Abstract: Provided is an electro-optical device which allows high-speed response and has high luminance and contrast.

Abstract: An imaging system and method are presented. The system comprises an imaging lens unit, an imaging detector, and a birefringent element located between the imaging lens unit and the imaging detector. The system is thus configure and operable to provide in-focus imaging of objects located at both near-field and far-field ranges. Also provided is an optical device configured to be mounted on an imaging lens, being one of the following: a lens of an individual's glasses, on a contact lens, and an eye internal lens. The optical device is configured to be located between the imaging lens and the retina and comprises a birefringent element, to thereby provide in-focus imaging onto the retina of the objects located at both near-field and far-field ranges therefrom.

Abstract: An electrically tunable Lyot type filter is a Lyot that include one or more filter elements. Each filter element may have a planar, solid crystal comprised of a material that exhibits birefringence and is electro-optically active. Transparent electrodes may be coated on each face of the crystal. An input linear light polarizer may be located on one side of the crystal and oriented at 45 degrees to the optical axis of the birefringent crystal. An output linear light polarizer may be located on the other side of the crystal and oriented at ?45 degrees with respect to the optical axis of the birefringent crystal. When an electric voltage is applied between the electrodes, the retardation of the crystal changes and so does the spectral transmission of the optical filter.

Abstract: An optical device has an electrically insulating first barrier layer disposed over a first electrode layer, a photoconductive layer disposed over the first barrier layer, and a carrier confining layer disposed over the photoconducting layer. The carrier confining layer defines a volume throughout which a plurality of carrier traps are dispersed. Further, an electrically insulating second barrier layer is disposed over the carrier confining layer, a light blocking layer is disposed over the second barrier layer for blocking light of a selected wavelength band. A reflective layer is disposed over the light blocking layer for reflecting light within the selected wavelength band, a birefringent or dispersive layer is disposed over the reflective layer, and an optically transmissive second electrode layer is disposed over the birefringent or dispersive layer. A method is also disclosed, as are additional layers intervening between those detailed above.

Abstract: A birefringent, electrically-controlled, wavelength selective, pixelated optical phase shifting device, in which the correct drive voltage for a desired phase shift through any pixel can be determined independently of changes in the drive voltage arising from changes in the environmental conditions, generally temperature. This is achieved by mounting a monitor phase shifting element controlled by its own drive voltage, in close proximity to the pixelated phase shifter, such that the monitor element and the phase shifter experience the same environmental condition. A probe optical beam of predefined wavelength is directed through the monitor element, and the transmitted beam measured as a function of the monitor drive voltage. This functional relationship is used to define the environmental condition in which the monitor element and the phase shifter, are situated, and the correct drive voltage for application to any phase shifter pixel can be determined.

Abstract: An optical diplexer having a birefringent crystal for providing substantially a whole number of wavelength retardation to first optical energy having said first polarization type, and having a first wavelength, fed to a first end of said crystal, and exiting a second end of said crystal with said first polarization type and said first wavelength and for providing substantially an odd integer number of half wavelength retardation to second optical energy having said first polarization type, having a second wavelength, fed to said second end of said crystal and exiting said first end of said crystal with said second polarization type and said second wavelength. The system includes an electronically actuated polarization aligner for adjusting phase retardation of the second energy fed to the second end of the crystal prior to such second energy entering the second end of the birefringent crystal.

Abstract: On one pair of opposed side faces (1a, 1b) of electro-optic crystal (1), grooves (3a, 3b) are formed so as to make bottom faces of the grooves approach each other and make a distance between the bottom faces shorter than a predetermined distance, and the pair of electrodes (5a, 5b) are formed in the grooves (3a, 3b) so as to fill the grooves nearly completely.

Abstract: An optical apparatus is disclosed. The optical apparatus includes: a first optical element having a first polarizing layer containing a material having a refractive index that changes in accordance with the magnitude of applied voltage and first and second transparent electrodes sandwiching both sides of the first polarizing layer in the direction of thickness and polarizing light passing through the first polarizing layer in the direction of thickness; and a second optical element having a second polarizing layer containing a material having a refractive index that changes in accordance with the magnitude of applied voltage and third and fourth transparent electrodes sandwiching both sides of the second polarizing layer in the direction of thickness and polarizing light passing through the second polarizing layer in the direction of thickness.

