Abstract: In one embodiment, a video display system employs an array of ribbon light modulators having a reflective surface configured to reflect or diffract a beam. The beam may have a wavelength suitable for displaying a video image. The reflective surface may comprise an aluminum alloy suitable for receiving the beam, which may have a relatively high power density. In one embodiment, a method of displaying a video image comprises impinging a beam on a portion of a reflective surface of a light modulator. The beam may have a wavelength suitable for displaying a video image, and the reflective surface may comprise an aluminum alloy.

Abstract: An exposure apparatus (8) for fabricating optical film (40) by exposing a pattern such as for photoalignment, where the optical film (40) has a photosensitive layer (20) and a substrate (10). The exposure apparatus (8) directs an exposure beam from a light source (1) to a reflective polarization modulation device (88). The modulated exposure beam is then directed onto the photosensitive layer (20) for forming a pattern onto the optical film (40). A reflective surface (50) is disposed to reflect, back through the optical film (40), a portion of the exposure beam transmitted through the optical film (40), in order to obtain a photoreactive response. The source of exposure radiation and the reflective surface (50) are on opposite sides of the optical film (40).

Abstract: A switching array comprising a plurality of total internal reflection (TIR) switches can be used to direct optical signals from any one of a plurality of input optical fibers to any one of a plurality of output optical fibers. Free space regions exist between the input optical fibers, the switches, and the output optical fibers. Accordingly, the light from an input optical fiber to an output optical fiber travels through the TIR switch array largely, if not entirely, in free space mode. To provide efficient coupling of light from the input optical fibers to the plurality of switches and ultimately to the output optical fibers, collimators and other coupling elements are employed. Preferably, the collimators have a Rayleigh range longer than the path length that the light will travel from the respective input optical fiber to the respective output optical fiber.

Abstract: A method of fabricating optical filter is disclosed. The method includes providing the substrate and selectively etching the substrate to form a plurality of freestanding layers. A plurality of dielectric layers is disposed over an outer surface of each of the freestanding layers. The resultant optical filters may be used in a variety of applications including etalon applications.

Abstract: Opto-electronic oscillators having a frequency locking mechanism to stabilize the oscillation frequency of the oscillators to an atomic frequency reference. Whispering gallery mode optical resonators may be used in such oscillators to form compact atomic clocks.

Abstract: A display device 100 has a display unit 110 and a display switching unit 120. The display switching unit 120 is provided with a reflective polarizing plate 121, a liquid crystal panel 122, and a polarizing plate 123 arranged in this order from the side of the display unit 110 to the observation side. By controlling the liquid crystal panel 122, the display switching unit can be switched between a light transmissive state and a light reflective state. The display unit 110 and the display switching unit 120 are optically adhered to each other by an adhesive layer 131. Thus, deterioration of the contrast by boundary reflection can be restrained, and the flatness and the rigidity of the device can be improved.

Abstract: An exposure system (8) for fabricating optical film (40) by exposing a pattern such as for photoalignment, where the optical film (40) has a photosensitive layer (20) and a substrate (10). The exposure system (8) directs an exposure beam from a light source (1) to a reflective polarization modulation device (88). The modulated exposure beam is then reflected onto the photosensitive medium (20) for forming a pattern onto the optical film (40).

Abstract: An integrated device including one or more device drivers and a diffractive light modulator monolithically coupled to the one or more driver circuits. The one or more driver circuits are configured to process received control signals and to transmit the processed control signals to the diffractive light modulator. A method of fabricating the integrated device preferably comprises fabricating a front-end portion for each of a plurality of transistors, isolating the front-end portions of the plurality of transistors, fabricating a front-end portion of a diffractive light modulator, isolating the front end portion of the diffractive light modulator, fabricating interconnects for the plurality of transistors, applying an open array mask and wet etch to access the diffractive light modulator, and fabricating a back-end portion of the diffractive light modulator, thereby monolithically coupling the diffractive light modulator and the plurality of transistors.

