Abstract: Used as a propagation function is a half-plane propagation function which is restricted such that it has a value only within a half plane in a predetermined direction perpendicular to a propagating axis in a plane which is perpendicular to the propagating axis. According to a convolution integration with this function, the wavefront of object light on a hologram surface is determined, whereby hologram data is produced. Thus produced hologram is read out by means of readout light. After the light with a wavefront forming the conjugate image of the object to be viewed is blocked, the image of the object to be viewed is observed.

Abstract: A reflected light differential interference microscope (100) having a birefringent optical member (B). Each birefringent optical member has a ray-separating plane (Q.sub.B) that intersects the optical axis (A2') at an intersection point (P.sub.B) at a first angle (.beta.) with respect to a reference plane (P.sub.2) oriented perpendicular to the optical axis. The microscope further includes an objective lens (113) having a focal point (F.sub.113) along the optical axis. The birefringent optical member is designed so as to be movable along a line oriented at a second angle (.gamma.) with respect to the reference plane in a manner that maintains the intersection point and the focal point substantially coincident. This allows for the color of the image (115) to be varied without degrading the image quality.

Abstract: A solar control film having low visible light transmittance and low visible light reflectance is comprised of a first sheet of transparent substrate material having deposited thereon a solar-load-reduction film for preferentially reducing infrared light energy transmitted through the film, and a second sheet of transparent substrate material having deposited thereon a thin, transparent film of metal effective to partially block light transmittance, wherein the first sheet of transparent substrate and the second sheet of transparent substrate are separated by an optically massive layer that prevents the constructive and destructive interference of reflected light. A preferred embodiment of a solar control film includes, in order, a pressure-sensitive adhesive layer, a polyethylene terephthalate layer, a Fabry-Perot interference filter layer, an adhesive layer, a grey metal layer, another polyethylene terephthalate layer, and a hardcoat layer.

Abstract: A laser scan microscope comprises a laser scanning observation optical system for irradiating a sample with a laser beam while scanning the beam over the sample, and detecting the beam transmitted through the sample by means of a detector after the beam passes through a condenser lens, an ordinary observation optical system for irradiating the sample through the condenser lens by means of an illumination lamp, so that a transmitted image of the sample is allowed to be observed, and an optical transmission fiber array having a two-pronged structure having a first optical path extending from a condenser lens-side to the detector and a second optical path extending from the condenser lens-side to the illumination lump.

Abstract: A dual purpose optical device that is convertible between binocular and stereoscope modes of operation while using a common eyepiece arrangement for both. The device includes a housing containing a pair of optic supports mounted side-by-side for lateral movement towards and away from one another. Each support preferably carries three lenses. Two lenses on each support serve as the eyepiece and are aligned in a common plane with an eyepiece opening through the housing and a rotatable mirror assembly. The assembly pivots substantially ninety degrees from opposing forty-five degree angle positions with respect to the plane through the eyepiece opening and the eye and field lenses so as to fold the lines of sight either up or down within the housing. A circular photo transparency reel is received horizontally in a slot provided on an upper side of the housing.

Abstract: A window is transparent to infrared and/or visible radiation, and is shielded against electromagnetic radiation. The window includes a substrate made of a material transparent to the selected wavelength band of radiation, and a multilayer grid pattern overlying the substrate. The grid pattern comprises a first layer of an electrically conductive material adjacent to the substrate, and a second layer of a magnetically permeable material overlying the first layer. Preferably, there is a third layer of an electrically conductive material overlying the second layer.

Abstract: In a method for evaluating the homogeneity of the refractive index of an optical member, the refractive index distribution of the optical member is measured, the measured refractive index distribution is separated into a rotationally symmetric element and a non-rotationally symmetric element in the optical axis direction before or after correction of the power element, and the rotationally symmetric element is further subjected to 2nd/4th-order element correction. Upon execution of such comprehensive evaluation, a photolithography optical member, which can realize a fine, sharp exposure-transfer pattern (e.g., a line width of 0.3 .mu.m or less) is provided.

