WO1997013175A1 - Afficheur a cristaux liquides - Google Patents

Afficheur a cristaux liquides Download PDF

Info

Publication number
WO1997013175A1
WO1997013175A1 PCT/JP1996/002837 JP9602837W WO9713175A1 WO 1997013175 A1 WO1997013175 A1 WO 1997013175A1 JP 9602837 W JP9602837 W JP 9602837W WO 9713175 A1 WO9713175 A1 WO 9713175A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
optical element
holographic optical
liquid crystal
incident
Prior art date
Application number
PCT/JP1996/002837
Other languages
English (en)
Inventor
Yukio Suzuki
Hideki Nakamura
Akira Suzuki
Original Assignee
Casio Computer Co., Ltd.
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
Priority claimed from JP7282668A external-priority patent/JPH09101522A/ja
Priority claimed from JP7352556A external-priority patent/JPH09185048A/ja
Application filed by Casio Computer Co., Ltd. filed Critical Casio Computer Co., Ltd.
Priority to EP96932046A priority Critical patent/EP0795145A1/fr
Priority to KR1019970703746A priority patent/KR100254335B1/ko
Publication of WO1997013175A1 publication Critical patent/WO1997013175A1/fr

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133621—Illuminating devices providing coloured light
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/20—Filters
    • G02B5/203—Filters having holographic or diffractive elements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3102—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators
    • H04N9/3105—Projection 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
    • H04N9/3108—Projection 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 by using a single electronic spatial light modulator

