Abstract: The present invention relates to an optical sensor of air borne acoustic waves. The sensor comprises means for producing mutually coherent optical sampling and reference beams, which may be combined to form an intermediate frequency carrier, the sampling beam being exposed to the acoustic field, in which acoustic wave induced density variations occur. These density variations produce a variation in the index of refraction and thereupon a phase modulation of the sampling beam. This phase modulation may be recovered by an optical detector and a phase detector as an electrical signal representative of the acoustic signal. The invention has application to security systems.

Abstract: A stereoscopic-vision endoscope of the present invention comprises a tubular elongated insertional part, an objective optical system situated in the insertional part, a relay optical system situated in the insertional part for transmitting an object image formed by the objective optical system, a pupil dividing stop for dividing a light beam emanating from an object image formed by the relay optical system into a plurality of portions, an image formation optical system for receiving light beams from the pupil dividing stop so as to form a plurality of object images having parallax, and imaging devices for picking up the object images formed by the image formation optical system. The relay optical system satisfies the condition .phi..sup.2 /L>0.43 (where .phi. denotes an outer diameter of a system of relay lenses, and L denotes a relay length of the relay optical system).

Abstract: In a non-flexible endoscope consisting of an insertion section and an eyepiece section which are separable from each other, an optical system configured so as to correct chromatic aberration produced by an observation optical system disposed in the insertion section with an eyepiece optical system disposed in the eyepiece section. The optical system according to the present invention selects a simple composition for the observation optical system so that it is manufacturable at a low cost and disposable, and is configured so as to have favorable optical performance as a whole by correcting chromatic aberration produced by the observation optical system with the eyepiece optical system.

Abstract: The line bow phenomenon is reduced by appropriately setting the reflective surface and/or the external shape of an optical element (e.g., a toric mirror) thereby realizing approximately linear illumination of the surface of the original document that is being read. In order to do this, optical elements can be formed so that the external shape of the reflective surface of the optical element is bow-shaped. Alternatively, the optical element can be arranged so that the optical axis of the reflective surface is parallel to the axis of the light reflected from the reflective surface.

Abstract: An array of M.times.N thin film actuated mirrors for use in an optical projection system comprises an active matrix, an array of M.times.N thin film actuating structures, each of the thin film actuating structures being provided with a first and a second actuating parts, each of the first and second actuating parts including at least a thin film layer of a motion-inducing material, a pair of electrodes, each of the electrodes being provided on top and bottom of the motion-inducing thin film layer, an array of M.times.N supporting members, each of the supporting members being used for holding each of the actuating structures in place by cantilevering each of the actuating structures and also for electrically connecting each of the actuating structures and the active matrix, and an array of M.times.

Abstract: A wide-angle side mirror device with a mirror box having a front and a rear, and first and second side walls. An object window is disposed in the first side wall of the mirror box. An observation window is disposed in the second wall of the mirror box. An object mirror having a curved shape which is concave in horizontal cross section and convex in vertical cross section is disposed to face out the object window and diagonally rearwards. An observation mirror is disposed in the mirror box to reflect a mirror image from the object mirror through the observation window. The object mirror preferably has a doughnut or drum shape, and more preferably has a degree of curvature in horizontal cross section approximately the same as a degree of curvature in vertical cross section. The observation mirror is preferably a flat mirror. The device has a wide field of view and allows the driver of a vehicle to view road conditions at acute angle intersections from the driver's seat.

Abstract: Improvement methods and apparatus for determination of optical properties of objects have been developed. The apparatus and methods of the invention provide an analog of color perception of human vision, preferably in the near infrared region, replacing spectrophotometers and narrow band sources used in other non-invasive near infrared detection methods. A plurality of detector units are used, each covering a broad and overlapping region of the detected spectrum, paralleling color perception and colorimetry. The improvements are primarily concerned with improving the signal-to-background (or noise) ratio such that the data stream is improved. These improvements use congruent sampling, comparison of different data streams from different sample portions or filter sets, using an interrogation system with sufficient speed to allow testing of arterial blood, and using a filter with a spectral structure. In some circumstances, a neural net is used for analysis, allowing the system to learn.

Abstract: Reflective polarizers, which transmit one polarization and reflect the other polarization, have an extended red band edge in the off-axis transmission spectrum to control off axis color (OAC) hue. To control the OAC hue, the red band edge of the off-axis transmission spectrum, or OAC spectrum, is shifted beyond the boundary for red light, or to at least 600 nm. Even more preferably, the OAC spectrum is extended further into the red than any red emission peak of an associated lamp providing light into a system in which the reflective polarizer is used. The concept applies equally well to any type of reflective polarizer, such as multilayer reflective polarizers, cholesteric reflective polarizers, and the like. The resulting reflective polarizers are very useful for many different applications, such as liquid crystal displays.

Abstract: A method is provided for greatly increasing the ratio of direct sunlight to earthshine in a sun sensor used on a spacecraft which is orbiting the earth and is used for the attitude determination of spacecraft with respect to the sun illuminated earth. The sun sensor is provided with a detector in which radiation applied thereto is restricted to a spectral region where the earth's atmosphere is extremely absorbent. Therefore, the detector only receives radiation in that spectral region directly from the sun, while any reflected light from the earth in the selected spectral region is absorbed by the earth's atmosphere, thereby never reaching the detector. One suitable spectral region is the ultraviolet absorption band from 200-290 nm and a UV enhanced silicon detector would be used in the sun sensor.

