Abstract: A method of controlling pressure in a wellbore can include placing a barrier substance in the wellbore while a fluid is present in the wellbore, and flowing another fluid into the wellbore while the first fluid and the barrier substance are in the wellbore. The first and second fluids may have different densities. Another method can include circulating a fluid through a tubular string and an annulus formed between the tubular string and the wellbore, then partially withdrawing the tubular string from the wellbore, then placing a barrier substance in the wellbore, then partially withdrawing the tubular string from the wellbore and then flowing another fluid into the wellbore. A well system can include at least two fluids in a wellbore, the fluids having different densities, and a barrier substance separating the fluids.

Abstract: An aperture correction system employing a tapped delay line includes an integral detection/gating circuit, whereby the combination generates an improved video detail signal by removing the objectionable noise and low amplitude components which are emphasized during the aperture correction process, while retaining the original shape of the high frequency video detail transitions as enhanced by the aperture correction process. The objectionable noise cancellation is provided by selectively gating the aperture correction signal via the detection/gating circuit in response to a selected gating waveform provided from the video detail signal itself. The detection/gating circuit may be selectively disabled to cause severe attenuation of the waveform at selected low and high frequencies outside the passband of the system.

Abstract: A digital dissolver dissolves between two different video signals in synchronism with a composite sync signal. Frame pulses are separated from the composite sync signal and are used to generate a high frequency signal in phase locked relation with the frame pulses. The high frequency signal is fed to a programmable frequency divider under the control of gating and control circuitry to provide an output pulse in response to each occurrence of a selected number of cycles of the high frequency signal, the selected number being a function of the selected dissolve rate programmed into the divider by thumbwheel switches or by signals from a remote location. The pulses are fed to a binary counter which feeds a digital to analog converter to generate a dissolve signal of generally ramp-like waveform. The dissolve signal and its complement are applied to a pair of multipliers to attenuate the two different video signals.

Abstract: A color television camera has a camera tube for receiving incident light from an image pickup object. It produces output signals representing an image of the object. The signal level varies in accordance with the incident light quantity assuming a constant target voltage. The system disposes of excessive incident light quantity. A control circuit lowers the voltage impressed on the target of the camera tube and controls the output signal level of the camera tube at a constant value, when the incident light quantity to the camera tube becomes excessive and exceeds a first predetermined light quantity. An indicator indicates when the incident light quantity to the camera tube becomes excessive, exceeding a second predetermined light quantity which is greater than the first predetermined light quantity. The resulting pickup picture deteriorates when the light exceeds a practical allowable limit despite the operation of the control circuit.

Abstract: A programmable image processor compares successive vertical frames of the received video image of an object placed within a television camera field of view with a similar object video image stored in memory, and provides a signal manifestation of the video mismatches therebetween. The programmable image processor provides for the scanning of the received video image by the stored video image in one, or both, of two orthogonal directions within the camera field of view, to distinguish between video mismatches resulting from dissimilarities in the video images and mismatches resulting from the misalignment of the object in one, or both of the orthogonal directions within the camera field of view.

Abstract: Apparatus for stabilizing the range of black to white level in a signal to a cathode ray tube, especially a signal produced by a detector in a charged particle microscope system. The stabilizing apparatus includes electronic circuitry for remembering the most negative (blackest) excursion of the signal for a predetermined time period, means for stabilizing all video input to that level and means for controlling the range of the signal (black to white) to remain within predetermined limits.

Abstract: An apparatus for use in conjunction with a processing system of the type which receives an input video signal comprising successive scanlines, each of which consists of a blanking portion that includes timing signals followed by an active portion representative of color picture information. The processing system is of a type that has an inherent delay whereby the output thereof is a television video signal delayed with respect to the input video signal. The invention is directed to an apparatus for generating a revised output video signal having timing signals in synchronism with the input video. In accordance with the invention there is provided a means for generating blanking portions in synchronism with the blanking portions of the input video signal.