Abstract: The invention provides a method for fabricating an optical device comprising at least one optical component formed on a transparent substrate. The method comprises determining an area of the substrate that is to be light-absorbing; and fabricating a light-absorbing mask on the determined area prior to fabricating the at least one optical component. The invention also provides an optical device comprising a substrate; and first and second optical components formed on the substrate, wherein the first optical component has two modes, each mode producing a different optical response to light incident thereupon, and wherein the second optical component absorbs light and is formed on the substrate before the first optical component is formed.

Abstract: An optical gate according to the invention comprises a polarization divider to divide an optical signal into two orthogonal polarization components and to output them as a first polarization component which precedes in the time base and a second polarization component which follows the first one in the time base; a semiconductor optical amplifier to modulate the phase of the second polarization component output from the polarization divider according to a control light; an assist light supplier to supply to the semiconductor optical amplifier an assist light to help the recovery of the refractive index variation of the semiconductor optical amplifier caused by the control light; a polarization combiner to combine the first and second polarization components of the optical signal transmitting on the semiconductor optical amplifier so as to adjust them in the same time location; and a polarization extractor to extract a predetermined polarization direction component from the output from the polarization combine

Abstract: An electro-modulating device for modulating light from a light source, as part of an opto-electronic communication network has a modulating medium for modulating light passing therethrough by varying an electric field applied across the modulating medium, an optical input-output surface, a light reflector, and electrodes for applying the varying electric field across the modulating medium. The input-output surface, the medium and the reflector are arranged so that light enters the medium through the input-output surface, travels through the medium towards the reflector, is reflected by the reflector to travel back through the medium towards the input-output surface, and exits the medium through the input-output surface. The electric field is transverse to light traversing the medium between the input-out surface and the reflector, to make it easier to couple an optic fiber to the input-output surface of the modulating medium.

Abstract: A separable modulator architecture is disclosed. The modulator has a mirror suspended from a flexible layer over a cavity. The flexible layer also forms supports and support posts for the mirror. An alternative separable modulator architecture has a mirror suspended over a cavity. The modulator is supported by supports and support posts. The support posts comprise a flexible layer over support post plugs. A bus structure may be formed upon the flexible layer arranged over the support posts.

Abstract: An exposure system (8) for fabricating optical film (40) by exposing a pattern such as for photoalignment, where the optical film (40) has a photosensitive layer (20) and a substrate (10). The exposure system (8) directs an exposure beam from a light source (1) to a reflective polarization modulation device (88). The modulated exposure beam is then reflected onto the photosensitive medium (20) for forming a pattern onto the optical film (40).

Abstract: This invention relates to a semiconductor device and method for switching or modulating optical signals. The semiconductor device has a photodetector having a low electrical capacitance Cd, a detector absorbing layer for absorbing an optical signal beam, a modulator having a low capacitance Cm and a modulator absorbing layer exhibiting an electric field-dependent absorption coefficient. The modulator absorbing layer is used for absorbing an optical power beam, which is to be modulated or switched. The device has a low resistivity region between the photodetector and the modulator such that the electric field-dependent absorption coefficient is altered uniformly and rapidly throughout the modulator absorbing layer during absorption of the optical signal beam in the detector absorbing layer. The device is equipped with a high resistivity element in series with the low resistivity region for minimizing a net charge flow to and from the device.

Abstract: An optical device including a substrate, a distributed feedback (DFB) semiconductor laser formed on the substrate and including a diffraction grating having an asymmetrical &lgr;/4 phase shift region, the diffraction grating extending along an optical axis of the DFB semiconductor laser, and a field absorbing modulator integrated with the DFB semiconductor laser on the substrate for modulating a light wave emitted from the DFB semiconductor laser, the optical modulator having a facet reflection rate between 0.01 and 0.02% at an output end thereof, the diffraction grating having a &kgr;L value between 1 and 1.2. The proper combinations of the &kgr;L value of the diffraction grating and the reflection rate of the output facet of the modulator of the DFB semiconductor laser can fabricate the source for integrating the modulator having the excellent quality with a higher yield and lower cost.

