Wherein Liquid Crystal Cells Include Microencapsulated Or Polymer Dispersed Liquid Crystal Patents (Class 349/10)
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Patent number: 6414728Abstract: A transportable image display system having direct and projection viewing modes of operation. The image display system comprises a spatial light modulation structure for spatially modulating the intensity of light produced from a light source, and light diffusing panel of electro-optical construction having a light scattering state in which light being transmitted therethrough is scattered in a diffusive manner, and a light transmission state in which light being transmitted therethrough is transmitted without substantial scattering. In the illustrative embodiments, the spatial light modulation structure can be an electrically-addressable LCD panel, or slide-film structures to be viewed. During the direct viewing mode, light produced from the light source is scattered by the light diffusing panel and spatial intensity modulated by the spatial light modulation structure to form a first image for direct viewing.Type: GrantFiled: February 18, 2000Date of Patent: July 2, 2002Assignee: Reveo, Inc.Inventors: Sadeg M. Faris, Le Li
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Patent number: 6365526Abstract: An optical illumination system wherein an increased amount of light from a light source can reach a light valve, in which a luminous flux of the light source is irradiated upon a first lens array. The luminous flux having passed through the first lens array is introduced to the polarization conversion system provided immediately before a second lens array, and a luminous flux coming out from the polarization conversion system is introduced to the second lens array and then irradiated upon the light valve. The first lens array has an image forming position f which satisfies S<f<L where L is an optical path length of a longer one of optical paths of P polarized light and S polarized light decomposed from the luminous flux from the light source by the polarization conversion system and S is an optical path length of a shorter one of the optical paths.Type: GrantFiled: October 13, 2000Date of Patent: April 2, 2002Assignee: Sony CorporationInventors: Tatsuru Kanamori, Kenji Sugihara, Koji Kita, Makoto Shinoda
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Publication number: 20010035918Abstract: A liquid crystal display device and an electro-optical device include substrates facing each other and each having an electrode, the substrates being spaced apart, spacers disposed between the substrates and defining an electro-optical cell together with the substrates, and a colloidal liquid crystal composite (CLCC) formed in the electro-optical cell. The CLCC includes particle-rich inter-domain regions and micro-domains of a mesogenic liquid crystal, and the particle-rich inter-domain regions include colloidal organic particles being networked in the mesogenic liquid crystal.Type: ApplicationFiled: April 25, 2001Publication date: November 1, 2001Inventors: Hajime Nakamura, Jason Crain
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Patent number: 6243152Abstract: A polymer dispersed liquid crystal projection display is provided that has enhanced contrast. In the projection system using a polymer dispersed liquid crystal display (PDLC), polarized light is used as the light source onto the PDLC. The reflected light maintains its polarization, while the scattered light from the off pixels of the PDLC randomize the polarization. The polarized image is then passed through a polarizing filter which eliminates half of the scattered light, whereas practically all of the polarized image is passed onto the display source. In this way, the contrast between the on and off pixels is effectively doubled.Type: GrantFiled: December 17, 1996Date of Patent: June 5, 2001Assignee: Duke UniversityInventors: Richard M. Knox, Mehdi Zeinali
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Patent number: 6177965Abstract: In a display device, counter electrodes are formed in stripes at a position facing pixel electrodes, with a polymer dispersion liquid crystal held between the counter electrodes and pixel electrodes. When a positive-polarity signal is to be impressed to a pixel electrode, a negative-polarity voltage is fed to the counter electrode. On the other hand, when a negative-polarity signal is to be impressed to a pixel electrode, a positive-polarity voltage is added to the counter electrode. In this manner of impression voltages, a high voltage can be applied to the polymer dispersion liquid crystal layer on the pixel electrodes, so that the liquid crystal layer is turned into the transmitting state even if it is thick. Accordingly, the scattering efficiency is improved and images are displayed with high contrast as the liquid crystal layer can be made thick.Type: GrantFiled: January 27, 1997Date of Patent: January 23, 2001Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Takahara, Hideki Omae
