Abstract: An optical switching system comprising an embodiment with a high pass filter operable to eliminate a portion of frequencies present in an image and an optical device operative to receive the spectrally modified image from the high pass filter, alternatively amplify the spectrally modified image, and propagate at least those frequency components in the spectrally modified image exhibiting a frequency less than an absorption frequency of the optical switching device when the optical switching device is active. Alternatively, the optical switching system may transmit an image only when the system is active. The optical switching system may, for example, comprise superluminescent light emitting diodes which may be, for example, formed in the shape of an inverted truncated prism. For human viewing purposes, the operative transmission ranges may closely coincide with the maximum sensitivity of the photopic response of the corresponding red, blue and green cones in human eyes.

Abstract: The current disclosure is directed to labels and tags that employ two-dimensional arrays of self-parallelizing interferometric modulators (“SPIMs”) to display digits, characters, and other symbols. Each SPIM functions as a discrete display element, containing a plurality of electrodes disposed on a bottom plate, a fixed top plate, and a movable plate separated by a cavity. Appropriate voltages are applied to the electrodes to vary the cavity depth of the SPIM in order for the SPIM to reflect a color of a particular wavelength or for the SPIM to appear black or white. The arrays of SPIMs are manufactured from three continuous layers using laser-based fabrication methods.

Abstract: A high sensitivity transient grating ultrafast radiation to optical image converter is based on a fixed transmission grating adjacent to a semiconductor substrate. X-rays or optical radiation passing through the fixed transmission grating is thereby modulated and produces a small periodic variation of refractive index or transient grating in the semiconductor through carrier induced refractive index shifts. An optical or infrared probe beam tuned just below the semiconductor band gap is reflected off a high reflectivity mirror on the semiconductor so that it double passes therethrough and interacts with the radiation induced phase grating therein. A small portion of the optical beam is diffracted out of the probe beam by the radiation induced transient grating to become the converted signal that is imaged onto a detector.

Abstract: An electro-optic modulator for the modulation of optical radiation of a predetermined wavelength, the electro-optic modulator having at least one optical resonator in which a standing optical wave can be formed for the predetermined wavelength. In the resonator, at least two doped semiconductor sections—as seen in the longitudinal direction of the resonator—are arranged at a distance from one another, and the at least two doped semiconductor sections respectively lie locally at an intensity minimum of the standing optical wave.

Abstract: This document provides techniques, apparatus and designs for using electro-optic WGM resonators that support two different families of optical WGM modes with different quality factors in various applications. A radio frequency (RF) resonator is formed on the optical resonator and structured to supply an RF field and spatially overlaps the RF field of the RF resonator with the first and second optical whispering gallery modes to cause RF energy in the RF field at a first RF carrier frequency to couple with the first optical whispering gallery mode and RF energy in the RF field at a second RF carrier frequency to couple with the second optical whispering gallery mode.

Abstract: Optical modulator having wide bandwidth based on Fabry-Perot resonant reflection is disclosed. The optical modulator includes: a bottom Distributed Bragg Reflector (DBR) layer; a top DBR layer including at least one layer, and a modified layer; and an active layer disposed between bottom and top DBR layers, wherein the at least one layer includes at least one pair of a first refractive index layer having a first refractive index and a second refractive index layer having a second refractive index, the modified layer includes at least one pair of a third refractive index layer having a third refractive index and a fourth refractive index layer having a fourth refractive index, the third and the fourth refractive indexes being different, and at least one of the third and the fourth refractive index layers has a second optical thickness that is not ?/4 or that is not an odd multiple thereof.

Abstract: An optical deflector includes multiple voltage-dependent refractive boundaries. Light passes through the refractive boundaries and accumulates a deflection angle. An electrode placed to apply a voltage to the boundaries may be non-uniform to modulate a wavefront as it passes. A scanning laser projector includes the optical deflector to modulate laser light.

Abstract: An imaging method includes emitting radiation from an illumination source towards a total internal reflection (TIR) modulator. At least one of the pixel regions is controlled to form at least one image pixel on a surface. A first electric potential is imposed on a first pixel region, the first electric potential being associated with a first signal provided by a first electrical conductor to the second set of electrodes associated with the first pixel region, the first electrical conductor extending over a first non-pixel region. A second electric potential is imposed on the first pixel region, the second electric potential being associated with a second signal provided by a second electrical conductor to first set of electrodes associated with the first pixel region, the second electrical conductor extending over a second non-pixel region, wherein the second non-pixel region is different from the first non-pixel region, and the second electric potential is different from the first electric potential.

