Abstract: An optical filter for correcting non-linear gains across a wavelength band includes a first layer having a first layer thickness according to the formula: first layer thickness=m&lgr;/(4nfirst), where m is an odd multiple integer, &lgr; is the central wavelength of the wavelength band, and nfirst is the refractive index of the first layer, and a second layer having a second layer thickness according to the formula: second layer thickness=&lgr;/(4nsecond), where &lgr; is the central wavelength of the wavelength band, and nsecond is the refractive index of the second layer. The optical filter introduces an insertion loss for wavelengths in a wavelength band of optical fiber transmission having an insertion loss curve approximating a quadratic shape in the wavelength band and having a maximum insertion loss at a central wavelength of the wavelength band.

Abstract: An optical filter including a plurality of dielectric layers is provided between first and second substrates. The substrates have a coefficient of thermal expansion that is greater than that of the dielectric layers, and the thicknesses of the substrates are selected to provide compensation for temperature-dependant variations in the center wavelength of the filter. A variety of substrate materials may be used. Quartz is advantageous as a substrate material because it has relatively low loss at wavelengths commonly used in telecommunication systems. Moreover, it is thermally and chemically stable, and has good adhesion to most dielectric films used as quarter and half wave layers. Further, quartz is mechanically tough, relatively inexpensive and readily available. The quartz substrate is cut from a crystal and has an orientation with reduced birefringence.

Abstract: An apodised refractive index grating is recorded in a photosensitive optical fiber by forming first and second component interference patterns with different pitches, that are recorded in the grating such as to result in apodisation. The component patterns are spatially in phase in a central region and move progressively out of phase towards the ends of the patterns. The patterns may be recorded sequentially or concurrently. The fiber may be stretched once or cylically.

Abstract: Variable shear A.C. interferometer based on a rotating radial grating. Light is passed through the rotating radial grating to produce multiple sidebands diffracted at various angles. These multiple sidebands produce overlapping (sheared) images of the input wavefront at a detector plane causing intensity variations proportional to the phase difference between the sheared wavefronts. An array of detectors is positioned to monitor the images on the detector plane and the outputs of each are processed to obtain the local slope of the wavefront averaged over each detector. From this data, complete wavefront slope information in one direction (X) can be obtained. By providing a second interferometer to make slope measurements in the Y direction, complete information can be obtained from which the entire input wavefront can be reconstructed.

Abstract: A virtually imaged phased array (VIPA) operating as a wavelength splitter to separate individual carriers from a wavelength division multiplexed (WDM) light. The VIPA has first and second surfaces. The second surface has a reflectivity which causes a portion of light incident thereon to be transmitted therethrough. The VIPA receives an input light at a respective wavelength within a continuous range of wavelengths. The first and second surfaces are positioned so that the input light is reflected a plurality of times between the first and second surfaces to cause a plurality of lights to be transmitted through the second surface. The plurality of transmitted lights interfere with each other to produce an output light which is spatially distinguishable from an output light produced for an input light having any other wavelength within the continuous range of wavelengths.

Abstract: The present invention provides a method and apparatus for an improved chromatic dispersion compensator. In an apparatus aspect, the present invention includes a channel separator for separating a wavelength division multiplexed light comprising a plurality of channels, the plurality of channels containing undesired chromatic dispersion and dispersion slope; and a plurality of partial-channel-set dispersion compensation devices optically coupled to the channel separator in a cascade arrangement, wherein each partial-channel-set dispersion compensation device includes: a virtually imaged phased array (VIPA) optically coupled to the channel separator, and a light returning device optically coupled to the VIPA, wherein a combination of the VIPA and the light returning device compensates for the undesired chromatic dispersion and dispersion slope by propagating each wavelength of the plurality of channels along a different path length.

