Abstract: An optical range finder comprising first and second light emitting sources, and first and second light receiving sources, the light emitting and receiving sources being so arranged as to form four optical paths between the first light emitting source and the first light receiving source, the first light emitting source and the second light receiving source, the second light emitting source and the first light receiving source, and the second light emitting source and the second light receiving source, at least one of the optical paths being a distance measuring optical path passing an object, the other optical paths being reference optical paths.

Abstract: A variable attenuator for optical transceivers such as laser rangefinders for ordnance control. A polarization rotation device, such as a mechanically rotatable half-wave plate or an electrooptic cell, operates in combination with a beam splitter polarizer to attenuate the transmitted laser beam by a continuously variable amount without further attenuating the received laser beam.

Abstract: Apparatus and method for reducing the cost and complexity of equipment placed on subscribers' premises in a subscription communications system, such as a cable television system, while at the same time providing security against unauthorized system access includes a microprocessor controlled frequency converter in proximity to the subscriber's premises to convert information transmission signals to subscriber-receivable frequencies; a channel selection unit at the subscriber's premises for producing a command signal to initiate the transmission of information to the subscriber; and a verification circuit coupled to receive the command signals, to verify the same and electronically to instruct the microprocessor. The microprocessor may be provided with plural, plug-in converter modules for feeding signals to several subscribers and may be made responsive to subscriber generated auxiliary function signals from alarm detector units, utility meter reading devices, and the like.

Abstract: The disclosed apparatus determines optically whether an object is located within a first range of distances from the apparatus or a second range of distances from the apparatus. A radiation projecting arrangement projects a beam towards the object and a receiving arrangement disposed a predetermined distance transverse to the object direction receives the radiation reflected from the object. A pair of radiation sensors in the receiving arrangement each produce an electrical output corresponding to the received radiation. A circuit responds to the outputs of the sensors to determine whether the object is located within a first range or a second range. The circuit arrangement connects the radiation sensors so as to subtract their outputs, and one of the sensors is provided with a more extensive radiation receiving area than the other. This extends one of the range of distances.

Abstract: The invention relates to a method and apparatus for measuring the velocity of a moving object. Measuring beams composed of sequences of optical pulses are directed towards the object which is to be measured and follow such object. Based upon transit time measurements of reflected pulses there are formed distance values and distance difference values. While taking into account the time interval of the pulse sequence there are computed velocity measuring values and velocity values computed from homogeneous groups of values are displayed as reliable velocity values.

Abstract: A rangefinder device includes means for projecting a beam of light to illuminate a spot on an object in a scene. A linear image sensor views the scene and produces a series of photosignals representing the brightness of the scene. Signal processing electronics responsive to the photosignals from the linear image sensor detect the location of the illuminated spot in the scene and produce a distance signal representing the distance to the object. The signal processing electronics include:a counter that is advanced each time a photosignal is received from the image sensor;a latch connected to the counter and responsive to a control signal for temporarily storing the current count of the counter; anda peak detector responsive to the photosignals for producing an output signal each time a new greater photosignal is received.The output signal of the peak detector is supplied to the latch as the control signal.

Abstract: A distance measuring apparatus for automatically measuring the distance from a reference point to a subject of interest, such as a subject to be photographed, is provided. The present apparatus includes a position sensitive detector, a differential circuit and a pair of detecting/extracting circuits each connected between the detector and the differential circuit, whereby each of the detecting/extracting circuits includes electronic switches which change the mode of operation of the apparatus.

Abstract: The point of focus of an image is swept through a measurement zone in the image space of a lens system by sweeping a plurality of convex specular surfaces through the object space of the lens system to vary the object space. The specular surfaces are formed to approximate involute curves and the optical axis of the lens system is centered upon tangents to a generating circle of the involute curves which are approximated by the specular surfaces. The specular surfaces are mounted in a rotating member and sweep the object space by rotation of the rotating member about the center of the involute generating circle. An object of the lens system includes a light emitter and a light detector positioned adjacent to one another. As the measurement zone is swept, a minimum of the output signal from the light detector occurs when the image is momentarily in focus upon the surface of a workpiece within the measurement zone.

Abstract: An information signal (INF) which is transmitted in coded form (CINF) from a signal source (RC) to a signal receiver (4,5) is decoded at the receiver and at the same time marked (MINF) by the introduction of an identification information (ID) which is characteristic of the receiver or its possessor. The signal from a video disc (RC) carrying a coded programme is decoded and marked before it is supplied to a television set (6). Via said identification information a so-called pirate copy is directly traceable to its originator. Thereby a protection against such copying is obtained. A device for the playback of a video disc of this type comprises a decoding and modification unit to which the necessary decoding information and identification information may be supplied from a personal data carrier (ID).

Abstract: A subscription television system and method in which billing information regarding programs actually viewed by a subscriber of the system is accumulated over non-dedicated telephone lines. A scrambled television program signal containing a block of television program material, a program identification code unique to the block of program material, and a program category code, is broadcast. The codes are preferably included in the vertical retrace interval of the video portion of the program signal and the transmitted program signal is selectively received at a subscriber station and selectively unscrambled to permit viewing of the block of program material being transmitted in response to subscriber action indicating acceptance for viewing of the block of program material. The received program category code is compared with a locally generated category code to determine whether the program is acceptable for viewing.