Abstract: An image display apparatus includes a backlight unit where a reflection panel is installed at a bottom thereof, a polarization panel which transmits only light of a particular polarization direction of light emitted from the backlight unit, a polarization switch which changes the polarization direction of incident light, a birefringent element array which is formed by alternately arranging a plurality of first and second birefringent elements and changes the polarization direction of incident light to make the polarization directions of light passing through the first and second birefringent elements perpendicular to each other, a reflective polarizer panel which transmits only light of a particular polarization direction of the light passing through the birefringent element array and reflects light of the other polarization direction, a lens array which separates incident light into a first view zone and a second view zone, and a display panel which displays an image.

Abstract: A display apparatus is constituted by display cells, arranged in a row direction and a column direction, each comprising a color filter and an optical modulation device for modulating a brightness and a color of an incident light by voltage application. The optical modulation device modulates color of the incident light over at least three colors and the color filter is provided in a set of color filters including a color filter which transmits light of two colors in the above-mentioned at least three colors. Two types of display modes consisting of a large pixel display mode using a group of display cells containing color filters of all of the above-mentioned at least three colors as a display unit and a small pixel display mode using groups of display cells each containing color filters of a part of the above-mentioned set of color filters as display units are executed.

Abstract: An apparatus and method to operate on a light beam by using a lens that collimates the light beam to a collimated beam with at least one cross-sectional dimension less than a critical dimension of 400 ?m or less over a working range WR. The apparatus has a bulk electro-optic material of small thickness ?, e.g., less than 300 ?m positioned within working range WR and the collimated beam traverses it along its path. The apparatus has a voltage source for applying a low operating or drive voltage Vdrive, e.g. less than 400 V to the bulk electro-optic material for performing an operation on the collimated beam. The lens for collimating the light beam is a free-space collimator such as a graded index (GRIN) lens or preferably a C-lens. The apparatus is a versatile and scalable platform that can be employed in building various electro-optic devices.

Abstract: An optical attenuator with increased dynamic range and reduced temperature-dependence over the dynamic range. The optical attenuator has a Faraday rotational angle variable device which applies an external magnetic field to light polarized by a garnet crystal, and a polarizer and an analyzer disposed at the front and rear of the optical axis of the device. There is an angle x formed between the plane of polarization of the light incident to the garnet crystal and the magnetic field orthogonal to the optical axis, where an angle y is formed between the polarizer and the analyzer, and the angle x is set to satisfy {(?z/2)+90×n}?12<x<{(?z/2)+90×n}+12 (n=0, 1, 2 or 3), where z=y±90; z is the angle of rotation of the plane of polarization caused by the Faraday rotational angle variable device.

Abstract: An optical wavelength filter uses birefringence and polarization to discriminate and block a wavelength stop band. Birefringent elements, each having a fixed retarder and a liquid crystal, are placed along the signal path with the fast and slow axes in each pair being aligned and rotationally displaced from other pairs. The birefringence parts are arranged by their thickness, birefringence and progressive rotational orientation so that each pair contributes to achieving a specific polarization state for specific periodic wavelength discrimination bands. A selection polarizer at the output blocks bands that have this polarization state. The birefringence elements are tuned in a coordinated manner and thereby to select one or more wavelengths as the band stop discrimination band.

Abstract: An ellipsometer includes an optical component and a detector. The optical component has two birefringent parts in optical communication via a border surface. Light incident on the border surface is split into two reflected and two transmitted components. The detector is configured to measure a property of at least three out of the four components. Based on the measured properties, a state of polarization of the incident light may be determined.

Abstract: A variable attenuation signal acquisition probing system and voltage measurement system uses an optical cavity to acquire a signal under test. The probing system has an optical transmitter and receiver that are coupled to the optical cavity via an optical transmission system. The optical cavity has an electrode structure having apertures formed in the optical cavity that are parallel to propagation path of the optical signal within the cavity. A modulated optical signal is generated by the optical cavity in response to the signal under test creating an electromagnetic field distribution in electro-optic material in the optical cavity that overlaps the optical path of the optical signal propagating in the optical cavity which varies the index of refraction of electro-optic material in the optical path. Changes in the polarization state of the optical signal attenuates the magnitude of the output electrical signal of the optical receiver.