Abstract: The smearing of moving images due to photoconductive and capacitive lags inherent to the photoelectric conversion target of a television camera can be removed by reducing the scan area of the target so that the electron beam traverses the target at a lower speed than the speed at which the corresponding portion of the image is traversed by the beam when the entire area of the target is scanned.

Abstract: A flying spot scanner is disclosed for scanning an object document or scene with a spot of light, and producing an electrical video signal representing the object. The scanner can be operated under normal ambient light conditions without a light-shielding enclosure. A light beam is deflected in repetitive scanning fashion over the object. The light beam is modulated in amplitude (intensity) at a radio frequency f.sub.c such as 1.2 MHz. A photodetector is positioned to receive light from the object, and it produces an unwanted electrical ambient light noise signal having a maximum frequency f.sub.a, and an electrical information signal consisting of a carrier at frequency f.sub.c modulated by a video signal having a maximum frequency f.sub.m, where f.sub.c - f.sub.m is larger than f.sub.a. The information signal is separated from the ambient light noise signal by a filter, and the information signal is demodulated to produce a facsimile or video information signal free of noise due to ambient light.

Abstract: A target for ultrasonic camera comprising, applied to a substrate, a pyroelectric retina covered, in the present example, with a layer which absorbs incident ultrasonic waves; the temperature rise due to said absorption produces in the retina a charge relief read out by means which depend upon the selected device, for example an electron beam as in the case of the known pyroelectric targets.

Abstract: The specification discloses a multiplexing system for an image detection array having laterally staggered first and second rows of image detectors which generate electrical signals representative of sensed images. First and second charge coupled device shift registers are connected to receive the electrical signals through channel inlets spaced along the lengths of the registers. Circuitry is operable during a first clock period for parallel loading electrical signals from the first row of detectors into a first set of alternate ones of the channel inlets of the first shift register. Circuitry is operable during a second clock period for parallel loading electrical signals from the second row of detectors into a second set of alternate ones of the channel inlets of the first shift register for storage between electrical signals from the first row of detectors.

Abstract: An improvement in methods of image analysis is described whereby the time required for analyzing certain types of images can be substantially reduced. The invention utilizes the light integration characteristic of a television camera to combine a succession of images applied thereto into a single composite image. A video signal of the composite image is then obtained by scanning in the usual way. Analysis of the video signal is performed in a known manner after threshold detection.The invention is of application to the analysis of microscopic specimens which are generally black or dark grey and which include a few widely spaced white or light grey features, on which the analysis is to be performed.One embodiment utilizes a single scanner and switching devices for alternately producing scanning and not scanning.

Abstract: In a telecine system using a flying spot tube, the latter is used for scanning, at the same time as the film, marker zones delivering, upon being scanned, marker signals characteristic of the vertical position of the horizontal line on which they are located. The marker signals are converted into electrical signals for comparison with a reference signal; the resultant output signal is used for correcting the vertical deflection of the flying spot. The marker zones may be scanned either by an image of the flying spot distinct from that which scan the film, or by the same image.

Abstract: An electronic camera with a vidicon tube, comprising a synchronization generator consisting of a frequency divider receiving the frequency of a quartz oscillator (Q.sub.1) and supplying, by combination, the various synchronization signals, in which the synchronization generator piloted by the quartz oscillator (Q.sub.1) consists of a first stage comprising the quartz oscillator (Q.sub.1) energizing two gates (NAND 1,2), to provide an output frequency successively divided by dividing circuits (CI.sub.1, 2, 3, 4), furnishing the respective signals to a combining stage M, combining the various signs (S.sub.1 -S.sub.5), and supplying the synchronization and scanning signals, the protection signals, the mixer signals and if necessary the reference signal of the high frequency generator (15).

Abstract: A low light level image pick-up tube is protected from excessive illumination intensity damage by controlling a very high voltage assembly supplying the tube. The tube comprises in a preferred embodiment a plurality of image intensifier stages in cascade preceding an electron gun from which a video signal is provided by electronic scanning.A mean level video regulation circuit provides from the video signal an output signal used for controlling the supply voltage value to at least one of the image intensifier stages including the last one i.e. that preceding the electron gun. Further, a signal proportional to the supply current to the last image intensifier stage is used for controlling the supply voltage value of the input image intensifier stage which receives focussed radiation from an observed field.