Abstract: Apparatus for encoding and decoding information. Multiple scrambling techniques are provided to prevent unauthorized reception of a television picture signal. A first mode of scrambling provides for shifting randomly occurring horizontal synchronization pulses within each field of video signal producing horizontal as well as vertical instability. Video line inversion of selected lines within a field comprises a second mode of scrambling of the signal. A third mode of scrambling provides for amplitude shifting the television signal during selected portions of the signal which contains luminance and chrominance information following a line synchronization pulse.

Abstract: An improved method, and apparatus for performing the method, is disclosed for measuring and correcting the individual toe of pairs of steerable and non-steerable wheels of a vehicle relative to a longitudinal centerline passing through the midpoints of the wheel pairs. The improved methods utilize aimable alignment heads which are alternately mounted on the non-steerable wheels and the steerable wheels and are sighted only once on targets on the other wheels thereby eliminating the need for resighting after each toe adjustment is made. Optical cross-toe paths of each head operate in a continuous mode and provide a running display of incremental toe angle adjustments of one wheel while the toe display value associated with the other wheel of the pair is frozen, which other wheel is not being adjusted for toe.

Abstract: A distance measuring device comprised of a system which projects infrared rays on a distant object, a light receiving optical system positioned at a prescribed base length from the infrared ray projecting system; a sensor of the signal storage type including an array of light sensitive elements arranged in a position which approximately coincides with the imaging plane of the light receiving optical system. A control means arranged to cause the sensor to perform a storing action under a first condition in which the infrared ray projecting system is allowed to operate and also under a second condition in which the infrared ray projection system is not allowed to operate, and digital computing means designed to detect a difference between output signals of every light sensitive element respectively produced under the first and second conditions and to detect a distance to the distant object on the basis of the results of detection of the difference between these signals.

Abstract: Sync suppressed television signals transmitted with timing pulses in dynamically variable time delayed relationship with respect to the suppressed sync pulses are descrambled with a high degree of noise immunity by decoding tag pulses transmitted with the timing pulses into a digital signal representing the dynamically variable time delay relationship in terms of the number of such tag pulses during a predetermined period of time during each field of the TV signal, into a digital signal. The decoding is carried out to provide the digital signal with different values for different groups, each containing a different number of tag pulses. The pulses which restore the sync pulses in the TV signal in each field are timed with respect to the timing pulses in accordance with the value of the digital signal.

Abstract: An apparatus measures the distance of a target by measuring the time of travel of a light pulse from the measuring apparatus to the target and back wherein it is important to achieve high accuracy in timing to correlate, for a distant target, the time of transmission with the start of measuring the time of travel and the time of receiving a reflected light pulse and the end of the time measurement. For a near target, the start of distance measurement is correlated with receipt of a reflected measuring light pulse and a stop signal is correlated with a delayed reference light pulse. For this purpose a reference light pulse is branched off from a measuring light pulse and passed by light guides to a single receiver unit. The reference light pulse is passed to the receiver unit either through a short or a long light path depending on whether the target is distant or near, respectively.

Abstract: In order to control subscriber access to selected television programs in a CATV system, nonstandard horizontal synchronizing pulses, having a greater amplitude and either a higher or lower pulse repetition rate than the contained horizontal synchronizing pulses, are selectively added to those television programs to be controlled. As a result, the television receiver of a nonpaying subscriber interprets the nonstandard pulses as being valid horizontal synchronizing pulses thereby preventing the receiver from synchronizing its line scanning with that of the television program rendering the picture produced therefrom unviewable.

Abstract: A rangefinder device includes means for projecting a beam of light to illuminate a spot on an object in a scene, an image sensor having an array of photosensors for sensing an image of the scene, and signal processing means responsive to the photosignals from the photosensors for determining the relative location of the illuminated spot in the scene. The device includes an improved image sensor comprising an array of N photosensors for sensing the image of the scene and generating N photosignals in response thereto, and an analog shift register having 2N cells for receiving the photosignals, in parallel, into N alternate cells. The sensor is operated once with the light beam off and the photosignals generated thereby, representing the background illumination, are entered into the N alternate cells of the shift register. Then the contents of the shift register are shifted by one cell.

Abstract: A system of ocean depth sounding from the air which consists in projecting an infrared beam (2) down normal to the ocean surface along a forward travel path to backscatter a signal to a receiver (10) to measure distance to the ocean surface, and simultaneously projecting down a green beam (1) to sweep across the direction of travel to backscatter a series of signals from the ocean bottom over an extended width to a second receiver (11), adjusting the receiver gain from the green signal to achieve optimum ocean bottom measurement and calculating ocean depth from the infrared and green signal differential.

Abstract: The disclosed apparatus is a temperature tracking narrow band optical range finder which includes a prior art GaAs laser diode for emitting a laser energy pulse to a target and an improved GaAs avalanche detector for receiving a reflected pulse from the target. This range finder can be arranged in a single optical axis with the laser diode electrically shielded from the detector and the reflected pulse defocused so as to impinge on the detector area surrounding the laser diode, or it can be arranged by combining the emitted and reflected pulse in an interspersed fiber optical plane.

Abstract: A distance measurement system for measuring distance to an object by emitting light to the object and measuring the intensity of light reflected from the object.