Abstract: In an exposure meter having a row of lighting elements, such as lamps or light-emitting diodes, which correspond to respective exposure values, an improvement is made in that by utilizing a capacitor-charging integrating circuit, a constant current circuit and a ring-counter, an exposure value between two neighboring steps of the above-mentioned exposure values can be indicated by lighting said two lighting elements, and in that ranges of exposure indication can be switched by shifting a dial plate, which is facing the lighting elements, in interlocking relation with a range-shifting switch for switching its circuit for range selection, thus enabling a doubling of the steps of exposure values to be indicated with a limited number of lighting elements.

Abstract: A panoramic rear viewing system for an automotive vehicle includes plural fiber optic bundles having input ends mounted behind lenses in swivel mounts at various positions around the periphery of the roof of the vehicle for viewing in adjoining rearward azimuthal sectors. The output ends of the fiber optic bundles are located in a side by side array behind a similar array of magnifying lenses within view of the driver for combining the sector images carried by the bundles into a panoramic view.

Abstract: An optical digital to analog converter having a plurality of input channels, each having the presence or absence of light representing the respective ones or zeros of a digital code, each of the input channels being coupled to a channel consisting of cascaded magneto-optical mode converters, the number of cascaded elements being equal to the corresponding weighting value of the element of the code, and a common receptor to which the outputs of the cascades are coupled.

Abstract: A fiber optic cable for use in a fiber optic connector has a transparent sleeve formed on the end of the fiber optic bundle of the cable. The end of the sleeve is closed and extends over the end surface of the bundle to form an optical window therefor and a protective spacer so that when two cables are mated in abutting relationship the end surfaces of the fiber bundles are spaced apart, preventing end surface bundle scratching which causes excessive light diffusion and results in light reception losses.

Abstract: A connector for connecting the opposing ends of a pair of light-transmitting cables, or the like, includes a slit sleeve externally tapered in opposite directions. A pair of tubular members are arranged to respectively fit over the opposite ends of the sleeve and are axially displaceable to force the sleeve radially inwardly into clamping engagement with a pair of cable terminals fitted in the sleeve. The cable terminals are held in close contact with each other, thereby to ensure easy, efficient, and axially aligned coupling of the cables.

Abstract: There is disclosed a technique whereby a dielectric grating disposed on a in film that has a surface wave propagating thereon can concentrate the power from this wave into a beam that is either above or below the grating according to the profile of the grating. By this technique, surface waves traveling in different directions can be distinguished and the efficiency of optical beam couplers can be improved, among other applications.

Abstract: In an optical fiber, light energy is transmitted in a number of modes having characteristic group velocities, and it is frequently necessary to limit transmission to modes whose group velocities are not excessively disparate. The invention avoids this limitation by providing a compensator (preferably) midway between two stations. The compensator pairs a fast mode in a fiber leading to one of the stations with a slow mode in a fiber leading to the other station, so that the group velocities for all pairs are approximately equal. The compensator comprises first, second and third focusing systems which are aligned with the fiber ends.The first system focuses energy received from one fiber into concentric rings whose radii are characteristic of the modes used in the fiber. The second system transposes, to a ring of maximum radius, energy focused at a ring of minimum radius, and vice versa.

Abstract: An optical transmission fiber which is formed by applying and baking a liquid resin composition or a solution or a dispersion prepared by dissolving or dispersing in a solvent a liquid or solid resin composition onto a glass fiber for optical transmission and, further, coating thereover by melt extrusion a thermoplastic resin composition.

Abstract: A mode transducer for use with a pair of optical wave guides for converting modes of different orders but of the same polarization to enable coupling between a first and second wave guide characterized by a coupling taper with a coupling structure arranged between the first and second wave guides with the coupling taper having an input thickness and a output thickness with the ratio of the opening angle of the mode at the input and the output of the taper being equal to the square of the ratio of the input and output thickness. In order to convert more than one mode for coupling between the first and second wave guides, the mode transducer may include a plurality of serially arranged tapers with each taper having a coupling structure and the wave guide receiving the coupled modes includes a segment of electro-optical material for each taper so that the phase of the coupled modes can be selectively changed to enable superimposition thereof.