Abstract: Radiation from an illumination source (102) is directed to a total internal reflector (TIR) modulator (10). The modulator includes a an electro-optic member (213) with a plurality of individually addressable pixel regions (210) comprised of a plurality of electrodes arranged in a first and second set. At least one electrode of the first set is adjacent to at least one electrode of the second set and at least one of the pixel regions is controlled to form at least one image pixel on a surface. A first electric potential is imposed on the first set of electrodes selected from a first predetermined group of electric potential values. A second electric potential is imposed on the second set of electrodes selected from a second predetermined group of electric potential values. The first and second predetermined groups of electric potential values together comprise at least three different electric potential values.

Abstract: An electro-optic semiconductor device (e.g., an optical modulator) having side access and beam propagation within the device is provided. Side access for the optical input and/or output facilitates disposition of electronic circuitry and/or heat sinking structures on the top and bottom surfaces of the modulator. Internal beam propagation instead of internal waveguiding advantageously simplifies optical coupling and alignment to the modulator. Interaction length within the device is preferably enhanced by passing through the device active region at a relatively shallow angle. The internally propagating beam is reflected from a reflective face parallel to the device active region. The side faces can be perpendicular or tilted with respect to the reflective face. Tilted side faces are preferably tilted to provide external beam paths parallel to the reflective face. Internal reflection from an angled side face can be employed to provide configurations having one side port and one top or bottom port.

Abstract: An electro-optic semiconductor device (e.g., an optical modulator) having side access and beam propagation within the device is provided. Side access for the optical input and/or output facilitates disposition of electronic circuitry and/or heat sinking structures on the top and bottom surfaces of the modulator. Internal beam propagation instead of internal waveguiding advantageously simplifies optical coupling and alignment to the modulator. Interaction length within the device is preferably enhanced by passing through the device active region at a relatively shallow angle. The internally propagating beam is reflected from a reflective face parallel to the device active region. The side faces can be perpendicular or tilted with respect to the reflective face. Tilted side faces are preferably tilted to provide external beam paths parallel to the reflective face. Internal reflection from an angled side face can be employed to provide configurations having one side port and one top or bottom port.

Abstract: A light managing screen may provide a rear projection screen, front projection screen or component thereof. The screen may comprise a polymeric composition including a first polymeric material, and a second polymeric material disposed as a plurality of elongated structures within the first polymeric material. Each elongated structure has a major axis and the major axes are substantially aligned. The first polymeric material has an index of refraction that differs by at least 0.01 from an index of refraction of the second polymeric material. In some instances, a pressure sensitive adhesive material is selected as the first polymeric material. The orientation of the elongated structures and the difference in indices of refraction results in the polymeric composition scattering light asymmetrically.

Abstract: The invention relates to the combination of lower transmittance etalons with higher transmittance filters, including use of a single circular polarizer with high efficiency and optical performance for its filtered polarization, to achieve necessary throughput of a narrow bandpass region. The lower transmittance etalons can be achieved by using lower transmittance solid-state etalon materials, or by control of the coatings on the etalon. Alternate configurations are described that reduce the optical assembly's footprint, and/or include additional filters to remove stray light. An innovative option to heat the etalon directly is disclosed to actively stabilize and maintain the etalon's bandpass.

Abstract: A display device comprising the following arranged from light input side in the order listed below: a first reflector having a semi-transmissive and semi-reflective property; a translucent porous body having a plurality of pores in which a translucent material is filled, each of the pores having a substantially smaller diameter than the wavelength of input light; and a second reflector having a perfect reflection property, or a semi-transmissive and semi-reflective property. The average complex refractive index of the translucent porous body is changeable with respect to each display dot, and the wavelength of light absorbed by the translucent porous body is changeable with respect to each display dot according to the average complex refractive index. In this way, the input light is modulatable, and the modulated light is outputted from the first reflector and/or the second reflector to perform image display.

Abstract: A contained resonant cavity. The contained resonant cavity includes a first surface and a second surface that are partially transmissive and partially reflective, One or more reflective sidewall, are positioned between the first surface and the second surface. In a specific embodiment, the first surface and the second surface are substantially parallel and represent input and output surfaces, respectively, of the contained resonant cavity. The one or more sidewalls are approximately perpendicular to the first surface and the second surface and include a first sidewall having a first substantially reflective planar surface that faces a second substantially reflective planar surface of the second sidewall. A third sidewall and a fourth sidewall have fourth and fifth substantially reflective Lacing sidewalls, respectively.