Abstract: The present invention provides a method and system for dispersion compensation for a composite optical signal in an optical fiber transmission system. The composite optical signal includes a plurality of channels, each of the plurality of channels includes a band of wavelengths, where the bands of wavelengths have unwanted dispersion and dispersion slope. The present invention includes propagating the composite optical signal in a forward direction; separating the wavelengths in the band of wavelengths in each of the plurality of channels, where the each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band; spatially separating each band of wavelengths in the plurality of channels; and reflecting the spatially separated bands of wavelengths toward a return direction, where dispersion is added to the reflected bands of wavelengths such that the unwanted dispersion and dispersion slope are compensated.

Abstract: A lens for angularly overlapping a central portion of an optical beam with an outer portion of the beam is disclosed. The lens comprises a lens body having an optical axis, a rear surface on said lens body for receiving an optical beam, and a front surface on said lens body that includes inner and outer portions. The outer surface portion is inclined at a greater angle from the optical axis than the inner surface portion so that the outer portion of a beam transmitted through the lens from its rear surface to said outer surface portion is refracted by a lesser angle than an inner portion of the beam which reaches said inner surface portion.

Abstract: A method and circuit is disclosed wherein two waveguides coupled to an optical resonant ring resonator are further coupled such that beams propagating therein interfere with one another to provide a desired output response. In one embodiment, multiplexed channels of light can be demultiplexed by the device described heretofore, or alternatively, the phase relationship between these two beams can be altered prior to their being combined to provide, for example, a linearized output response useful in applications such as wavelength locking. By varying the reflectivity of the FSR and the coupling ratios and/or by varying the phase relationship between the two beams, a variety of desired output responses can be realized.

Abstract: Optical gratings having a range of possible Bragg wavelengths can be produced using a single phase mask by exposing the mask to a non-collimated spatially filtered beam of light. A spatial filter removes high spatial frequency components from the beam, and a focusing system directs the filtered beam to a phase mask. A rate at which the beam is focused and a spacing between the phase mask and a photo-sensitive waveguide are varied to produce gratings in the waveguide having a range of possible periods.

Abstract: Pattern-recognition computing can be accomplished using wave-type or other types of energy. In pattern-recognition computing which uses a plurality of wave-type energy input patterns modulated with quantized information, energy from the patterns combines to produce interference-based dynamic images. Component parts of a dynamic image are separated and recombined to produce logic and other computing process outputs. To produce a coordinated set of optics for pattern-recognition computing, waveforms at pixel-sized image components of the dynamic image are chosen to become contributors to the combined output if they will contribute (or can be modified to contribute) in a positive manner to a combined output waveform that obeys the logic rules of the device being produced. Iterative changes in input pattern characteristics are used to optimize the coordinated optics. Pattern-recognition computing can also use special interference and frequency-multiplexed logic.

Abstract: A microscopy and apparatus capable of obtaining superresolution, and a fringe projection light-cut microscopy and apparatus capable of obtaining a natural light-cut image and enabling real-time observation. At the component separating step, a plurality of modulated images of an observation object (O) are formed by subjecting the observation object (O) to spatial modulation including a plurality of modulation components while varying the component ratios of the modulation components by moving a diffraction grating (21), which modulates the observation object (O), to a plurality of different positions. The modulated images are detected with an image pickup device (22). Modulated image components corresponding to the modulation components are separated from the number of modulated images that is not less than the number of the modulation components by using linear computation. At the component demodulating step, at least one of the separated modulated image components is demodulated.

Abstract: A dense wavelength division multiplexer for the separating of an optical signal into optical channels is provided. The dense wavelength division multiplexer of the present invention includes a mechanism of inputting an optical signal where the optical signal contains a plurality of optical channels; a mechanism of separating one or more of the plurality of optical channels by introducing a phase difference between at least two the channels of the optical signal; and a mechanism for outputting the separated plurality of channels along a plurality of optical paths. The mechanism of separating one or more of the plurality of optical channels includes utilizing glass blocks and a nonlinear interferometer. The present invention provides an ease in alignment and a higher tolerance to drifts due to the increase in the width of the pass bands. It may also be easily modified to perform the add/drop function as it separates channels.

