GB2354658A - Reflective type of liquid crystal display projection system - Google Patents

Reflective type of liquid crystal display projection system Download PDF

Info

Publication number
GB2354658A
GB2354658A GB9922841A GB9922841A GB2354658A GB 2354658 A GB2354658 A GB 2354658A GB 9922841 A GB9922841 A GB 9922841A GB 9922841 A GB9922841 A GB 9922841A GB 2354658 A GB2354658 A GB 2354658A
Authority
GB
United Kingdom
Prior art keywords
polarized
color light
dichroic
light
reflecting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB9922841A
Other versions
GB9922841D0 (en
Inventor
Shin-Gwo Shiue
Kuo-Liang Lee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ADI Corp
Original Assignee
ADI Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ADI Corp filed Critical ADI Corp
Priority to GB9922841A priority Critical patent/GB2354658A/en
Publication of GB9922841D0 publication Critical patent/GB9922841D0/en
Publication of GB2354658A publication Critical patent/GB2354658A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00Details of colour television systems
    • H04N9/12Picture reproducers
    • H04N9/31Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3102Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators
    • H04N9/3105Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00Details of colour television systems
    • H04N9/12Picture reproducers
    • H04N9/31Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141Constructional details thereof
    • H04N9/315Modulator illumination systems
    • H04N9/3167Modulator illumination systems for polarizing the light beam
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00Details of television systems
    • H04N5/74Projection arrangements for image reproduction, e.g. using eidophor
    • H04N5/7416Projection arrangements for image reproduction, e.g. using eidophor involving the use of a spatial light modulator, e.g. a light valve, controlled by a video signal
    • H04N5/7441Projection arrangements for image reproduction, e.g. using eidophor involving the use of a spatial light modulator, e.g. a light valve, controlled by a video signal the modulator being an array of liquid crystal cells

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Projection Apparatus (AREA)
  • Liquid Crystal (AREA)

Abstract

A reflective type liquid crystal projection system, which includes a light source 100 emitting a visible light, a light collecting unit (LCU) 300 transforming the visible light into a first LCU output (Rs + Fp + Bp) and a second LCU output (Rp + Fs + Bs), a polarization transforming device 400 transforming a phase of the second LCU output into a phase of the first LCU output, a first dichroic device 200A reflecting the Rs component to a first optical output path of the first dichroic device and transmitting the Gp+Bp component, a compensating device 200C compensating the Rs component for optical path difference, a second dichroic device 200B, reflecting the Bp component and transmitting the Gp component, a first reflective type optical modulator 203 reflecting the Rp component to a projection lens 207, a second reflective type optical modulator 204 reflecting the Bs component to the second dichroic device 200B and then the Bs component being reflected to the projection lens 207, a third reflective type optical modulator 205 reflecting the Gs component to the second dichroic device 200B, and then the Gs component being reflected to the projection lens 207. Preferably, the LCU includes a first 301 and a second 302 dichroic mirror and a reflecting mirror 303, the polarisation transformer 400 includes a half wavelength plate 401B and the first and second dichroic devices, polarisation beam splitter prisms including a third 201 and fourth 202 dichroic mirrors. Preferably, the compensating means is a glass block of the same optical dimensions as the second dichroic device.

