Abstract: There is disclosed a fiber optic coupler for use in single strand fiber systems comprising a device to allow optical access to a single fiber by means of a second fiber which has been attached to it by fusing the glass cladding of the two fibers as by application of heat by a laser. The resulting access coupler provides for coupling both into and out of a single strand of fiber optic waveguide. That is to say, an input optical signal to one single fiber strand can be read out at more than one point on the single fiber or more than one input can be read out at a single point. The coupler is sufficiently low loss to make control systems utilizing single fiber lines rather than bundles a realistic possibility.

Abstract: A multi-hetero-structure waveguide type optical integrated circuit is provided wherein a thin-film element such as a semiconductor laser is coupled through a directional coupler to a waveguide having a small transmission loss.

Abstract: A method and apparatus for efficiently transmitting light through Cassegr type optics by way of fiber optics.

Abstract: A fingerpress is formed by pressing a finger against the back surface of a transparent glass plate and holding it in a predetermined position thereon. This fingerpress is interrogated by a light beam directed through the front surface of the glass plate. The interrogating beam is partially reflected at the back surface to provide a signal beam carrying fingerpress information. The signal beam is created by virtue of the optical discontinuity between the glass plate and the fingerpress. There is one discontinuity between the glass plate and the air underlying the valleys of the fingerpress and another discontinuity between the glass plate and the finger oil at the crests of the fingerpress. The two discontinuities cause differing amounts of light to be reflected and the signal beam is thus created. The signal beam is correlated against a hologram of the same fingerpress to provide identification. The hologram is created either from a film image of the fingerpress or from the fingerpress in real time.

Abstract: The body of a filter holder carrying a filter has a slot in which an engaging member is disposed for rotation between first and second positions in response to rotation of a shaft to which the engaging member is attached. In a first position of the shaft, retaining means on the engaging member is retracted within the slot for effecting insertion of the holder into a lens barrel. In a second position of the shaft, the retaining means projects from and is engageable with the lens barrel for retaining the body thereto.

Abstract: The invention concerns a connector for optical fibre telecommunication system. The fibres of each of the cables to be connected are held in channels formed between cylindrical holding rods clamped together, one of the sets of holding rods being surrounded by guide rods which extend towards the other set of holding rods so as to ensure the guiding of the latter at the time when the connection is made.

Abstract: A connector is disclosed for a fiber optic cable having one or more single optical fibers. A restraint member is fixedly attached to the strength member of the fiber optic cable. The restraint member is removably mounted in the rear section of a yoke while contacts terminated to the optical fibers are releasably mounted on the forward section of the yoke. The cable restraint member provides means so that the contacts may be positioned at equal distances from the end of the cable and the yoke permits the terminated fibers to be mounted in the connector without overstressing the fibers.

Abstract: The wave guide is constituted by a film layer C.sub.1 of magnetizable material having a constant refractive index n.sub.1 and placed between two media having refractive indices of lower value than the index n.sub.1. The layer C.sub.1 has two flat parallel surfaces which separate the layer C.sub.1 from the two media which have lower refractive indices and is constituted by a plurality of adjacent regions forming parallel layers, the gyrotropy of at least two of these regions being different.

Abstract: A thin chip having parallel, evenly spaced optical fiber-receiving grooves on at least one side forms the basic building block for a certain prior art multilayer optical fiber connector. The end arrays of fiber groups assembled within stacks of such chips are substantially identical in spacing, thus enabling a gang splice to be achieved with a simple abutment of the two end arrays. The present disclosure achieves vertical spacing between layers, as well as horizontal fiber spacing in a given layer, by including in the base of each chip a thin layer of compliant material to urge the fibers housed in the adjacent chip into their respective grooves. The compliance is sufficient to permit vertically adjacent chips to contact each other rather than to float atop fibers. The splice array additionally uses a key chip which rests upon a vertical reference surface with one end contacting a horizontal reference surface. These surfaces may form part of the permanent splice.

Abstract: This invention provides a connector for optical fibers which includes two connector sections each of which has a means for holding an optical fiber, one of the sections having an inclined surface engaged by the end portions of both of the fibers where their end faces abut. One of the fibers is bent to its position of engagement with the inclined surface as held in one section of the connector. The other of the optical fiber is bent by the inclined surface as the two connector sections are brought together to a mated position.