Abstract: Prism elements having TIR surfaces placed in close proximity to the active area of a SLM device to separate unwanted off-state and/or flat-state light from the projection ON-light bundle. The TIR critical angle of these prisms is selected to affect either the off-state light or additionally, any portion of flat-state light reflected from the SLM. To further improve the optical performance of the system, these TIR prisms can be attached directly to the SLM package, completely eliminating the package window.

Abstract: Illumination exposure control systems comprising reflective pixelated spatial light modulators that reflect substantially all of the light impinging on them into at least two different light paths. At least one of the light paths acts as a propagating light path and transmits the light beam out of the lighting system. At least one other light path acts as a non-propagating light path and prevents the light beam from being transmitted out the system. The illumination exposure control systems provide high speed of exposure actuation and precision control of exposure duration and frequency or exposure sequences.

Abstract: A correlation filter is provided having passbands at wavelengths corresponding to the absorption spectrum of an atmospheric gas of interest. In particular, the correlation filter features narrow, non-linearly spaced passbands having center wavelengths that are correlated to the non-linearly spaced absorption lines of an atmospheric gas. A correlation filter in accordance with an embodiment of the present invention includes a compensation stack having a number of thin film layers, at least some of which have an optical thickness that is not equal to an integer multiple of one-quarter of a wavelength of an absorption line of the gas of interest. The correlation filter may be provided in association with an etalon, or may comprise a number of optical cavities.

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: An apparatus for filtering electromagnetic waves and sensing deposition of chemical species, the apparatus having a substrate having a surface relief structure containing at least one dielectric body with physical dimensions smaller than the wavelength of the filtered electromagnetic waves, such structures repeated in a two dimensional array covering at least a portion of the surface of the first substrate. The apparatus may include one, two, or more such arrays, spaced from one another to create one or more cavities between the arrays.

Abstract: An optical device for receiving input light and for acting on the input light to produce output light includes a first reflector and a second reflector supported in a spaced-apart, confronting relationship with the first reflector such that the input light received by the optical device, at least potentially, undergoes multiple reflections between the first and second reflectors. At least a selected one of the first and second reflectors is configured to subject each one of a plurality of different portions of the input light to one of a plurality of different reflectance values to produce an emitted light passing through at least the selected reflector in a way which is combinable to generate the output light.

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: Among other things, a cavity having a cavity dimension is configured so that the cavity dimension changes in response to electrostatic forces applied to the cavity, and at least two electrical structures are configured to apply electrostatic forces in the vicinity of the cavity, the electrical structures being independently controllable.

Abstract: A micro-opto-electro-mechanical systems (MOEMS) modulator based on the phenomenon of frustrated total internal reflection (FTIR). The modulator effects amplitude and phase modulation at the boundary of a waveguide. Wavelength-specific switching is achieved by spatially separating the wavelength channels by dispersing a broadband input signal into its wavelength components through a grating. In exemplary embodiments, an array of micro-fabricated actuators is used to switch or modulate wavelengths individually. Applications include wavelength and space-resolved phase and amplitude modulation of optical beams, and re-configurable add/drop switching of dense wavelength-division multiplexed (DWDM) optical communication signals.

Abstract: An optical scanning apparatus which is improved in color registration by reducing bow of a scan line which is formed on a photosensitive medium. A plate having a slit with a width appropriate for a spot size of a scan line and a length corresponding to a predetermined scanning length is interposed between the photosensitive medium and a spot forming apparatus. A light source emits a laser beam, a rotary polygonal mirror reflects light from the light source while being rotated, f-&thgr; lenses cause the light reflected from the rotary polygonal mirror to form a proper spot, and a reflecting mirror disposed on an optical path between the f-&thgr; lenses and the photosensitive medium directs the spot toward the photosensitive medium. The slit plate passes a portion of the spot to uniformly form the scan line.

Abstract: An optical modulation element is capable of forming a reflective diffraction grating in which heights of a plurality of elements each having a reflecting surface periodically change. The reflecting surfaces of at least one of the plurality of elements are driven in a direction of height by piezoelectric elements. The plurality of elements each having the surface as the reflecting surface are two-dimensionally arrayed by juxtaposing long sides. A rear surface side of an effective reflecting portion of each of the elements is fixed to the piezoelectric element.