Abstract: A multi-gas sensor is provided which modulates a polarized light beam over a broadband of wavelengths between two alternating orthogonal polarization components. The two orthogonal polarization components of the polarization modulated beam are directed along two distinct optical paths. At least one optical path contains one or more spectral discrimination means, with each spectral discrimination means having spectral absorption features of one or more gases of interest being measured. The two optical paths then intersect, and one orthogonal component of the intersected components is transmitted and the other orthogonal component is reflected. The combined polarization modulated beam is partitioned into one or more smaller spectral regions of interest where one or more gases of interest has an absorption band.

Abstract: An adaptive pulse compressor is described, especially for use with ultrashort pulses, wherein the input pulses are modified in an iterative fashion, according to a feedback signal obtained from measurement of the output pulses. The feedback signal is programmed, by means of a programmable spatial light modulator, to allow for independent control of the individual spectral components of the incoming pulses, such that almost arbitrary phase functions can be realized to accomplish efficient compression. One of the main disadvantages associated with prior art pulse compressors, namely, the need for characterization of the uncompressed pulses, is thus eliminated. The compressor is thus capable of handling completely uncharacterized or partially characterized input pulses, or pulses from time varying sources.

Abstract: A light modulator is comprised of two unit devices each using surface plasmon generated at the interface between thin metal films respectively formed on prisms and an electro-optical material, and a mirror. Both of the transmitted light due to absorption and re-radiation, and the reflected light arising from the unit devices are made into the outgoing light, the incident light on the next unit device, or the incident light on the mirror. Consequently, all light beams can be utilized as the final outgoing light beams with no loss of light. Further, the color of light can be spatially divided, and still further, it can also be temporally divided by changing the wavelength due to a voltage. As a result, the original light can be divided both temporally and spatially with almost no loss by combining two unit devices so configured as to re-radiate the absorbed light by surface plasmon using surface plasmon and a mirror, and thus utilizing both of the reflected light and the transmitted light.

Abstract: A light modulator is comprised of two unit devices each using surface plasmon generated at the interface between thin metal films respectively formed on prisms and an electro-optical material, and a mirror. Both of the transmitted light due to absorption and re-radiation, and the reflected light arising from the unit devices are made into the outgoing light, the incident light on the next unit device, or the incident light on the mirror. Consequently, all light beams can be utilized as the final outgoing light beams with no loss of light. Further, the color of light can be spatially divided, and still further, it can also be temporally divided by changing the wavelength due to a voltage. As a result, the original light can be divided both temporally and spatially with almost no loss by combining two unit devices so configured as to re-radiate the absorbed light by surface plasmon using surface plasmon and a mirror, and thus utilizing both of the reflected light and the transmitted light.

Abstract: A light modulating switch (210) including a switching element (218) having a first portion (226) of electro-optic material to which first and second electrodes (213, 224) are associated. A second portion (228) is composed of material having an index of refraction matching that of the first portion (226) when no voltage is applied to electro-optically activate the first portion (226), but the index of refraction of the second portion (228) is less than the index of refraction of the first portion (226) when the first portion (226) is electro-optically activated by application of voltage to the electrodes (213, 224).

Abstract: A light-emitting system comprises a rare earth-containing organic light-emitting device (10, 11, 12, 13) fabricated on a silicon-based substrate (1). The light-emitting device is associated with a resonant cavity which may be in the form of a ridge or buried ridge waveguide (6). A diode (27) may form a modulator region (26) for injection of free carriers into the waveguide. This changes the refractive index or local absorption of the resonant cavity and thus allows switching of the system. The system is preferably a laser operating at about 1.5 &mgr;m although other wavelengths may be used. The wavelength is selected by the rare earth used.

Abstract: A device which simultaneously maximizes light reflectivity from one side of the device while maximizing light transmissivity from the opposite side of the device. The device is configured with distinct regions of transparency and reflectivity including a plurality of reflective structures. The structures are generally smaller towards a light transmitting side of the device and larger towards a light reflective side of the device.

