A plurality of optical guide paths are built in a guide path plate. A plurality of optical guide posts are erected on the guide path plate so that each may oppose to one end of the corresponding optical guide path. The other end of at least one of the optical guide paths is optically connected to a light projecting portion, and the other end of at least another of the optical guide paths is optically connected to a light receiving portion. A part to-be-sensed which is movable is located between the distal ends of the optical guide posts whose base ends are connected to the corresponding optical guide paths. The presence of the part to-be-sensed is detected in such a way that the part to-be-sensed interrupts or transmits light which passes between the distal ends of the optical guide posts.

A system for detecting optically-sensitive properties of sheet materials during manufacture includes a first group of bundles of optical fibers that convey light to selected transmitting locations adjacent one face of the sheet material. The system further includes a second group of bundles of optical fibers that collect and convey light transmitted through the sheet material to a light detector. The light detector measures the intensity of light received from each of the bundles of the second group to provide measurements of optically-sensitive properties of the sheet material at selected cross-directional locations.

A light-transmissive device, illustratively a glass plate, is disposed adjacent to a plurality of light-emissive pixel locations, illustratively the pixel locations of a cathode ray tube (CRT). The glass plate entraps light originating from the CRT at least when an object, such as a document, is placed on one of the surfaces of the light-transmissive device, the amount of light that is entrapped being a function of the reflectivity characteristics of the document. The pixel locations are successively energized and a light detection signal indicative of the level of the entrapped light is generated by photodetection circuitry disposed adjacent to the edge of the glass plate. A pixel signal is stored for each energized pixel location, that signal being a function of the level of the light detection signal during the time that that pixel location was energized. The ensemble of stored pixel signals can then, for example, be displayed.

The invention relates to an apparatus for counting objects, which includes a light emitting system intended to form an emission zone, a light receiving system forming a plurality of substantially aligned reception points, a passage between the emission zone and the reception points to allow the conveying of objects to be counted substantially perpendicularly to the alignment of reception points, and a counting system provided to determine the number of conveyed objects as a function of the variations of light received at the reception points, which variations are due to the interpositioning of objects between the emission zone and the reception points. The receiver system includes a plurality of receivers intended to each form a reception point, while the emitter system includes as many individual emitters are there are receivers, and forms a plurality of substantially aligneed emission points; the emitters being provided to each emit a directive light beam and the receivers being associated by pairs with the emitters so that each receiver is provided to collect to receive, in the absence of an object, the light beam from the emitter with which it is associated and a consequently generate a signal.

An apparatus and method for computed radiography includes a rotating laser as a pumping source for delivering light, without the use of a rotating mirror, successively to ends of each of a plurality of optical fibers arranged in an arc. Opposite ends of the optical fibers are arranged in a linear array to a previously-exposed computed radiography plate having a latent X-ray image formed thereon. The plate is moved with respect to the fibers. Light emitted from the radiographic medium due to excitation by the pumping light travels through a light guide to an optical receiver where an image signal responsive to the light intensity of the emitted light is generated. The image signal is sent to a processor to generate an image representative of the latent X-ray. An erasing of the latent x-ray image may be accomplished in the same machine apparatus that generates the representative image. Preferably, multiple erasure operations are performed with a relaxation period, e.g., three to ten seconds between successive erasing operations. The laser is accurately positioned by an adjustment mechanism in an axial direction to focus the laser light on receiving optical fiber ends and in a radial direction to align the rotational axis substantially coaxially to the axis of the arc for the optical fibers. Electrical power is delivered through a brush and contact to leads in a rotating drive shaft for the rotating laser. The preferred light guide comprises an inlet positioned to receive phosphorescent light from the imaging plate and rearward and forward reflective surfaces for reflecting incoming light back and forth within the light guide that was not directly aligned for travel along a straight line path directly to the light collector, e.g., a photomultiplier tube. A substantial portion of this reflected light will eventually travel forwardly along a path of travel to hit the photomultiplier tube.