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Patent number: 6151086Abstract: An optical system and projector includes a source of light, an output system having a collection angle for receiving light and passing such received light as an output, and a liquid crystal device including relatively low birefringence liquid crystal material for selectively scattering light through a controlled angle such that a major portion of the scattered light may be collected by said output system, or for transmitting light, the output system including an aperture for transmitting such scattered light and blocking unscattered light. A method of optimizing the angle of scattering of output light in a liquid crystal device which is operable to transmit light or to scatter light to match the entrance pupil of an optical system in order to maximize the amount of collected scattered light, includes selecting the birefringence of the liquid crystal material of about 0.16 or less, and placing the liquid crystal material and medium in physical relation to cause such light scattering or transmission.Type: GrantFiled: September 14, 1999Date of Patent: November 21, 2000Assignee: Lambent LLCInventor: James L. Fergason
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Patent number: 6122021Abstract: A liquid crystal display element comprises a pair of substrates provided with electrodes and a liquid crystal and solidified matrix composite material, disposed between the pair of substrates, which includes a nematic liquid crystal dispersed and held in a solidified matrix, the nematic liquid crystal being such that the refractive index of the liquid crystal is changed depending on states of applying a voltage wherein in a state, the refractive index of the liquid crystal substantially coincides with that of the solidified matrix to thereby pass light, and in the other state, the former does not coincide with the latter to thereby cause the scattering of light, wherein the refractive index anisotropy .DELTA.n of the liquid crystal used is 0.18 or higher, and the dielectric anisotropy .DELTA..epsilon..sub.LC of the liquid crystal used satisfies the relation of 5<.DELTA..epsilon..sub.LC <13.Type: GrantFiled: November 30, 1994Date of Patent: September 19, 2000Assignee: Asahi Glass Company, Ltd.Inventors: Yoshinori Hirai, Satoshi Niiyama, Tomoki Gunjima, Masanori Yuki, Masaya Kunigita, Yukio Yoshikawa, Eiji Shidoji
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Patent number: 6088075Abstract: A liquid crystal display device includes a pair of substrates; a liquid crystal layer interposed between the pair of substrates; and an electrode for applying a voltage to the liquid crystal layer. The liquid crystal layer includes a polymer dispersed liquid crystal material having a polymer phase and a liquid crystal phase, and fulfills the conditions represented by: R.multidot..DELTA.n>0.3 and 8R<d where d represents the thickness of the liquid crystal layer in the unit of micrometers, R represents the characteristic length of the liquid crystal phase in the unit of micrometers, and .DELTA.n represents the birefringence of a liquid crystal material forming the liquid crystal phase, and the liquid crystal phase fulfills the conditions represented by: R.multidot..DELTA.n>0.35 and d<1.Type: GrantFiled: May 5, 1998Date of Patent: July 11, 2000Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Kenji Nakao, Masao Yamamoto, Tsuyoshi Uemura
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Patent number: 6088380Abstract: A high efficiency, narrow spectral linewidth lasing pixel device that implements a low-voltage spatially patterned variable loss element placed inside an optically pumped high-gain laser cavity is disclosed. The output properties of this system make it useful for digital projection displays.Type: GrantFiled: April 30, 1998Date of Patent: July 11, 2000Assignee: Spectra Science CorporationInventor: Nabil M Lawandy
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Patent number: 6049364Abstract: A liquid crystal display panel includes a counter substrate having a counter electrode and a multi-layered dielectric film both formed thereon, and an array substrate formed with pixel electrodes and thin-film transistors serving as switching elements. A layer of polymer dispersed liquid crystal material containing a UV-curable resin component and a liquid crystal component is sandwiched and sealed between the counter and array substrates. A light shielding film is formed over each thin-film transistor. The multi-layered dielectric film is a laminated structure of alternating thin-films of SiO.sub.2 and HfO.sub.2. Since the multi-layered dielectric film is of a nature capable of transmitting UV-rays of light therethrough, the UV-curable resin component positioned underneath the multi-layered dielectric film can be cured during the manufacture.Type: GrantFiled: January 27, 1997Date of Patent: April 11, 2000Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Takahara, Shinya Sannohe
