Showing papers on "Image sensor published in 1984"

Image sensing apparatus having a low-resolution monitor, means for reducing the amount of information in an image signal, and switching means for reducing power consumption in various operating modes

Abstract: An image sensing apparatus is provided with an image sensor having picture elements; an electronic monitor having a number of scanning lines fewer than the vertical picture elements of the image sensor; and a driving circuit for reading from the image sensor a fewer scanning lines when the apparatus is in a monitor mode than when the apparatus is in an image sensing mode. The driving circuit reads the image sensor in a non-interlacing manner in the monitor mode. A switching circuit shuts off power to unused circuits when the apparatus is in various operating modes.

Solid state image sensor with high resolution

Abstract: of the Disclosure There is disclosed a solid state image sensor including an interline transfer charge coupled device (IT-CCD) serving as an area image sensor and a vibrating plate for vibrating or swinging the IT-CCD in a plane orthogonal to an incident image light, horizontally, periodically and relatively to the incident image light in a given vibration mode. When the solid state image sensor is applied for NTSC television system in which one frame is composed of two fields, the IT-CCD is vibrated so that it senses an image at different positions during the two fields periods. As a result, a reproduced picture has a resolution which is obtained as if the number of picture elements of the image sensor per se is doubled.

Analysis And Processing of LANDSAT-4 Sensor Data Using Advanced Image Processing Techniques And Technologies

Abstract: Techniques have been developed or improved to calibrate, repair, geometrically correct, and extract information from Landsat-4 satellite data. Statistical techniques to correct data radiometry have been evaluated and have minimized striping and banding. It is shown that unless these statistical techniques are used, striping will result even with perfect calibration parameters. Algorithms have been developed to replace data from failed detectors and to reduce coherent noise. The Landsat-4 data have been geometrically corrected to conform to a 1:100 000 map reference to an accuracy of about 41 m. The data were then recorded onto film, and image products produced that can serve as low-cost accurate map products. To decrease the dimensionality of the Landsat-4 data, principal component transformation of the data to four significant new bands was performed, and the results compared with latest available land use maps. The transformation is useful for land use analysis and in delineating vegetation anomalies which appear to reflect areas underlain by altered serpentinite. A range of image processing systems have been used to process the satellite data, including general purpose, special purpose, and personal computers. These systems are described, along with their processing performance. Index Terms-Digital Image Processing, Thematic Mapper, Multispectral Scanner, Calibration, Geometric Correction, Mapping, Digital Terrain, Enhancement, Noise Removal, Personal Computer, Entropy, Principal Components, Banding, Striping, Information Extraction, Geology, Land Use.

Microwave thermoelastic tissue imaging - System design

Abstract: A microwave-induced thermoelastic tissue imaging system is proposed as a new and promising imaging modality. lt possesses unique features that permit noninvasive imaging of tissue characteristics which are not identifiable by otber techniques. It uses nonionizing radiation and relies on a beam of impinging microwave energy to launch an acoustic wavefront into tissue. This thermoelastic wave of pressure propagates through the tissue and is detected by a two-dimensional array of piezoelectric transducers positioned on the body surface to give an image of the intervening tissue structure. Signals from the output of this transducer array are amplified and band-limited. A computer-controlled data acquisition system samples and converts them to digital form for further processing. A hybrid paralleljserial design for dividing the array into segments and collecting data from each segment sequentially is used. The area image sensor offers inherent geometric stability essential for reliable measurement. Error in scan position is not a conctrn, since mechanical scanning is not involved. The gray Ievel resolution is 256 after digitization, and the spatial resolution is 5 x 5 mm. These resolutions, along with a calculated signal-to-noise ratio (SNR) greater than 2500, are sufficient to provide structural information needed to render microwave-induced thermoelastic imaging a useful, noninvasive method for imaging biological tissues.

Advances in streak camera instrumentation for the study of biological and physical processes

Abstract: Advanced streak camera technology and related instrumentation are reviewed. Streak cameras Combined with a direct video readout provide real-time and two-dimensional analysis to measure picosecond luminous phenomena with a detection sensitivity of a few photoelectrons. Streak cameras can be used to analyze luminous processes in the biological and medical fields.