Definitions

  • the present invention relates to a liquid crystal display apparatus, and, more particularly, to a color liquid crystal display apparatus which uses optical means such as holographic optical element.
  • LCD liquid crystal display
  • RGB red
  • G green
  • B blue
  • the color filters in this LCD apparatus absorb lights of complementary color components.
  • the LCD apparatus therefore has a poor efficiency of using light from the back light source and suffers dark color display.
  • an LCD apparatus which improves the light use efficiency by using a holographic optical element.
  • This LCD apparatus has a holographic optical element provided between the light source and the LC cell.
  • This holographic optical element splits parallel light from the back light source to light components of R, G and B wavelengths. The split lights are condensed on the pixels of the LC cell of the associated colors. Accordingly, the lights of the individual wavelengths enter the respective pixels of the LC cell wastelessly.
  • Each of multiple diffraction gratings of the holographic optical element of this LCD apparatus diffracts light of any one of wavelengths of the parallel light incident at a certain angle of incidence (incident angle). Since there are different diffraction angles for different wavelengths of light, light of each wavelength enters the associated pixel of the LC cell. The diffraction angle and diffraction efficiency of this holographic optical element for light of each wavelength are determined by the incident angle of light to the holographic optical element. Therefore, the intensity of light incident to each pixel of the LC cell is not fixed but varies wavelength by wavelength.
  • a generally used holographic optical element has the highest diffraction efficiency for the G wavelength component among the R, G and B wavelength components. It is therefore difficult to acquire a good color characteristic with balanced R, G and B colors.
  • an LCD apparatus which can acquire a good color characteristic with balanced R, G and B colors.
  • an LCD apparatus comprises: a light source (1, 2) for supplying a substantially parallel light flux; an LC device (7) having multiple pixels; -a first holographic optical element (5, 15) for splitting the substantially parallel light flux from the light source (1, 2) into a plurality of light fluxes of different wavelength bands and emitting the split light fluxes in different directions respectively; and a second holographic optical element (6, 16) for guiding the plurality of light fluxes of different wavelength bands emitted from the first holographic optical element (5, 15) to predetermined pixels of the LC device (7) wavelength band by wavelength band.
  • this LCD apparatus can acquire an excellent color characteristic with balanced R, G and B colors.
  • An LCD apparatus comprises: a light source (1, 2) for supplying a substantially parallel light flux; an LC device (7) having multiple pixels; a prism (20, 25) for splitting the substantially parallel light flux from the light source (1, 2) into a plurality of light fluxes of different wavelength bands and emitting the split light fluxes in different directions respectively; and a holographic optical element (21, 26) for guiding the plurality of light fluxes of different wavelength bands emitted from the prism (20, 25) to predetermined pixels of the LC device (7) wavelength band by wavelength band.
  • the holographic optical element can make the intensities of light components incident to the respective pixels of the LC cell substantially the same for any wavelength band.
  • this LCD apparatus can acquire an excellent color characteristic with balanced R, G and B colors.
  • An LCD apparatus comprises: a light source (1, 2) for supplying a substantially parallel light flux; an LC device (7) having multiple pixels; a holographic optical element (51) for splitting the substantially parallel light flux from the light source (1, 2) into a plurality of light fluxes of different wavelength bands and emitting the split light fluxes in different directions respectively; and a lens ( 50) for guiding the plurality of light fluxes of different wavelength bands emitted from the holographic optical element (51) to predetermined pixels of the LC device (7) wavelength band by wavelength band.
  • a plurality of light fluxes of different wavelength bands, split by the holographic optical element, enters the lens at different incident angles. Therefore, the lens can make the intensities of light components incident to the respective pixels of the LC cell substantially the same for any wavelength band.
  • this LCD apparatus can acquire an excellent color characteristic with balanced R, G and B colors.
  • an LCD apparatus comprises: a light source (1, 2) for supplying a substantially parallel light flux; an LC device (7) having multiple pixels; first optical means (5, 15; 20, 25; 51) for splitting the substantially parallel light flux from the light source (1, 2) into a plurality of light fluxes of different wavelength bands and emitting the split light fluxes in different directions respectively; and second optical means (6, 16; 21, 26; 50) for guiding the plurality of light fluxes of different wavelength bands emitted from the first optical means (5, 15; 20, 25; 51) to predetermined pixels of the LC device (7) wavelength band by wavelength band.
  • FIG. 1 is a cross-sectional view illustrating the structure of an LC projector according to the first embodiment of this invention
  • Fig. 2 is a diagram showing a light path for a light of a green (G) wavelength component in the LC projector in Fig. 1;
  • Fig. 3 is a diagram showing a light path for a light of a red (R) wavelength component in the LC projector in Fig. 1;
  • Fig. 4 is a diagram showing a light path for a light of a blue (B) wavelength component in the LC projector in Fig. 1;
  • Fig. 5 is a graph depicting the diffraction efficiency of a second holographic optical element of the LC projector in Fig. 1;
  • Fig. 6 is a diagram showing a first modification of the LC projector according to the first embodiment of this invention.
  • Fig. 7 is a diagram showing a second modification of the LC projector according to the first embodiment of this invention
  • Fig. 8 is a cross-sectional view illustrating the structure of an LC projector according to the second embodiment of this invention
  • Fig. 9 is a diagram showing a first modification of the LC projector according to the second embodiment of this invention.
  • Fig. 10 is a diagram showing a second modification of the LC projector according to the second embodiment of this invention.
  • Fig. 11 is a cross-sectional view illustrating the structure of an LC projector according to the third embodiment of this invention.
  • Fig. 12 is a diagram showing a light path for a light of a green (G) wavelength component in the LC projector in Fig. 11;
  • Fig. 13 is a diagram showing a light path for a light of a red (R) wavelength component in the LC projector in Fig. 11;
  • Fig. 14 is a diagram showing a light path for a light of a blue (B) wavelength component in the LC projector in Fig. 11;
  • Fig. 15 is a cross-sectional view illustrating the structure of an LC projector according to the fourth embodiment of this invention.
  • Fig. 16 is a cross-sectional view illustrating the structure of an LC projector according to the fifth embodiment of this invention.
  • Fig. 17 is a diagram showing a light path from a lamp to pixels of an LC cell of Fig. 16.
  • Fig. 18 is a diagram showing shapes of microlenses associated with unit pixels.
  • Fig. 19 is a diagram showing other shapes of microlenses associated with unit pixels.
  • FIG. 1 illustrates the structure of an LCD projector according to the first embodiment of this invention.
  • a lamp 1 which generates white light is located at the focus point of a reflector 2 having a parabolic surface.
  • the reflector 2 reflects the light from the lamp 1 to be parallel to an optical axis 3.
  • a polarization plate 4 which passes light of a specific polarized light component is provided perpendicular to the optical axis 3 on the light reflecting side of the reflector 2. (This polarization plate 4 will hereinafter be called “incident-side polarization plate.")
  • a first holographic optical element 5 Arranged on the light outgoing side of the incident-side polarization plate 4 is a first holographic optical element 5 inclined to the optical axis 3 by a predetermined angle.
  • a second holographic optical element 6 is provided parallel to the first holographic optical element 5.
  • an LC cell 7 is provided parallel to the second holographic optical element 6.
  • RECTIFIED SHEET (RULE 91) ISA/EP cell 7, a polarization plate 8 (hereinafter called "outgoing-side polarization plate” ) which passes a specific polarized light component is provided parallel to the LC cell 7.
  • a projection lens 9 for projecting an image of light which has passed the outgoing-side polarization plate 8 is located on the light going side of the outgoing-side polarization plate 8.