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Patent number: 6028649Abstract: A transportable image display system having direct and projection viewing modes of operation. The image display system comprises a spatial light modulation structure for spatially modulating the intensity of light produced from a light source, and light diffusing panel of electro-optical construction having a light scattering state in which light being transmitted therethrough is scattered in a diffusive manner, and a light transmission state in which light being transmitted therethrough is transmitted without substantial scattering. In the illustrative embodiments, the spatial light modulation structure can be an electrically-addressable LCD panel, or slide-film structures to be viewed. During the direct viewing mode, light produced from the light source is scattered by the light diffusing panel and spatial intensity modulated by the spatial light modulation structure to form a first image for direct viewing.Type: GrantFiled: October 20, 1997Date of Patent: February 22, 2000Assignee: Reveo, Inc.Inventors: Sadeg M. Faris, Le Li
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Patent number: 6005651Abstract: In a display panel, a first substrate is opposed to a second substrate and interposing a liquid crystal/resin composite layer. If the display panel is a transmission type display, a film for absorbing light is formed on a black matrix and between pixel electrodes. If the display panel is a reflection type display, a film for absorbing light is formed between reflection electrodes. Further, a counterelectrode is made from a multi-layer film of dielectric films and a transparent electrically conductive film for preventing reflection. The film for absorbing light includes pigments which can absorb light modulated by the liquid crystal/resin composite layer. By using the display panel, a projection display system of high contrast and high brightness can be constructed.Type: GrantFiled: January 16, 1996Date of Patent: December 21, 1999Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Takahara, Hideki Ohmae, Hideaki Mochizuki
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Patent number: 5993689Abstract: A polymer dispersed liquid crystal (PDLC) display element for use in an electronic apparatus wherein the display element operates in a PDLC mode or reverse PDLC mode providing for reduction of visual display haze, improved display contrast. The particular medium includes a liquid crystal portion and a polymer portion and may include a chiral component. In cases where visual display haze and contract is a particular problem in the utility of the reverse PDLC display element, such as in the case where the display element is combined with a solar battery, a sufficient amount of dichroic dye is added to the liquid crystal portion of the medium, and, further, a compound showing no fluorescence emission with respect to a liquid crystal portion, or a polymer or a chiral polymer precursor portion of the medium, is employed.Type: GrantFiled: February 12, 1997Date of Patent: November 30, 1999Assignee: Seiko Epson CorporationInventors: Hidekazu Kobayashi, Eiji Chino, Masayuki Yazaki, Hidehito Iisaka
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Patent number: 5949503Abstract: Reflective spatial light modulators (RSLMs) and projection apparatus employing such RSLMs are disclosed. The RSLM comprises a reflective surface and a superposed light-modulation layer. The reflective surface is configured to have a reflective diffraction optical element or a microfaceted reflective array. Incident light impinging on the RSLM can pass through the light-modulation layer, reflect from the reflective surface, and return through the light-modulation layer to become modulated signal light capable of forming a viewable image if projected onto a screen or other surface. The reflective diffraction optical element or microfaceted reflective array on the reflective surface is operable to cause the signal light to propagate from the RSLM in a different direction than any ghost light reflected from the RSLM.Type: GrantFiled: June 24, 1996Date of Patent: September 7, 1999Assignee: Nikon CorporationInventors: Motoo Koyama, Hideaki Shimomura
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Patent number: 5946064Abstract: An alignment layer, a method for forming the alignment layer, and a liquid crystal display (LCD) adopting the alignment layer are provided. The alignment layer includes a heat-curable resin layer having microgrooves and an optical alignment polymer layer, coated on the heat-curable resin layer. According to the present invention, the thermal stability of the alignment layer is improved. Accordingly, an LCD adopting the alignment layer has improved display performance.Type: GrantFiled: December 29, 1997Date of Patent: August 31, 1999Assignee: Samsung Display Devices Co., Ltd.Inventor: Eung-sang Lee
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Patent number: 5875006Abstract: In a projection-type display apparatus using light scattering type liquid crystal devices, light from a light source is reflected by a reflecting mirror through a collecting lens; reflected light is converted by a lens into a parallel light beam, which is injected into liquid crystal devices disposed on three sides through a dichroic mirror, the liquid crystal devices coloring an image in red, green and blue; the image is projected on a screen through again the dichroic mirror, the collecting lens and an enlarging lens. Further a photodetector is disposed at a focal point of the collecting lens and a function of adjusting the position of the light source on the basis of a result of this detection is added.Type: GrantFiled: February 27, 1997Date of Patent: February 23, 1999Assignee: Hitachi, Ltd.Inventors: Yoshiharu Nagae, Yuji Mori, Yoshiro Mikami, Hideo Sato, Minoru Hoshino, Kyohei Fukuda
