Abstract:
According to an aspect of the present invention, a power detector including a photodiode and a logarithmic transimpedance amplifier is mounted inside a hermetically sealed package in such a way that the photodiode and the logarithmic transimpedance amplifier are located on the same thermally conductive substrate.
Abstract:
According to the present invention, a photoelectric converter comprises a plurality of substrates, which are located adjacent to each other and on which a plurality of photoelectric conversion devices are two-dimensionally arranged, either scan circuits or detection circuits, at least, that are arranged on two opposing sides of the photoelectric converter, whereby scanning directions either from the scan circuits or from the detection circuits, which are arranged on the two opposing sides, are capable of being set so as to be performed in like directions.
Abstract:
Low intensity light is incident upon a photodiode whose output is coupled to an integrator. The output of the integrator is coupled to an input of an A/D converter, whose output is coupled to a microprocessor, whose output is coupled to a filter. A second output of the microprocessor is coupled to a gate electrode of a FET to provide a reset signal to the FET to reset the integrator. The microprocessor compares the digital samples of the integrated signal from the A/D converter and, firstly, generates the reset signal if a sample is beyond a set limit, and, secondly, calculates delta values between adjacent samples and interpolates the delta values for the reset periods so as to provide a continuous data stream which can be filtered by a filter matched to the form of the original signal.
Abstract:
Optical receiving methods and systems are disclosed. One such optical receiving system includes an optical amplifier operable to produce amplified optical signals satisfying a filterless detection specification limit, and an optical detector locatable in unfiltered communication with the optical amplifier to receive the amplified optical signals therefrom.
Abstract:
A low light level image directed to a photocathode in a vacuum causes release of electron which bombard a CMOS imager including passive pixel sensors which in turn generates an electronic image which is fed out of the vacuum and is used to create useful images corresponding to the low level input image. A camera and other low light imaging devices are described.
Abstract:
Optical detector capable of operating in proximity mode or in proximity with background elimination mode, including an emission system and a reception system having hardware and software detection and configuration means capable of recognizing the appropriate mode by measuring the distance of the background, comparing a reception signal with at least one threshold, and automatically switching the reception system into proximity mode or proximity with background elimination mode depending on the result of the comparison.
Abstract:
A system for the photometric calibration of streak cameras and similar imaging devices provides a precise knowledge of the camera's flat-field response as well as a mapping of the geometric distortions. The system provides the flat-field response, representing the spatial variations in the sensitivity of the recorded output, with a signal-to-noise ratio (SNR) greater than can be achieved in a single submicrosecond streak record. The measurement of the flat-field response is carried out by illuminating the input slit of the streak camera with a signal that is uniform in space and constant in time. This signal is generated by passing a continuous wave source through an optical homogenizer made up of a light pipe or pipes in which the illumination typically makes several bounces before exiting as a spatially uniform source field. The rectangular cross-section of the homogenizer is matched to the usable photocathode area of the streak tube. The flat-field data set is obtained by using a slow streak ramp that may have a period from one millisecond (ms) to ten seconds (s), but may be nominally one second in duration. The system also provides a mapping of the geometric distortions, by spatially and temporarily modulating the output of the homogenizer and obtaining a data set using the slow streak ramps. All data sets are acquired using a CCD camera and stored on a computer, which is used to calculate all relevant corrections to the signal data sets. The signal and flat-field data sets are both corrected for geometric distortions prior to applying the flat-field correction. Absolute photometric calibration is obtained by measuring the output fluence of the homogenizer with a “standard-traceable” meter and relating that to the CCD pixel values for a self-corrected flat-field data set.
Abstract:
A bus system and an imager for transferring signals from a plurality of signal streams to an output includes a plurality of signal buses in parallel and a control system. The control system multiplexes the signals from two or more of the plurality of signal streams onto two or more of the plurality of signal buses and allows the signals to substantially charge each of the two or more of the plurality of signal buses before demultiplexing the signals to the output. A method for transferring signals includes multiplexing signals on to two or more of a plurality of signal buses and allowing the signals to substantially charge each of the two or more of the plurality of signal buses before demultiplexing the signals to an output.
Abstract:
A photoelectric switch emits pulsed detection light and outputs a light detection signal as reflected light is received. For generating an on-off judgment output for switching on and off, the level of the light detection signal is shifted towards a specified level during a specified light receiving period by an amount corresponding to the difference between the specified and the level of the light detection signal at a time immediately before the pulsed detection light is expected to arrive. On the basis of thus level-shifted signal, it is determined whether at least one of the conditions for generating the on-off judgment output is satisfied. The on-off judgment output is generated at least on the condition that the levels of the light detection signal at specified timings are in a specified size relationship. According to another embodiment, pulsed detection light is emitted at least three times per cycle of noise from a fluorescent lamp and comparisons are made between a specified level and the level of the light detection signal whenever a peak of the pulsed detection light is expected to arrive, and the on-off judgment output is generated according to the majority of the results of comparisons made during a period of light emission.
Abstract:
A photo switching device includes first and second terminals respectively coupled to a power source and a load. A bi-directional current routing circuit including a rectifying bridge is connected to the first and second terminals to receive electricity from the first and second terminals and has positive and negative output terminals. A switching/driving circuit is connected between the positive and negative output terminals for selectively conducting an output current of the bi-directional current routing circuit from the positive output terminal to the negative output terminal. The switching/driving circuit includes a silicon controlled switching device having a gate coupled to and controlled by a controlling circuit to switch between open condition and closed condition. The controlling circuit includes a photo detecting device connected to a gate of a gate controlled device. The gate controlled device has an output coupled to and controlling the gate of the silicon controlled switching device.