  • the LC cell 7 has a liquid crystal sealed between a pair of transparent substrates on which electrodes are formed in a dot matrix form and multiple pixels are arranged in a dot matrix form.
  • a black matrix BM for preventing light leakage is provided between the pixels on the substrate to which light is incident.
  • the LC cell 7 has unit pixels each consisting of a set of three color (R, G and B) pixels. One side of each pixel has a size of 54 ⁇ m and the pitch between the pixels is 88 ⁇ m.
  • This LC cell 7 is provided with color filters for R, G and B.
  • the LC cell 7 may however have no color filters.
  • the incident-side polarization plate 4 passes a specific polarized light component (e.g., either linearly polarized S light component or P light component) included in the parallel light which has been emitted from the lamp 1 and has been reflected by the reflector 2.
  • the outgoing- side polarization plate 8 passes a specific polarized light component in the light outgoing from the LC cell 7.
  • the first holographic optical element 5 diffracts light of any wavelength with each diffraction grating.
  • the diffraction angle of the light diffracted by the first holographic optical element 5 varies in accordance with the wavelength.
  • the first holographic optical element 5 is inclined to the optical axis 3 of the lamp 1 by 23 * in order to cause lights of three wavelength components of R, G and B
  • the first holographic optical element 5 diffracts the lights incident at an incident angle of 23' to emit the resultant lights at angles different wavelength by wavelength.
  • the second holographic optical element 6 diffracts light of any wavelength.
  • the diffraction angle of the light diffracted by the second holographic optical element 6 varies in accordance with the wavelength.
  • the second holographic optical element 6 causes the lights from the first holographic optical element 5, which are incident at specific incident angles for the respective wavelength components, to enter the respective pixels of the LC cell 7 corresponding to the individual colors.
  • the second holographic optical element 6 has unit holographic optical elements arranged in association with unit pixels each consisting of a set of three color (R, G and B) pixels of the LC cell 7. Those unit holographic optical elements have the maximum diffraction efficiency for the R wavelength at a point HA shown in Figs.
  • the pitch d A of the diffraction grating at the point HA is set to 1.006 nm
  • the pitch d of the diffraction grating at the point HB is set to 0.848 nm
  • the pitch d c of the diffraction grating at the point HC is set to 0.733 nm.
  • the second holographic optical element 6 has such a characteristic that the diffraction efficiency of light of the G wavelength component is high when lights of individual wavelength components are incident at an incident angle of 40', the diffraction efficiency of light of the R wavelength component is high when lights of individual wavelength components are incident at an incident angle of 43' and the diffraction efficiency of light of the B wavelength component is high when lights of individual wavelength components are incident at an incident angle of 37' .
  • the second holographic optical element 6 is arranged at an interval of approximately 10 ⁇ m with respect to the first holographic optical element 5.
  • the second holographic optical element 6 has an interval of approximately 1100 ⁇ m with respect to the surface of the LC cell 7 to which light is incident. The operation of this LC projector will now be described.
  • the light from the lamp 1 is reflected by the reflector 2 to become parallel to the optical axis 3.
  • This parallel light comes perpendicularly incident to the incident-side polarization plate 4, which selectively passes the light of a specific polarized light component.
  • the light of the specific polarized light component selected by the incident-side polarization plate 4 enters the first holographic optical element 5 at an incident angle of 23 * .
  • the lights of the R, G and B wavelength components incident to the first holographic optical element 5 are diffracted at different diffraction angles by the first holographic optical element 5 and respectively go out thereof at different outgoing angles, as shown in Figs. 2 to 4.
  • the lights which have left the first holographic optical element 5 enter the 10
  • the lights of the individual wavelength components incident to the second holographic optical element 6 are condensed to the associated pixels of the LC cell 7 corresponding to the respective colors.
  • the light of the G wavelength component incident to the first holographic optical element 5 at an incident angle of 23' is diffracted and goes out of the first holographic optical element 5 at an outgoing angle of 40".
  • the light having left the first holographic optical element 5 enters the second holographic optical element 6 at an incident angle of 40'.
  • the light incident to the point HB of the second holographic optical element 6 leaves the second holographic optical element 6 substantially perpendicularly and hits the associated pixel for G of the LC cell 7.
  • the light incident to the point HA of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for G of the LC cell 7.
  • the light incident to the point HC of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for G of the LC cell 7.
  • the light of the R wavelength component incident to the first holographic optical element 5 at an incident angle of 23 * is diffracted and goes out of the first holographic optical element 5 at an outgoing angle of 43'.
  • the light having left the first holographic optical element 5 enters the second holographic optical element 6 at an incident angle of 43' .
  • the light incident to the point HA of the second holographic optical element 6 leaves the second holographic optical element 6 substantially perpendicularly and hits the associated pixel 11
  • the light incident to the point HB of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for R of the LC cell 7.
  • the light incident to the point HC of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for R of the LC cell 7.
  • the light of the B wavelength component incident to the first holographic optical element 5 at an incident angle of 23' is diffracted and goes out of the first holographic optical element 5 at an outgoing angle of 37' .
  • the light having left the first holographic optical element 5 enters the second holographic optical element 6 at an incident angle of 37 * .
  • the light incident to the point HC of the second holographic optical element 6 leaves the second holographic optical element 6 substantially perpendicularly and hits the associated pixel for B of the LC cell 7.
  • the light incident to the point HB of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for B of the LC cell 7.
  • the light incident to the point HA of the second holographic optical element 6 leaves the second holographic optical element 6 at a predetermined outgoing angle and hits the associated pixel for B of the LC cell 7.
  • the parallel light emitted from the lamp 1 and reflected by the reflector 2 is diffracted at different diffraction angles wavelength by wavelength by the first holographic optical element 5. That is, the outgoing lights of the individual wavelength components from the first holographic optical element 5 enter the second holographic optical element 6 at their optimal incident angles. It is therefore possible to improve the diffraction efficiency of light of each wavelength component by the second 12
  • the second holographic optical element 6 can efficiently condense lights of the individual wavelength components onto the associated pixels of the LC cell 7 for corresponding colors.
  • the lights of the individual wavelength components which have passed the LC cell 7 and the outgoing-side polarization plate 8 are projected as an image by the projection lens 9.
  • a clear and bright projected image can be acquired.
  • the wavelengths of the lights emitted from the lamp 1 are not limited to those three.
  • light of a wavelength component lying between the R and G wavelength components goes out the first holographic optical element 5 at an outgoing angle of 40' to 43'.
  • the outgoing light from the first holographic optical element 5 is diffracted by the second holographic optical element 6.
  • the outgoing light from the second holographic optical element 6 enters one of a pixel for R of the LC cell 7, the black matrix BM and a pixel for G of the LC cell 7 in accordance with the wavelength.
  • light of a given wavelength band around the R wavelength component enters a pixel for R of the LC cell 7, and light of a given wavelength band around the G wavelength component enters a pixel for G of the LC cell 7.
  • Yellow light which belongs to neither band, is absorbed by the black matrix BM. Even though the LC cell 7 has no color filters, therefore, the color of light leaving the LC cell 7 does not become unclear.