Abstract: A dynamic equalizing optical channel router includes an input port for receiving a wavelength division multiplexed composite optical signal comprising a plurality of channels; at least one output port; a diffraction grating optically coupled to the input and output ports; a lens optically coupled to the diffraction grating at a side opposite to the input and output ports; an array of steering devices optically coupled to the lens at a side opposite to the diffraction grating, wherein each channel is reflected by a different steering device of the array; and a plurality of attenuators, wherein each channel reflected by the array traverses one of the attenuators and the diffraction grating to the at least one output port. The router is able to dynamically adjust optical intensity of each wavelength channel by a different amount while also performing the function of wavelength routing.

Abstract: A structure includes a substrate and a light modulating film formed on top of the substrate. The light modulating film is made of polycrystalline PLZT containing Pb, Zr, Ti, and La as constituent elements. The film has a La concentration in the range of 5 at % to 30 at %. The relative dielectric constant at a frequency of 1 MHz is higher than or equal to 1200.

Abstract: The present invention provides a novel indole carboxylic ester trimer which is characterized by being represented by the following general formula (1): wherein R represents a straight or branched chain alkyl group having 1-6 carbon atoms; n is an integer of 1-4; Xa? represents at least one anion selected from a group of anions having a valency of 1-3 consisting of chloride ion, bromide ion, iodide ion, fluoride ion, nitrate ion, sulfate ion, hydrogen sulfate ion, phosphate ion, borofluoride ion, perchlorate ion, thiocyanate ion, acetic acid ion, propionic acid ion, methanesulfonic acid ion, p-toluenesulfonic acid ion, trifluoroacetic acid ion and trifluoromethanesulfonic acid ion; a represents the ionic valence number of X and is an integer of 1-3; and m is 0-0.5.

Abstract: This specification discloses a polarizing. element for dividing light into first and second polarized lights differing in polarized state from each other by a polarizing dividing surface, directing the first polarized light in a first direction, reflecting the second polarized light by a reflecting surface and directing it in the first direction, and varying the polarized state of at least one of the first and second polarized lights to thereby make the polarized states of the first and second polarized lights coincident with each other, characterized in that the polarizing dividing surface is disposed on one surface of a plane parallel plate and the reflecting surface is disposed on the other surface of the plane parallel plate, and the light enters obliquely from the one surface or the other surface. The specification also discloses a polarizing conversion unit provided with such polarizing element, and a projector provided with such polarizing conversion unit.

Abstract: Systems and techniques for changing a polarization profile of light to a desired polarization profile. In some implementations, a polarization modulator is in communication with a stress modulator. The polarization modulator alters the polarization profile of light in response to applied stress from the stress modulator.

Abstract: The attenuation profile of an optical system, which defines the power variation as a function of wavelength is adjusted to alter the slope of its contour. The device is useful in a wavelength division modulation system to flatten the profile of an amplifier or the like that has a non uniform power variation with wavelength. The invention adjusts the slope by first providing an input light signal that has a known polarization state, e.g., processing the input into a known phase and amplitude relation between orthogonal components, such as plane polarized at a given alignment. The signal is then passed through a series of waveplates. The waveplates have different phase retardation and orientation resulting in wavelength dependent polarization change. According to an inventive aspect, by tuning the phase retardation of multiple tunable waveplates the desired wavelength dependent polarization changes over a useful wavelength range can be produced.

Abstract: In a variable optical delay circuit to be used for compensation for polarization mode dispersion of an optical signal and for other purposes, there are provided a first birefringent member, a second birefringent member and a variable optical rotator interposed between the first birefringent member and the second birefringent member for varying a polarization state of light outputted from the first birefringent member. The birefringent members and the variable optical rotator are disposed on the same optical axis, and the optical axis of each of the birefringent members is set to perpendicularly intersect a traveling direction of inputted light. Therefore, by varying the optical rotation angle of the variable optical rotator, an arbitrary delay quantity corresponding thereto is obtainable in a continuous (analog-like) fashion without undergoing spatial separation between polarization components of the inputted light and varying the intensity (loss) of each of the polarization components.