Abstract: An automatic focusing apparatus for use in a photographic or television camera having a lens system movable in predetermined incremental displacements in relation to a subject to be photographed in search of the true focus setting. A scanner is provided for scanning the image of the subject and for generating a serial video signal indicative of the image of the subject. This serial video signal is processed by maximum and minimum value detectors which generate signals indicative of the maximum and minimum values of the serial video signal to an extreme value detector through a difference detector. Output from the extreme value detector indicates that the image of the subject is focused in the image plane.

Abstract: 1. In a signaling system, a plurality of input circuits carrying signal currents, a corresponding plurality of individual output channels, a privacy equipment common to said circuits and channels for rendering said signal currents unintelligible, a first set of relays for operatively associating said input circuits one at a time with said privacy equipment, a second set of relays for operatively associating said privacy equipment with said channels one at a time, and a common timing circuit for operating the relays of each set in timed sequence.

Abstract: For reproduction on a television receiver, movie film is moved continuously past a scanning region. Each image is scanned three times in direction opposite to film motion, the starting point of each scan being displaced one-third of image height in direction of motion of film.

Abstract: Disclosed is a system for determining the contour of a plane form in which system the plane form is exposed to an industrial television camera; the video signal from the camera is converted into a train of binary signals "1" or "0", depending on whether a sampling point is bright or dark on the photo-electric converting plane of the camera; and the contour of the plane form is determined from the incremental length of the camera movement relative to the plane form or from the amount of the phase-shift of the sampling pulse required for causing the inversion of binary signals at the sampling points close to the contour of the plane form.

Abstract: Articles such as glass jars filled with food products are inspected for defects by scanning an x-ray image to provide video signals which are processed in a novel manner to provide increased sensitivity to detect very small foreign particles without decreasing a tolerance for normal variations, to inspect substantially the entire contents of a container such as a jar even if it has a varying diameter, without the need for precise positioning of the articles within an inspection zone, and without a need for an x-ray or optical mask tailored to fit each type of jar to be inspected.

Abstract: An optical system for a television camera provided with a device for emitting bias-light which is directed to the image pickup tube. Rays of light coming from a light source and entering a light guide plate at a side edge thereof are guided through the interior of the plate toward the opposite side edge after a number of successive total internal reflections from the two boundary surfaces of the plate. The surface of the plate near to the image pickup tube is provided with a diffraction grating formed therein to diffract a fraction of the light rays entering the plate, and to direct it toward the image pickup tube, thereby the image pickup tube is illuminated by the diffracted rays of light.

Abstract: Errors in the raster of a flying spot scanner are measured by placing a semi-reflecting surface in the path of the light to the object being scanned to form a secondary raster image in a position where such measurements can be made without interfering with the primary scanning operation. Preferably a feed-back circuit is used to control the cathode ray tube in dependence upon the measurement.

Abstract: A method of and apparatus for reading out information disposed as a surface deformation such as a thermoplastic deformation pattern is disclosed in accordance with the teachings of the present invention. A coherent light beam is projected to the surface deformation pattern and one of the first order components of the diffraction pattern received from the deformation pattern is imaged onto a surface. At the surface, the first order component is mixed with a further coherent light beam to form an interference pattern comprised of image modulated sinusoidal interference fringes. The interference pattern has an intensity that varies as a linear function of the amplitude of the deformation pattern. In a preferred embodiment thereof, the first order component of the diffraction pattern is imaged to the surface by an imaging lens optically positioned out of optical communication with the zero order component of the diffraction pattern.