Abstract: One aspect of the invention provides a method for fabricating a microelectromechanical systems device. The method comprises fabricating an array of first elements, each first element conforming to a first geometry; fabricating at least one array of second elements, each second element conforming to a second geometry; wherein fabricating the arrays comprises selecting a defining aspect of each of the first and second geometries based on a defining characteristic of each of the first and second elements; and normalizing differences in an actuation voltage required to actuate each of the first and second elements, wherein the differences are as a result of the selected defining aspect, the defining characteristic of each of the elements being unchanged.

Abstract: An optical switch that any vibration or oscillation transmitted to the optical switch from the outside is substantially prevented from being transmitted to a movable electrode is provided. In an optical switch comprising: a stationary electrode; a movable electrode opposed to the stationary electrode with a predetermined space therebetween; and a mirror mounted to the movable electrode, wherein the movable electrode and the mirror are moved together by applying a voltage between the stationary electrode and the movable electrode thereby to switch the path of an incident optical signal to the optical switch, a buffer member provided with a diaphragm is attached to the bottom of the stationary electrode, and a vibration or oscillation is substantially prevented from being transmitted to the movable electrode by the damping effects of the diaphragm and the space area formed above the diaphragm.

Abstract: A system for wavelength locking i.e. for maintaining a frequency of an optical signal to within predetermined limits has means for splitting part of the controlled optical signal into at least three sub-beams of which one is a reference beam and two others are provided to an optical element having a periodic output response and to a filter having a monotonic output response. The three detected outputs are analyzed and processed to determine accurately the wavelength of the optical signal and to produce a correcting signal if it is not within the predetermined limits.

Abstract: A reflective coherent spatial light modulator (RCSLM) includes a subwavelength resonant grating structure (SWS), the SWS including at least one subwavelength resonant grating layer (SWL) have a plurality of areas defining a plurality of pixels. Each pixel represents an area capable of individual control of its reflective response. A structure for modulating the resonant reflective response of at least one pixel is provided. The structure for modulating can include at least one electro-optic layer in optical contact with the SWS. The RCSLM is scalable in both pixel size and wavelength. A method for forming a RCSLM includes the steps of selecting a waveguide material and forming a SWS in the waveguide material, the SWS formed from at least one SWL, the SWL having a plurality of areas defining a plurality of pixels.

Abstract: An optical system of the present invention includes a reflective liquid crystal device having a plurality of independently activated liquid crystal elements, and an optical element for directing a plurality of input light beams at the reflective liquid crystal device such that each input light beam impinges upon one of the liquid crystal elements. Each liquid crystal element of the reflective liquid crystal device includes a transparent first electrode, a reflective second electrode spaced apart from the first electrode, and a liquid crystal medium disposed between the first and second electrodes. The liquid crystal elements are independently operable to change between half-wave and zero retardation states in response to an applied voltage.

Abstract: An electrostatically driven optical membrane comprises a support structure and a membrane structure separated from the support structure by an electrostatic cavity. Stiction plugs are formed in the membrane structure. The plugs extend from a surface of the membrane. In one implementation, the plugs are hollow to allow a subsequent release process in which the sacrificial layer is removed.

Abstract: An optical modulator includes an optical input; an optical output; at least one optical path connecting the optical input and output; and an electrode structure for selectively changing the optical characteristic of a part of the at least one optical path in response to a control signal such as to modulate light passing along the optical path. The optical path further includes a structure which slows the passage of light along the part of the optical path to enhance the modulation effect of the modulator for a given length of optical path. Preferably the structure comprises a sequence of coupled resonator structures in which each resonator structure is defined by a pair of partially reflecting planes which define an optical resonator cavity within the optical parts.