Abstract: A light modulating or switching array (10) having a plurality of discrete protrusions (16) formed of electro-optic material, each of which is electrically and optically isolated from each other. The protrusions (16) have defined a top face (20), a bottom face (30), first and second side faces (22, 24), and front and back faces (26, 28). There are a plurality of electrodes (34) associated with each of the protrusions (16), these electrodes (34) being capable of inducing an electric field in the electro-optic material for independently modulating a plurality of light beams which are incident upon one of the faces (20, 22, 24, 26, 28, 30) of the protrusions (16). The electro-optic material may be of PLZT, or a member of any of the groups of electro-optic crystals, polycrystalline electro-optic ceramics, electro-optic semiconductors, electro-optic glasses and electro-optically active polymers.

Abstract: A highly efficient electrooptic means and method of light modulation utilizing slow wave optical propagation is provided. A grating structure (35) integrated with a single mode optical waveguide (32) on an electrooptic substrate (30) induces coupling between forward- and reverse-propagating light waves. This contradirectional coupling leads to a reduction in the optical propagation speed in the forward direction. Electrodes (38a and 38b) are provided for applying an electric field to modulate the light propagating in the waveguide (32) via the linear electrooptic (Pockels) effect. In a preferred embodiment, a modulating radio frequency or microwave signal applied to the electrodes (38a and 38b) propagates in the same direction as the modulated light wave at substantially the same velocity.

Abstract: An optical modulator that modulates light through the semiconductor substrate through the back side of an integrated circuit die. In one embodiment, an optical modulator is disposed within a flip chip packaged integrated circuit die. The optical modulator includes a modulation region through which an optical beam is passed a plurality of times. In one embodiment, the optical beam enters through the back side of the semiconductor substrate at a first location and the modulated optical beam is deflected out through a second location on the back side of the semiconductor substrate. The interaction length of the optical modulator is increased by internally deflecting and passing the optical beam through the modulation region a plurality of times. In one embodiment, total internal reflection is used to deflect the optical beam. In another embodiment, reflective materials are used to internally deflect the optical beam.

Abstract: An optical fiber compatible modulator device provides high-contrast levels switchable using modest applied voltages. As a two-port optical modulator, a normal light signal incident at a first port is deflected to a non-normal direction for passage through an absorption layer (e.g., a multiple-quantum well (MQW) layer), the absorption layer having an adsorption characteristic which changes as a function of a voltage applied across it. The non-normal direction light signal exiting the absorption layer is deflected to a normal light signal for output from a second port of the optical modulator. As a one-port optical modulator, a normal light signal received at a first port is deflected to a non-normal direction for passage through an absorption layer. A reflector reflects a non-normal direction light signal exiting the layer back through the layer to the deflector means and is output at the port of the optical modulator.

Abstract: A variable spectral resolution agile filter has instantly adjustable spectral resolution with no required mechanical motion and a quickly adjustable center wavelength. Adjustment of the center wavelength is accomplished by reliable piezoelectric actuators. Adjustment of the spectral resolution is achieved by changing the finesse of the system, the finesse being governed by the reflectivity of the faces. By making one of the faces exhibit electrically variable reflectivity, the finesse of the system is instantly changeable, and thus the spectral resolution is also instantly changeable.

Abstract: The present invention relates to a novel spatial light modulator comprising a plurality of individual pixels that each contain separate detectors, electronic circuitry, and optical modulators. A primary application of such a spatial light modulator is to provide the requisite nonlinear relationship between a plurality of optical beams fanned in to each detector on the one hand, and a plurality of optical beams fanned out from such modulator on the other, on a pixel-by-pixel basis. In one embodiment, the spatial light modulator is configured to differentially amplify the inputs to two separate detectors within each pixel, and to transform iORIGIN OF INVENTIONThe U.S. Government has certain rights in this invention pursuant to Contract No. F49620-87-C0007, awarded by the Department of the Air Force, and to Grant No. AFOSR-89-0466, awarded by the Defense Advanced Research Projects Agency through the Department of the Air Force.

Abstract: The TIR modulator has an electrode array distributed across an area of the reflecting surface of the electro-optic material. The electrode array has interdigitated electrodes extending inward from a rectangular-shaped outer electrode conducting block and outward from a diamond-shaped inner electrode conducting block. A diamond-shaped area with no electrodes is preferably symmetrically within the inner electrode conducting block of the electrode array on the reflecting surface. The uniform voltage difference between the electrodes and the varying lengths of the electrodes creates a fringe electrical field in the electro-optical material and an optical phase grating to diffract the incident light on the reflecting surface. The zero order nondiffracted light becomes the output beam. The optical phase grating will control the incident beam's optical profile at the modulator (near field) and hence the imaged spot size at a focus at the image plane (far field).