprising the multi-primary color digital light splitting and combining system, the incident light source system, and the projection lens system described above.

  The present invention also provides a multi-primary digital light splitting and combining method that receives an incident light beam, which is divided into a first light beam in a first wavelength region and a second wavelength. Locating a dichroic device for splitting into a second light beam in the region. The wavelength value in the first wavelength range is assumed to be larger than the wavelength value in the second wavelength range. In addition, the first light beam is received, the first polarized beam having a predetermined first polarization state is split from the first light beam, the second light beam is received, and the second light beam is received from the second light beam. A second polarized beam having two polarization states is split. The first polarized beam is received by the first reflective display panel and reflects the first image information set corresponding to each of the plurality of primary colors. The second polarized light beam is received by the second reflective display panel, and the second image information set corresponding to each of the plurality of primary colors is reflected. The first and second image information sets are combined to form an image light beam.

  In order to achieve the above and other objects, the features and advantages of the present invention, a preferred embodiment, are described in detail below with reference to the drawings.

It is to be understood that the foregoing general description and the following detailed description are exemplary and are intended to explain the claimed invention in greater detail.
The accompanying drawings are incorporated to form part of this specification for a better understanding of the invention. The drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

  The present invention forms an image using many primary colors in order to improve at least the saturation (darkness). Preferably, in the present invention, for example, a beam having a wavelength component including components of red (R), yellow (Y) and green (G), and components of magenta (M), blue (B) and cyan (C) are included. Another beam having a wavelength component is used. Each of the six primary colors is extracted by filtering and controls their intermediate tone level values. Finally, the individual images corresponding to the six primary colors are combined to form one image. Therefore, the image quality is improved. Hereinafter, the present invention will be described by way of examples, but the present invention is not limited thereto.

  FIG. 4 is a schematic diagram of a digital projector configured by a multi-primary color digital light splitting and combining system according to an embodiment of the present invention. Referring to FIG. 4, the light source system includes, for example, a light source unit 400, an optical device 402, and a lens 404. For example, white light is provided as the light source unit 400. The optical device 402 is used to adjust the uniformity of white light. Lens 404 is used to introduce the generated light into a multi-primary digital light splitting and combining system.

  The multi-primary digital light splitting and combining system includes, for example, a dichroic device 406, polarizing beam splitting devices 412 and 416, a reflective display panel 414 and 418, and a polarizing beam splitting device 420. The dichroic device 406 receives incident light and splits the incident light into two light beams, for example, a first light beam 408 having a first wavelength region and a second light beam 410 having a second wavelength region. For example, it is assumed that the wavelength value in the first wavelength range is larger than the wavelength value in the second wavelength range. The first wavelength range is, for example, 650 nm to 700 nm and includes red light, yellow light, and green light. The second wavelength range is, for example, 400 nm to 650 nm and includes magenta light, blue light, and cyan light.

  Here, in general, the first wavelength range includes at least two primary colors, and similarly, the second wavelength range includes at least two primary colors. The first wavelength range and the second wavelength range constitute the entire wavelength range of visible light. For each primary color, image information corresponding to each color can be generated together with the subsequent display device. Details will be described later.

  The divided first light beam 408 enters the polarization beam splitting device 412. The polarization beam splitting device 412 has a feature of reflecting light of a specific polarization state and transmitting light of another polarization state, but the design in an actual device is not limited to this specific structure. In this embodiment, the polarization beam splitting device 412 is a rectangular prism, can obtain a polarization spectroscopy effect by using a fine structure on an inclined surface, and obtain a polarization spectroscopy effect on the first light beam 408 in at least the first wavelength region. be able to. Similarly, the split second light beam 410 is incident on a polarization beam splitting device 416 similar to the polarization beam splitting device 412.

  In one embodiment, the portion of the first light beam 408 having a predetermined first polarization state is introduced into the reflective display panel 414 by being reflected by the reflective display panel 414, for example. On the other hand, a portion of the light beam having a predetermined second polarization state in the second light beam 410 is introduced into the reflective display panel 418 by being reflected by the reflective display panel 418, for example. The reflective display panel 414 is used to generate individual image information of red light, yellow light, and green light. The reflective display panel 418 is used to generate image information of magenta light, blue light, and cyan light. The predetermined first polarization state and the predetermined second polarization state described above are determined on the basis of the display mechanism of the subsequent reflective display panels 414 and 418, and may be the same or different. Note that you can.