Abstract: An optical modulator and an image projection display apparatus using it can reduce a size of a system and improve efficiency, by attaching a reflection plane on a nonlinear matter. The optical modulator in accordance with the present invention includes a nonlinear matter which is divided into predetermined regions having a direction of a polarization which is periodically reversed, an electrode which is joined with the upper and lower sides of the nonlinear matter, for applying an electric field to the polarization region at the lower portion of the nonlinear matter and a reflection plane which is joined to the rear surface of the nonlinear matter, for reflect an incident light to an incident region again.

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 polaizer when reflecting light. Still other optical devices use diffusely reflecting polarizers to recycle light and improve display illumination.

Abstract: A conductive substrate supports an array of multi-channel optical attenuating devices. Each attenuating device includes a membrane with an optically transparent portion And a flexible support for positioning the optically transparent portion of the membrane spaced from the substrate for defining an air gap. The air gap constitutes a cross-shaped gap-chamber having a horizontally and vertically elongated chambers extended from a central intersection area functioning as an optical active area. A voltage bias circuit applies an electrical bias between the conductive substrate and the membrane to adjust and control an air-gap thickness at the optical active area between the conductive substrate and the membrane. Each of the devices can be manufactured on the same silicon wafer using the same process and can be individually controlled to accommodate different wavelength attenuation at each channel. Production costs, and time and efforts required for aligning the array to optical fibers are also reduced.

Abstract: The present invention relates to an electro-optic probe, which includes the following components: a laser diode for emitting a modulating laser light according to control signals generated in a main body of the electro-optic sampling oscilloscope; a first lens for converting the modulating laser light to a parallel beam; a second lens for focusing the parallel beam; an opto-electronic element having a reflection film at a reflection-end; an isolator device disposed between the first lens and the second lens for transmitting the modulating laser light and separating a reflected beam produced at the reflection film into signal beams; and photo-diodes for converting optical energies of the signal beams separated by the isolator device into respective electrical signals; wherein, the signal beams to enter the photo-diodes are directed to propagate towards the laser diode, and the photo-diodes are disposed in a longitudinal direction of a probe casing.

Abstract: A light modulator is comprised of two unit devices each using surface plasmon generated at the interface between thin metal films respectively formed on prisms and an electro-optical material, and a mirror. Both of the transmitted light due to absorption and re-radiation, and the reflected light arising from the unit devices are made into the outgoing light, the incident light on the next unit device, or the incident light on the mirror. Consequently, all light beams can be utilized as the final outgoing light beams with no loss of light. Further, the color of light can be spatially divided, and still further, it can also be temporally divided by changing the wavelength due to a voltage. As a result, the original light can be divided both temporally and spatially with almost no loss by combining two unit devices so configured as to re-radiate the absorbed light by surface plasmon using surface plasmon and a mirror, and thus utilizing both of the reflected light and the transmitted light.

Abstract: An optical device for rerouting and modifying an optical signal that is capable of operating as a dynamic gain equalizer (DGE) and/or a configurable optical add/drop multiplexer (COADM) is disclosed. The optical design includes a front-end unit for providing a collimated beam of light, an element having optical power for providing collimating/focusing effects, a diffraction element for providing spatial dispersion, and modifying means which in a preferred embodiment includes one of a MEMS array and a liquid crystal array for reflecting and modifying at least a portion of a beam of light. The modifying means functions as an attenuator when the optical device operates as a DGE and as a switching array when the optical device operates as a COADM.

Abstract: An optical imaging system including a wide-angle Cartesian polarizing beam splitter, light valve illumination optics having an f/#≦2.5, and at least one reflective light valve. The Cartesian polarizing beam splitter (PBS) has a structural orientation defining fixed polarization axes. The use of a Cartesian PBS allows the development of systems using curved PBS that provide higher light output and/or replace or augment other optical components. By recognizing and advantageously applying properties of wide-angle Cartesian polarizers, the present invention discloses a high-efficiency optical imaging system capable of functioning at f/#'s equal to or below f/2.5 while maintaining a contrast ratio of at least 100 to 1, or, more preferably, 150 to 1 in a projection system configuration.