Abstract: A data acquisition circuit for a particle detection system that allows for time tagging of particles detected by the system. The particle detection system screens out background noise and discriminate between hits from scattered and unscattered particles. The detection system can also be adapted to detect a wide variety of particle types. The detection system utilizes a particle detection pixel array, each pixel containing a back-biased PIN diode, and a data acquisition pixel array. Each pixel in the particle detection pixel array is in electrical contact with a pixel in the data acquisition pixel array. In response to a particle hit, the affected PIN diodes generate a current, which is detected by the corresponding data acquisition pixels. This current is integrated to produce a voltage across a capacitor, the voltage being related to the amount of energy deposited in the pixel by the particle. The current is also used to trigger a read of the pixel hit by the particle.

Abstract: An optical coupling apparatus for a multimode infrared detector comprises a flux concentrator including a conical cavity, such as a Winston cone, having an entrance aperture for receiving infrared radiation and an exit aperture, and an integrating cavity in communication with the exit aperture of the conical cavity. A planar multimode antenna comprising a plurality of discrete antennas mounted on a silicon substrate is disposed within the integrating cavity so as to receive infrared radiation coupled into the integrating cavity through the exit aperture.

Abstract: An array of dual-band HgCdTe radiation detectors (10) wherein individual detectors include a first layer (14) having a first type of electrical conductivity and a bandgap selected for absorbing radiation within a first spectral band. The radiation detectors also each include a second layer (16) overlying the first layer. The second layer has a second type of electrical conductivity that is opposite the first type of electrical conductivity. Each radiation detector further includes a third layer (18) overlying the second layer, the third layer having the first type of electrical conductivity and a bandgap selected for absorbing radiation within a second spectral band. The first and second spectral bands are selected from SWIR, MWIR, LWIR, and VLWIR. The first, second and third layers are contained within at least one mesa structure (10a, 10b) that supports on a top surface thereof a first electrical contact (24) to the first layer and a second electrical contact (28) to the third layer.

Abstract: A method is disclosed for accurately providing general calibration of near-infrared quantitative analysis instruments for almost any individual user. The general calibration method comprises comparing an individual's near-infrared spectrum to a plurality of near-infrared spectral clusters. Each near-infrared spectral cluster has a set of calibration constants associated therewith. The calibration constants of the spectral cluster most closely associated with the individual spectra are used to custom calibrate the near-infrared analysis measurement instrument.

Abstract: For accurate position calculation of scintillation events in a gamma camera, photodetector signals are processed based on small groups of photodetectors surrounding the scintillations. Relative position correction and energy correction is carried out based on rough position values relative to the group of photodetectors, taking into consideration the number of the center photodetector and the sum of all photodetector signals in the group.

Abstract: A hand-held, battery operated, single photon sensitivity phytoluminometer is claimed for rapid, simple nondestructive, noninvasive evaluation of photosynthetic topography in green leaves. All the steps for generating phytoluminescence are performed within a single, light tight enclosure. The sensitivity of the instrument is such that stress induced changes in photosynthesis can be detected seconds after occurrence. Thus phytoluminography is made an easily applied technique for practical use by all those concerned with plant life.

Abstract: A method of measuring intensity of radiant energy fluoresced by a fluorescer in a radiation-cured coating. The method comprising the steps of: a) providing a coating comprising: i) a radiation-curable monomer or oligomer; and ii) a fluorescer having an excitation energy at a wavelength .lambda..sub.2, the fluorescer fluorescing radiant energy of a wavelength .lambda..sub.3 ; b) curing the coating by exposure to radiant energy, thereby changing the intensity of radiant energy that would be fluoresced by the fluorescer if exposed to wavelength .lambda..sub.2 ; c) illuminating the radiation-cured coating with excitation energy of a wavelength .lambda..sub.2, wherein at least 50% of the excitation energy is absorbed by the upper 75 .mu.m of the radiation-cured coating; and d) measuring the intensity of the radiant energy fluoresced by the fluorescer at wavelength .lambda..sub.3.

Abstract: Electromagnetic radiation detector and its production process. The detector comprises a thin detection material film (8), which is sensitive to the radiation to be detected and which has a first and a second faces (10, 12), the first face being directly exposed to the radiation to be detected, a resin coating (18) surrounding the thin detection material film (8) and having a lip (20) which projects beyond the first face (10) of the thin film (8).

Abstract: An improved near-infrared quantitative analysis instrument includes a number of removable finger inserts each dimensioned for a different finger size, which facilitates properly aligning and fitting an individual user's finger into the optical system of the analysis instrument taking into account the size of the individual's finger. The insert according to the present invention can be also designed to accommodate samples of various substances for quantitative analyte measurement.

Abstract: A method for evaluating a hydrocarbon so as to determine a desired parameter of the hydrocarbon includes the steps of providing a hydrocarbon to be evaluated, obtaining a near-infrared signal from the hydrocarbon, codifying the near-infrared signal so as to reduce the signal to a number of points, providing a neural network trained for correlating the number of points to the desired parameter and processing the number of points with the neural network so as to determine the desired parameter.

Abstract: A SPECT camera system has two detector heads (16a, 16b) which are movable between position (FIG. 2) and an adjacent, orthogonal position (FIG. 3). The detector heads have slide members (42a, 42b) which are slidably received on linear guide members (40a, 40b) of carriers (16a, 16b). The carriers have followers (20a, 22a, 24a; 20b, 22b, 24b) which are slidably received along linear guide paths (26a, 28a, 30a; 26b; 28b, 30b). Hydraulic or other extensible cylinders (32a, 32b) selectively permit the carriers, hence the detector heads, to slide along the guide paths between the 180.degree. opposite and the adjacent, orthogonal positions. Preferably, a rotating gantry (12) is rotated to place both detector heads above an intended position. In this manner, the extensible cylinders controllably lower the detector heads as they move by gravity from the present position to the intended position. In both the 180.degree.