Description

2354658 REFLECTIVE TYPE OF LIQUID CRYSTAL DISIP,LAY PROJECTION SYSTEM The
present invention relates to a projection system, io especially, to a reflective type of liquid crystal display projection system.
Liquid crystal projection systems find utility in many applications, such as those where a large projection screen must be illuminated by a projector occupying a small volume, and also in a high brightness projection display system.
Where intensity of light emitted by a conventional display screen, such as a cathode ray tube (CRT), is not adequate because of a larger size of system and less brightness use of a liquid crystal display for the projection system may be advantageous Prior arts have disclosed several liquid crystal projection systems. However, some disadvantages cannot be solved I effectively.- Refer to Fig. 1, which depicts a traditional liquid crystal projection system, disclosed by the U.S. Patent,,,5530489. As shown in Fig.1, a light source 10, a prism 24 having four dichroic mirrors 24a to 24d, a first polarizing beam splitters (PBS) 21, a second polarizing beam splitters 23, a half wavelength plate 22 and three liquid crystal light valves (LCLV) 25a to 25c are used to transform the input light S+P into the P-polarized light P1 and P2. The disadvantage of the patent is that the prism 24 is formed of gluing together with four dichroic mirrors 24a to 24d. Hence the fabrication of the prism 24 is difficult and the production cost is difficultly reduced.
Refer to Fig.2, which depicts another traditional liquid crystal projection system, disclosed by U.S. patent 5530489. As shown in Fig.2, a light source 20 emits a visible light. A splitter prism 11 transforms the visible light into the S- polarized light. A projection lens 18 provides a projection axis 19. A first liquid crystal light valve (LCLV) 26 is aligned to the projection axis 19. A second LCLV 28 and a third LCLV 30 are positioned on opposite sides of the projection axis 19, respectively. A polarization analyzer 14 is also aligned to the projection axis 19 and positioned on the optical output path of the splitter prism 11. A first dichroic mirror 40 and a second dichroic mirror 42 are located between above-mentioned LCLV 2 26, 28 and 30 as well as the polarization analyzer 14. The first dichroic mirror 40 is used to reflect the S-polarized blue Third LCLV 30. The second dichroic mirror 42 light Bs to the t is used to reflect the S-polarized green light Gs to the third LCLV 28. Through the LCLV 26 to 30, the light consistedof the P-polarized red light, the P-polarized green light and the P-polarized blue light (R+G+B)p is provided. Although the U.S. Patent 5530489 provides a high degree of efficiency contrast and color separation, the working distance, from LCLVs to the projection lens 18, of visible light is too long.
Thus, the volume of the liquid crystal projection system cannot be reduced.
The reflective type of liquid crystal projection method disclosed herein comprises these steps of follow. Providing a light source to emits a visible light being polarized randomly; transforming the visible light into a first LCU output and a second LCU output through a LCU ( light collecting unit), the first LCU output consisting of a first-dire ction -polarized first-color light, a second -direction -polarized second-color light and a second -direction -polarized third-color light, the second LCU output consisting of a second -directio n-polarized first-color light, a first-direction- polarized second-color light and a first- d irectio n -polarized third-color light; transforming 3 a phase of-the second LCU output into a phase of the first LCU output through a polarization transforming device, such as a half wavelength plate: reflecting the first-direction -polarized first-color light to a first optical output path of the first dichroic device and transmitting the second directionpolarized second- color light as well as the second directionpolarized third-color light by the first dichroic device, such as a dichroic mirror; compensating the first-direction-polarized first-color light for optical path difference through a compensating device, such as a glass block; reflecting the second - direction -polarized third-color light to a first optical path of a second dichroic device and transmitting said second -direction-polarized second-color light by the second dichroic device, such as a second dichroic mirror.
The reflective type liquid crystal projection method disclosed herein further comprises these steps as follow. Reflecting the second -direction -polarized first-color light to a third optical output path of the first dichroic device by a first reflective type optical modulator, such as a liquid crystal light valve( LCLV); reflecting the firstdirection-polarized third-color light to the third optical output path of the first dichroic device through the second dichroic device, the first dichroic device and a second reflective type optical modulator, such as a second LCLV; reflecting the first- direction-polarized secondcolor light to the third optical output path of the first dichroic 4 device through the second dichroic device, the first dichroic. device and a third reflective type optical modulator, such as a IN third LCLV.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same, becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
Fig. 1 depicts a traditional liquid crystal projection system disclosed by the U.S. Patent 5153752.
Fig.2 depicts another traditional liquid crystal projection system disclosed by the U.S. Patent 5530489.
Fig.3(a) depicts the liquid crystal projection system disclosed by the present invention.
Fig.3(b) also depicts the liquid crystal projection system disclosed by the present invention.
The present invention includes a reflective type liquid crystal projection method and a reflective type liquid crystal projection system. First, the reflective type liquid crystal projection method will be described as follows.