Abstract: A film which simultaneously maximizes light reflectivity from one side of the film while maximizing light transmissivity from the opposite side of the film. This is achieved by configuring the film with distinct regions of transparency and reflectivity where the extended boundary of the reflective region is shaped into a light funnel/pipe and where periodically placed discrete and/or extended/continuous shapes are created (such as extended triangular indentations, or discrete shapes such as a cone, a pyramid, or any polyhedron). The reflective region is composed of mirror-like material such as aluminum or silver, but may be a composite paste, a composite material, or multiple materials with different refractive indices or reflective qualities. In some embodiments, the reflective material is embedded in the transparent material such that the base of each shape is approximately parallel to and coincident with, or slightly recessed from the surface of the transparent material.

Abstract: An interferometric light modulator includes a base and a ribbon suspended above the base. The ribbon has a central region and first and second conducting regions located outside of the central region. The ribbon includes a first mirror between the first and second conducting regions. The base includes a second mirror located parallel and adjacent to the first mirror so that the first and second mirrors form an interferometric cavity. An electrical bias applied to the first and second conducting regions adjusts the interferometric cavity in order to modulate light which is incident upon the central region of the ribbon. In an alternative interferometric light modulator, the light is incident upon a second central region of the base.

Abstract: A solid state device used to modulate the intensity of reflected or transmitted light by modulating with an external voltage the optical thickness of a thin film ferroelectric placed in an etalon cavity is disclosed. The device is constructed by selecting a generally planar supporting substrate, preferably silicon or sapphire in order to be compatible with silicon integrated circuits. A dielectric stack consisting of alternating layers of different index of refraction materials, also specifically selected to be compatible with later growth of the thin film ferroelectric, is deposited thereon to form a partially reflective and partially transmitting mirror, followed by a transparent electrically conductive layer. The thin film ferroelectric is deposited on the conductive layer, followed by a second transparent conductive layer and a second dielectric stack. Leads are connected to the conductive layers and in turn to a voltage generator.

Abstract: A switching array comprising a plurality of total internal reflection (TIR) switches can be used to direct optical signals from any one of a plurality of input optical fibers to any one of a plurality of output optical fibers. The TIR switches comprise electro-optic material which is surrounded by electrodes to enable the application of an electric field which causes the index of refraction of the electro-optic material to be altered. The index can be changed enough to cause a light beam incident on a boundary between the electro-optic material and an optically transmissive medium to be totally internally reflected. Free space regions exist between the input optical fibers, the switches, and the output optical fibers. Accordingly, the light from an input optical fiber to an output optical fiber travels through the TIR switch array largely, if not entirely, in free space mode. Without waveguides as interconnects within the array, fabrication is simplified.

Abstract: An Interferometric Modulator (IMod) is a microelectromechanical device for modulating light using interference. The colors of these devices may be determined in a spatial fashion, and their inherent color shift may be compensated for using several optical compensation mechanisms. Brightness, addressing, and driving of IMods may be accomplished in a variety of ways with appropriate packaging, and peripheral electronics which can be attached and/or fabricated using one of many techniques . The devices may be used in both embedded and directly perceived applications, the latter providing multiple viewing modes as well as a multitude of product concepts ranging in size from microscopic to architectural in scope.

Abstract: Method of adjusting a desired white color on at least a part of an image by means of a device comprising at least a light source and at least an electro-optical light modulation panel. The light coming from the light source is converted into an image via at least the electro-optical light modulation panel. A light control device co-operating with a light modulation panel is associated with this panel. For adjusting the desired white color, the electro-optical light modulation panel is driven through at least a part to a desired maximum. The part is imaged on the part of the image. The color of the part of the image is adapted to the desired white color by means of the light control device.

Abstract: This relates to an electro-modulating device (10) for modulating light from a light source, as part of an opto-electronic communication network. The electro-modulating device (10) has a modulating medium (16) for modulating light passing therethrough by varying an electric field applied across the modulating medium (16), an optical input-output surface (21), a light reflector (28), and electrodes (15, 17) for applying the varying electric field across the modulating medium (16). The input-output surface (21), the medium (16) and the reflector (28) are arranged so that light enters the medium (16) through the input-output surface (21), travels through the medium (16) towards the reflector (28), is reflected by the reflector (28) to travel back through the medium (16) towards the input-output surface (21), and exits the medium (16) through the input-output surface (21).