  • the above-described LC projector has the first and second holographic optical elements 5 and 6 arranged side by side, the arrangement is not limited to this particular type but may take a form as shown in Fig. 6 or Fig. 7. 13
  • a transparent plate 10 of glass or the like is arranged on the light outgoing side of the incident-side polarization plate 4, inclined at a predetermined angle (23") with respect to the optical axis 3.
  • the first holographic optical element 5 is provided on the light-incident surface of this transparent plate 10 and the second holographic optical element 6 is provided on the light-outgoing surface of the transparent plate 10.
  • a transparent plate 10 of glass or the like is arranged on the light outgoing side of the incident-side polarization plate 4, inclined at a predetermined angle (23") with respect to the optical axis 3.
  • the first holographic optical element 5 is provided on the light-outgoing surface of this transparent plate 10 and the second holographic optical element 6 is provided on the light-outgoing surface of the first holographic optical element 5.
  • the LC projectors according to the first and second modifications have quite the same functions and advantages of the LC projector of the first embodiment.
  • Second Embodiment Fig. 8 is a cross-sectional view illustrating the structure of an LCD projector according to the second embodiment of this invention. To avoid the redundant description, like or same reference numerals are given to those components of this embodiment which are the same as the corresponding components of the first embodiment.
  • the incident-side polarization plate 4 is provided perpendicular to the optical axis 3 on the light reflecting side of the reflector 2, which reflects the light from the lamp 1 to be parallel to the optical axis 3.
  • a first holographic optical element 15 is arranged on the light outgoing side of the incident-side polarization plate 4 as an optical element inclined perpendicular to the optical axis 3. Accordingly, a parallel light of a specific polarized 14
  • a second holographic optical element 16 is provided parallel to the first holographic optical element 15.
  • the LC cell 7, the outgoing-side polarization plate 8 and the projection lens 9 are arranged perpendicular to the optical axis 3 in the named order.
  • the first holographic optical element 15 diffracts light of any wavelength with each diffraction grating.
  • the diffraction angle of the light diffracted by the first holographic optical element 15 varies in accordance with the wavelength.
  • the first holographic optical element 15 causes lights of three wavelength components of R, G and B to go out at different angles.
  • the second holographic optical element 16 diffracts light of any wavelength.
  • the diffraction angle of the light diffracted by the second holographic optical element 16 varies in accordance with the wavelength.
  • the second holographic optical element 16 causes the lights incident at their specific incident angles to enter the respective pixels of the LC cell 7 for corresponding colors.
  • second holographic optical element 16 has unit holographic optical elements arranged in association with unit pixels each consisting of a set of three color (R, G and B) pixels of the LC cell 7. Those unit holographic optical elements have diffraction gratings formed in the same way as those of the first embodiment.
  • the pitch d A of the diffraction grating at the point HA is set to 3.141 nm
  • the pitch d B of the diffraction grating at the point HB is set to 2.182 nm
  • the pitch d c of the diffraction grating at the point HC is set to 1.624 nm.
  • the parallel light emitted from the lamp 1 and reflected by the reflector 2 is diffracted at different diffraction angles wavelength by wavelength by the first holographic optical element 15. That is, the outgoing lights of the individual wavelength components from the first holographic optical element 15 enter the second holographic optical element 16 at their optimal incident angles. It is therefore possible to improve the diffraction efficiency of light of each wavelength component by the second holographic optical element 16. That is, the second holographic optical element 16 can efficiently condense lights of the individual wavelength components onto the associated pixels of the LC cell 7 for corresponding colors. As a result, a clear and bright projected image can be acquired.
  • the reflection at the first holographic optical element 15 can be minimized if the incident light is an S polarized light component. As light of a specific polarized light component perpendicularly enters the first holographic optical element 15, there is less elliptically polarized light produced by the reflection at the back of the first holographic optical element 15. It is thus possible to effectively and 16
  • the lamp 1, the reflector 2 and the incident- side polarization plate 4 can be arranged in a linear fashion, so that this LC projector can be made more compact than the LC projector of the first embodiment.
  • the above-described LC projector has the first and second holographic optical elements 15 and 16 arranged side by side, the arrangement is not limited to this particular type but may take a form as shown in Fig. 9 or Fig. 10.
  • the transparent plate 10 of glass or the like is arranged perpendicular to the optical axis 3 on the light outgoing side of the incident-side polarization plate 4.
  • the first holographic optical element 15 is provided on the light- incident surface of this transparent plate 10 and the second holographic optical element 16 is provided on the light-outgoing surface of the first holographic optical element 15.
  • the transparent plate 10 is arranged perpendicular to the optical axis 3 on the light outgoing side of the incident- side polarization plate 4.
  • the first holographic optical element 15 is provided on the light-outgoing surface of this transparent plate 10 and the second holographic optical element 16 is provided on the light-outgoing surface of the first holographic optical element 15.
  • the LC projectors according to the first and second modifications have quite the same functions and advantages of the LC projector of the second embodiment.
  • Third Embodiment Fig. 11 is a cross-sectional view illustrating the structure of an LCD projector according to the third embodiment of this invention. To avoid the redundant description, like or same reference numerals are given to those components of this embodiment which are the same as the corresponding components of the first embodiment.
  • the incident-side polarization plate 4 is provided perpendicular to the optical axis 3 on the light reflecting side of the reflector 2, which reflects the light from the lamp 1 to be parallel to the optical axis 3.
  • a prism 20 as an optical element is arranged on the light outgoing side of the incident-side polarization plate 4.
  • the prism 20 has a light-incident surface inclined to the optical axis 3 and a light-outgoing surface formed perpendicular to the optical axis 3.
  • a holographic optical element 21 is provided perpendicular to the optical axis 3.
  • the LC cell 7, the outgoing-side polarization plate 8 and the projection lens 9 are arranged perpendicular to the optical axis 3 in the named order.
  • the prism 20 diffracts parallel lights of specific polarized light components passed the incident-side polarization plate 4 at different angles according to their wavelengths and causes the diffracted lights to leave.
  • the prism 20 has the light-incident surface inclined to the light-outgoing surface by approximately 38.2', as shown in Figs. 12 through 14. Accordingly, the incident angle of the light to the prism 20 becomes approximately 38.2'.
  • the refractive index of the prism 20 is 1.962.
  • the holographic optical element 21 diffracts light of any wavelength.
  • the diffraction angle of the light diffracted by the holographic optical element 21 varies in accordance with the wavelength.
  • the holographic optical element 21 causes the lights incident at their specific incident angles to enter the respective pixels of the LC cell 7 for corresponding colors.
  • This holographic optical element 21 has unit holographic optical elements arranged in association with unit pixels each consisting of a set of three color (R, G and B) pixels of the LC cell 7. Those unit holographic optical elements have diffraction gratings formed in the same way as those of the first embodiment.
  • the pitch d A of the diffraction grating at the point HA is set to 1.006 nm
  • the pitch d B of the diffraction grating at the point HB is set to 0.848 nm
  • the pitch d c of the diffraction grating at the point HC is set to 0.733 nm.
  • the holographic optical element 21 is arranged at an interval of approximately 10 ⁇ m with respect to the light- outgoing surface of the prism 20 and an interval of approximately 1100 ⁇ m with respect to the light-incident surface of the LC cell 7. The operation of this LC projector will be discussed below.
  • the light from the lamp 1 is reflected by the reflector 2 to become parallel to the optical axis 3.