  In this embodiment, the reflective display panel 414 converts the desired intermediate tone level value to another polarization state so as to pass through the polarization beam splitting device 412. However, when the reflective display panel 414 is configured to receive light in a certain polarization state that is transmitted through the polarization beam splitting device 412, this polarization state of the image information is reflected by the polarization beam splitting device 412. In other words, the desired polarization state and the polarization state to be reflected vary depending on the actually designed mechanism, and the illustrated embodiment is merely one example.

  The structure of the reflective display device 414 is shown, for example, in FIG. Referring to FIG. 5, pixel electrodes 502 R, 502 Y, and 502 G corresponding to red, yellow, and green (R, Y, and G) are provided on the substrate 300. The pixel electrodes 502R, 502Y, and 502G are covered by the absorption layer 504 so that undesirable light can be absorbed. The three optical films 506R, 506Y, and 506G corresponding to red, yellow, and green reflect, for example, red light, yellow light, and green light, and the transmitted light is absorbed by the absorption layer 504. The alignment layers 508 cover the optical films 506R, 506Y, and 506G. Electrode layer 514 and alignment layer 512 are disposed on another substrate 516. A liquid crystal layer 510 is disposed between the alignment layer 508 and the alignment layer 512. One pixel is composed of three sub-pixels with three primary colors of red light, yellow light and green light, and these sub-pixels are generally known for changing the polarization state corresponding to each primary color, for example. Individual image information corresponding to three primary colors having intermediate tone level values obtained by the mechanism is generated. Further, FIG. 6 is a diagrammatic configuration diagram of the reflective display panel 418. Referring to FIG. 6, FIG. 6 is the same as FIG. 5, except that the optical films 506M, 506B, and 506C are three pieces of individual image information corresponding to magenta light, blue light, and cyan light.

  Next, the polarized beams transmitted through the polarized beam splitting devices 412 and 416 enter the subsequent PBS 420, and the primary color individual image information is combined by the light splitting and combining interface 422 to form the image light beam 424. Thereafter, the image light beam 424 is projected to a position where an image is to be displayed by a projection system such as a projection mirror 426.

  Although a six primary color configuration is shown as an example, this is not the only choice. FIG. 7 is a schematic diagram of a multi-primary digital light splitting and combining system as another embodiment of the present invention. This multi-primary digital light splitting and combining system includes, for example, a dichroic device 700, polarizing beam splitting devices 708 and 710, reflective display panels 706 and 712, and a polarizing beam splitting device 714.

  The dichroic device 700 receives the incident light beam 702 and splits the incident light beam 702 into two light beams 704 and 705. The light beam 704 has a first wavelength range, and the light beam 705 has a second wavelength range. For example, the wavelength value of the first wavelength range is larger than the wavelength value of the second wavelength range. The first wavelength range includes light of at least two primary colors. The second wavelength range includes light of at least two primary colors. The first wavelength range and the second wavelength range constitute the entire wavelength range of visible light. The two light beams 704 and 705 are incident on polarization beam splitting devices 708 and 710, respectively. A light beam having a predetermined polarization state is generated by polarized beam splitting devices 708 and 710, which are introduced into reflective display panels 706 and 712, respectively. The reflective display panels 706 and 712 control the rotation angle of the liquid crystal molecules to change the polarization state to the intermediate tone level value required by the corresponding primary color. When the light splitting effect is generated in the light introduced into the reflective display panels 706 and 712 by the polarization beam splitting devices 708 and 710, the light is divided into individual image information corresponding to a plurality of primary colors, and also corresponding to the plurality of primary colors. The individual image information to be combined with the image light beam. Here, light coupling occurs at interface 716 by subsequent PBS 714 to obtain image light beam 718.

  From a method standpoint, the present invention also provides a multi-primary digital light splitting and combining method. An optical splitting and combining method adapted to the above-described apparatus receives, for example, incident light and splits the incident light into a first light beam having a first wavelength range and a second light beam having a second wavelength range. A step of preparing a dichroic device is included, and the wavelength value of the first wavelength range is larger than that of the second wavelength range. In addition, the first light beam is received, a first polarized beam having a predetermined first polarization state is divided and generated, the second light beam is received, and a second polarized beam having a predetermined second polarization state is received. Split and generate. The first polarized beam is received by the first reflective display panel, and the first image information set corresponding to each of the plurality of primary colors is reflected by the first reflective display panel. The second polarized beam is received by the second reflective display panel, and the second image information set corresponding to each of the plurality of primary colors is reflected by the second reflective display panel. The first and second image information sets are combined to form an image light beam.