Abstract: A lighting fixture including a fluorescent lamp and a heat conductive member. One end of the heat conductive member contacts the fluorescent lamp and extends outside of the lighting fixture through a through hole. The cool spot of the fluorescent lamp can thus be efficiently cooled irrespective of the temperatures inside the main part of the lighting fixture.

Abstract: A image intensifier binocular, so-called goggle, of the type having only one image intensifier tube (2) is working with an effective diameter of its entrance photocathode (3) below 15 mm and therefore an objective (1) having an accordingly shortened focal length. This combination will substantially increase the depth of field of the goggle and also enable a design of smaller weight.

Abstract: An endoscopic probe includes an inspection head attached to the end of a longitudinally flexible supporting line which connects it to an operating unit provided with means for moistening the line. The supporting line (2) is rigid under axial torsion, whilst the inspection head (1) is movable in axial rotation and is formed by a demountable assemblage of two parts: a permanent part (11), attached to the end of the supporting line by means of a rotary joint (10) and housing a miniaturized photography device (26), and an interchangeable part (12), fastened rigidly to said permanent part in the extension of the latter with the aid of a demountable joint (44) and comprising a parietal (lateral or axial) orifice provided with a wide angle ocular lens (23) followed by an optical line (25) for conveying the light energy picked up by said lens toward the photography device (26).

Abstract: A method of designing a spatial phase modulation element which has a plurality of hologram surfaces with mutually different phase patterns, and a spatial phase modulation element produced in the method. The spatial phase modulation element is designed to have a variable-phase medium located on one side of each of the hologram surfaces and modulating means for modulating the phase patterns of the hologram surfaces independently of each other. Further, if the number of output patterns to be obtained with the spatial phase modulation element is n and if the number of hologram surfaces is N, the spatial phase modulation element is so designed as to meet the condition n.gtoreq.N+2, N.gtoreq.2.

Abstract: Digital data bits are stored as discrete-level reflection microholograms in a multi-depth digital optical data storage system. Reference and signal beams are incident in a counterpropagating geometry on opposite faces of a tape. The reflection microholograms are stored at the coinciding focus of the reference and signal beams. The holograms are stored at the diffraction limit of high-N.A. optics, and have relatively high grating frequencies and small sizes. Dynamic aberration compensators correct for the depth-varying spherical aberration imparted to the beams by the medium. Multiple mutually-incoherent lasers are used for parallel storage and retrieval to increase data transfer rates. Achievable densities and signal-to-noise ratios are substantially higher than for index-perturbation or transmission hologram storage methods.

Abstract: An optical device, preferably in the form of a pair of folding binoculars (10) includes a front support (12) with a first optical means in the form of a pair of front lenses (25). A second optical means in the form of a pair of rear lenses (27) are supported by a rear support (14). Both the front support (12) and the rear support (14) are pivotably mounted to a spacing means (16) extending between the front support (12) and the rear support (14). The supports (12,14) are pivotably mounted to the spacing means (16) about respective mounting edges (17,18). The supports (12,14) each have a free edge (20,22) located opposite the respective mounting edges (127,18), enabling the support (12,14) to be folded from an operative configuration to a storage configuration. The optical device (10) may also include a releasable holding means (35, 36, 37, 38, 39, 39a, 39b) to hold the front support and the rear support in the operative configuration.

Abstract: A thorium-free low absorption coating for infrared CO.sub.2 laser optics comprises an interior BaF.sub.2 layer formed on a substrate and an exterior layer formed over the interior layer to a predetermined thickness sufficient to substantially prevent water adsorption by the interior layer. Generally, the predetermined thickness is greater than about 11000 .ANG., and in one embodiment of a two-layer low absorption coating designed for antireflection at 10.6 microns, the exterior layer has a physical thickness in a range between about 24600 .ANG. and 22800 .ANG., and preferably about 24000 .ANG.. In the preferred two-layer AR coating embodiment, the exterior layer defines a cover layer and an absentee layer, and the interior layer is relatively thin. The preferred exterior layer and the preferred substrate consist essentially of ZnSe. Multilayer stacked coatings of more than two layer can also be formed to provide low absorption partially reflective or totally reflective coatings as well as AR coatings.