Abstract: A controller, particularly for setting a desired or randomized polarization state of an output light beam derived from an input, has more than the minimum number of controllable optical elements needed to determine the state of the output. The controller applies control input values to obtain a desired output state. The controller also selects among plural alternative sets of control values that could obtain the desired output state, so as to minimize other error conditions. The concurrent error conditions can be associated finite control range limits, for example to keep the input values near a middle of their ranges. Additional error conditions can include minimizing the incremental change in the values from one set to the next. The control is particularly useful to avoid problems associated with using finite range control elements such as liquid crystals for differential retardation or orthogonal light components, when controlling an endless or periodic parameter such as polarization.

Abstract: A lithographic apparatus includes a projection system, which includes a plurality of cubic crystalline optical elements that each impart retardance to a beam of radiation. The optical elements are aligned along an optical axis of the projection system and include two adjacent crystalline optical elements having a common crystalline lattice direction oriented along the optical axis. A first of the two adjacent elements is rotated about the optical axis with respect to a second of the adjacent elements with a predetermined rotation angle. The crystalline optical elements are selected and positioned along the optical axis and the rotation angle is selected such that, for each of two substantially perpendicular polarization states of the beam of radiation having a radiation wavelength of about 193 nm, the patterned beam of radiation has less than about 0.012 waves RMS of wavefront aberration across an exit pupil of the projection system.

Abstract: An electro-optic crystal based beam-steering device preferably based on KTN, having a first deflector and a second deflector. The first deflector has a pair of substrates each having a plurality of first electrode lines extending along a first direction and a plurality of electro-optic crystal modulators interposed between the first electrode lines. The second deflector has a pair of substrates each having a plurality of second electrode lines extending along a second direction and a plurality of electro-optic crystal modulators interposed between the second electrode lines. The first direction is orthogonal to the second direction.

Abstract: A projection optical system includes a first optical element that orients an axis [1 1 1] as a crystal orientation in a cubic system crystal parallel to an optical axis, and a second optical element that orients an axis [1 0 0] as the crystal orientation in the cubic system crystal so that a minimum angle may be 30° or larger between the optical axis and an off-axis edge beam that passes through the second optical element, and a minimum angle may be 10° or smaller between the optical axis and an off-axis principal ray that passes through the second optical element.

Abstract: The present invention provides a transparent optical film that has excellent optical characteristics for realizing the uniform retardation distribution and restraining rainbow-colored irregularities. The optical film, which is obtained by laminating a birefringent layer (a) on a transparent film (b), satisfies all the following formulae (I), (II) and (III). ?n(a)>?n(b)×10??(I) 1<(nx?nz)/(nx?ny)??(II) 0.0005??n(a)?0.5??(III) In the above formulae (I), (II) and (III), ?n(a) and ?n(b) denote respectively birefringent indexes of the birefringent layer (a) and the transparent film (b). The signs of nx, ny and nz indicate refractive indexes in an X-axis direction, a Y-axis direction and a Z-axis direction in the birefringent layer (a), respectively.

Abstract: A variable optical attenuator including: a birefringent element positioned to separate an input optical signal into two spatially separated, orthogonally polarized beams; a LC modulator positioned to receive the orthogonally polarized beams and selectively alter their polarizations; a reflective element positioned to reflect the beams back through the LC modulator and the birefringent element, wherein the birefringent element recombines orthogonally polarized components of the reflected beams to produce an output optical signal; and a controller coupled to the LC modulator to selectively cause the LC modulator to alter the polarizations of the orthogonally polarized beams, wherein during operation the controller is responsive to a request to variably attenuate the intensity of the output optical signal relative to the intensity of the input optical signal to one of multiple non-zero attenuation settings.

Abstract: An exemplary polarization controller includes a first optical element having a first optical axis and configured to receive light having a first phase, a second optical element having a second optical axis and configured to emit the light having a second phase, and a third element having a third optical axis. At least a portion of the third element is interstitial to the first element and the second element. The exemplary controller also includes at least two drivers, both of which can operate in accordance with an exemplary method of present invention.