  Conventionally, since a desired color is formed using the three primary colors of red, green, and blue, if the intermediate color tone of each primary color is determined, the coloring effect is poor. In the design of the present invention that uses three or more primary colors of red, green, and blue to form a desired color, even if the intermediate tones of the primary colors are the same, the color change is sufficient, and therefore the image quality Will improve.

  The preferred embodiments of the present invention have been described above, but these embodiments do not limit the present invention. Those skilled in the art can make changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention extends to the appended claims and their equivalents.

It is a diagrammatic block diagram of a conventional projection display device. FIG. 2 is a diagrammatic configuration diagram of a conventional multicolor LCOS panel. 1 is a diagrammatic cross-sectional view of a conventional pixel structure. FIG. 1 is a diagrammatic configuration diagram of a digital projector configured by a multi-primary color digital light splitting and combining system according to an embodiment of the present invention. FIG. FIG. 5 is a diagrammatic explanatory view showing a structure of a reflective display device 414 shown in FIG. 4. FIG. 5 is a diagrammatic explanatory view showing a structure of a reflective display device 418 shown in FIG. 4. 1 is a diagrammatic block diagram of a multi-primary digital light splitting and combining system according to an embodiment of the invention.

Explanation of symbols

100 White light beam 102 Dichroic mirror 104 Red-green mixed light beam 106 Blue light beam 108 Reflective mirror 110 Dichroic mirror 112 Red light beam 114 Green light beam 116 Polarizing beam splitter (PBS)
118 LCOS
120 Green light image 122 PBS
124 LCOS
126 Red image 128 Reflective mirror 130 PBS
132 LCOS
134 Blue image 136 Optical coupling mirror 138 Color image 140 Projection unit 142 Image 200 PBS
202 Reflective display panel 204 Incident light 206 Projection lens 300 Substrate 302 Electrode 304 Absorbing layer 306 Optical film 308 Alignment layer 310 Liquid crystal layer 312 Alignment layer 314 Electrode layer 316 Substrate 400 Light source unit 402 Optical device 404 Lens 406 Dichroic device 408 First light Beam 410 Second light beam 412 Polarized beam splitting device (PBS)
414 Reflective display panel 416 Polarized beam splitting device (PBS)
418 Reflective display panel 420 Polarized beam splitting device (PBS)
422 Post-stage PBS
424 Image light beam 426 Projection mirror 502 Pixel electrode 504 Absorption layer 506 Optical film 508 Alignment layer 510 Liquid crystal layer 512 Alignment layer 514 Electrode layer 516 Substrate 700 Dichroic device 702 Incident light beam 704 Light beam 705 Light beam 706 Reflective display panel 708 Polarization Beam split device (PBS)
710 Polarized beam splitting device (PBS)
712 Reflective display panel 714 (PBS) at the rear stage
716 Interface 718 Image light beam

Claims (20)