  • This parallel light perpendicularly enters the incident-side polarization plate 4, which selectively passes the light of a specific polarized light component.
  • the light of the specific polarized light component selected by the incident-side polarization plate 4 enters the prism 20 at an incident angle of 38.2'.
  • the lights of the R, G and B wavelength components incident to the prism 20 are diffracted at 19
  • the lights which have left the prism 20 enter the holographic optical element 21 at the optimal incident angles for the respective wavelength components.
  • the lights of the individual wavelength components incident to the holographic optical element 21 are condensed to the associated pixels of the LC cell 7 for corresponding colors. The above will be discussed specifically for each of the R, G and B wavelength components.
  • the light of the G wavelength component incident to the prism 20 at an incident angle of 38.2' is diffracted and goes out of the prism 20 at an outgoing angle of 40 * .
  • the light having left the prism 20 enters the holographic optical element 21 at an incident angle of 40 * .
  • the light incident to the point HB of the holographic optical element 21 leaves the holographic optical element 21 substantially perpendicularly and hits the associated pixel for G of the LC cell 7.
  • the light incident to the point HA of the holographic optical element 21 leaves the holographic optical element 21 at a predetermined outgoing angle and hits the associated pixel for G of the LC cell 7.
  • the light incident to the point HC of the holographic optical element 21 leaves the holographic optical element 21 at a predetermined outgoing angle and hits the associated pixel for G of the LC cell 7.
  • the light of the R wavelength component incident to the prism 20 at an incident angle of 38.2' is diffracted and goes out of the prism 20 at an outgoing angle of 41.7 * .
  • the light having left the prism 20 enters the holographic optical element 21 at an incident angle of 41.7 * .
  • the light incident to the point HA of the holographic optical element 21 leaves the holographic optical element 21 substantially perpendicularly and hits the associated pixel for R of the LC cell 7.
  • the light of the B wavelength component incident to the prism 20 at an incident angle of 38.2' is diffracted and goes out of the prism 20 at an outgoing angle of 39' .
  • the light having left the prism 20 enters the holographic optical element 21 at an incident angle of 39' .
  • the light incident to the point HC of the holographic optical element 21 leaves the holographic optical element 21 substantially perpendicularly and hits the associated pixel for B of the LC cell 7.
  • the light incident to the point HB of the holographic optical element 21 leaves the holographic optical element 21 at a predetermined outgoing angle and hits the associated pixel for B of the LC cell 7.
  • the light incident to the point HA of the holographic optical element 21 leaves the holographic optical element 21 at a predetermined outgoing angle and hits the associated pixel for B of the LC cell 7.
  • the parallel light emitted from the lamp 1 and reflected by the reflector 2 is diffracted at different diffraction angles wavelength by wavelength by the first holographic optical element 5. That is, the outgoing lights of the individual wavelength components from the prism 20 enter the holographic optical element 21 at their optimal incident angles. It is therefore possible to improve the diffraction efficiency of light of each wavelength component by the holographic optical element 21 so that lights of the individual wavelengths can efficiently be diffracted by the holographic optical element 21 to be efficiently condensed on the associated pixels of the LC 21
  • Fourth Embodiment Fig. 15 is a cross-sectional view illustrating the structure of an LCD projector according to the fourth embodiment of this invention. To avoid the redundant description, like or same reference numerals are given to those components of this embodiment which are the same as the corresponding components of the third embodiment.
  • the incident-side polarization plate 4 is provided perpendicular to the optical axis 3 on the light reflecting side of the reflector 2, which reflects the light from the lamp 1 to be parallel to the optical axis 3.
  • a prism lens is provided perpendicular to the optical axis 3 on the light reflecting side of the reflector 2, which reflects the light from the lamp 1 to be parallel to the optical axis 3.
  • a holographic optical element 25 as an optical element is arranged perpendicular to the optical axis 3 on the light outgoing side of the incident- side polarization plate 4.
  • the LC cell 7, the outgoing-side polarization plate 8 and the projection lens 9 are arranged perpendicular to the optical axis 3 in the named order.
  • the prism lens 25 diffracts parallel lights of specific polarized light components passed the incident- side polarization plate 4 at different angles according to their wavelengths and causes the diffracted lights to leave.
  • the light-incident surface of the prism lens 25 is a sawtooth-shaped lens surface.
  • the light-outgoing surface of the prism lens 25 is a plane perpendicular to the optical axis 3.
  • the prism lens 25 has microprism lenses 25a corresponding to unit pixels each consisting of three color (R, G and B) pixels of the LC cell 7. In this case, each microprism lens 25a has a light-incident lens surface inclined at an angle of 38.2 * with respect to the light- outgoing plane.
  • the refractive index of each microprism lens 25a is 1.926.
  • the holographic optical element 26 is the same as the one in the third embodiment, and condenses the light of the R wavelength component, the light of the G wavelength component and the light of the B wavelength component onto the associated pixels.
  • the parallel light emitted from the lamp 1 and reflected by the reflector 2 is diffracted at different diffraction angles wavelength by wavelength by the prism lens 25. That is, the outgoing lights of the individual wavelength components from the prism lens 25 enter the holographic optical element 26 at their optimal incident angles. It is therefore possible to improve the diffraction efficiency of light of each wavelength component by the holographic optical element 26 and efficiently diffract the lights of the individual wavelengths by means of the holographic optical element 26 to be efficiently condensed onto the associated pixels of the LC cell 7 for corresponding colors. This can provide a clear and bright projected image.
  • the microprism lenses 25a which constitute the prism lens 25 in the fourth embodiment are associated with unit pixels each consisting of three color (R, G and B) pixels of the LC cell 7.
  • the microprism lenses 25a may however be associated with the respective pixels of the LC cell 7.
  • Fifth Embodiment Fig. 16 is a cross-sectional view illustrating the structure of an LCD projector according to the fifth embodiment of this invention. To avoid the redundant description, like or same reference numerals are given to those components of this 23
  • the lamp 1 is located at the focus point of the reflector 2 which has a parabolic surface.
  • the reflector 2 reflects light generated from the lamp 1 to produce light parallel to the optical axis 3.
  • a holographic optical element 51 is arranged on the light reflecting side of the reflector 2 and is inclined at a predetermined angle to the optical axis 3.
  • the incident-side polarization plate 4 which selectively passes a specific polarized light component is arranged parallel to the holographic optical element 51.
  • a flat-shaped condenser lens 50 is arranged parallel to the incident-side polarization plate 4 on the light outgoing side of this polarization plate 4.
  • the LC cell 7 is provided parallel to the condenser lens 50 on the light outgoing side of the condenser lens 50.
  • the outgoing-side polarization plate 8 which selectively passes a specific polarized light component among the lights passed the LC cell 7, is arranged parallel to the LC cell 7.
  • the projection lens 9 for projecting an image of light which has passed the outgoing-side polarization plate 8 is located on the light going side of the outgoing-side polarization plate 8.
  • the LC cell 7 has a liquid crystal sealed between a pair of transparent substrates on which electrodes are formed in a dot matrix form and multiple pixels are arranged in a dot matrix form.
  • a black matrix BM for preventing light leakage is provided between the pixels on the substrate to which light is incident.
  • the LC cell 7 has unit pixels cyclically arranged, each of which consists of a set of three color (R, G, and B) pixels.
  • the individual pixels of R, G and B are arranged in the order of B, G and R along the light splitting direction of the holographic optical element 51 (from left 24
  • This LC cell 7 is provided with color filters for R, G and B.
  • the LC cell 7 may not however be provided with color filters.
