Abstract: This invention relates to reading and analyzing the contents of sealed mail. The invention has utility in the sorting of sealed mail and in the matching of mail envelopes and its contents. The contents of sealed mail are read by having a light in the near infrared directed to the sealed envelope and creating an image of the printed matter on the contents by directing the light to an optical detector. The image thus received is analyzed and a determination can be made whether contents are of high value or whether the addresses on the envelope match the addresses of the contents. If the envelopes are not addressed, the address can be printed on the envelope after analysis of the address block of the contents.

Abstract: The invention relates to a high-precision autofocusing arrangement for a stereomicroscope wherein a bar-shaped marking is projected via a cylinder optic on an object. The imaged bar-shaped marking is at least in one dimension less or equal to the resolution of the viewing beam path. A region of the objective not used optically is selected for projection as the pass-through pupil.

Abstract: A filtering system is disclosed for receiving and bandpass filtering free space optical signals. The filtering system includes a plurality of optical fibers for accepting an optical signal. The fibers are implanted in an embedding material, having an index of refraction which is less than the optical fiber, for collimating the optical signal. The signal is further passed through a narrow, bandpass filter before detection by a photodetector device. In an alternative embodiment, the optical fibers are enclosed in a cladding, having a surface roughness at the interface of the cladding and the fiber, for enhancing the collimation of the optical signal.

Abstract: An image reading method and apparatus are capable of high-quality reading of a transparent original with an optimum light quantity by maintaining both a transmitting light source unit and a reading scanner at an adequate relative position to keep their optical axes in alignment during scan reading. Such alignment is achieved by providing synchronization in scanning speed by placing either one of the transmitting light source unit and the reading scanner at an arbitrary selected position, scanning the proximity of the selected position with the other, determining a light quantity distribution, determining a synchronous position from the distribution, carrying out such synchronous position detection at two or more distinct positions, and calculating the scanning speed ratio of the transmitting light source unit to the reading scanner from the result.

Abstract: A distance measuring device measures distance by optically measuring the length of a flexible member, such as a line, as it is left off a reel. The line is provided with a plurality of dye marks spaced at predetermined increments. The dye marks are detected by an optical sensor. The optical sensor is operatively connected to a circuit which maintains a count indicative of the length of the line. The count is displayed on an LED display.

Abstract: A modulated light beam obstacle detector for use as a safety mechanism in an automatic closure operator which must operate in varying ambient light conditions. If the obstacle detector senses the interruption of the light beam, the motion of the door is arrested or reversed. The obstacle detector uses an auxiliary light source connected in a feedback circuit to maintain a constant background illumination on the light detector and thereby hold the light detector in conduction at all times. In this manner, the presence of the light beam can be sensed regardless of the ambient light conditions.

Abstract: A system for differentiating magnetic recording media of varying shades of black comprises a controller 10, first and second amplifiers 12A, 12B, and first and second fiber optic cables 14A, 14B. The sensitivity of the first fiber optic unit is adjusted such that it detects gamma ferric oxide media but not metal particle or barium ferrite media. The sensitivity of the second unit is adjusted such that it detects both barium ferrite and gamma ferric oxide media, but not metal particle media. The controller employs binary logic to determine which type of media is being viewed by the fiber optic units.

Abstract: An optical sensor for monitoring position of a movable object comprising a LED and a phototransistor is provided with control circuitry, which is responsive to an output signal generated by the phototransistor for causing the LED to suspend radiation of light. When the light reflected from a reflective area of the object falls on the phototransistor, the control circuitry turns off the LED as soon as the output of the phototransistor goes below a threshold level signifying that the phototransistor has been turned on. When the light is absorbed by a non-reflective area of the object and the phototransistor is not turned on, the control circuitry turns off the LED after a predetermined time period, which is chosen to be slightly larger than the response time of the phototransistor.

Abstract: A direct conversion X-ray photo-electron cathode has specially designed secondary electron emission layers which provides high efficiency, low noise, high speed and broad band X-ray photon detection. The X-ray photocathode is integrated with a micro channel plate and an output phosphor display screen to form a panel type X-ray intensifier. The X-ray intensifier is combined with a micro-focus X-ray source to provide projection type X-ray microscope for use in X-ray microscopic diagnostic applications.

Abstract: A light emitting element array substrate includes a plurality of light emitting elements arranged in line on the substrate with less dispersion in irradiation to a surface to be irradiated and can be manufactured with a reduction of cost. The light emitting element array substrate also includes light reflecting members formed on the light emitting element array substrate about light emitting elements having less irradiation. The light reflecting members re-reflect the light emitted from the light emitting elements and also reflected by surrounding parts so that the quantity of light at portions of the light emitting element array substrate having less irradiation is complemented by the re-reflected light to level the entire irradiation in the light emitting element array substrate.