In multi-primary digital light splitting and combining system,
An incident light beam is received, and the incident light beam is assumed to have a wavelength value in the first wavelength range larger than the wavelength value in the second wavelength range, and the first light beam in the first wavelength range and the second wavelength range. A dichroic device for splitting into a second light beam;
A first polarization beam splitter (PBS) that receives a first light beam and generates a first polarization beam having a predetermined first polarization state by splitting the first light beam;
A second PBS that receives the second light beam and generates a second polarized beam having a predetermined second polarization state by dividing the second light beam;
A first reflective display panel that receives the first polarized beam and reflects a first image information set corresponding to each of a plurality of primary colors;
A second reflective display panel that receives the second polarized beam and reflects a second set of image information corresponding to each of a plurality of other primary colors; and
A multi-primary digital light comprising: a subsequent PBS that receives the first and second image information sets and combines the first and second image information sets to form an image light beam. Split and join system.   2. The multi-primary digital light splitting and combining system according to claim 1, wherein the first wavelength range is about 650 nm to 700 nm and the second wavelength range is about 400 to 650 nm.   2. The multi-primary digital light splitting and combining system according to claim 1, wherein the first image information set includes three pieces of individual image information of red, yellow and green.   2. The multi-primary digital light splitting and combining system according to claim 1, wherein the second image information set includes three individual image information of magenta, blue and cyan.   2. The multi-primary digital light splitting and combining system according to claim 1, wherein the first image information set includes individual image information of at least two primary colors, and the second image information set includes individual image information of at least two primary colors. And the first wavelength region and the first wavelength region constitute the entire wavelength region of visible light.   The multi-primary digital light splitting and combining system according to claim 1, wherein the incident light beam comprises white light.   2. The multi-primary color digital light splitting and combining system according to claim 1, wherein the first reflective display panel includes a plurality of pixels constituting a pixel array, and each of the pixels includes a plurality of sub-pixels corresponding to the primary colors. System with.   2. The multi-primary color digital light splitting and combining system according to claim 1, wherein the second reflective display panel includes a plurality of pixels constituting a pixel array, and each of the pixels includes a plurality of sub-pixels corresponding to the primary colors. System with. In digital projector,
A light source system for generating a white light beam;
A white light beam is received, and the white light beam is divided into a first light beam and a second light beam, the first light beam having a wavelength range including a first primary color set, and the second light beam is a first light beam. A dichroic device having a wavelength range including two primary color sets;
A first PBS that receives the first light beam and divides and generates a first polarized beam having a predetermined first polarization state from the first light beam;
A second PBS that receives the second light beam and divides and generates a second polarized beam having a predetermined second polarization state from the second light beam;
A first reflective display panel that receives the first polarized beam and reflects a first image information set corresponding to the first primary color set;
A second reflective display panel that receives the second polarized beam and reflects a second image information set corresponding to a second primary color set;
Receiving the first and second image information sets and combining the first and second image information sets to form an image light beam; and receiving the image light beam; A projection lens system for projecting,
A digital projector characterized by comprising:   The digital projector according to claim 9, wherein the first image information set includes three pieces of individual image information of red, yellow, and green.   10. The digital projector according to claim 9, wherein the second image information set includes three individual image information of magenta, blue, and cyan.   10. The digital projector according to claim 9, wherein the first image information set includes individual image information of at least two primary colors, the second image information set includes individual image information of at least two primary colors, and the first wavelength. And the second wavelength range constitute a full wavelength range of visible light.   The digital projector according to claim 9, wherein the incident light beam includes white light.   10. The digital projector according to claim 9, wherein the first reflective display panel includes a plurality of pixels constituting a pixel array, and each of the pixels includes a plurality of sub-pixels corresponding to primary colors.   10. The digital projector according to claim 9, wherein the second reflective display panel includes a plurality of pixels constituting a pixel array, and each of the pixels includes a plurality of sub-pixels corresponding to primary colors. In the multi-primary digital light splitting and combining method,
An incident light beam is received, and the incident light beam is assumed to have a wavelength value in the first wavelength range larger than the wavelength value in the second wavelength range, and the first light beam in the first wavelength range, Placing a dichroic device for splitting into a second light beam;
Receiving the first light beam and splitting a first polarized beam having a predetermined first polarization state from the first light beam;
Receiving the second light beam and splitting a second polarized beam having a predetermined second polarization state from the second light beam;
Receiving a first polarized beam by a first reflective display panel and reflecting a first image information set corresponding to each of a plurality of primary colors;
Receiving a second polarized beam by a second reflective display panel and reflecting a second image information set corresponding to each of a plurality of other primary colors; and the first and second image information sets. A method for splitting and combining multi-primary digital light, comprising: forming an image light beam by combining.   17. The multi-primary color digital light splitting and combining method according to claim 16, wherein the first wavelength range is about 650 nm to 700 nm, and the second wavelength range is about 400 to 650 nm.   17. The multi-primary color digital light splitting and combining method according to claim 16, wherein the first image information set has three pieces of individual image information of red, yellow and green.   17. The multi-primary color digital light splitting and combining method according to claim 16, wherein the second image information set includes three individual image information of magenta, blue and cyan.   17. The multi-primary color digital light splitting and combining method according to claim 16, wherein the first image information set includes individual image information of at least two primary colors, and the second image information set includes individual image information of at least two primary colors. And the first wavelength region and the second wavelength region constitute the entire wavelength region of visible light.

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