Abstract: A flexible tube filled with a liquid core material for transmitting, by total internal reflections within the tube, laser energy at relatively high power levels from a laser to a desired area of application. The tube and liquid materials are selected to be transparent to light at the wave length of output from the laser, and such that the tube material has a refractive index substantially lower than that of the liquid core material. Also disclosed are a number of liquid materials having highly desirable properties of low toxicity, color stability, low volatility, and compressibility. Various sealing means and input and output windows are disclosed for use at the ends of the tube.

Abstract: In a metering device for cameras comprising an operational amplifier, a photodiode connected between the positive and the negative input terminal of the operational amplifier, and a logarithmic conversion diode connected between the negative input terminal and the output terminal of the operational amplifier, the electric charge stored in the capacity present in the photodiode due to noise may be discharged to a capacitor which is adapted to reduce its potential in synchronism with the output potential drop of the operational amplifier.

Abstract: An exposure meter includes a plurality of indicating elements, such as illuminating diodes which are turned on by the output of a photometry device and the diodes are repeatedly turned on and off by the output signal from a switch. This turn on and turn off of the diodes can be reversely effected. By so doing, a preset shutter speed or stop value is indicated in the finder and pointer-follow function of the exposure can be achieved using the minimum number of diodes.

Abstract: A device for the transmission of light by optical conductors which are arranged in a plurality of bundles that extend between a display surface and a source of illumination and which are gathered together into a strand of conductors at either the display surface or source of illumination characterized by a coupling device, which may be separate or integral with the strand of gathered conductors, disposed at the strand to obtain substantially equal distribution of the intensity of light leaving the conductors.

Abstract: A fiber light conductor housed in a hollow tubular sheath with the conductor being given an undulating configuration in order to minimize the adverse influence thereon of mechanical stresses and external forces.

Abstract: The electro-optical switch according to the invention is formed by parts of two guides made of a ferro-electric material previously polarized in a suitable fashion, enclosed between two electrodes; the application of a voltage between the two electrodes has the effect of varying the refractive index of each of the guides in relation to the other and, consequently, of making it possible to enable or inhibit energy coupling between the two guides. Such a device is applicable in particular to integrated optical circuits.

Abstract: The present invention relates to the joining of a first glass member, such as an optical fiber, to a second member by means of solderable splices and terminations which additionally can form hermetic seals. To form the splice, termination or seal, the peripheral surface of the glass member is coated in the area of the intended joint between members with a thin adhering metallic layer. The coated glass member is properly positioned adjacent the second member and solder is flowed around the joint between the members. Where the second member is also formed of glass, a thin adhering metallic coating layer is similarly formed on the peripheral surface thereof in the area of the intended joint prior to solder being applied.

Abstract: Mode conversion of optical signals in thin film optical devices is obtained in a region of Faraday effect magnetic material waveguide by providing a periodic structure in which alternate half cycles have the magnetization parallel to the propagation direction to turn on the Faraday effect to induce mode conversion and in which the intervening half cycles have the magnetization perpendicular to the propagation direction to turn off the Faraday effect to prevent mode conversion. Stripe domains are preferably used to turn the Faraday effect off. Non-reciprocal mode conversion is obtained by optically coupling an anisotropic crystal to the waveguide to provide a quantity of mode conversion equal to that provided by the Faraday effect.

Abstract: A dielectric film layer C.sub.2 is deposited on a transparent film layer C.sub.1 in which two optical transverse TE and TM modes propagate and is provided with a metallic coating having reflecting properties on the face which is not in contact with the layer C.sub.1. The thickness of the layer C.sub.2 is such that phase-tuning is effected along the direction of propagation of the two TE and TM waves within the wave guide as essentially constituted by the layer C.sub.1.

Abstract: A device for coupling a light source, in particular a semiconductor laser, to an optical fiber in which the light source and the optical fiber are each connected to a cylindrical or part-cylindrical support and a coupling member is provided having two V-shaped grooves enclosing mutually a substantially right angle, in which the cylindrical supports, possibly carried by an additional member, after their mutual adjustment in the V-shaped grooves, are secured to the contact member. One of the supports may advantageously be provided in a V-shaped groove of a cylindrical or part-cylindrical auxiliary member which is secured in one of the V-shaped grooves of the coupling member.