Abstract: Highly efficient diffusely reflecting multilayer mirrors diffusely reflect light incident upon them. Highly efficient diffusely reflecting multilayer polarizers diffusely reflect light of one polarization while diffusely transmitting the other polarization. The diffusely reflecting mirror includes a light diffusing element and a multilayer mirror element. The diffusely reflecting polarizer includes a light diffusing element and a multilayer reflective polarizing element.

Abstract: An improved polarization beam splitter formed by a collimator and two similarly shaped, birefringent crystal prisms is provided. The light from the collimator is incident upon the first face of the first birefringent crystal prism which also has second and third faces. The collimated light is incident upon the second face at an angle .phi. with respect to a line normal to the second face so that light polarized perpendicular to a plane of incidence upon the second face is reflected toward the third face and light polarized in the plane of incidence is refracted at the second face. The second birefringent crystal prism has a second face parallel to, and in close proximity with, the second face of the first birefringent prism so that light refracted at the second face of said first prism is refracted at the second face of the second prism and into the second prism.

Abstract: An electronic candle having a configuration to emulate that of a wax candle such as a wide cylinder votive candle. The electronic candle contains circuitry to cause emission of random light flickers when activated and a spring loaded two piece switch/timer element and candle housing to effect the activation for a predetermined period of time. Switching is adapted to be effected with position placement of the candle and relative movement between the switch timer element and the housing.

Abstract: An infrared lens assembly (16, 60 and 80) operative in the near and far infrared wavebands to focus infrared radiation at an image plane (15) of an infrared detector (18). The infrared lens assembly (16, 60 and 80) includes a focusing component (33, 63 and 83), a collecting component (37, 65 and 85) and a diffracting component (41, 67 and 87). The focusing component (33, 63 and 83) and the collecting component (37, 65 and 85) may be formed from high dispersion, low index material. The diffracting component (41, 67 and 87) may be used to correct color aberrations associated with an infrared waveband.

Abstract: A versatile lighting decoration has a display sheet fabricated from a transparent and resilient film. An outline of a predetermined shape is marked on the film and a plurality of apertures placed through and along the outline. A string of lights having multiple bulbs, each bulb fitted within a socket adapted for gripping the display sheet, is releasably secured in the apertures to generate a lighted image of the predetermined shape that may be highlighted by one or more additional strings of lights.

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: An optical element is formed as a body having two layers, at least on of which is transmissive to a selected wavelength of a light of illumination. One layer is formed with a first surface relief optical formation as a boundary thereof, and the other layer is formed on the boundary so as to have an adjacent boundary that is a second surface relief optical formation that is the conjugate of the first surface relief optical formation. The other layer also has further optical features on a surface opposite the adjacent boundary. The formation and features are preferably diffractive. The further optical features opposite the adjacent boundary is preferably a compensated conjugate of the formation at the adjacent boundary.

Abstract: A real time fingerprint verification system includes a recording device and a verification device each having a fingerprint scanner for generating a flat, dimensionally undistorted, high contrast, fingerprint image, and an intensity sensitive, spatial light modulator (SLM) for receiving and transforming the flat fingerprint image into a planar, coherent light image. In the recording device, the planar coherent light image beam of the fingerprint from the SLM is Fourier transformed, and input into a microscope objective lens system which expands the Fourier transformed beam image sufficiently to allow mechanical blocking of its central portion or order, whereupon it is directed to interact as an object beam with a reference beam from the particular coherent light source to record a holographic matched filter.

Abstract: A holographic anti-imitation method and device is provided, which can prevent a creative graphic design from unauthorized reproduction. The holographic anti-imitation method and device provides the creative graphic design as a hidden pattern in a synthesized image formed in a hologram that can be viewed only through a special viewing device. This allows the creative graphic design to be highly difficult to be reproduced by infringing parties. The synthesized image includes a background pattern visible to naked eyes and a hidden pattern merged into the background pattern which is invisible to the naked eyes. The hologram can be a dot-matrix hologram which is formed through laser means that generates two interfering laser beams to form a dot-matrix pattern of the synthesized image in the hologram. The hidden pattern can be viewed only through a special viewing device, such as a lenticular or a grate-like piece.

Abstract: The present invention provides light valves including polarizing elements in which light transmission can be controlled by rotating at least one of the polarizing elements about an in-plane axis. Although reflective polarizing elements are preferred in devices according to the present invention to reduce the problem of heat build-up, the use of absorptive or other polarizers may also be envisioned. The light valves according to the present invention may find use in any application in which the transmission of light (visible or otherwise) is to be controlled. Examples of specific applications include, but are not limited to: windows, luminaires, skylights, etc.

Abstract: A light fixture includes a base having a recess defined in the top thereof and a first passage defined through the base and communicating with the recess. Two first holes are defined through the bottom and communicate with the outside of the base. A socket has a head portion inserted in the recess and a shank portion which extends from the underside of the head portion and inserted in the first passage. A shoulder portion is defined in the underside of the head portion and abuts the shank portion, and a second passage defined through the socket so as to receive a light therein. Two second holes are defined through the shoulder portion and communicate with the two first holes so that moisture or water in the recess or the socket will drain from the first holes and the second holes.

