Abstract: This specification discloses a reflective optical circulator, which uses an optical reflective device to reflect an incident light beam from an optical port so that the reflected light beams further pass through all optical devices (i.e., all sorts of optical crystals) on the optical paths. With a proper reciprocal-non-reciprocal optical crystal combination, a particular linear polarization direction is generated to guide the reflected beams to the next optical port. The invention achieves the effect of repeatedly using crystals, lowering the number of crystals and the length of the optical circulator. On the other hand, all optical ports can be installed on the same side of the optical circulator, minimizing the device and making it easy to use.

Abstract: In a method of spectrochemical depth-profile analysis of heterogeneous materials, a first burst of ablation laser pulses in a first beam is directed at a sample to form an ablation crater. A second single pulse or burst of laser pulses in a second beam having a smaller width than said first beam is then directed at the bottom of the crater so as to create a plasma that emits radiation representative of a component in the sample without a significant contribution from the walls of the ablation crater. The intensity of radiation from the plasma is measured and the concentration of the selected component is determined from the intensity of the radiation. The depth at which the measurement is taken is then evaluated and the above steps repeated to determined the evolution of concentration of said selected component as a function of depth.

Abstract: An apparatus and method of chromatic dispersion includes the negative compensation per channel filter (130) coupled to an optical receiving path (100) for providing a lossless discontinuous per-channel dispersion compensation in the optical receiving path (100). The optical receiving path (100) includes an input port (131), at the input of the filter (130), for receiving an input optical pulse (120) having a packet of waves at corresponding frequencies transmitted and received by an optical fiber (115).

Abstract: Disk storage apparatus includes a loading and unloading mechanism for moving a recording disk from an insertion position to a reproduction position within the apparatus. When the disk is in the reproduction position, a locking mechanism is moved out of contact with an actuator which carries a read/write head so that the head can be moved across the surface of the disk by a motor mounted on the actuator. When an eject command is received, the actuator is moved to an inner crash stop and the disk is moved out of the reproduction position causing the locking mechanism to move into mechanical engagement with the actuator. A magnet carried on the locking means is moved adjacent a magnet within the motor so that the mechanical locking engagement is enhanced magnetically.

Abstract: The invention is an optical system cleaner for an optical disk drive in which a cleaning member is attached directly to a shutter or a member corresponding to the shutter to eliminate the need for a mechanism for linking the cleaning member with the shutter. An optical disk drive according to the present invention includes an actuator for projecting an optical beam through an optical system and to a desired position on an optical disk loaded at a reproduction position. The optical disk drive also includes a shutter opening means for opening the shutter of a cassette with a built-in optical disk. The body of the optical system cleaner has a substantially similar shape to said cassette and a moving member attached to the body of said optical system cleaner so as to move freely and driven by said shutter opening means. A cleaning member is attached to said moving member for sweeping out said optical system by merely taking the body of said optical system cleaner in or out of said optical disk drive.

Abstract: An apparatus for optically detecting light-absorbing contamination in at least one particle of low optical-loss material comprises an optical integrating chamber for containing the particles. A laser for emitting a laser beam to illuminate the particles is mounted in the plane of rotation of a rotating mirror such that the laser beam scans in a fan scan. A scanning assembly is mounted in optical alignment with the laser for reflecting the laser beam and for causing the laser beam to scan the particles in the optical integrating chamber. A focusing assembly is mounted in optical alignment with the laser for focusing the scanning laser beam onto the particles in the chamber, the focusing assembly operating in conjunction with the scanning assembly so that light from the laser beam is reflected from the particles and is repeatedly scattered onto the interior walls of the integrating chamber.

Abstract: An optical apparatus for sensing the motion of an object. A light source transmits light through a first and second optical fiber. The first and second optical fiber are positioned on opposite sides of a modulator or code disk to face each other along an optical path. The modulator has alternating reflective regions and transmissive regions which modulate the light propagating along the optical path as the modulator moves across the optical path. The modulated light is received by the first and second and optical fibers and transported to a predetermined location for evaluation.

Abstract: A structure providing a monolithic integration of an optical detector with an optical transmitter working in the region of the visible or the near IR spectrum. This source type makes it possible to transpose a perceived image belonging to a wavelength region to another wavelength region with a good output (photons/electrons coupling). Such a device may find particular application in imagery and signal processing systems.

Abstract: Laser scanning apparatus comprising stationary optical laser source apparatus for producing a scanning beam and a reference beam, beam delivery apparatus for delivering the scanning beam onto a surface to be scanned, beam position detector apparatus for measuring the position of the scanning beam by sensing the position of the reference beam and fiber optic apparatus for delivering the scanning beam and the reference beam from the optical laser source apparatus to the beam delivery apparatus.