A reflective type liquid crystal projection method disclosed herein includes these steps of follows. Visible light being polarized randomly is emitted by a light source. The visible light is transformed into a first LCU output and a second LCU output by a LCU ( light collecting unit). The first LCU output consists of a first-direction-polarized first-color light, a second -direction -polarized second-color light and a second direction-polarized third-color light. The second LCU output consisting of a second -direction - polarized first-color light, a first - direction-p olarized second-color light and a first direction -polarized third-color light. The phase of the second LCU output is transformed into the phase of the first LCU output through a polarization- transforming device, such as a half wavelength plate. The first- direction - polarized first color light is reflected to a first optical output path of the first dichroic device but the secon d-direction -polarized second color light. as well as the second -direction - polarized third-color light are transmitted by the first dichroic device, such as a dichroic mirror. The first -direction -polarized first-color light is compensated for the optical path difference by a compensating device, such as a glass block. The second direction-polarized third-color light is reflected to a first optical path of a second dichroic device but the second- 6 direction - polarized second-color light are transmitted by the second dichroic device, such as a second dichroic mirror.
V The reflective type liquid crystal projection method disclosed herein further comprises these steps as follows.
The se con d -dire ction-p olarized first-color light is reflected to a third optical output path of the first dichroic device by a first reflective type optical modulator, such as a liquid crystal light valve ( LCLV). The first-direction- polarized third-color light is reflected to the third optical output path of the first dichroic device by the second dichroic device, the first dichroic device and a second reflective type optical modulator, such as a second LCLV. The first -direction-po larized second-color light is reflected to the third optical output path of the first dichroic device by the second dichroic device, the first dichroic device and a third reflective type optical modulator, such as a third LCLV.
Referring to Fig.3(a), which depicts an embodiment of the present invention, a light collecting optical unit ( LCOU) 300 includes a first dichroic mirror 301, a second dichroic mirror 302 and a reflective mirror 303. A light source 100 is positioned on an optical input path of the collecting 'optical unit 300 to provide white light. The white light is randomly polarized and comprises visible light. That is to say, the white light comprises red light, green light and blue light,etc. Additionally, the red light includes S-polarized red light and 7 P-polarized red light. Similarly, the green light includes S polarized green light and P-polarized green light and the blue light includes S-polarized blue light and P-polarized blue light.
The first dichroic mirror 301 transmits the P-polarized red light but reflects the other light. The second dichroic mirror 302 reflects the S-polarized green light and S-polarized blue light but transmits the other light.
Still referring to Fig.3(a), the present invention also includes a lens array 400, which is positioned on the optical output path of the collecting optical unit 300. The lens array 400 is composed of a first portion and a second portion. The first portion includes a first lens plate 40 1A, a half wavelength plate 401B and a glass plate 401C. Additionally, the first lens plate 401A is coupled to the glass plate 401C through the half wavelength plate 401B. The second portion includes a second lensplate402A. The first lens plate 401A and the second lens plate 402A are made of fly's eye array, respectively, to provide uniform optical output. The half wavelength plate 401B is used to rotate the phase of the input light 90'.
Still referring to Fig.3(a), the present invention also includes the elements described of follow. A first polarization beam splitter prism ( PBS) 200A, a second polarization beam splitter prism ( PBS) 200B, a glass block 200C, a first liquid crystal light valve( LCLV)203, a second LCLV 204, a third LCLV 205 and a projection lens 207. The first PBS 200A is 8 positioned- on the optical output path of the lens array 400. The first PBS 200A has a third dichroic mirror 201, which reflects the S-polarized light of read light and transmits the P-polarized light of green and blue light. Furthermore, the first PBS 200A has three optical output paths including a first optical output path, a second optical output path and a third optical output path. The first optical output path of the first PBS 200A is between the first PBS 200A and the first LCLV 203, and is aligned to the first LCLV 203. The second optical output path of the first PBS 200A is between the first PBS 200A and the third LCLV 205, and aligned to the third LCLV 205.
The third optical output path of the first PBS 200A is aligned to the projection lens 207 and on the contrary side of the first optical output path.
Still referring to Fig.3(a), the second PBS 200B has a fourth dichroic mirror 202, which reflects green light but transmits the other color light. The second PBS 200B is positioned on a second optical output path of the first PBS 200A and is also between the first PBS 200A and the third LCLV 205. The second PBS 200B has two optical output paths, including a first optical output path of the second PBS 200B and a second optical output path of the second PBS 200.
The first optical output path of the second PBS 200B is aligned to the second LCLV 204 and the second optical output path of the second PBS 200B is aligned to the third LCLV 205.
