Abstract: Methods for creating a plurality of holographic diffraction grating patterns in a raster scan fashion. In accordance with the method, the desired pattern is made up of a large plurality of individual spots, each spot comprising a holographic diffraction grating of a predetermined grating spacing and angular orientation for that spot. Variation of the angular orientation and/or grating spacing between spots and/or groups of spots provide the desired holographic effect. The spot locations may vary as desired, including locations drawing out a desired pattern, and two-dimensional orthogonal matrices in which a pattern is drawn by variations between spots or group of spots as in a raster scan type image. Various embodiments and methods for creating the same are disclosed.

Abstract: An optical equipment is equipped with a compact and high precision lens position detector which has a lens holder guide member which is made of a conductor and is provided with a detection electrode for detecting the position of the lens holder by a change in an electrical capacitance.

Abstract: A lens position definition apparatus is provided in, for example, a camera. The apparatus includes a base member, a cam mechanism for controlling a position of the lens relative to the base member along a direction of an optical axis thereof in accordance with a rotational position thereof about the optical axis, and at least one spring for urging the lens in a direction inclined to the direction of the optical axis and the rotation thereof, in order to enable the cam mechanism to operate.

Abstract: An optical head using a semiconductor laser array as a light source comprises a semiconductor laser array in which a plurality of semiconductor lasers are linearly arrayed, a collimator lens, an objective lens and a beam shaping prism system. The beam shaping prism system is arranged between the collimator lens and the objective lens to convert a beam width of a beam emerged from the collimator lens. The junction surfaces of the semiconductor lasers are parallel with an array direction. A plane defined by incident and emerging beams on and from the beam shaping prism system is parallel with or overlapping the array direction of the semiconductor lasers.

Abstract: This invention provides embodiments of etalons (10, 14, 18, 22) that eliminate or minimize a falloff of relative radiation modulation as a function of wavelength or FOV. A first embodiment employs a dispersive coating, such as a rugate (12a, 12b, 16), to correct for the phase shift across an etalon step. A second embodiment employs a dispersive coating, such as a rugate (20a, 20b, 24), that provides a stepless etalon in which the phase shifts are generated by the coating. It is shown that in a rugate the phase shift on reflection is directly related to the phase of a sinusoidal index of refraction profile within the rugate, while the frequency of the sinusoidal index of refraction profile determines the wavelength at which the phase shift occurs. By changing the phase of the sinusoidal index of refraction variation as the period of the sinusoidal index of refraction variation is changed, a phase shift of incident radiation is produced that is a function of the wavelength of the incident radiation.

Abstract: A rotary positioner is rotatably mounted upon a reciprocating carriage of a optical disk drive. To detect and indicate one of a plurality of possible orientations of the disk drive, a side bias force is applied to the rotary positioner in a direction orthogonal to the radius of the disk drive. It has been found that each orientation has a side bias at which gravity effects are removed from the rotary positioner. At these points of gravity accommodation, certain instabilities in servo operation occur. Since each orientation requires a different side bias force to create the respective servo instabilities, the side bias force causing such instability indicates the drive orientation. Two modes of testing for orientation are disclosed. The carriage positioner is actuate for causing a momentary uncorrected radial movement of the carriage. The response of the carriage servo is measured in one of two ways.

Abstract: A catadioptric reduction projection optical system is of a construction in which an on-axis light beam is used in a catadioptric system, and is designed such that resolving power is not deteriorated and a stop can be disposed.

Abstract: A zoom lens comprising, from front to rear, a first lens group of negative power, a second lens group of positive power and a third lens group of negative power, wherein as zooming from the wide-angle end to the telephoto end is performed by moving the first, second and third lens groups, the second and third lens groups both are directed forward and the speed of movement of the third lens group is faster than that of movement of the second lens group, the zoom lens satisfying the following conditions:1<S1w/S2w<3.20.15<.vertline.f3.vertline./FT<0.432<FT/FW<5where S1w and S2w are air separations between the first and second lens groups and between the second and third lens groups in the wide-angle end respectively, f3 is a focal length of the third lens group, and FW and FT are shortest and longest focal lengths of the entire lens system respectively.

Abstract: A re-imaging optical system (10) has a ref lective objective (12) providing an intermediate image of the object being viewed and a relay (14) including refractive (32, 62) and diffractive (34, 72) optical elements. The system is capable of re-imaging the intermediate image onto an image plane (16) with the characteristic advantages of reflective and refractive systems while eliminating their deficiencies.