Abstract: An encoder comprises a rotatable or longitudinally displaceable body having a plurality of sawtooth-shaped regions which lie one behind the other in the direction of rotation or displacement. Each sawtooth-shaped region is separated by a steep edge that extends transversely to the direction of rotation or displacement. Upon movement of the body due to its sawtooth-shaped configuration, the distance of the surface of the sawtooth-shaped regions changes relative to a distance sensor arrangement. An evaluation circuit receives the output signals of the sensor arrangement and determines the rotation angle or the displacement of the body. The sensor arrangement comprises two distance sensors being offset relative to one another in the direction of movement by less than one sawtooth-shaped region forming distance signals, with the distance signals input to the evaluation circuit. The evaluation circuit evaluates only one of the distance signals in order to determine the angle or displacement of the body.

Abstract: The invention provides an optical encoder for use with various density code wheels. The encoder provides a geometric offset for a photodetector that is fully illuminated. A circuit offset is provided for a photodetector that is not illuminated. The encoder comprises a light source; a principal photodetector; a pair of secondary photodetectors on opposite edges, respectively, of the principal photodetector; and a code wheel having plural alternating windows and spokes which respectively transmit or block light from the light source. The code wheel is mounted between the light source and the photodetector. The principal photodetector has a unit width and a first length. The secondary photodetectors each have a half-unit width and a second length; the second length is less than the first length.

Abstract: A focusing error detection apparatus for detecting a focusing error of a converging light beam on a surface of a recording medium in an image forming system.

Abstract: The detector is a charge transfer detection matrix and the measurement is effected by barycentric calculation. The stages of the method are as follows: Centering the measuring field (30) around the estimated position of the bright object (PI(1); selecting a first group of NS brightest pixels (31); selecting from these NS pixels the NA pixels clustered around the pixel having the maximum level (37); finally performing a barycentric calculation on the only clustered NA pixels (IE) of the measuring field.

Abstract: Method and apparatus for surveillance of a determined space in which a camera lens enables an image of said space to be formed on a set of photodetectors associated with information processing means, the set of photodetectors being a linear strip of photodetectors, for example, mounted so as to be fixed relative to the lens which is itself mounted to rotate about a transverse axis and which is displaceable by drive means to occupy predetermined angular positions about said axis.

Abstract: The device includes an objective (12) and a photosensitive detection matrix CCD (110) provided with a read register and an output stage. According to the invention, the device furthermore includes read means (13) for reading the matrix, in groups of 4 or 9 pixels arranged in a square, these groups being arranged in quincunx, and for determining the brightest square group.

Abstract: An apparatus for photo-optically detecting transducer motion using a photodetector resiliently suspended inside the transducer housing and photo-optically coupled to a light source. During movement the inertia effect of the photodetector along with the resilient suspension system causes the changes in the photo-optical coupling between the photodetector and the light source. The inertia effect of the photodetector is enhanced by adding a mass to the photodetector. Either the magnitude or the phase of the photodetector output is monitored to detect movement. In another embodiment, a light emitter is resiliently suspended so that movement induced changes in the position of the light emitter alter the coupling of light to one or more light detectors.

Abstract: A collimator/aperture, in an absolute encoder, produces a line of light to illuminate the encoder's code wheel. The collimator employs a bundle of fiber optics to receive an intense and generally cylindrical beam of laser light. The opposing end of the fibers are spread in a fan and clamped between carefully dimensioned clamping surfaces to produce a line of light one fiber thick. The collimator/aperture avoids the wasted energy associated with a slit mask. The fiber optics are held parallel near their light emitting ends and the ends are polished square to the axis of the fibers to provide a high degree of collimation. Fibers with low numerical aperture further improve the collimation.

Abstract: Disclosed is a disk for a revolution sensor including: a disk-like base plate having a circular hole formed in a central portion thereof and a plurality of detection holes formed in an outer peripheral portion thereof; and a resin portion integrally secured to an inner peripheral portion of the base plate and provided with a holding hole. The holding hole has a diameter smaller than that of the circular hole and is formed coaxially with the circular hole. A plurality of notched portions are formed circumferentially at equal intervals in the inner peripheral portion of the base plate, and are integrally engaged with the resin portion. Accordingly, the relative movement of the base plate and the resin portion is prevented, and the circularity of the holding hole and the coaxiality of the holding hole with respect to the circular hole are improved.

Abstract: A method of and apparatus for differentiated measurement of smoke and/or vapor in the outgoing air of a device, especially a microwave unit for disinfection and sterilization of goods includes the steps of deriving a signal commensurate with the presence of vapor in accordance with the intensity increase of refracted and/or reflected light, and deriving a signal commensurate with the presence of smoke in accordance with the pulsed intensity decrease of light passing through the outgoing air.

Abstract: The method of measuring the relative between submicron lithographic features on a wafer having thereon a reference characteristic associated with a reference submicron grating structure of periodicity p.sub.1 onto which there may be cast from a reticle the image of a projected submicron grating structure of different periodicity p.sub.2 comprising measuring the extent of change in a moire fringe pattern produced by the superposition of the two grating structures on the wafer.