Utilization of Spaceborne SAR Data for Mapping

Abstract: Recent developments in automated processing of digital SEASAT SAR imagery have made feasible the generation of large-scale high-resolution maps. Standard preprocessing of raw data into digital images results in geometrically distorted imagery. Computer algorithms have been developed for unsupervised pixel location, geometric rectification, and mosaicking of multiple-image frames without ground control points. These algorithms utilize knowledge of the spacecraft trajectory data, the imaging geometry, and the coherent properties of the sensor to generate the required processing parameters. This paper discusses the advantages as well as the inherent limitations of this technique, analyzes the associated errors, and presents results using SEASAT SAR imagery. Also discussed are the results of the recent shuttle imaging radar (SIR-A) experiment as well as a follow-on experiment (SIR-B) planned for 1984.

Interline CCD image sensor with an antiblooming structure

Abstract: A ⅔-in 384 (H) × 490 (V) element interline CCD image sensor with a new antiblooming structure was developed. Blooming was suppressed without sacrificing photosensitivity and dynamic range by means of a vertical overflow drain positioned under (rather than beside) a photodiode. For 10-percent vertical height illumination the smear signal was reduced to 0.05 percent of the illumination signal. Well-balanced performance, namely, large dynamic range (72 dB), low random noise (65 rms noise electrons per charge packet), high-contrast transfer functions for horizontal and vertical directions, and a spectral response similar to the luminous efficiency curve were obtained under moderate operating conditions.

Inspection method and apparatus for a mask pattern used in semiconductor device fabrication

Abstract: An inspection method and apparatus for a mask pattern such as a reticle pattern used in the fabrication of a semiconductor device is disclosed. The mask pattern is inspected by an imaging sensor mounted on a stage on which a fabricated object is also mounted. The imaging sensor converts an optical image of the mask pattern which is intended to be exposed on the object to a video signal and it is inspected by comparing it with another video signal provided from data for designing the mask pattern. This inspection is made before the process of exposing the mask pattern on the fabricated object in order to avoid a waste of time in the semiconductor pattern process.

Computerized video imaging system

Abstract: A computerized video imaging system is provided which includes a target mount for supporting a target photographic transparency. A lamphouse is positioned to pass light through the transparency and includes light sources for a set of primary colors. An image sensor is positioned to receive light passing from the lamphouse through the transparency and generates video signals representing hue and intensity of the light. Image storage means are provided for storing color reference representations of the reference transparency. A color video monitor receives signals related to the reference representations and the target video signals. A computer interfaces with the light source and the image storage to calculate photographic color correction values for the target transparency.

Compact optical imaging system

Abstract: A compact optical imaging system with application to a viewing head of an endoscope. A lens assembly gathers and focuses light into parallel rays which are turned 90° from the lens assembly optical axis. A planar image sensor is oriented parallel to the lens assembly optical axis and receives the light which has been turned. The light enters a glass plate serving as the back side of the image sensor and impinges on active light-sensitive elements on a silicon layer deposited on the glass plate. A substrate is bonded on the silicon layer and supports circuitry for buffering and driving signals to and from the image snsor. The substrate has a plurality of slots aligned with the bonding pads of the image sensor to permit electrical connection between the buffering and driving circuitry and the image sensor.

A Survey Of New Techniques For Image Registration And Mapping

Abstract: An important problem in any onboard imaging system is the rectification and registration of images generated by onboard sensors. Accurate registration is a key requirement for detecting changes (in position, brightness, texture, boundary, etc.), from one sensed image to the next, as well as classification of data for intelligence gathering and vehicle guidance. This paper discusses techniques of finding match points in pairs of images and performing geometric corrections and unwarping to compensate for systematic and random variations in the flight path, ephemeris, and sensor response. Techniques of resampling and interpolation of image data are reviewed, and the particular characteristics of sensors operating over a wide spectrum from visible through infrared and microwave are discussed. Particular attention is given to the rectification and registration of synthetic aperture radar (SAR) imagery.© (1984) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Method for correcting beam intensity upon scanning and recording a picture

Abstract: A method for automatically correcting variations in intensity of laser beams output from a projection lens, which variations occur due to variations of a spectrum pattern of optical fibers when their tip portions move, by paying attention to each of focal points of an image sensor which focal points correspond respectively to the optical fibers, comparing the sum of signal outputs from regions of the image sensor, which regions correspond respectively to the laser beams, with a signal output corresponding to a standard beam intensity required for the exposure of a photosensitive material to determine a value to be corrected, and then feeding the value back to acousto-optic light modulators so as to change the modulation efficienties of the acousto-optic light modulators.