Abstract: Optical diodes are shown in the forms of a mechanically contacted cat whisker system and as single and multiple microscopic solid portions in an integrated solid mass, defining both the antenna and the junction, preferably as a deposit of solid layers upon a substrate, preferably as overlapping printed circuit line structures. Arrays of such junctions provide enhanced effects.In a scanner, read-out from the junctions is shown indirectly, using an electron beam, and directly using leads connected to respective antennae. Local oscillators directing radiation upon an image disecting array, mixing in the junctions with incident radiation from the image create superheterodyne beats leading to improved levels of detection. By phase locking the local oscillator to the frequency of coherent image - illuminating radiation, and detecting phase of the beats relative to the illuminating radiation, as well as amplitude, a holographic display of the image is achieved.

Abstract: A circuit for improving the accuracy of a video measuring device which removes errors caused by variations in the horizontal deflection voltage by continuously monitoring the horizontal deflection voltage and comparing it with a preset reference voltage and adjusting the horizontal deflection voltage if any variation from the reference occurs. This assures that measurements made with the video system remain accurate at all times and measurements can be made with great accuracy.

Abstract: A method for enhancing the visibility on a television screen of small difficult-to-see game objects that are thrown or shot according to the rules of the game. The method comprises photographing the game while the game object that is being used in the game carries a retroreflective layer attached to the exterior surface of the object; and projecting a light beam parallel to the optical axis of said television camera so that light retroreflected by said retroreflective layer causes a visible contrast between the image of the game object and the image of the background for the object in a telecast picture.

Abstract: A cinematographic film to be reproduced by television is driven at constant speed in synchronism with the sweep cycle of one or more camera tubes each positioned to pick up images projected upon a receiving surface thereof whose luminous persistence equals at least a sweep cycle. The film is periodically transluminated, during the retrace phase of the scanning beam, by a light pulse emitted by an electroluminescent diode -- or by a cluster of such diodes operating on different wavelengths -- defining a quasi-pinpoint light source, the diode being excited by an energizing pulse whose length does not exceed the duration of a line scan of the camera tube.

Abstract: Superimposed pictures on the video outputs of cameras resulting from picking up stray transmitted television signals are eliminated by shielding the camera amplifier, and by insertion of inductances at the input of the amplifier and between the first two stages. The inductances combine with existing parasitic capacitances to create low-pass filters which pass the video signal from the camera but block the higher frequency transmitted television signals.

Abstract: A television camera which scans an image provides a camera video signal having an amplitude representative of light received from an element of the image being scanned. Prior to a scan a sync pulse is generated which increments a raster counter. Accordingly, the roster counter provides a signal representation of a cumulative number of scans of the image. During the scanning, clock pulses increment a horizontal deflection counter which provides a signal representation of a horizontal deflection number corresponding to the horizontal coordinate of the line of sight. When the cumulative number of scans equals the horizontal deflection number, a comparator provides a gating signal which causes a sample and hold circuit to store a sampled video signal having an amplitude equal to the amplitude of the camera video signal. The sampled video signal is provided to the input of an analog to digital converter for conversion to digital signals which may be stored in a digital computer.

Abstract: The deleterious effects of backscattering on a video image received from a urbid environment is minimized by using a vertical raster scan combined with appropriate filtering between the camera and monitor.

Abstract: A method of automatically focusing an optical system onto an image includes deriving a measure of the contrast for each of a plurality of images obtained at different settings of the optical and selecting as the final setting that setting which corresponds to the greatest contrast, the measure of contrast being derived from the distribution of selected image elements in a grey scale. Apparatus for carrying out the method uses an image converter to produce the image of the optical system for examination by a grey level measuring device which measures the grey values of a number of image elements.The distribution of the measured grey values within a grey scale is registered in a memory and this information is used by an electrical calculating system which calculates the value of a contrast function for the particular image being examined.

Abstract: An automatic control to the optimum lens adjustment in an ACT gun in a television camera tube. A variation in the cathode and control electrode potential during the line flyback requires an adaptation of the lens voltage for optimum target erasing action. In the circuit a measurement of the anode current in the gun is effected because for an optimum target erasing action during the line flyback it is found that this current must be at a minimum. A measurement is effected about an adjusting point. In case of unequal current the optimum value is not yet reached and an adjusting point displacement is effected towards the optimum value whereafter a subsequent measurement is effected.