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Patent number: 5875008Abstract: In an optical system phase device such as .lambda./2 plate or a .lambda./4 plate is used to convert S polarization to P polarization and vice versa. In the projection display, a white light emitted from a light source is separated by a color separation optical system, including dichroic mirrors or a dichroic prism, into three primary colors which are modulated by optical modulation elements. Then, the modulated lights are synthesized by a color synthesis optical system and projected by a projection element onto a screen. When appropriate plates are inserted appropriately in the optical system of the projection display, the conversion between S and P polarization occurs and an optical bandwidth becomes narrow, and color purity can be improved. A thick transparent plate is preferably adhered to the optical modulation element. A light absorption film is applied to an ineffective plane of the transparent plate.Type: GrantFiled: February 5, 1997Date of Patent: February 23, 1999Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Takahara, Hideki Ohmae, Yoshito Miyatake, Mitsuhiro Wada
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Patent number: 5844638Abstract: A projection type display apparatus comprising a light source apparatus which is provided with an elliptic mirror 12, a light source 11 disposed at the first focal point, a cone-like material disposed at the second focal point, a condenser lens 13, display elements 15R-15B, a color separating and synthesizing optical system, second condenser lenses 16R-16B and a projection lens 19. The cone-like material is one selected from the group of a convex cone lens, a concave cone lens 2, a convex cone-like reflector and a concave cone-like reflector 20. In the projection type display element, light emitted from the light source is introduced into the cone-like material and is emitted as divergent light through the conical surface of the cone-like material.Type: GrantFiled: January 10, 1997Date of Patent: December 1, 1998Assignee: AG Technology Co., Ltd.Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi, Shigeyuki Serizawa, Yoshiyuki Sonda
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Patent number: 5812227Abstract: The liquid crystal device is constituted by disposing a display layer between a pair of electrode plates. The display layer comprises a porous polymer material having open pores partially filled and a low-molecular weight mesomorphic compound impregnating the porous polymer material. The display layer is free from an unfilled portion of the low-molecular weight mesomorphic compound to be effective for providing a liquid crystal device showing a high transmittance and a good contrast. The display layer also comprises a three dimensional network structure coated with a polymer layer, and a low-molecular weight mesomorphic compound impregnating the three-dimensional network structure. The display layer is free from a fibrous part which is unstable against an applied voltage to be effective for providing a liquid crystal device showing no hysteresis.Type: GrantFiled: April 1, 1993Date of Patent: September 22, 1998Assignee: Canon Kabushiki KaishaInventors: Yomishi Toshida, Kazuo Yoshinaga, Toshikazu Ohnishi, Koichi Sato, Takeo Eguchi, Tsuyoshi Shibata
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Patent number: 5798805Abstract: A projection type display apparatus has a light source optical system, a first filter (1), a first aperture (17), a condenser lens (13), a liquid crystal element (15) having a color filter for each pixel, a second aperture (18), a second filter (2), a projection optical system which form a schlieren optical system wherein first and second filters each composed of a spectral element for controlling each color of R, G and B are provided.Type: GrantFiled: December 20, 1995Date of Patent: August 25, 1998Assignee: AG Technology Co., Ltd.Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi
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Patent number: 5784138Abstract: For use in the display screen of a teleconferencing system, a shutter capable of assuming alternative transparent and scattering states and a method of manufacture therefor. In one embodiment, the shutter includes a film of a polymer-dispersed liquid crystal (PDLC) composition of a polymer and a liquid crystal material wherein the liquid crystal material makes up about 78% by weight of the film. The film is cured at a temperature ranging from about 32.degree. C. to about 38.degree. C., thereby decreasing the time it takes for the film to switch between the transparent and scattering states. The shutter further includes first and second layers of a transparent conductor for containing the film therebetween and driver circuitry, coupled to the film, for causing the film to have a response time equal to or less than 8 ms.Type: GrantFiled: August 22, 1996Date of Patent: July 21, 1998Assignee: Lucent Technologies Inc.Inventors: Richard V. Kollarits, Jane D. LeGrange, Timothy M. Miller