  • the holographic optical element 51 diffracts light of any wavelength with each diffraction grating.
  • the diffraction angle of the light diffracted by the holographic optical element 51 varies in accordance with the wavelength.
  • parallel light emitted from the lamp 1 and reflected by the reflector 2 enters the holographic optical element 51 at a predetermined incident angle.
  • the holographic optical element 51 splits the incident light to parallel lights for individual wavelength bands. That is, the diffraction gratings of the holographic optical element 51 are formed at a uniform pitch.
  • the holographic optical element 51 diffracts the light of the G wavelength band toward substantially the direction of the normal line and causes the light to leave accordingly.
  • the holographic optical element 51 diffracts the light of the R wavelength band at a greater diffraction angle than that of the light of the G wavelength band and causes the light to leave accordingly.
  • the holographic optical element 51 diffracts the light of the B wavelength band at a smaller diffraction angle than that pf the light of the G wavelength band and causes the light to leave accordingly.
  • the light splitting direction (resolution direction) of the holographic optical element 51 is set in the left-to-right direction.
  • the condenser lens 50 condenses the parallel lights of individual wavelengths, split by the holographic optical element 51, on the associated pixels of the LC cell 7 for corresponding colors.
  • the condenser lens 50 has microlenses 50a cyclically arranged which are associated with unit pixels each consisting of three color (R, G and B) pixels of the LC cell 7. As shown in Fig. 18, each 25
  • microlens 50a is formed in a hexagonal shape, which has a pixel for G of the LC cell 7 at the center and connects the centers of six adjoining pixels for R and B around the center pixel. As shown in Fig. 17, the microlenses 50a are convex lenses with the convex surfaces facing the holographic optical element 51. The microlenses 50a condenses parallel incident lights of individual wavelength bands onto the associated pixels of the LC cell 7 for corresponding colors in accordance with the wavelengths (incident angles) of the lights.
  • the light of the G wavelength band is condensed on the associated pixel for G of the LC cell 7
  • the light of the R wavelength band is condensed on the associated pixel for R of the LC cell 7
  • the light of the B wavelength band is condensed on the associated pixel for B of the LC cell 7.
  • the holographic optical element 51 As shown in Fig. 16, light from the lamp 1 is reflected by the reflector 2 to be parallel to the optical axis 3. This parallel light enters the holographic optical element 51 at a predetermined incident angle.
  • the parallel light incident to the holographic optical element 51 is diffracted at different diffraction angles for the R, G and B wavelength bands by the holographic optical element 51 and the diffracted lights leave the holographic optical element 51 as parallel lights for the respective wavelength bands, as shown in Fig. 17.
  • the light of the G wavelength band is diffracted substantially in the direction of the normal line of the holographic optical element 51 and leaves the holographic optical element 51 accordingly.
  • the light of the R wavelength band is diffracted at a greater diffraction angle than that of the light of the G wavelength band and leaves the holographic optical element 51 at a predetermined angle in the direction of the normal line of the holographic optical element 51.
  • the light of the B wavelength band is 26
  • the holographic optical element 51 diffracted at a smaller diffraction angle than that of the light of the G wavelength band and leaves the holographic optical element 51 at a predetermined angle in the opposite direction to the outgoing direction of the light of the R wavelength band with respect to the normal line of the holographic optical element 51.
  • the outgoing light from the holographic optical element 51 enters the incident-side polarization plate 4, which selectively passes specific polarized light components.
  • the lights passed the incident-side polarization plate 4 enter the respective microlenses 50a of the condenser lens 50 at incident angles which differ wavelength by wavelength.
  • the lights incident to the microlenses 50a at the different incident angles are condensed on the associated pixels of the LC cell 7 for corresponding colors by the microlenses 50a as shown in Fig. 17.
  • the light of the G wavelength band which has substantially perpendicularly entered the associated microlens 50a is condensed on the associated pixel for G of the LC cell 7.
  • the light of the R wavelength band which has entered the associated microlens 50a at a predetermined angle is condensed on the associated pixel for R of the LC cell 7.
  • the light of the B wavelength band which has entered the associated microlens 50a at a predetermined angle in the opposite direction to the direction of the light of the R wavelength band is condensed on the associated pixel for B of the LC cell 7.
  • Specific polarized light components of the light passed through the LC cell 7 are selectively passed by the outgoing-side polarization plate 8.
  • the lights passed this outgoing-side polarization plate 8 are projected as an image by the projection lens 9.
  • holographic optical element 51 Parallel lights with different incident angles for the respective R, G and B wavelength bands leave the holographic optical element 51. It is therefore possible to split the light from the lamp 1 to light components of individual wavelength bands with fewer parts. This feature simplifies the structure of the LC projector.
  • the microlenses 50a of the condenser lens 50 condense the respective lights, split by the holographic optical element 51, on the associated pixels of the LC cell 7 in accordance with the wavelength bands. This prevents lights of complementary color components from being absorbed by color filters or prevents the light from the lamp 1 from being shielded by the black matrix BM. This LC projector can therefore prevent light loss. It is thus possible to improve the efficiency of using the light from the lamp 1 and acquire a bright color image and a bright projected image.
  • the holographic optical elements 5, 15 and 51 used in the first, second and fifth embodiments diffract light of any wavelength band with each diffraction grating so that light is diffracted at different diffraction angles wavelength by wavelength. That is, although each of the holographic optical elements used in the first, second and fifth embodiments has a single element structure, the structures of those holographic optical elements are not limited to this type. For instance, a three-layer structure in which three types of holographic optical elements capable of selectively passing lights of the respective R, G and B wavelengths may be used.
  • the holographic optical elements in the first, second and fifth embodiments and the prisms in the second and fourth embodiments are used as means for splitting parallel light from the lamp. According to this invention, however, any optical means which splits incident light wavelength by 28
  • wavelength and emits the split light components wavelength by wavelength may be used in placed of the holographic optical elements and prisms.
  • the incident-side polarization plate is arranged on the light incident side of the optical means (the holographic optical elements 5 and 15 and the prisms 20 and 25) in the first to fourth embodiments, whereas the incident-side polarization plate is arranged on the light outgoing side of the optical means in the fifth embodiment.
  • the incident-side polarization plate may however be arranged on either side.
  • the holographic optical elements in the first to fourth embodiments and the microlenses in the fifth embodiment are used as means for condensing lights incident at different angles for the respective wavelength bands onto predetermined and associated pixels. According to this invention, however, any optical means which condenses lights incident at different angles for the respective wavelength bands on predetermined and associated pixels may be used instead of the mentioned holographic optical elements and microlenses.
  • each microlens has a hexagonal shape in the fifth embodiment
  • the structure of the microlens is not limited to this type.
  • each of unit pixels may have three pixels for R, G and B arranged linearly and each microlens 50b may be formed in a rectangular shape in association with this unit pixel.
  • the condenser lens is formed by cyclically arranging those microlenses 50b.
  • the LCD apparatuses according to the first to fifth embodiments are to be considered as some of adaptable forms of this invention.
  • This invention can be adapted to any LCD apparatus which uses combined two optical means. How to combine those two optical means and the characteristics of those two optical means may be selected to provide the desired results through experiments.