Abstract: An improved radiation energy detecting system is disclosed. The system comprises a rotating scanning mirror reflecting energy radiating from objects in the field of view through a novel image derotating prism, providing optimum transmission modulation transfer and minimal dimension for packaging, and focusing optics onto a radiant energy detecting array. The detector converts the radiant energy to electrical signals representative of the impinging radiant energy for display processing.

Abstract: An optical waveguide coupler made by integrated optical circuit techniques is employed to direct light from a document to be copied to a line of photosensors of a large scale integrated photosensor module. A plurality of optical waveguides are spaced widely along the document and closely along the photosensor array. Spaced channels are formed in a higher refractive index glass layer on a glass substrate. The higher index layer glass provides the plurality of optical waveguides separated by the channels.

Abstract: This invention relates to an optical waveguide switch and directional coupler providing variable coupling between two optical fibers. The coupler is fabricated in semiconductive material such as GaAs or GaAlAs. A double heterostructure is used having a higher index of refraction middle layer. Optical fibers are inserted in channels in the semiconductive material. Varying the reverse bias across the heterostructure junctions located in the material between the channels electrically changes the refractive index of the material and alters the coupling between the fibers. The device is applicable to switching in optical communication systems.

Abstract: An optical dielectric waveguide comprises a track made of a low loss material disposed in the form of a helix. Information in the form of a modulated light can be transmitted along said track. Preferably said substance is silica.

Abstract: This light or optical conductor is formed as an integral structure, preferably by extrusion, of an optical material such as glass or transparent plastics material. A light conducting core is supported in an envelope by means of lands and ribs arranged and shaped in such a manner that the core and the lands as well as the ribs are surrounded by hollow spaces which are preferably filled with air. The ribs are tapering away from the core toward the envelope whereby light entering into these ribs through the lands from the core is reflected back into the core.

Abstract: A laser beam coupling arrangement for wide-band optical data switching systems, consisting of an electronically controllable, optical mask, a hologram, a waveguide matrix and a coherent light source employs dynamic hologram recording in which a sandwich structure is provided for hologram recording and comprises a transparent electrode, a photo-resistor layer, a dielectric reflector, electro-optical or electro-plastic material and a transparent counter-electrode between the controllable, optical mask and the inputs and outputs of the waveguides which are to be coupled.

Abstract: An optical wave guide comprises a cylindrical body which is made of a first transparent dielectric, and a second transparent dielectric which is concentrically formed on the outer periphery of the cylindrical body and which has an index of refraction lower than that of the first dielectric, the central part of the wave guide being hollow.

Abstract: An autoranging digital luxmeter is disclosed in which the current from a photocell is converted into a voltage by cascaded, variable gain amplifiers. The output of the amplifiers is coupled by a sample-and-hold circuit to an analogue-to-digital converter, the output of which is a digital representation of lux. The output of the amplifiers is also connected to limit comparison circuitry which, by way of an up-down counter, varies the gain of one or both of the amplifiers.

Abstract: A coupling device for coupling light waves between optical components for signal transmission including a developed, transparent, negative photoresist layer interposed between the optical components to be coupled.

Abstract: The disclosure is directed to optical fiber waveguiding structures, and techniques for fabricating the same, which are designed to have reduced modal dispersion as a result of the deliberate enhancement of mode coupling in the fibers. The mode coupling is achieved in each of the structures by means of an enveloping outer jacket, typically of plastic, which is selectively deformed so as to modify the straightness of the fiber axes in a spatially periodic manner. Several alternative techniques are presented for properly deforming the outer jacket either before or after it is combined with the fibers. Since, with these structures and techniques, the outer jacket provides the desired fiber perturbations, the fibers themselves can be fabricated using standard techniques without the need for any special procedures for modifying their parameters.

Abstract: A coupler for coupling optical energy transmitted by optical fibers to a thin-film optical waveguide and a method of manufacture. In the method an optical fiber is sandwiched between a pair of substrates and the substrates and fiber are bonded together with a suitable material. The bonded product is then cut to provide a surface including a cross section of the fiber. After polishing this surface a thin-film optical waveguide is then provided on the surface including the fiber end. The cutting angle is chosen such that, in the assembled coupler, the exit angle with respect to the waveguide surface is greater than the critical angle of the guide material. In this fashion the optical energy coupled from fiber to guide is trapped in the guide.The apparatus includes an optical fiber in a substrate with a cross section of the fiber in the surface of the substrate with a thin-film optical waveguide overlying the substrate surface.