Abstract: Transflective display device having a transflector (10) which is switchable between a transparent state and a mirror-like state. Preferably, a metal hydride optical switch is used as the transflector.

Abstract: A center beam which is formed out of a thin film constituted to be combined with a light reflection film provided on one surface of the center beam, which has both ends fixed and which is deformed by an electronic force; a substrate electrode which is opposed to the center beam through a gap formed on the other surface of the center beam; an opposed surface which is a surface of the substrate electrode opposed to the center beam modulating the incident light on the light reflection film, the opposed surface restricting deformation of the center beam due to application of a driving voltage to the substrate electrode by abutting on the center beam; and a substrate which has the substrate electrode having the opposed surface, formed in a concave section, and which holds a to-be-held section of the center beam, are provided.

Abstract: Fabry-Perot filters are disclosed. having micro-electro-mechanical systems (MEMS) parts operable for tuning of the filters. The filters of the present invention are particularly useful in WDM and DWDM optical communication systems for multiplexing and demultiplexing channels of electromagnetically-carried data traversing the system. The filter can be miniaturized by etching or photolithographing the filter on silicon wafers utilizing MEMS technology. A MEMS device fabricated on the wafer is operative for moving a variably positioned mirror to change the length of the cavity or etalon of the Fabry-Perot filter, thereby tuning the filter to multiplex or demultiplex the channels.

Abstract: A collimator optical system collimates light from the coherent light source. A reflection type spatial light modulator returns collimated light from the collimator optical system to the collimator optical system. A Fourier transformation optical system Fourier-transforms light from the reflection type spatial light modulator and shares at least partial optical system with the collimator optical system. An emission light from another coherent light source passes through an incident light path composed of another collimator optical system, spatial modulator and polarized beam splitter in this order and reaches the reflection type spatial light modulator. Then, a reflection light from the reflection type spatial light modulator passes through a reflection light path which is reverse to the incident light path and reaches a polarized beam splitter. That is, the incident light path and reflection light path are split by the polarized beam splitter.

Abstract: Apparatus for increasing color resolution and quality in digital imaging systems temporally modulates red, green and blue light, detects all three colors at each pixel, and band pass filters the detected light to extract values for red, green and blue at each pixel. A detector which preserves the modulation, such as a complementary metal oxide semiconductor detector is used. Alternatively, if an integrating detector array such as a charge coupled device (CCD) is used, the three illumination sources are switched on and off sequentially, and the detector array switches to different integrating circuits for each color. Measurement of the range provides full color, three-dimensional, image data.

Abstract: The present invention discloses an optimized optical attenuator device. It includes the design of resonator formed by two identical mirrors, which are made by MEMS process. The structure realizes the minimum insertion loss. The two membranes are chosen to be with high reflection rate. Multiple layer or metal layer or mixture of them can produce membrane of high reflection rate. High reflection rate causes low tuning voltage for one certain attenuation range. To reduce the manufacture error and the cost, the two identical membranes can be formed by bonding two MEMS cells fabricated in the same process face to face. To further reduce the insertion loss, the input mode should match the residual basic mode in the resonator. The basic residual mode is the only one surviving in the resonator. A design of the resonator will guarantee this happen. Ripple is a key specification for present optical component.

Abstract: Polarization inversion domains 2 are irregularly formed in a ferroelectric substrate 3 constituting an electro-optical element 1 at least in the propagation direction of a light beam A. An A.C. current signal is applied between electrodes 4 and 5. It is thereby arranged to disturb the phase of each of the light rays constituting a light beam whose coherent characteristic is high, such as a laser light or the like, and thereby to easily obtain the light beam whose coherent characteristic has been decreased.