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Diffracting Gratings Or Hologram Optical Elements (AREA)
  • Liquid Crystal (AREA)

Abstract

La lumière parallèle émise par une lampe (1) produisant une lumière blanche se réfléchit sur un réflecteur (2) et pénètre dans un premier élément optique holographique (5). Ce premier élément optique holographique (5) émet des composantes de lumière après avoir décomposé la lumière parallèle en plusieurs composantes de lumière de couleur de différentes bandes de longueurs d'ondes. Les composantes de lumière émises par le premier élément optique holographique (5) arrivent sur un second élément optique holographique (6) sous des angles d'incidence différents selon les longueurs d'ondes. Grâce au second élément optique holographique (6), les lumières des différentes bandes de longueurs d'ondes arrivent respectivement en incidence sur les pixels respectifs d'un afficheur à cristaux liquides (7).
PCT/JP1996/002837 1995-10-04 1996-09-30 Afficheur a cristaux liquides WO1997013175A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP96932046A EP0795145A1 (fr) 1995-10-04 1996-09-30 Afficheur a cristaux liquides
KR1019970703746A KR100254335B1 (ko) 1995-10-04 1996-09-30 액정표시장치

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP7282668A JPH09101522A (ja) 1995-10-04 1995-10-04 液晶表示装置
JP7/282668 1995-10-04
JP7/352556 1995-12-29
JP7352556A JPH09185048A (ja) 1995-12-29 1995-12-29 液晶表示装置

Publications (1)

Publication Number Publication Date
WO1997013175A1 true WO1997013175A1 (fr) 1997-04-10

Family

ID=26554703

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP1996/002837 WO1997013175A1 (fr) 1995-10-04 1996-09-30 Afficheur a cristaux liquides

Country Status (4)

Country Link
EP (1) EP0795145A1 (fr)
KR (1) KR100254335B1 (fr)
CN (1) CN1166881A (fr)
WO (1) WO1997013175A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2762099A1 (fr) * 1997-04-15 1998-10-16 Corning Inc Dispositif holographique de formation de faisceaux de lumiere colores, polarises et separes angulairement et projecteur d'images video en faisant application
WO2000057218A1 (fr) * 1999-03-24 2000-09-28 Intel Corporation Systeme de projection
WO2001046722A1 (fr) * 1999-12-23 2001-06-28 Neurok, Llc Systeme et procede de fabrication d'un afficheur reflectif - transmissif universel
EP1315986A1 (fr) * 2000-08-07 2003-06-04 Physical Optics Corporation Systeme d'affichage a cristaux liquides holographique (hlcd) 3-d et son procede de realisation
US7404644B2 (en) 2004-05-12 2008-07-29 Sharp Kabushiki Kaisha Time-sequential colour projection
US7950809B2 (en) 2007-03-27 2011-05-31 Seiko Epson Corporation Hologram element, illumination device, projector, and method of manufacturing hologram element