9 1 Still to Fig.3(a), the glass block 200C is positioned on the first optical output path of the first PBS 200A and is also between the first PBS 200A and the first LCLV 203.
The material and size of the glass block 200C are the same with that of the second PBS 200B in order to provide the light passing through the glass block 200C with the optical distance same with the light passing through the second PBS 200B. Additionally, the LCLV 203, LCLV 204 and LCLV 205 are used to reflect the incident -light and concomitantly rotate the phase of the incident light 901. That is to say, if the P-polarized light impinges upon the LCLV, the S-polarized light will be reflected.
Refer to Fig.3(b), which depicts the reflective type liquid crystal projection system. A light source 100 emits a light beam 110 to the collecting optical unit 300. The light beam 110 impinges upon the first dichroic mirror 301, which transmits the P-polarized red light Rp but reflects the other light. Thus, the P-polarized red light Rp transmits through the first dichroic mirror 301 and the green light, the blue light as well as the S-polarized red light Rs+G+B are reflected to the second dichroic mirror 302. After the P-polarized red light Rp transmitting through the first dichroic mirror 301, the Ppolarized red light Rp impinges upon the reflective mirror 303, thus the P-polarized red light Rp are reflected to the first dichroic mirror 30 1. Afterward the P-polarized red light Rp transmits again the first dichroic mirror 301 and then impinges upon the half wavelength plate 40 1 B of the lens array 400.
Still referring to Fig.3(b), while the green light, the blue light as well as the S-polarized red light Rs+G+B impinging upon the second dichroic mirror 302, which reflects the S polarized green light and the S-polarized blue light Gs+Bs, the S-polarized red light, the P-polarized green light as well as the P-polarized blue light Rs+Gp+Bp transmit through the second dichroic mirror 302 and then impinge upon the lens array 400 consisting of a first portion and second portion. The first portion is further composed of a first fly's eye array 401A, a polarization transforming device, such as a half wavelength plate 401B, and a glass plate 401C. The second portion includes a second fly's eye array 401B. Simultaneously, the S-polarized green light and the S-polarized blue light Gs+Bs, reflected by the second dichroic mirror 302, impinge upon the first dichroic mirror 301. Next, the S-polarized green light and the S-polarized blue light Gs+Bs transmit through the first dichroic mirror 301 and combined with the P-polarized red light Rp to form a Rp+Gs+Bs component. A polarization transforming device, such as the above-mentioned half wavelength plate 401B, is aligned to the Rp+Gs+Bs component. After transmitting through the half wavelength plate 401B, the Rp+Gs+Bs component is transformed into the Rs+Gp+Bp component composed with the S-polarized red light Rs, the P-polarized green light and the P-polarized blue.
11 Still referring to Fig.3(b), the Rs+Gp+Bp component will impinge upon first dichroic device, such as the first PBS 200A having the third dichroic. mirror 201, after transmitting 5 through the half wavelength plate 401B. Since the third dichroic mirror 201 reflects the S-polarized light but transmits the other light, the reflected S-polarized red light Rs will be reflected and then passing through a compensating device, such as the glass block 20OC; and then it impinges upon a first reflective optical modulator, such as the first LCLV 203. Simultaneously, the P-polarized green light and the Ppolarized blue Gp+Bp transmit through the third dichroic mirror 201. The S-polarized red light Rs impinging upon the first LCLV 203 will be transformed into the P- polarized red light Rp and be reflected to the projection lens 207 through the dichroic mirror 20 1.
Still referring to Fig.3(b), the P-polarized green light and the Ppolarized blue Gp+Bp transmitting through the third dichroic: mirror 201 will impinge upon the second dichroic device, such as the second PBS 200B having the fourth dichroic mirror 202 which reflects the blue light but transmits the other light. Hence the P- polarized blue Bp is reflected and then impinges upon a second reflective optical modulator, such as the second LCLV 204. Simultaneously, the Ppolarized green light Gp transmits through the fourth dichroic mirror 202. The P-polarized blue Bp impinging upon the second LCLV 204 will be transformed into the S-polarized blue Bs and be reflected to the fourth dichroic mirror 202. The S-polarized blue Bs reflected to the fourth dichroic mirror 202 will again impinge upon the third dichroic mirror 20 1.
Through the third dichroic mirror 20 1, the S-polarized blue Bs will be reflected to the projection lens 207.
Still referring to Fig.3(b), the P-polarized green light Gp transmitting through the fourth dichroic mirror 202 will impinge upon a third reflective optical modulator, such as the third LCLV 205. Through the third LCLV 205, the P-polarized green light Gp is transformed into the S-polarized green light Gs and then reflected to the third dichroic mirror 20 1. Through the third dichroic mirror 201, the polarized green light Gs is reflected to the projection lens 207.
The above mention is summarized as follow. Through the liquid crystal projection device disclosed herein, the random white light from the light source is transformed into the P- polarized red light Rp, the S-polarized green light Gs and the S- polarized blue light Bs. The P-polarized red light Rp, the S-polarized green light Gs and the S-polarized blue light Bs are combined to form a Rp+Gs+Bs component. Finally, the Rp+Gs+Bs component is emitted by the projection lens 207.
As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are 13 illustrated'of the present invention rather than limiting of the present invention. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure.
14