Abstract: This invention concerns a fundus camera which can take photographs other than by fluorescence or by fluorescence. An optical device is withdrawn from the optical path of a photographic system at the same time as a barrier filter for taking photographs by fluorescence is inserted and is inserted in the optical path of the photographic system for observation purposes at the same time as the barrier filter is removed. The optical device has the same optical path length as the barrier filter, and thus a focused fundus image attained during observation is not upset when fluorescent photographs are taken.

Abstract: A zoom lens is disclosed which makes use of a space between an inner tube and an operating ring which does not impair operability of the zoom lens. Light guides are disposed in the space and illumination systems are incorporated in the zoom lens.

Abstract: A microscope adapted for use by two or more operators during surgical operations has a main objective lens and at least two mutually independent stereoscopic observation beam paths. Each stereoscopic observation beam path has a magnification system and a focusing system disposed therein. Pupil displacement systems are provided in modular construction of different mechanical lengths but of equal optical path lengths. This modular construction allows individual and customized configurations of the microscope for adaptation to meet the needs and requirements of various operating conditions and the various operating disciplines.

Abstract: A lens drive controlling apparatus includes a zooming lens, a focusing lens driven in follow-up relation to a movement of the zooming lens on the basis of a predetermined characteristic, a speed sensor for detecting a driving speed of the zooming lens, and a control circuit for determining a driving speed of the focusing lens on the basis of a detection result provided by the speed sensor.

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: A compact four-unit type of zoom lens system particularly suited for video cameras. The zoom lens system has a variable power ratio of about 6-8 and is made up of a reduced number of about 9-11 lenses. This zoom lens system comprises a first lens unit I having a positive refractive power, a second lens unit II having a negative refractive power, a third lens unit III having a positive refractive power and a fourth lens unit IV having a positive refractive power. The first and third lens units I and III are movable toward the object side for zooming from the wide angle end to the telephoto end while the second lens unit II remains fixed. The fourth lens unit IV is movable for correcting image position variations. The third lens unit III includes at least one positive lens element and one negative lens element with a concave surface facing the fourth lens unit IV. The fourth lens unit IV includes one positive lens element and may further include one negative lens element.

Abstract: A non-glass reflective surface is mounted near the top of the rear seat of a motor vehicle in such a way that the driver of the vehicle, by looking in the rear view mirror, can observe an infant in a safety seat wherein the infant is positioned facing the rear of the vehicle. This mirror is attached to the rear seat my means of a large safety pin and is further secured by means of strips of Velcro.

Abstract: The invention relates to a mirror for changing the geometrical form of a light beam. The mirror includes several mirroring regions with these regions being strip-like segments. An incoming light beam impinges on several of these segments which are all so aligned that the reflected component beams from all segments are imaged on one and the same component area of an axis. The mirror can be configured as one piece which imparts a linear beam geometry with only one reflection.

Abstract: A lens system containing an aspherical portion enabling minimization of spherical aberration as well as the lens length. The lens system includes a conical lens portion providing total internal reflection of light within the lens system and an integrally attached aspherical lens portion. For light rays within a defined angular range of less than about .+-.24.degree., the light rays are focused on the exit aperture (for a concentrator) at a minimum lens length, l.

Abstract: A scanner lens for reading has first to fourth lens groups sequentially arranged from an object side to an image side. The first to fourth lens groups are constructed by six lenses. Each of the six lenses is constructed by a positive or negative meniscus lens having a convex or concave face directed on the object side. The scanner lens further has a diaphragm arranged between the second and third lens groups. Refractive indices N.sub.g, N.sub.F, N.sub.d and N.sub.C at respective wavelengths on lines g, F, d and C, an Abbe's number .nu. on line d, and a partial dispersion ratio .theta.=(N.sub.g -N.sub.d)/(N.sub.F -N.sub.C) satisfy the following condition,(-0.0020793.multidot..nu.+1.3649)-.theta.>0.004. (1)with respect to one or both of third and fourth lenses adjacent to the diaphragm. A combined focal length f of an entire lens system and a focal length f.sub.1 of the first lens group satisfy the following condition,0.95<f.sub.1 /f<1.

Abstract: Holographic apparatus and methods are provided for generating high resolution telescopic images using low cost, small aperture lenses. Holographic media, such as photorefractive crystals, are used in conjunction with multiple and/or synthetic aperture techniques. In a multiple aperture system, a thin nonlinear holographic medium is used with a plurality of small optical lenses to compensate for the inherent piston and tilt errors of the lenses, thereby providing higher resolution. In another embodiment, synthetic aperture techniques are accomplished by illuminating a far field object with coherent light, deriving a reference beam from the coherent light, and changing the position of the reference beam in accordance with a computational formula. A hologram is formed from a sequence of image exposures in the holographic media, each made at different positions with respect to the image.