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100386683C (zh) * 2006-03-29 2008-05-07 宁波思达利光电科技有限公司 用于液晶显示器的光学模块及液晶显示器
CN100410761C (zh) * 2006-06-12 2008-08-13 宁波思达利光电科技有限公司 用于液晶显示器的光学模块及液晶显示器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2152724A (en) * 1984-01-10 1985-08-07 Citizen Watch Co Ltd Multicolor picture display device
JPH05249318A (ja) * 1992-03-03 1993-09-28 Shimadzu Corp カラー液晶表示装置
JPH06222361A (ja) * 1993-01-28 1994-08-12 Dainippon Printing Co Ltd ホログラムを用いた液晶表示装置
JPH0792327A (ja) * 1993-09-21 1995-04-07 Dainippon Printing Co Ltd ホログラムを用いたカラーフィルター
US5506701A (en) * 1993-01-28 1996-04-09 Dai Nippon Printing Co., Ltd. Hologram color filter, liquid crystal display device using the same, and fabrication process of hologram color filter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2152724A (en) * 1984-01-10 1985-08-07 Citizen Watch Co Ltd Multicolor picture display device
JPH05249318A (ja) * 1992-03-03 1993-09-28 Shimadzu Corp カラー液晶表示装置
JPH06222361A (ja) * 1993-01-28 1994-08-12 Dainippon Printing Co Ltd ホログラムを用いた液晶表示装置
US5506701A (en) * 1993-01-28 1996-04-09 Dai Nippon Printing Co., Ltd. Hologram color filter, liquid crystal display device using the same, and fabrication process of hologram color filter
JPH0792327A (ja) * 1993-09-21 1995-04-07 Dainippon Printing Co Ltd ホログラムを用いたカラーフィルター

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 00, ( - 00) *
PATENT ABSTRACTS OF JAPAN vol. 18, no. 7 (P - 1670) *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2762099A1 (fr) * 1997-04-15 1998-10-16 Corning Inc Dispositif holographique de formation de faisceaux de lumiere colores, polarises et separes angulairement et projecteur d'images video en faisant application
WO1998047028A1 (fr) * 1997-04-15 1998-10-22 Corning Incorporated Dispositif holographique pour obtenir des faisceaux lumineux colores, polarises a separation angulaire, et projecteur video l'utilisant
WO2000057218A1 (fr) * 1999-03-24 2000-09-28 Intel Corporation Systeme de projection
US6542134B1 (en) 1999-03-24 2003-04-01 Intel Corporation Projection system
WO2001046722A1 (fr) * 1999-12-23 2001-06-28 Neurok, Llc Systeme et procede de fabrication d'un afficheur reflectif - transmissif universel
US6429913B2 (en) 1999-12-23 2002-08-06 Neurok, Llc System and method for the manufacture of a universal reflective-transmissive display
EP1315986A1 (fr) * 2000-08-07 2003-06-04 Physical Optics Corporation Systeme d'affichage a cristaux liquides holographique (hlcd) 3-d et son procede de realisation
EP1315986A4 (fr) * 2000-08-07 2006-05-17 Physical Optics Corp Systeme d'affichage a cristaux liquides holographique (hlcd) 3-d et son procede de realisation
US7660024B2 (en) 2000-08-07 2010-02-09 Physical Optics Corporation 3-D HLCD system and method of making
US7404644B2 (en) 2004-05-12 2008-07-29 Sharp Kabushiki Kaisha Time-sequential colour projection
US7950809B2 (en) 2007-03-27 2011-05-31 Seiko Epson Corporation Hologram element, illumination device, projector, and method of manufacturing hologram element

Also Published As

Publication number Publication date
EP0795145A1 (fr) 1997-09-17
KR100254335B1 (ko) 2000-05-01
CN1166881A (zh) 1997-12-03

Similar Documents

Publication Publication Date Title
JP3298437B2 (ja) 光学素子、偏光照明装置および投写型表示装置
US6286961B1 (en) Illuminating optical system and projection type display
EP1031870B1 (fr) Systeme d'eclairage et projecteur
JP3747621B2 (ja) カラー投影表示装置
JP3780873B2 (ja) 照明装置
EP0938014A1 (fr) Appareil d'éclairage à lumière polarisée et dispositif d'affichage par projection
JPH11271744A (ja) カラー液晶表示装置
WO2010061699A1 (fr) Système mince de rétroéclairage et dispositif d'affichage à cristaux liquides l'utilisant
KR19990044002A (ko) 편광 변환 소자, 편광 조명 장치 및 이것을 사용한 표시 장치 및 투사형 표시 장치
JPH09288268A (ja) 軸外れのフルカラーホログラフフィルタを有する液晶ディスプレイ
US6359719B1 (en) Optical modulator and projector
US6301026B1 (en) Holographic illumination device
JP3746905B2 (ja) 画像プロジェクタ
EP0795145A1 (fr) Afficheur a cristaux liquides
JP4006965B2 (ja) プロジェクタ
JPH06289387A (ja) 照明光学系及び投写型表示装置
JPH08240868A (ja) 投射型カラー表示装置
JPH05181135A (ja) 偏光照明装置及び該偏光照明装置を用いた投写表示装置
JPH09292821A (ja) ホログラム照明用プリズムシート組立体
JP3298579B2 (ja) 偏光照明装置
US6088076A (en) Liquid crystal display apparatus using holographic optical element
JP3669371B2 (ja) 画像表示装置用の照明装置
JPH09274252A (ja) 集光・分光装置
JP3298580B2 (ja) 投写型表示装置
JP2000305047A (ja) 光学素子、偏光照明装置および投写型表示装置

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 96191170.0

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): CN KR SG US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): DE FR GB

ENP Entry into the national phase

Ref document number: 1997 849651

Country of ref document: US

Date of ref document: 19970530

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1019970703746

Country of ref document: KR

WWE Wipo information: entry into national phase

Ref document number: 1996932046

Country of ref document: EP

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWP Wipo information: published in national office

Ref document number: 1996932046

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1019970703746

Country of ref document: KR

WWG Wipo information: grant in national office

Ref document number: 1019970703746

Country of ref document: KR

WWW Wipo information: withdrawn in national office

Ref document number: 1996932046

Country of ref document: EP