Claims (21)

CLAIMS LA reflective type liquid crystal projection device, which comprises: a light source for emitting a visible light, said visible light comprising a first-color light, a second-color light and a third-color light; a light collecting unit ( LCU) for transforming said visible light into a first LCU output and a second LCU output, said first LCU output consisting of a first- direction -polarized first-color light, a second -direction-polarized second-color light and a second- direction- polarized third-color light, said second LCU output consisting of a second-direction -polarized first-color light, a first-direction -polarized second-color light and a firs t-dire ction -polarized third-color light; polarization-transforming means for transforming a phase of said second LCU output into a phase of said first LCU output, first dichroic. means for reflecting said first- dire ction polarized first-color light to a first optical output path of said first dichroic device and transmitting said second-direction polarized second-color light and said second-direction polarized third-color light; compensating means for compensating said first- direction -polarized first-color light for optical path difference second dichroic means for reflecting said firstdirection polarized third-color light and said ise cond-direction-polarize d third-color light to said first dichroic device, and transmitting said first- direction -polarized second-color light and said second -direction-polarized second-color light; a first reflective type optical modulator for receiving said first - d irec tio n -polarized first-color light and reflecting said second-direction-polarized first-color light to a third optical output path of said first dichroic device; a second reflective type optical modulator, positioned in a first optical output path of said second dichroic device, said second reflective type optical modulator receiving said second -direction- polarized third-color light and reflecting said first- direction- polarized third-color light to said second dichroic device, and said first -direc tio n -polarized third-color light being reflected to said third optical output path of said first dichroic device by said second dichroic device and said first dichroic device; and a third reflective type optical modulator, positioned in a second optical output path of said second dichroic device, said third reflective type optical modulator receiving said second direction-polarized second-color light and reflecting said first-d irection -polarized second-color light to a said second dichroic device, an said first-direction-polarized third-color 16 light being reflected by said second dichroic device and said first dichroic device.
1
2.The device of claim 1, wherein said LCU further comprises:
first dichroic means for transmitting said seconddirection - polarized first-color light but reflecting said firstdirection -polarized firstcolor light, said second-color light and said third-color light; second dichroic means for transmitting said first- direction -polarized first-color light, said second-directionpolarized second-color light said and said second -direction polarized third-color light but reflecting said first- direction polarized second-color light and said first-direction-polarized third-color light; and reflecting means for reflecting said second-directionpolarized first- color light.
3.The device of claim 1, wherein said polarization- transforming means comprises a half wavelength plate.
4.The device of claim 1, wherein said first dichroic means comprises a first polarization beam splitter prism( PBS) having a third dichroic mirror.
-
5.The device of claim 1, wherein said compensating means 17 comprises -a glass block.
6.The device of claim 5, wherein the material and size of said glass block is the same with that of said second dichroic 5 means.
7.The device of claim 1, wherein said second dichroic means comprises a second polarization beam splitter prism PBS) having a fourth dichroic mirror.
8.The device of claim 1, wherein said first reflective type optical modulator comprises a first LCLV ( liquid crystal light valve).
9.The device of claim 1, wherein said second reflective type optical modulator comprises a second LCLV.
IO.The device of claim 1, wherein said third reflective type optical modulator comprises a third LCLV.
1 LA reflective type liquid crystal projection method, which comprises these steps as follow:
providing a light source, said light source emitting a visible light, said visible light being polarized randomly; transforming said visible light into a first LCU output and a second LCU output through a light collecting unit( LCU), said is first LCU - output consisting of a first-dire ctionpolarized first- color light, a second -direction -polarized second-color light and a second-direction-polarized third-color light, said second LCU output consisting of a second-direction -polarized first-color light, a first- directio n- polarized second-color light and a first-direction -polarized third-color light; transforming a phase of said second LCU output into a phase of said first LCU output through a polarization transforming device; reflecting said first- directio n-polarized first-color light to a first optical output path of said first dichroic device through said first