Abstract: A time division multiplexed laser emits two beams of the same wavelength but orthogonal polarization or two beams of different wavelengths from a single laser source for use in a multiple beam raster output scanning system. The multiple beam raster output scanning is obtained from a single raster scanning system (ROS) with a rotating mirror, beneficially a polygon mirror, and a single set of scan optics for use in single or multiple station printers. A plurality of the coaxially overlapping laser beams from the same laser source are deflected using a common mirror surface area and laser beams containing different channels of data signals are subsequently separated by a plurality of dynamic and static beam separators based on polarization or wavelength. The channels of the separated laser beams are directed onto associated photoreceptors.

Abstract: A holographic data storage apparatus having no readout lens. The apparatus has a spatial light modulator (SLM), a focusing element such as a lens, a holographic data storage material and a spatial light detector such as a CCD. The lens is located between the SLM and CCD such that the SLM is imaged onto the CCD (i.e. the positions of the SLM, lens, and CCD satisfy the lens equation). The holographic storage material is located between the lens and CCD. Preferably, the storage material is located centered upon a Fourier plane of the lens. In this case, the apparatus also has a phase mask located adjacent to the SLM. Alternatively, the storage material is located a distance away from the Fourier plane or is not centered on the Fourier plane. In yet another embodiment, the holographic storage material is located in contact with the CCD.

Abstract: A lens film is used in filtering visible, infrared, and ultraviolet light. The lens film has one or more metallized layers stacked together. Each metallized layer has a substrate with a metal coating covering one face of the substrate. One or more protecting layers are disposed over the stack of metallized layers to provide protection film. The lens film also has an ultraviolet absorbing material, such as an ultraviolet absorbing binder or substrate material. The lens film can be configured so that it meets the American National Standards Institute's shade standards for protection from harmful or intense light. The lens film can be mounted on a lens of an eye protection device. One method of mounting the lens is to provide an adhesive layer over a portion of the lens film and then binding the lens film to the lens with the adhesive layer.

Abstract: An optical scanning device includes a light source having a plurality of light-emitting portions, a deflector for deflecting a plurality of light beams emitted by the light source, optical elements for guiding the plurality of light beams emitted by the light source toward the deflector and an imaging element for guiding the plurality of light beams deflected by the deflector onto a surface to be scanned. A polarization limiting element is inserted in an optical path between the light source and the deflector so as to limit directions of polarization of the plurality of light beams.

Abstract: A system and method generate volumetric, three-dimensional displays, including displays of images or data. An apparent position of a volumetric image is translated by employing an image translation chamber with various combinations of concave and convex reflectors, mirrors, lenses, and/or holographic optical elements. A high-speed opto-mechanical shutter may also be used, as well as acousto-optic modulators (AOMs) for very high-speed intensity modulation of a coherent light beam to generate a periodic pattern of light packets or pulses. Active and passive multi-planar optical elements (MOEs) are also used in either a reflective or a transmissive mode and optionally having interposed layers of switchable liquid crystal material. A multi-planar optical sensor with interposed layers of light-sensitive material may be employed, as well as a gas imaging chamber for displaying the three-dimensional images. The system and method also allow interaction with the volumetric display of an image.

Abstract: Coma of an objective lens occurs depending on the lens-forming condition when plural disks of different substrate thickness are recorded and reproduced. An objective lens according to this invention is not influenced by the coma even if the thickness of the substrates is changed. For this purpose, a diffraction grating whose aberration is corrected is formed on the first side of an aspheric objective lens. Due to this correction, light beams having different diffraction orders, e.g. 0th order diffracted light and +1st order diffracted light, are focused respectively on two kinds of substrates of different thickness. The whole objective lens is tilted to correct its axial coma, and the tilt angle is predetermined to be substantially identical with respect to plural substrates which are different in thickness.

Abstract: Device, method, and system for recording diffractive high resolution text, pictorial, and/or other graphical information is provided which is particularly suited to recording information that would be difficult to reproduce by typical counterfeiting methods. The information recorded may be used to authenticate the recorded item, or indirectly, an item to which the recording is attached. Such items may include legal, financial and commercial instruments, credit cards, and packaging for such items as software, art, and other items where forgery of the item may be a concern. In one embodiment of the invention light is selectively passed by a shutter, and a spatial filter then cleans the beam to remove undesirable frequency components.

Abstract: A method and a system to re-align onto a detector array a holographic image of a Fourier region hologram stored in a medium, with the medium spinning around a first axis, and the hologram being generated by a reference beam and a signal beam. In generating the hologram, the reference beam is incident on the medium with respect to a second axis at a second-axis-incident angle, and a third axis at a third-axis-incident angle, such that the holographic image of the hologram when reproduced by the reference beam is aligned onto the detector array. Also, the three axes are substantially orthogonal to each other. As the medium spins, the medium's orientation can change through tilting with respect to the second and the third axes so that the holographic image when reproduced by the reference beam is not aligned onto the detector array.

Abstract: A magnet is integrally formed with a mirror surface for reflecting off a laser beam. A torsion spring holds the magnet thereon. The torsion spring is made of a shape-memory alloy. A coil generates an alternating magnetic field so as to oscillate the magnet about the torsion spring. The oscillating magnet scans the light beam.