Abstract: A 3-D photo attachment for the phototube of a light microscope which enables a 2-D camera port to be enhanced to take 3-D stereo pair photography both sequentially and simultaneously.

Abstract: Disclosed is a diffractive optical element which includes a diffractive grating pattern on a base plate. The diffractive grating pattern includes a plurality of phase gratings arranged in parallel lines extending along a predetermined direction to cause diffraction of an incident beam. Each of the plurality of phase gratings has an asymmetrical phase pattern. There is a phase gap, .DELTA.P, representing a phase difference (in radians) between an end point and a beginning point of each phase pattern. The phase gap, .DELTA.P, is substantially equal for each of the plurality of phase gratings and satisfies the relationship0.7.pi.<.vertline..DELTA.P.vertline.<1.2 .pi..

Abstract: A filter (10) for selectively transmitting electromagnetic energy over a range of frequencies (28, 30, 32) adapted for use with white light (24). The filter (10) includes rugate layers (18, 20) for creating a resonant cavity that resonates at desired bandpass frequencies (28, 30, 32). An absorptive layer (12) absorbs frequencies near the bandpass frequencies (28, 30, 32) and reflects frequencies outside the bandpass frequencies (28, 30, 32). Phase matching layers (14, 16) allow the transmission of electromagnetic energy within the transmission bands (28, 30, 32) through the absorption layer 12. In an illustrative embodiment, the bandpass frequencies (28, 30, 32) comprise the three tristimulus frequencies, i.e., red (28), green (30) and blue (32) frequencies. The rugate layers (18, 20) include first (18) and second (20) rugate layers made of SiO.sub.2 and Ta.sub.2 O.sub.5, respectively.

Abstract: An X-Y table of a microscope includes an a X-axis moving plate, an object holder mounted on an upper surface of the X-axis moving plate, a Y-axis moving plate to which the X-axis moving plate is slidingly coupled for movement in the X direction, a fixed plate to which the Y-axis moving plate is slidingly coupled for movement in the Y direction, an X-axis driving system which uses a belt for moving the X-axis moving plate in the X direction, and Y-axis driving system which also uses a belt for moving the Y-axis moving plate in the Y direction. The X-axis moving plate and the Y-axis moving plate serve as the stage of the microscope. In operation, when it is desired to move the X- and Y-moving plates rapidly to generally position the object under the microscope, the belts of the X- and Y-driving systems are disengaged from drive elements associated therewith.

Abstract: A secondary image formation type view finder comprising an objective optical system, a first mirror for folding an optical axis, a relay lens system and a second mirror for folding the optical axis, wherein an optical axis of the relay lens system is disposed so as to be included in a plane nearly perpendicular to an optical axis of the objective optical system, and the first mirror and the second mirror and disposed nearly in parallel with each other, thereby reducing a space to be occupied by the view finder.

Abstract: A method and an apparatus for increasing detection signal-to-noise ratio, while reading out a hologram from a holographic storage medium, are disclosed. The hologram is written by interfering a write reference beam with an object beam. The method comprises the steps of (1) effecting multiple sequential hologram-read operations using multiple read reference beams separated from each other by a separation angle; (2) shifting the detector array contents in between hologram-read operations such that the data signal patterns incident on the detector array are approximately identical but the incident scatter noise patterns are uncorrelated; and (3) integrating the multiple hologram readouts electronically on the detector array. The apparatus comprises a laser source, a beamsteerer, a detector array and a shifting device.