Abstract: The invention relates to a phase annulus consisting of a phase shifting thin-film system, which, in the case of a cemented system, has the following structure: (first) substrate-Ag-nH-cement-(second) substrate, or a structure: (first) substrate-n1-Ag-n2-cement-(second) substrate. In the case of an uncemented structure, the thin-film system has the following structure: substrate-Ag-nH-air, wherein nH, n1 or n2 represent the respective refractive index of a dielectric film. Phase shifting of the positive phase contrast can be regulated in a targeted manner.

Abstract: An amplitude mask, and an apparatus and method for manufacturing a long period grating filter using the same, are provided. When a long period grating is manufactured by selectively passing laser light to an optical fiber, the amplitude mask periodically passes laser light to the optical fiber. The amplitude mask includes two masks having periodically alternating pass areas for passing the laser light and nonpass areas for preventing passing of the laser light, the two masks being continuously rotated in opposite directions. The period of the pass area thus continuously changes. In this mask, two masks each having a predetermined period are rotated in opposite directions, to thus provide an amplitude mask period depending on the angle of rotation. Thus, the period of the amplitude mask can be continuously changed.

Abstract: A method for tuning a dielectric filter comprises determining filter characteristics of a filter including a cut-on wavelength and a cut-off wavelength taken at a selected gain level. The filter is rotatably attached to a collimator assembly and a light source having a wavelength approximately equal to the cut-on frequency is applied to the filter and rotated to adjust the filter to the cut-on wavelength, and the spectral performance is measured and compared with a cut-on rating value. The method further includes applying a light signal having a wavelength set to a cut-off wavelength, to the filter rotating the filter relative to the collimator assembly, measuring spectral performance, and comparing the measured spectral performance with a cut-off rating value.

Abstract: An angular dispersive device acts as a virtually imaged phased array (VIPA) which receives an input light, and produces a spatially distinguishable output light in accordance with the wavelength of the input light. First, second and third lenses are arranged in order to focus the input light into the angular dispersive device. The characteristics of the first, second and third lenses are determined to provide an increased beam width in a top view of the output light produced by the angular dispersive device. The first lens collimates the input light in a side view and has no lens effect in a top view. The second lens receives the input light from the first lens, and focuses the input light in the side view and has no lens effect in the top view. The third lens receives the input light from the second lens, and collimates the input light in the top view and has no lens effect in the side view. The angular dispersive device has first and second surfaces.

Abstract: An optical film comprising a plurality of layers wherein the refractive index difference between the layers along at least one in-plane axis is greater than the refractive index difference between the layers along an out-of-plane axis. The film has an average reflectivity of at least 60% for a predetermined bandwidth of light incident at 60.degree. from normal to the plane of the film, said light being polarized in a plane defined by the at least one in-plane axis and the out-of-plane axis.

Abstract: Boron containing glasses are sensitive to radiation in the band 225-275 nm and therefore, B.sub.2 O.sub.3 glasses are particularly adapted to receive refractive index modulation, e.g., to make reflection gratings. Glasses containing SiO.sub.2 and B.sub.2 O.sub.3 are particularly suitable when the grating is to be localized in the cladding of a fibre. Glasses containing SiO.sub.2, GeO.sub.2 and B.sub.2 O.sub.3 are suitable when the grating is in the path region of a waveguide, e.g., in the core of a fibre.

Abstract: Optical devices such as light pipes which incorporate multilayer optical films in which the refractive indices of two adjacent layers in the thickness direction are substantially matched or are small relative to the difference in refractive indices of said two adjacent layers in an given in-plane direction which is at least 0.05.

Abstract: A technique for introducing variable phase delay across portions of a spatially coherent light beam, such as a laser, without changing the focal length of the portions of the beam. A fly's-eye lens array is utilized to distribute the light for a more uniform illumination, but different length air gaps are introduced in the lens elements to provide a variable delay of portions of the beam. In a second scheme, a set of prisms is positioned in the path of the laser beam, in which the shape of the prism introduces variable phase delay across the cross-section of the beam.