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Patent number: 5754260Abstract: A light source optical system for projection 1, dichroic mirrors 21, 22 disposed to have a predetermined included angle .beta., a reflection type liquid crystal optical element blocks 31-33 each including a closely contacted converging lens and having a reflection surface and a projection optical system 4 are provided, wherein the normal line of a dichroic mirror surface and the optical axis of incident light form an included angle .alpha.; the normal line of the reflection surface and the optical axis of incident light form an included angle .gamma.; light emitted from a light source is color-separated so as to become color lights; the color lights are rendered to be parallel light beams, and are modulated and reflected by means of the reflection type liquid crystal optical elements; the reflected light beams are color-synthesized; and the color-synthesized light is projected through a projection lens.Type: GrantFiled: February 27, 1997Date of Patent: May 19, 1998Assignee: AG Technology Co., Ltd.Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi, Shigeyuki Serizawa, Yoshiyuki Sonda, Masaya Kunigita, Yoshinori Hirai
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Patent number: 5737050Abstract: In a light valve, a liquid crystal layer made of liquid crystal/resin composite is interposed between a transparent substrate with a counterelectrode and a reflection substrate with reflection electrodes. The size of the transparent substrate is designed so that the light modulated by the liquid crystal layer is prevented from again entering into the liquid crystal layer after reflected at an interface of the transparent substrate with air. The transparent substrate may be combined with a transparent plate or flat concave lens with a transparent coupling material. Each pixel has a reflection electrode and liquid crystal molecules above the reflection electrode are aligned according to the signals supplied to thin film transistors. The counterelectrode is formed as a multi-layer film of dielectric films and a transparent electrically conductive film. The dielectric films are made of a material having a refractive index of 1.6-1.8, and the optical thickness of the dielectric films is .lambda.Type: GrantFiled: January 16, 1996Date of Patent: April 7, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Takahara, Hideki Ohmae
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Patent number: 5721597Abstract: A method and apparatus in which the liquid crystal material having cross-over frequency is used for displaying an image, the liquid crystal material is dispersed in the transparent polymer in a phase-separated state, a first voltage signal having a first frequency lower than the cross-over frequency is applied to the liquid crystal material to orient reversibly the liquid crystal material to a first direction to display temporary information, then a second voltage signal having a magnitude higher than the first voltage is selectively applied to orient permanently the liquid crystal material to the first direction to display permanent information and a third voltage signal having a second frequency higher than the cross-over frequency is selectively applied to orient the liquid crystal material perpendicularly to the first direction, to erase the permanent information.Type: GrantFiled: February 20, 1996Date of Patent: February 24, 1998Assignee: Fuji Xerox Co., Ltd.Inventors: Takeo Kakinuma, Kensuke Ito, Minoru Koshimizu
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Patent number: 5694189Abstract: A pixel electrode is disposed with an inclination angle to a base member on a front side (namely, an opposite substrate side) of a liquid crystal display panel. The relation between the reflecting surface of the pixel electrode and the main surface of the base member on the front side of the liquid crystal display panel is defined so that the difference between the reflecting angle of light that is entered as incident light and reflected on the surface of the base member and the leaving angle of light emitted as display light via the liquid crystal display panel exceeds the collection angle of the display apparatus. Thus, undesired light on the main surface of the base member of the display surface is separated from light that is displayed. Consequently, an image free of dazzling and deterioration of contrast ratio due to undesired reflected light can be obtained with a high contrast ratio.Type: GrantFiled: June 7, 1995Date of Patent: December 2, 1997Assignee: Kabushiki Kaisha ToshibaInventors: Hiroki Nakamura, Masato Kemmochi, Yoshitaka Yamada, Yoshihiro Watanabe, Michiya Kobayashi, Nozomu Harada