dichroic device; transmitting said secon ddirection -polarized second-color light and said second-directionpolarized third-color light through said first dichroic. device; compensating said first- direction -polarized first-color light for optical path difference through a compensating device; reflecting said second-direction -polarized third-color light to a first optical output path of a second dichroic device through said second dichroic device transmitting said fir st- dire ctio n -polarized second-color light and said second - direction -polarized second-color light through said second dichroic device; reflecting said second -direction-polarized first-color light to a third optical output path of said first dichroic device 19 through a -first reflective type optical modulator; reflecting said first -dire ctio n -polarized third-color light to said third optical output path of said first dichroic device through a second reflective type optical modulator, said second dichroic device and said first dichroic device; and reflecting said first - direction -polarized second-color light to said third optical output path of said first dichroic device through a third reflective type optical modulator, said second dichroic device and said first dichroic device.
12.The method of claim 11, wherein said LCU further comprises:
a first dichroic mirror for transmitting said seconddirection -polarized first-color light but reflecting said first- direction -polarized first-color light, said second-color light and said third-color light; a second dichroic mirror for transmitting said firstdirection -polarized first-color light, said second-directionpolarized second-color light said and said s eco nd -direction- polarized third-color light but reflecting said first-directionpolarized second-color light and said first- direction -polarized third-color light; and a reflecting mirror for reflecting sa id second - directionpolarized first-color light.
13.The method of claim 11, wherein said polarization transforming device comprises a half wavelength plate.
V
14 The method of claim 11, wherein said first dichroic, device comprises a first polarization beam splitter prism PBS) having a third dichroic mirror.
15.The method of claim 11, wherein said compensating device comprises a glass block.
16.The method of claim 15, wherein the material and size of said glass block is the same with that of said second dichroic device.
17.The method of claim 11, wherein said second dichroic device comprises a second polarization beam splitter prism PBS) having a fourth dichroic mirror.
18.The method of claim 11, wherein said first reflective type optical modulator comprises a first LCLV ( liquid crystal light value).
19.The method of claim 11, wherein said second reflective type optical modulator comprises a second LCLV.
20.The method of claim 11, wherein said third reflective type optical modulator comprises a third LCLV.
21
2 l.A reflective type liquid crystal projection method, which comprises these steps as follow providing a light source, said light source emitting a visible light, said visible light being polarized randomly; transforming said visible light into a first LCU output and a second LCU output, said first LCU output consisting of a first -direction - polarized first-color light, a second-direction polarized second-color light and a second -direction -polarized third-color light, said second LCU output consisting of a second -direction -polarized first-color light, a first-direction polarized second-color light and a first- direc tion-polarized third-color light; transforming a phase of said second LCU output into a phase of said first LCU output component; reflecting said first- direction - polarized first-color light to a first optical output path of a first dichroic device through said first dichroic device; transmitting said second -direction -polarized second-color light and said second -direction-polarized third-color light through said first dichroic device; compensating said first-direction -polarized first- color light for optical path difference; reflecting said second-direction- polarized third-color light to a first optical output path of a second dichroic device through said second dichroic device; 22 transmitting said firstdirection - polarized second-color light and said second -direction polarized second-color light through said second dichroic device; reflecting said second- direction - p o larized first- color light to a third optical output path of said first dichroic device reflecting said first- direction - po I arized third-color light to said third optical output path of said first dichroic device, said second dichroic device and said first dichroic device; and reflecting said first- direction - p o larize d second-color light to said third optical output path of said first dichroic device, said second dichroic device and said first dichroic device.
23
GB9922841A 1999-09-27 1999-09-27 Reflective type of liquid crystal display projection system Withdrawn GB2354658A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9922841A GB2354658A (en) 1999-09-27 1999-09-27 Reflective type of liquid crystal display projection system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB9922841A GB2354658A (en) 1999-09-27 1999-09-27 Reflective type of liquid crystal display projection system