Color video endoscope system

Abstract: A color video endoscope system having a control unit compatible with various endoscopes. Each endoscope generates unique signals to the control unit to optimize the clocking out of data from the solid state image sensor, to optimize the processing of data received from the image sensor, and to identify the size and location of the image formed on the image sensor so as to control the image formed on the monitor. The control unit generates alternating fields of red, green and blue light through the endoscope light guide with blank fields between the color fields, during which time data is clocked out of the image sensor, thereby preventing image "smear" caused by immediately successive color fields.

An interline CCD image sensor with reduced image lag

Abstract: An undesirable image lag with a long time constant was found in the interline CCD image sensor having an n+-p-junction photodiode (PD). This paper clarifies the image lag mechanism and proposes a new photodiode structure having very little image lag. The image lag measurement method and the experimental results are also given. The experimental results quantitatively agree with the analytical model, in which signal electrons are assumed to be transferred from the PD to the vertical CCD as a small subthreshold current. To eliminate the image lag, a p+-n-p-structure PD with low donor concentration is proposed, in which all the signal electrons can be quickly transferred before the subthreshold condition begins. As a result, decay lag values for the first and the second fields were reduced to half and no decay lags were observed after the third field.

Image reader suitable for manual scanning

Abstract: An image reader of hand scanner type has a transparent support for fixing an original on a table in position, a reading head, LEDs for irradiating the original, an imaging sensor array for reading the original image further LEDs and sensor for detecting the head scanning position, a control circuit including a turn on circuit and/or an alarm control circuit, and a display LED. The LEDs for image reading are turned on only during image reading. When manual scanning is performed too fast and further signal processing cannot be performed, this can be signalled to the operator by the display LED.

Signal processor for an imaging sensor system

Abstract: A signal processor for use with an imaging sensor system that provides enhanced video imagery. The signal processor may be coupled to a FLIR system, for example, which comprises a plurality of detectors that are scanned across an image scene and reference temperature source during separate portions of each scan cycle. The signal processor comprises an input processor coupled to the imaging sensor system which processes analog signals derived from each of the plurality of detectors. The input processor normalizes the analog signals relative to one another during the active portion of the scan cycle based upon stored data derived from a predetermined sensor responsivity calibration procedure. This normalization function equalizes the gains associated with all channels of the sensor system. The input processor also restores the DC levels of each of the sensor channels to respective DC values related to the reference temperature source during the inactive portion of the scan cycle. This function is performed during the calibration procedure and while the system is in operation. The input processor digitizes the signals which are applied to a scan converter. The scan converter stores the digitized signals and converts the stored signals into signals which are compatible with a video monitor employed to view the image. An output processor is coupled to the scan converter that is employed to process signals in a manner which permits software-controlled digitized image enhancement thereof, and which converts the enhanced signals into analog video output signals compatible with the video monitor.

Swing-driven solid-state image sensor

Abstract: According to an image pickup device, a swing-driver unit (30) is provided for vibrating an image sensor unit (10, 50), thereby causing the image sensor unit (10, 50) to perform an image pickup operation in such a manner as to periodically shift to different sampling positions at different time points in one frame period. The swingdriver (30) comprises a pair of plate-like bimorph piezoelectric elements (32a, 32b) for stably supporting the image sensor unit (10, 50). The image sensor unit (10, 50) and the piezoelectric elements (32a, 32b) are sealed in a ceramic frame body (20) in a compact manner. The electrical connection between the image sensor unit (10, 50) and lead wires (24) formed on the frame (20) is performed by a flexible film connector (60). The electrical connection between the piezoelectric elements (32a, 32b) and the lead wires (24) is performed by wiring patterns (29) preformed on the frame (20).

Automatic focus detecting device

Abstract: An automatic focus detecting device comprising an image sensor for electrically converting distributions of two images of an object which are formed by two restricted light beams passed through different areas in a zooming lens system into time sequence video signals which in turn are extracted at predetermined extraction intervals and directed to a correlator for deciding the degree of agreement between the two images. The video signal extraction is effected in two operation modes; one is for a high accuracy focus detection and the other for a rough accuracy focus detection. In the former operation mode, a time sequence video signal of a narrow image is extracted at short intervals and on the other hand, in the latter operation mode, a time sequence video signal of a wide image is extracted at long intervals. The automatic focus detecting device is set up to the rough accuracy focus detection mode in the early stage of operation and changed to the high accuracy focus detection mode when a rough focus detection is attained.