Abstract: A method of producing an optical element including a photopolymer layer between two holograms is disclosed. The holograms have the same diffraction spacing and refractive index, but the first hologram has an efficiency of about one-half that of the second hologram, preferably about fifty per cent and ninety-five per cent respectively. The photopolymer is polymerized to adjust the refractive index of the photopolymer until output beams will overlap and cancel each other.

Abstract: An interference filter (10, 30, 50, 70, 90, 110, 130, 150, or 190) filters selected wavelengths by dividing an input beam into two or more intermediate beams having different optical path lengths and by recombining the intermediate beams into an output beam that is modified by interference between the intermediate beams. An optical path length difference generator (20, 40, 60, 80, 100, 120, 140, 160, or 200) varies the optical path lengths of the intermediate beams by changing the physical lengths of their paths or the refractive indices of the mediums in which they are conveyed. The optical path length generator (20) of one exemplary embodiment (10) includes a spacer plate (20) that is divided into elements (22 and 24) having different refractive indices for varying the optical path lengths of the intermediate beams.

Abstract: An operation microscope includes an illuminating device and an interference filter in the illuminating beam of the illuminating device. The interference filter is suitable for incorporation into the operation microscope. In order to prevent the yellow tinge that is present in long-known UV interference filters, the interference layer applied directly to the carrier substrate is a layer between 8 and 12 nm thick of yttrium fluoride, thorium fluoride, lanthanum fluoride or cerium fluoride.

Abstract: A virtually imaged phased array (VIPA) operating as a wavelength splitter to separate individual carriers from a wavelength division multiplexed (WDM) light. The VIPA has first and second surfaces. The second surface has a reflectivity which causes a portion of light incident thereon to be transmitted therethrough. The VIPA receives an input light at a respective wavelength within a continuous range of wavelengths. The first and second surfaces are positioned so that the input light is reflected a plurality of times between the first and second surfaces to cause a plurality of lights to be transmitted through the second surface. The plurality of transmitted lights interfere with each other to produce an output light which is spatially distinguishable from an output light produced for an input light having any other wavelength within the continuous range of wavelengths.

Abstract: A double Bessel beam is produced such that two Bessel beams are superimposed on each other with respect to amplitude so as to interfere with each other. Each of the Bessel beams has a shape of the zero-order bessel function of the first kind and a light amplitude distribution different in diameter from that of the other. An apparatus for producing a double Bessel beam includes a device for producing two Bessel beams each having a shape of the zero-order Bessel function of the first kind and a light amplitude distribution different in diameter from the other, and a device for superimposing the two Bessel beams on each other with respect to amplitude so as to interfere with each other.

Abstract: A spectral filter is made in the form of a wafer of nanochannel glass having an array of substantially uniform parallel hollow channels of from about 0.1 microns to about 10 microns that are coated with a reflective material.

Abstract: A head mounted display in which ambient light is used to illuminate a display to at or near the brightness of the scene being viewed when both reach the user's eyes. A small supplemental light source may further be used to increase the range of operation of the display when ambient light levels are insufficient to make the display screen viewable.

Abstract: An optical logic device is provided by an interferometer having an output which defines a logic state 1 or 0 in dependence upon an interference condition existing in the interferometer. Each arm of the interferometer contains a semiconductor optical amplifier in which the effect of cross phase modulation is utilized to modulate the phase of light transmitted through the respective arms. Optical signals are counter propagated through one or both of the arms in order to provide the cross modulation and thereby enable the interference condition to be set to one or other of the logic states. Automatic level control is provided at inputs to the interferometer and between successive stages of logic device. The method has application to high frequency digital optical communication systems where all optical logic operations are required.