Abstract: The present invention is a method and apparatus for selectively altering the sensitivity of an optical sensor. The sensor has both a light source and a detector which are optically aligned with one another. The detector produces a first output signal level in response to light having an illumination intensity greater than or equal to a threshold intensity, and a second output signal level in response to light having an illumination intensity less than a threshold intensity. The sensor further includes the ability to selectively alter the illumination intensity of the light emitted by the light source to a lower level between the threshold intensity and the normal operating intensity. Hence, operating at the lower intensity enables the sensor to detect translucent sheets or facilitates identification of marginally operable sensors.

Abstract: A charge collection control circuit generates a time-varying voltage that is used to control the charge collection process in an MOS photodetector for the purpose of obtaining greater dynamic range. Control is exercised either by means of an integration control electrode that controls the flow of charge from a charge-collecting region to a sink or by means of a transfer electrode that controls the flow of charge from the charge-collecting region to a charge-transport region through which the collected charge flows to an output circuit.

Abstract: An optically isolated current mirror provides an isolated output signal as a function of an input signal. The mirror includes first and second optical isolators and an amplifier. The amplifier is connected to the first and second optical isolators in a voltage follower configuration which supplies the output signal as a function of an isolated control signal and an isolated feedback signal. The first optical isolator is connected between a source of the input signal and the amplifier. The first optical isolator includes a photosensitive np junction which generates the isolated control signal as a function of the input signal. The second optical isolator is connected to the amplifier in a feedback loop. The second optical isolator includes a photosensitive np junction which generates the isolated feedback signal as a function of the output signal.

Abstract: An optical detector having a detection surface and a mirror sized and positioned relative to the surface so as to receive and return light which is reflected off of the detecting surface within the response time of the system.

Abstract: A method of operation of a light curtain system for sensing the intrusion of objects into detection planes which define a protected zone. A group of light beams are strobed from one transmitter in a first direction across a zone to a receiver, and another group of light beams are strobed from another transmitter across the zone to another receiver. Light beams within each group which intersect a desired entry area are deactivated for penetration of a permitted object, and other beams in the groups are enabled to detect intrusion into the objects in portions of the zone which lie around the entry area.

Abstract: An optical latch circuit is used for an optical-input section in a processor chip having a plurality of processor units each of which includes a processing section and an optical-input section. The optical input section includes a two-dimensional array, or matrix, of optical latch circuits. The optical latch circuit comprises a photodiode, coupled to a differential amplifier circuit having two CMOS circuits and a latch switch; a PMOS transistor of one of the CMOS circuits receives a control voltage from an auto-zero negative feedback circuit to produced threshold values by itself; and a PMOS transistor of the other CMOS circuit receives a control voltage from an optical-input stabilizing circuit, complementary to the auto-zero negative feedback circuit. The optical input of the photodiode is latched and amplified by turning on and off the latch switch in synchronism with the control clock, for transmission of digital electrical signals to input gates in the processing section.

Abstract: A focus error signal detection device comprising an optical system for guiding a reflection beam reflected from an optical information recording medium to a photo-detection system side. A beam dividing system is arranged for dividing the reflection beam to two beams. Two photo-detecting units are arranged for detecting the two divided beams, respectively, each unit having light receiving surfaces arranged on a same plane. A beam position adjusting system is arranged for adjusting optical axes of the two divided beams with respect to predetermined positions of the photo-detecting units by simultaneously moving the two detecting units with respect to the beam dividing system.

Abstract: An optical sensor head for the directional detecting of optical radiation has an arrangement of individual optical systems that are differently sloped with their optical axes, are convergently aligned in the viewing direction and each have conical, partially overlapping viewing areas. To provide an exact bounding of the observation sector assigned to the sensor head without any impairment of the operatability, at least one outer-edge-side individual optical system of the sensor head is provided with a beam diaphragm which partially shades the assigned viewing cone. At least one of the neighboring optical systems, which is situated closer to a sensor center, is arranged with its light entrance opening approximately at the level of the diaphragm-bounded edge beams of the outer-edge-side individual optical system.

Abstract: An optical equipment comprises: a first lens for focusing and compensation for magnification variation; a second lens for magnification variation; position detection means for detecting positions of the first lens and the second lens; focus detection means for detecting a focus status; lens drive means for driving the first lens and the second lens; and control means for controlling the lens drive means in accordance with information from the position detection means and the focus detection means. The control means determines a drive range of the first lens in which a circle of confusion may be zero, in accordance with focal length information, and inhibits the first lens from being driven out of the range during the magnification variation of the second lens.

Abstract: A method and apparatus for sensing electric and electromagnetic fields incorporating a fiber-optic transducer which mounts directly on a conventional optical fiber waveguide. The transducer employs a conductive Fabry-Perot microcavity bounded by a conductive, thin and corrugated diaphragm. When the conductive microcavity is placed in an electric field, the electric field is excluded from within the equipotential microcavity and a net electrostatic force acts on the diaphragm. Likewise, when the conductive microcavity is exposed to an electromagnetic wave, the wave exerts a radiation pressure on the diaphragm. In both cases, the diaphragm deflects linearly and uniformly under the influence of the extremely low electrostatic pressures which are induced. The diaphragm deflection modulates the reflectance within the optical fiber by varying the gap of the cavity.