Color image sensor with improved resolution having time delays in a plurality of output lines

Abstract: A solid-state color image sensor and a method for operating such an image sensor in which high resolution is provided by delaying outputs from the various pixels in the sensor array by delay times determined in accordance with the actual positions of the pixels in the row direction of the array. Pixels are read out simultaneously in groups of three, one for each of white, cyan and yellow. The delays are imposed upon two of these. The delayed and undelayed outputs are combined with sum/difference circuits to produce chrominance and luminance signals. Preferably, the pixels have hexagonally shaped light sensitive areas to maximize the light sensitivity of each pixel and hence the resolution of the device.

Surveying satellite incorporating star-sensing attitude determination subsystem

Abstract: A system for surveying features of a planet includes a novel attitude determination subsystem. A satellite includes an earth imaging sensor (106). The sensor is alternately directed at the earth and a predetermined star field. The optical detections are converted to electronic signals by a sensor electronics module (332). The outputs of the sensor electronics module corresponding to the times when the sensor is directed toward earth are processed by a signal processor (336), the output of which is a data stream which permits image reconstruction by a ground station computer. The outputs of the sensor electronics module corresponding to the times when the sensor is directed toward the star field are directed through onboard star detection thresholding electronics. A programmable threshold device (342) selects detections of target stars within the star field. A star data buffer (344) stores these target star detections for transmission to earth at a convenient time. This data stored by the buffer is compact star attitude determination data required for accurate gridding of the earth image data transmitted from the signal processor. In an alternative embodiment, an earth imaging sensor is occasionally pointed at a limited portion of the star field, such special motion being controlled from the satellite. In both embodiments, compression of star field data is accomplished by means located onboard the satellite. The compressed star field data is subsequently used to accurately determine sensor attitude.

Blooming suppression in a CCD imaging device

Abstract: A CCD solid state image sensor device. During the integration period the surface in the image pick-up section is switched alternately into inversion and into accumulation. Any excess of charge carriers which results from possible overexposure can thus be drained by means of recombination via sufaces states.

Image pickup system

Abstract: An image pickup system has an image sensor including a plurality of photodetectors arranged in two dimensions and an optical system having a lens for forming an image on the image sensor so that the image sensor produces picture data. A vibrator is provided for vibrating the image on the image sensor so as to oscillate the picture data, and a scanner is provided to be operative in synchronism with the vibration of the image for changing the oscillated picture data to data for a fixed image. A memory is provided for storing the data for a fixed image and a majority logic circuit is provided for selecting the most reliable data from the data stored in the memory and for producing a picture data for the image on the image sensor.

Image signal reproduction circuit for solid-state image sensor

Abstract: In an image sensing system, a solid-state image sensor is mounted on a vibration stand in a manner as to vibrate horizontally to an incoming light in synchronization with one frame period, thereby sensing while alternatively displacing at different sampling positions in two field periods. Field image signals from the image sensor is supplied, through a signal processor, to a signal reproduction unit which includes a carrier generator for producing first and second carrier signals having the same frequency as the horizontal readout frequency of the image sensor and a phase in reverse to one other in the field periods, and an AM modulator for amplitude-modulating the carrier signal. The amplitude modulation field signals thus obtained are sliced at a suitable level by a slicer and then synthesized each other to obtain a frame image signal.

Electronic imaging system and technique

Abstract: A method and system for viewing objects obscurred by intense plasmas or flames (such as a welding arc) includes a pulsed light source to illuminate the object, the peak brightness of the light reflected from the object being greater than the brightness of the intense plasma or flame; an electronic image sensor for detecting a pulsed image of the illuminated object, the sensor being operated as a high-speed shutter; and electronic means for synchronizing the shutter operation with the pulsed light source.

Solid-state image pickup device

Abstract: A solid-state image pickup device and a still picture recording device in which blooming and vertical smearing are eliminated. A drive circuit applies vertical and horizontal synchronizing signals to an image pickup element or area image sensor, and an exposure control circuit applies an exposure time control signal thereto for controlling the length of the exposure time according to the intensity of the image light exposing the pickup element or sensor. A scanning stopping circuit stops the application of the synchronizing signals to thereby stop the scanning of the area image sensor for a period of time starting from a time before the start of exposure until the occurrence of a first pulse of the vertical synchronizing signal after application of the exposure time control signal.