Abstract: A virtually imaged phased array, or "wavelength splitter", which receives a wavelength division multiplexed light including at least two carriers and produces a spatially distinguishable output light for each carrier. The virtually imaged phased array includes a transparent material having first and second surfaces thereon. The second surface has a reflectivity which allows a portion of light incident thereon to be transmitted therethrough. The wavelength division multiplexed light is reflected a plurality of times in the transparent material between the first and second surfaces to cause a plurality of lights to be transmitted through the second surface. The plurality of transmitted lights interfere with each other to produce a respective output light for each carrier of the wavelength division multiplexed light.

Abstract: An apparatus which combines a virtually imaged phased array (VIPA) with a demultiplexer, to provide a large bandwidth, high resolution wavelength demultiplexer. Generally, a VIPA is a device which receives an input light having a respective wavelength within a continuous range of wavelengths, and causes multiple reflection of the input light to produce self-interference and thereby form an output light. The output light is spatially distinguishable from an output light formed for an input light having any other wavelength within the continuous range of wavelengths. The apparatus combines the VIPA with a demultiplexer, such as a diffraction grating. More specifically, the VIPA receives an input light and produces a corresponding output light propagating away from the VIPA. The output light includes a plurality of different wavelength components.

Abstract: An apparatus which can be referred to as a Virtually Imaged Phased Array (VIPA). The apparatus receives an input light and produces a spatially distinguishable output light in accordance with the wavelength of the input light. The apparatus includes first and second surfaces separated from each other with air in between. The second surface has a reflectivity which allows a portion of light incident thereon to be transmitted therethrough. The first and second surfaces are positioned so that the input light is reflected a plurality of times between the first and second surfaces through the air to cause a plurality of lights to be transmitted through the second surface. The plurality of transmitted lights interfere with each other to produce the output light.

Abstract: An apparatus which adds "opposite dispersion" to light, to compensate for chromatic dispersion of the light caused by travelling through an optical fiber. The apparatus includes a virtually imaged phased array (VIPA), and a light returning device. The VIPA provides angular dispersion to the light, and the light returning device returns the light back to the VIPA to undergo multiple reflection inside the VIPA. The light returning device is typically a mirror. In this case, the mirror can be shaped so that the apparatus adds a constant dispersion to the light.

Abstract: A method of forming a reflective polarizer comprising orienting a multilayer film formed from alternating layers of a first polymeric material and a second polymeric material in a first in-plane axis direction while allowing dimensional relaxation in an orthogonal second in-plane axis direction to produce specified differences in the refractive indices of the first and second polymeric materials in the first and second in-plane directions and in the thickness direction.

Abstract: Method and apparatus are provided for a general purpose photonic computer. A data signal is input through an encoder to encode such signal with an instruction. The encoded signal is transmitted by means of a laser beam to an input buffer where it interferes with a reference beam so as to form an interference pattern therein as a hologram, IPH. A read beam is directed through the IPH and through a decoder which reads the instruction as having, e.g. an OP Code, data source and destination. The decoded instruction is forwarded on the read beam to ALU spin media which respond to the instruction by flipping spins between two energy levels, in one or more sequences of data patterns which are read or measured by one or more sensors. Such sensors can be RF, microwave or optical sensors, which sensors output Radix=2 or digital data signals for, e.g. storage, display or further processing as desired.

Abstract: An apparatus which adds "opposite dispersion" to light, to compensate for chromatic dispersion of the light caused by travelling through an optical fiber. The apparatus includes a virtually imaged phased array (VIPA), and a light returning device. The light returning device is typically a mirror. The VIPA provides angular dispersion to the light, and the light returning device returns the light back to the VIPA to undergo multiple reflection inside the VIPA.