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Patent number: 5659409Abstract: A projection type display apparatus comprising a light source apparatus which is provided with an elliptic mirror 12, a light source 11 disposed at the first focal point, a cone-like material disposed at the second focal point, a condenser lens 13, display elements 15R-15B, a color separating and synthesizing optical system, second condenser lenses 16R-16B and a projection lens 19. The cone-like material is one selected from the group of a convex cone lens, a concave cone lens 2, a convex cone-like reflector and a concave cone-like reflector 20. In the projection type display element, light emitted from the light source is introduced into the cone-like material and is emitted as divergent light through the conical surface of the cone-like material.Type: GrantFiled: October 7, 1993Date of Patent: August 19, 1997Assignee: AG Technology Co., Ltd.Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi, Shigeyuki Serizawa, Yoshiyuki Sonda
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Patent number: 5648860Abstract: A light source optical system for projection 1, dichroic mirrors 21, 22 disposed to have a predetermined included angle .beta., a reflection type liquid crystal optical element blocks 31-33 each including a closely contacted converging lens and having a reflection surface and a projection optical system 4 are provided, wherein the normal line of a dichroic mirror surface and the optical axis of incident light form an included angle .alpha.; the normal line of the reflection surface and the optical axis of incident light form an included angle .gamma.; light emitted from a light source is color-separated so as to become color lights; the color lights are rendered to be parallel light beams, and are modulated and reflected by means of the reflection type liquid crystal optical elements; the reflected light beams are color-synthesized; and the color-synthesized light is projected through a projection lens.Type: GrantFiled: February 18, 1994Date of Patent: July 15, 1997Assignee: AG Technology Co., Ltd.Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi, Shigeyuki Serizawa, Yoshiyuki Sonda, Masaya Kunigita, Yoshinori Hirai
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Patent number: 5644369Abstract: A switchable lens/diffuser including an optical component constructed to form an optical image in cooperation with light directed thereon and a layer of polymer dispersed liquid crystal material having a clear state and a diffusing state, the layer of material being positioned in conjunction with the optical component so that the optical component forms an optical image when the layer of polymer dispersed liquid crystal material is in the clear state and the layer of polymer dispersed liquid crystal material serves as a diffusing screen to form an image in cooperation with the light directed thereon in the diffusing state.Type: GrantFiled: February 24, 1995Date of Patent: July 1, 1997Assignee: MotorolaInventors: Karen E. Jachimowicz, Michael S. Lebby
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Patent number: 5617226Abstract: A liquid crystal projection device includes a light source, a polymer dispersed liquid crystal panel for forming an optical image as a function of changes in the light scattering condition, a polarizing plate disposed on at lest one of the incident and exit sides of the liquid crystal panel with respect to the direction of travel of the light, and a projection lens for projecting the optical image onto a polarizing screen. The polarizing plate is removably and rotatably supported so that, by rotating the polarizing plate, the direction of the axis of polarization of the polarizing plate can be substantially aligned with the direction of the axis of the polarizing screen. The polarizing screen is utilized when the polarizing plate is mounted, but a non-polarizing screen may be utilized when the polarizing plate is not used, i.e., removed.Type: GrantFiled: December 16, 1994Date of Patent: April 1, 1997Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hideki Ohmae, Hiroshi Takahara
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Patent number: 5610735Abstract: A light valve projection apparatus includes a light source, a light valve used for forming optical images in response to a change in light scattering conditions in the light valve of light irradiated from the light source, a projection lens for projecting the optical images on a screen, and a shield for shielding the optical images formed at or near a pupil of the projection lens. If the brightness of light exiting from the light valve, which is in a light scattering state, in a direction tilted by .theta. degrees from a normal dissection of the light valve is assumed to be half as bright as the light outgoing in the normal direction at .theta..sub.1/2, .theta..sub.1/2 of the light valve is less than 23.degree.. The light valve may be a polymer dispersion liquid crystal display panel. When the polymer dispersion liquid crystal display panel is in a transparent state, light transmitted through the liquid crystal display panel is shielded by the shield, thus showing a black display on a screen.Type: GrantFiled: May 26, 1994Date of Patent: March 11, 1997Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hideki Ohmae, Hiroshi Takahara