Publications (2)

Publication Number Publication Date
GB9922841D0 GB9922841D0 (en) 1999-11-24
GB2354658A true GB2354658A (en) 2001-03-28

Family

ID=10861685

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9922841A Withdrawn GB2354658A (en) 1999-09-27 1999-09-27 Reflective type of liquid crystal display projection system

Country Status (1)

Country Link
GB (1) GB2354658A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002080577A1 (en) * 2001-03-30 2002-10-10 Carl Zeiss Jena Gmbh Arrangement for the projection of a multi-coloured image onto a projection surface
DE102004010913A1 (en) * 2004-03-05 2005-09-29 Carl Zeiss Jena Gmbh Projection device comprises light source unit emitting light with first, second and third colors, e.g. red, green and blue
CN100370308C (en) * 2004-06-30 2008-02-20 北京万方同辉科技有限公司 Color splitting mirror stack
CN100370307C (en) * 2004-06-30 2008-02-20 北京万方同辉科技有限公司 Light tuning method and device base on colour splitting mirror stack

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996005534A1 (en) * 1994-08-09 1996-02-22 Philips Electronics N.V. Illumination system for supplying a polarized radiation beam, and image projection device comprising such an illumination system
US5530489A (en) * 1993-03-31 1996-06-25 Henderson; Alan R. Single projection lens color projection system
WO1997045768A1 (en) * 1996-05-29 1997-12-04 Seiko Epson Corporation Projection display

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5530489A (en) * 1993-03-31 1996-06-25 Henderson; Alan R. Single projection lens color projection system
WO1996005534A1 (en) * 1994-08-09 1996-02-22 Philips Electronics N.V. Illumination system for supplying a polarized radiation beam, and image projection device comprising such an illumination system
WO1997045768A1 (en) * 1996-05-29 1997-12-04 Seiko Epson Corporation Projection display

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002080577A1 (en) * 2001-03-30 2002-10-10 Carl Zeiss Jena Gmbh Arrangement for the projection of a multi-coloured image onto a projection surface
US6860605B2 (en) 2001-03-30 2005-03-01 Carl Zeiss Jena Gmbh Arrangement for the projection of a multi- coloured image into a projection surface
DE102004010913A1 (en) * 2004-03-05 2005-09-29 Carl Zeiss Jena Gmbh Projection device comprises light source unit emitting light with first, second and third colors, e.g. red, green and blue
CN100370308C (en) * 2004-06-30 2008-02-20 北京万方同辉科技有限公司 Color splitting mirror stack
CN100370307C (en) * 2004-06-30 2008-02-20 北京万方同辉科技有限公司 Light tuning method and device base on colour splitting mirror stack

Also Published As

Publication number Publication date
GB9922841D0 (en) 1999-11-24

Similar Documents

Publication Publication Date Title
US5829854A (en) Angled color dispersement and recombination prism
US4687301A (en) Full-color projector system with a tricolor-separating prism
EP0389240B1 (en) Polarizing beam splitter apparatus and light valve image projection system
EP0238543B1 (en) Prism assembly for a single light valve full-color projector
WO1988009102A1 (en) Improved optical system for full color liquid crystal light valve image projection
JPH11271744A (en) Color liquid crystal display device
US5812223A (en) Color LCD projector with three color separating polarizing beam splitters
WO2004114003A1 (en) Method and apparatus for recycling reflected light in optical systems as e.g. projection display
US6646690B1 (en) Arrangement of λ/2 retardation plate in projector
US6229648B1 (en) Compact projector
EP1241519A1 (en) Projection display
US6637891B2 (en) Optical system of liquid crystal projector
US7359122B2 (en) Prism assembly
JP3951897B2 (en) Polarization conversion unit and projector using the same
GB2354658A (en) Reflective type of liquid crystal display projection system
JPH03187696A (en) Projection type liquid crystal display device
JP2003255271A (en) Color separating and synthesizing optical system and projection liquid crystal display device using the same
KR100429213B1 (en) optics system of projector
JP4172532B2 (en) Projection type liquid crystal display device
JP2002122810A (en) Optical engine and video display device using the same
JP3019825B2 (en) Projection type color liquid crystal display
TW200417810A (en) 3-panel transmissive projection system
JPH02150886A (en) Liquid crystal projector device, polarizer used for same, and polarizing microscope using polarizer
JPH04318534A (en) Polarized light source device and projection type liquid crystal display device using the same
JP3367501B2 (en) Optical element manufacturing method

Legal Events

Date Code Title Description
WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)