Abstract: A laser imaging system having contemporaneous laser/white light viewing such that substantially only the wavelength of the spectral line of the laser light of the confocal portion of the laser imaging system is blocked by a holographic notch filter positioned in front of the white light image capture device (e.g., a video or CCD camera) to provide a white light image characterized by the natural white light image having been preserved and whereby substantially all of the reflected white light spectrum is transmitted by the holographic notch filter. In a second aspect of the invention, a novel bright field cube includes a beam splitter dimensioned to effectively eliminate the contrast bands typical of laser confocal images of the prior art resulting from interference fringes in the beam splitter to provide enhanced image detail of specimen structures.

Abstract: Birefringent multilayer optical films in which the refractive indices in the thickness direction of two adjacent layers are substantially matched have a Brewster angle (the angle at which reflectance of p-polarized light goes to zero) which is very large or is nonexistant. This allows for the construction of multilayer mirrors and polarizers whose reflectivity for p-polarized light decreases slowly with angle of incidence, are independent of angle of incidence, or increase with angle of incidence away from the normal. As a result, multilayer films having high reflectivity (for both planes of polarization for any incident direction in the case of mirrors, and for the selected direction in the case of polarizers) over a wide bandwidth, can be achieved.

Abstract: An interference filter (10, 30, 50, 70, 90, 110, 130, 150, or 190) filters selected wavelengths by dividing an input beam into two or more intermediate beams having different optical path lengths and by recombining the intermediate beams into an output beam that is modified by interference between the intermediate beams. An optical path length difference generator (20, 40, 60, 80, 100, 120, 140, 160, or 200) varies the optical path lengths of the intermediate beams by changing the physical lengths of their paths or the refractive indices of the mediums in which they are conveyed. The optical path length generator (20) of one exemplary embodiment (10) includes a spacer plate (20) that is divided into elements (22 and 24) having different refractive indices for varying the optical path lengths of the intermediate beams.

Abstract: This invention provides a thermoplastic multilayer resinous film in which two or more resinous materials form a plurality of very thin layers of substantially uniform thickness, the layers being substantially parallel, the contiguous adjacent layers being of different transparent thermoplastic resinous materials differing in refractive index, each of the outermost skin layers being at least 5% of the total thickness of the film and the multilayer film containing a sufficient quantity of a pearlescent pigment in at least one of the interior layers to render it non-glossy.

Abstract: A modulated index lens containing a subsurface zeroth order coherent microlenticular mosaic defined by an index gradient adds a normalizing function to the vergences or parallactic angles of incoming light rays subtended from field object points and redirects them, in the case of near-field images, to that of far-field images. Along with a scalar reduction of the lense's linear focal range, this results in an extreme depth of field with a narrow depth of focus and when used as an intraocular lens (IOL) or contact lens avoids the focal split-up, halo, and inherent reduction in contrast of multifocal IOLs and multifocal contact lenses. A high microlenticular spatial frequency, which, while still retaining an anisotropic medium, results in a nearly total zeroth order propagation throughout the visible spectrum.

Abstract: Substantial improvements in photorefractive device lifetimes are provided by control of electron migration which results in the decay of gratings in photorefractive materials due to diffusion and other effects. A new class of photorefractive devices using compensating electronic and ionic gratings having relatively low efficiency but nonetheless usable gratings is provided by arranging the gratings to be reflective in a wavelength band outside the photo-excitation band of the photorefractive material, as by using an infrared operating wavelength. Longer lifetimes in high efficiency gratings are achieved by constant or periodic illumination of photorefractive materials to assure uniform charged distribution of electrons and maintenance of the ionic backbone grating.

Abstract: Pattern-recognition computing can be accomplished using wave-type or other types pf energy. In pattern-recognition computing which uses a plurality of wave-type energy input patterns modulated with quantized information, energy from the patterns combines to produce interference-based dynamic images. Component parts of a dynamic image are separated and recombined to produce logic and other computing process outputs. To produce a coordinated set of optics for pattern-recognition computing, waveforms at pixel-sized image components of the dynamic image are chosen to become contributors to the combined output if they will contribute (or can be modified to contribute) in a positive manner to a combined output waveform that obeys the logic rules of the device being produced. Iterative changes in input pattern characteristics are used to optimize the coordinated optics. Pattern-recognition computing can also use special interference and frequency-multiplexed logic.