Means for recording, analysing by measuring techniques, and/or controlling successive phases of technical processes

Abstract: 1. Device for the detection, measurement-technical analysis and/or regulation of technical process sequences, preferably for the checking of assembly operations, docking sequences, for robot guidance or for the steering of projectiles, with the use of at least one opti-electronic image sensor and a grey value image processing equipment which is arranged downstream of the image sensor or sensors and displays an equipment for the digital quantisation of the sensor images detected by the image sensor or sensors or of preset reference images into more than two grey value stages, an equipment for the actual value detection of the digitally quantised sensor images or for the target value presetting of the digitally quantised reference images and an equipment for the comparison of target value and actual value between the digitally quantised grey value images of the sensor or sensors and the digitally quantised reference images as well as, if required, for making available evaluating signals and/or setting signals for setting members connected therebehind, characterised thereby that real time data reduction equipments (7 or 12), which reduce the digitally quantised image information of the sensor or sensors (5) and the preset digitally quantised reference images to a few grey value features, are connected downstream of the equipments (6 or 13) for the digital quantisation of the sensor images or of the reference images and that the equipment (10) for the comparison of target value and actual value is constructed as real time data comparison equipment which performs a comparison of target value and actual value within one or more image periods.

Charge-Coupled Device Image Acquisition For Digital Phase Measurement Interferometry

Abstract: Direct phase measurement interferometry can provide a fast and accurate means of obtaining surface data. Solid-state detector arrays are ideal imaging devices for these instruments. These imagers can be coupled to micro-computers for phase calculation. This article discusses the use of CCD arrays and techniques for digitizing and interfacing these arrays to microcomputers.

Method and apparatus for processing signals from a solid-state image sensor.

Abstract: The output signals from a solid state image sensor (10) having defective photosites causing corresponding defects in the output signals are processed by correcting the defect-related portions of the signals, and image-enhancing (16, 18, 20, 38) only those portions of the signals not in the neighbourhood (as defined herein) of the defect-related portions. Those portions in the neighbourhood of defect-related portions are not subjected to image-enhancement.

X-Ray Imaging With Two-Dimensional Charge-Coupled Device (CCD) Arrays

Abstract: Two basic approaches to digital radiography have been thoroughly investigated in the last decade. In one, the traditional video chain is modified, and the output of the camera is digitized and analyzed by a computer to produce an image of the area of the body being examined. The other approach uses a linear detector array to generate a sequential series of line images as the array is scanned across the area being observed; the line images are then combined by a computer to form a two-dimensional image. We are investigating the characteristics of a third method, a prototype digital radiography system in which two-dimensional diode arrays (CCD) are fiberoptically coupled directly to either a scintillating fiberoptic plate or to a fluorescent screen. In this paper we describe the- concepts and design configuration of this approach, as well as preliminary results from several phantom studies. Our results indicate that high resolution, high signal-to-noise ratio imaging can be attained with this method.

Method and device for detecting defect of fine pattern

Abstract: PURPOSE:To inspect a complicate and fine pattern automatically by separating optical images of light visual field lighting and dark visual field lighting in the middle of an optical path of detection, and detecting and processing pattern shape information, density, and hue variation simultaneously. CONSTITUTION:The device consists of a dark visual field lighting system whose wavelength (alpha) by a narrow-band filter 3, light visual field system which is limited to light containing no alpha by a filter 9, image formation system, binary- coding circuit 16, memories 17 and 20, image comparing circuits 18 and 21, decision part 22, control mechanism for the whole, etc. Light visual field lighting and dark visual field lighting are performed at the same position and their respective images are formed on image sensors 14 and 15. In this case, a thin- film mirror 13 performs wavelength and optical path separation. Thus, the images are detected, and then a defect of a pattern shape is detected as abnormality of the plane shape of a pattern edge and abnormality of the thickness of a transparent thin film causes variation in brightness and hue, so they are inspected separately at the same time. Further, when a linear image sensor is used, the circuits 18 and 21 compare signals with signals which are one chip before and annunciate the results.