Abstract: An optical imaging system including an illumination system, a Cartesian PBS, and a prism assembly. The illumination system provides a beam of light, the illumination system having an f/# less than or equal to 2.5. The Cartesian polarizing beam-splitter has a first tilt axis, oriented to receive the beam of light. A first polarized beam of light having one polarization direction is folded by the Cartesian polarizing beam splitter and a second polarized beam of light having a second polarization direction is transmitted by the Cartesian polarizing beam splitter. The Cartesian polarizing beam splitter nominally polarizes the beam of light with respect to the Cartesian beam-splitter to yield the first polarized beam in the first polarization direction. The color separation and recombination prism is optically aligned to receive the first polarized beam. The prism has a second tilt axis, a plurality of color separating surfaces, and a plurality of exit surfaces.

Abstract: A photolithography tool including an optical system for transmitting a beam of radiation toward a substrate is presented. The optical system includes a plurality of calcium fluoride lens elements, optically transmissive of the beam of radiation, each having respective optical axes and imparting a retardance to the beam. The plurality of calcium fluoride lens elements are aligned along an optical path for propagation of the beam of radiation therethrough. Each of the calcium fluoride lens elements includes a cubic crystalline calcium fluoride that is aligned with its [111] lattice direction, or a lattice direction optically equivalent to the [111] lattice direction, substantially parallel with its optical axis. A first calcium fluoride lens element of the plurality of calcium fluoride lens elements is rotated about its optical axis with respect to a second calcium fluoride lens element. The optical system has less than or about 0.015 waves RMS of wavefront aberration.

Abstract: An optical system includes multiple cubic crystalline optical elements aligned along a common optical axis and having their crystal lattices oriented with respect to each other to minimize the effects of intrinsic birefringence and produce a system with reduced retardance. The optical system may be a refractive or catadioptric system having a high numerical aperture and using light with a wavelength at or below 248 nanometers. The net retardance of the system is less than the sum of the retardance contributions of the respective optical elements as the elements are oriented such that the intrinsic birefringences of the individual elements cancel each other out. In one embodiment, two [110] cubic crystalline optical elements are clocked with respect to one another and used in conjunction with a [100] cubic crystalline optical element to reduce retardance. Various birefringent elements, wave plates, and combinations thereof provide additional correction for residual retardance and wavefront aberrations.

Abstract: A compensated higher order waveplate is constructed of substrates. In one embodiment, a first substrate is a n? waveplate and the second substrate is a (n+?)? waveplate. The substrates are oriented so that their principle axes of retardation are orthogonal. n? is a base retardation of a waveplate and ?? is an incremental retardation. The incremental retardation produces a desired amount of retardation of a lightwave passing through the compensated higher order waveplate. Retarder material used to produce the base retardation is approximately ½ a desired thickness of the waveplate. Multiple waveplates are combined to produce any of wavelength band specific retarders and multiple non contiguous wavelength band specific retarders.

Abstract: An optical system includes multiple cubic crystalline optical elements aligned along a common optical axis and having their crystal lattices oriented with respect to each other to minimize the effects of intrinsic birefringence and produce a system with reduced retardance. The optical system may be a refractive or catadioptric system having a high numerical aperture and using light with a wavelength at or below 248 nanometers. The net retardance of the system is less than the sum of the retardance contributions of the respective optical elements as the elements are oriented such that the intrinsic birefringences of the individual elements cancel each other out. In one embodiment, two [110] cubic crystalline optical elements are clocked with respect to one another and used in conjunction with a [100] cubic crystalline optical element to reduce retardance. Various birefringent elements, wave plates, and combinations thereof provide additional correction for residual retardance and wavefront aberrations.

Abstract: Systems for optical wavefront sensing and control based on a phase contrast Fourier domain filtering technique. Optically or electronically controlled phase spatial light modulators (SLM) are used as the Fourier domain filter. A direct adaptive-optic feedback system using the optical wavefront sensing systems. A differential Zernike filter is also disclosed.

Abstract: To provide a compact projector in which a projection image is formed by using four kinds of color light so as to expand an expressible color gamut of the projection image and to achieve an excellent light utilization efficiency, a projector includes a light source, a color-separation optical system, a light-modulation optical system, and a color-synthesis optical system. The color-separation optical system produces four kinds of color light whose output directions are different from each other. The light-modulation optical system includes a first two-color-modulation electro-optical device to modulate any two of the four kinds of color light separated by the color-separation optical system and a second two-color-modulation electro-optical device to modulate the remaining two kinds of color light. Each two two-color-modulation electro-optical device includes a microlens array on a substrate close to the color-separation optical system and a plurality of sub-pixels corresponding to respective microlenses.