Abstract: A means and method for phase stabilization and sorting of wavetrains of electromagnetic energy comprising: splitting an input beam into a plurality of intermediate beams; directing the intermediate beams along separate delay paths so that wavetrains from the delayed beams overlap each other and bridge gaps between wavetrains; producing interference with the delayed beams at a plurality of locations at an image component separator, and separating energy at each location, phase-adjusting and directing it into at least one output, thereby providing a wavetrain phase stabilizer having a substantially constant phase output by phase-matching overlapping wavetrains. Multiple outputs may be added to facilitate wavetrain sorting. Inserting the invention into the feedback path of a laser provides phase-stabilized continuous-wave laser light.

Abstract: A means and method of photonic heterodyning wherein at least one photonic beam set having fundamental frequencies to be heterodyned is used to produce a dynamic interference image that is projected onto an image component separator. Energy from selected portions of the dynamic image is separated into at least one output. Energy components within the dynamic image move relative to the separating locations as determined by the fundamental input frequencies. This causes intermodulation of the input signals and the development of energy at the sideband frequencies in the output(s). Special Interference is also used to provide amplified photonic heterodyning.

Abstract: A means and method of controlling a plurality of energy beams with at least one of the plurality of beams. At least one first beam set produces special interference with at least one second beam set, at a first location(s), diverting energy from both beam sets to a second location(s), where energy does not appear from one . . . or either, of the inputs in the absence of interference. By selecting the timing, levels, phases, frequencies, and interconnection of multiple controllers, a multitude of useful energy beam circuits are able to be made . . . such as: gated amplifiers, cascaded amplifiers, gated oscillators, phase demodulators, active filters, inverters, inverted filters, limiters, threshold detectors . . .

Abstract: A photosensitive optical body is exposed by a diverging three-dimensional standing wave interference pattern generated by a holographic projector system. The projector system, using binary optics, creates a diverging lattice of hexagonal or square rod-like intensity maxima extending through the optical body. After the standing wave image is recorded and fixed, the optical body will contain a honeycomb-like grid or pattern that will cause either an absorption or a refractive index modulation effect on light that differs in incidence to the direction of normal propagation through the created channels to a focus or convergence point. This produces either a volume-absorption hologram or a volume-phase hologram (transmittance function modulated by the permittivity [index of refraction]) with such properties as depth of focus, high resolution, and a one-way (directional perspective) and anti-glare effect with reduced diffraction.

Abstract: A means and method of controlling a plurality of energy beams with at least one of the plurality of beams. At least one first beam set produces special interference with at least one second beam set, at a first location(s), diverting energy from both beam sets to a second location(s), where energy does not appear from one . . . or either, of the inputs in the absence of interference. By selecting the timing, levels, phases, frequencies, and interconnection of multiple controllers, a multitude of useful energy beam circuits are able to be made . . . such as: gated amplifiers, cascaded amplifiers, gated oscillators, phase demodulators, active filters, inverters, inverted filters, limiters, threshold detectors . . .

Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering and for signal processing applications. The systems utilize an interferometer configuration. A first optical modulator in a first leg of the interferometer is used to modulate coherent light with the signal to be delayed. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a stack of lens pairs or diffractive optical elements or a holographic optic element may be used in place of the prism stack. The modulated optical signal from the first leg interferes on an array of photodiodes with the reference waves from the second leg.

Abstract: A means and method for performing frequency-multiplexed logic, amplification, and energy beam control functions on individual channels simultaneously within a single device by using a plurality of frequency-multiplexed inputs each having beam sets of matching channel frequencies and simultaneously producing a set of interference images, one for each channel, and separating energy from the images to produce a frequency-multiplexed output. The individual functions performed on individual channels are the result of constructive and destructive interference within each channel's image.