Abstract: A polarization mode dispersion generator for generating polarization mode dispersion (“PMD”) spectra is provided. The generator includes a plurality of birefringent stages, each stage including a differential group delay (“DGD”) element and a phase-shifting element. The generator is capable of inducing an amount of polarization mode-mixing between at least one adjacent pair of stages. The shape of a PMD spectrum can be preserved while frequency shifting the spectrum in either direction. Alternatively, the shape of the PMD spectrum can be changed without frequency shifting.

Abstract: An optical system includes multiple cubic crystalline optical elements aligned along a common optical axis and having their crystal lattices oriented with respect to each other to minimize the effects of intrinsic birefringence and produce a system with reduced retardance. The optical system may be a refractive or catadioptric system having a high numerical aperture and using light with a wavelength at or below 248 nanometers. The net retardance of the system is less than the sum of the retardance contributions of the respective optical elements as the elements are oriented such that the intrinsic birefringences of the individual elements cancel each other out. In one embodiment, two [110] cubic crystalline optical elements are clocked with respect to one another and used in conjunction with a [100] cubic crystalline optical element to reduce retardance. Various birefringent elements, wave plates, and combinations thereof provide additional correction for residual retardance and wavefront aberrations.

Abstract: A polarized light color filter for producing R, G and B primary lights from inputted white light in time division. The filter is small in size and strong against mechanical vibration. The projections of the R, G and B lights can be arbitrarily varied in one period. The varying speed is high, and the ratio of utilization of the quantity of light from the light source is high. Elements 36(1), 38(1), 40(1), 38(2), 40(2), 38(3), 40(3), 38(4) and 36(2) are in order stacked and bonded between glass substrates (30, 32). The elements 38(1) to 38(4) are polarized light converting elements for selecting either a mode in which the inputted light is outputted as it is by applied voltage control or a mode in which the inputted light is converted from one polarized light to the other and outputted. The elements 40(1) to 40(3) are narrow-band polarization spectroscopic elements reflecting only the S-polarized components of the R, G and B lights and transmitting the other components.

Abstract: A diagnostic system (24) for a PEM (20) provides optically determined information about the retardance characteristics induced by the PEM (20). The diagnostic system (24) is integrated with the PEM (20) so that the PEM (20) performance may be diagnosed or monitored during operation of the PEM (20). Specifically, the diagnostic system (24) is used alongside an optical setup (22) that employs a primary light beam (28) for conventional purposes such as polarimetry, optical metrology, etc. The diagnostic system (24) includes its own diagnostic light source (50) that is directed through the optical element (32) of the PEM (20) at a location remote from the primary aperture (38) of the PEM (20). Thus, the diagnostic system (24) and the primary PEM (20) operation can be undertaken simultaneously, with one not interfering with the other. The output of the diagnostic system reflects the actual retardance characteristic provided by the PEM (20) and can be used as feedback to adjust the PEM control as needed.

Abstract: Optical devices using reflective polarizers and, in particular, diffusely reflective polarizers are provided. Many of the optical devices utilize the diffusely reflecting and specularly transmitting properties of diffusely reflecting polarizers to enhance their optical characteristics. The optical devices include a lighting system which uses a reflector formed from a diffusely reflecting polarizer attached to a specular reflector. Another optical device is a display apparatus which uses a diffusely reflecting polarizer layer in combination with a turning lens which folds shallow angle light toward a light modulating layer. Other optical devices exploit the depolarizing characteristics of a diffusely reflecting polarizer when reflecting light. Still other optical devices use diffusely reflecting polarizers to recycle light and improve display illumination.

Abstract: A variable optical attenuator including: a birefringent element positioned to separate an input optical signal into two spatially separated, orthogonally polarized beams; a LC modulator positioned to receive the orthogonally polarized beams and selectively alter their polarizations; a reflective element positioned to reflect the beams back through the LC modulator and the birefringent element, wherein the birefringent element recombines orthogonally polarized components of the reflected beams to produce an output optical signal; and a controller coupled to the LC modulator to selectively cause the LC modulator to alter the polarizations of the orthogonally polarized beams, wherein during operation the controller is responsive to a request to variably attenuate the intensity of the output optical signal relative to the intensity of the input optical signal to one of multiple non-zero attenuation settings.

Abstract: The present invention provides a technique of readily manufacturing a projector. The projector comprises: an illumination optical system for emitting light; an electro-optical device for modulating the light emitted from the illumination optical system in response to image information; a projection optical system for projecting a modulated light generated by the electro-optical device; and an optical component having a rock crystal member composed of rock crystal, the optical component being located in an optical path including the illumination optical system and the projection optical system. For example, the optical component provided on a light incident side or a light exiting side of the electro-optical device has a rock crystal substrate 308G as the rock crystal member and a polarizing plate 302Go arranged on the substrate. It is preferable that a Z axis of the rock crystal substrate 308G is set to be substantially parallel to or substantially perpendicular to the surface of the substrate.

Abstract: A projection type display apparatus including an illumination optical system for emitting a light flux, a decomposition optical system for decomposing the light flux into color lights of red, green and blue, liquid crystal light valves for the colors for receiving the decomposed color lights, a synthesis optical system for synthesizing the image lights of the colors from the liquid crystal light valves, and a projection optical system for projecting the synthesized image lights to a screen. A filter is disposed at one of positions opposing to each other across the center of the light flux between the white light source and the decomposition optical system and attenuates or cuts off light of a wavelength region different from that of light which passes the other of the positions.

Abstract: A compensated higher order waveplate is constructed of substrates. In one embodiment, a first substrate is a n&lgr; waveplate and the second substrate is a (n+&Dgr;)&lgr; waveplate. The substrates are oriented so that their principle axes of retardation are orthogonal. n&lgr; is a base retardation of a waveplate and &Dgr;&lgr; is an incremental retardation. The incremental retardation produces a desired amount of retardation of a lightwave passing through the compensated higher order waveplate. Retarder material used to produce the base retardation is approximately ½ a desired thickness of the waveplate. Multiple waveplates are combined to produce any of wavelength band specific retarders and multiple non contiguous wavelength band specific retarders.

Abstract: A variable optical attenuator including: a birefringent element positioned to separate an input optical signal into two spatially separated, orthogonally polarized beams; a LC modulator positioned to receive the orthogonally polarized beams and selectively alter their polarizations; a reflective element positioned to reflect the beams back through the LC modulator and the birefringent element, wherein the birefringent element recombines orthogonally polarized components of the reflected beams to produce an output optical signal; and a controller coupled to the LC modulator to selectively cause the LC modulator to alter the polarizations of the orthogonally polarized beams, wherein during operation the controller is responsive to a request to variably attenuate the intensity of the output optical signal relative to the intensity of the input optical signal to one of multiple non-zero attenuation settings.

Abstract: A semiconductor optical device includes a substrate, an optical waveguide layer on the substrate and having well and barrier layers. The semiconductor optical device also includes an optical absorbing layer on the substrate and adjacent to the optical waveguide layer so that incident light having an incident wavelength &lgr;LD is guided into the optical absorbing layer. Each of the well layers has a wavelength &lgr;g corresponding to the band gap of the well layers and that is larger than the incident wavelength &lgr;LD. Also, the band gap energy between base levels of a conduction band and a valence band of the optical waveguide layer is larger than the energy of the incident light having the incident wavelength &lgr;LD.

Abstract: The present invention is directed to an optical space switch accommodating a plurality of input light paths and output light paths. The optical space switch comprises a plurality of polarization control optical switches, each consisting essentially of: polarization control means having elements, one for each input light path, for rotating through 90° the polarizing direction of light information incident from each input light path or otherwise retaining the polarizing direction thereof for output; and a light path routing element for routing the light path for the light information output from the polarization control means in accordance with the polarizing direction of the light information. These polarization control optical switches are arranged in a matrix pattern or coupled in cascade to implement a polarization control optical space switch.

Abstract: Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the “ladder”experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments.

Abstract: Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the “ladder” experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments.