Abstract:
A sensitive photon detection system generates an electronic photon sensor signal as a K factor times a number N photons per unit time. The system is configured by combining a separate optical amplifier with a gain factor K1 with a photo detector with a gain factor K2 such that K may be realized as the product of K1 and K2. The values of K1 and K2 are chosen to meet a predetermined K while optimizing a signal quality of the photon sensor signal. The optical amplifier may be preceded by a photon gathering device and/or a light chopping device to further optimize system performance. Further, the photon sensor signal may be further processed analog circuitry or may be digitized and processed using digital signal processing to generate an enhanced photon sensor signal with enhanced signal quality by adding gain and/or bandwidth limiting.
Abstract:
A light amount measuring device, according to the present invention can include, a light-receiving sensor capable of outputing a voltage corresponding to an amount of incident light, an A/D converting portion capable of converting an input voltage into a digital value, a light amount calculating portion capable of calculating the amount of light incident on the light-receiving sensor on the basis of the digital value obtained by conversion by the A/D converting portion, a resistor connected between the A/D converting portion and the light-receiving sensor, a zener diode has one end connected between the A/D converting portion and the resistor, wherein the zener diode is capable of allowing a breakdown current flow from the one end to another end if an output voltage from the light-receiving sensor is not less than a predetermined value.
Abstract:
A method and apparatus for braking an AC motor in the higher portion of its speed range includes substantially reducing flux before applying reverse torque commands to brake the motor. A DC link bus regulator is employed to prevent increases in bus voltage and frequency.
Abstract:
The invention concerns an irradiation device for testing objects coated with light-sensitive paint, comprising a EUV radiation source, an optical system for filtering the radiation of the EUV radiation source a chamber for receiving the object, as well as systems for intersecting the trajectory of the rays on the object. The invention also concerns a method for operating such a device. The invention aims at obtaining as quickly as possible an illumination at least partly simultaneous of several irradiation fields, with different doses, by using an inexpensive laboratory radiation source without resorting to complex optical systems. Therefor, the invention provides a device comprising a simplified and compact optical system, with closable diaphragm apertures located in front of the object to be irradiated and at least one control sensor placed on the trajectory of the rays and enabling the radiation dose to be measured.
Abstract:
Disclosed is an apparatus that includes an output unit having a photoelectric converting element, for producing a signal corresponding to light incident on the photoelectric converting element, a restricting unit for restricting a light receiving region of the photoelectric converting element to one of a first region and a second region, and a calculating unit for calculating a sensitivity of the first region, on the basis of an output signal related to the first region and obtainable through cooperation of the output unit and the restricting unit, and of an output signal related to the second region and obtainable through cooperation of the output unit and the restricting unit.
Abstract:
A device for controlling an amount of light of a lighting unit for use in an endoscope that is used to view an image of an object. A light shielding system shields light generated by a light source and transmitted to the endoscope and a stepping motor drives the light shielding system for a plurality of predetermined time intervals. A system detects a brightness of the image during each of the plurality of predetermined time intervals and an input system inputs one of a plurality of desired brightnesses of the image. A generating system generates a predetermined number of pulses during each of the plurality of predetermined time intervals, the predetermined number of pulses being transmitted to the stepping motor and a system determines an angular position of the light shielding system. A setting system sets one of a plurality of allowed brightness ranges of the image in response to the determined angular position of the light shielding system and a system determines whether the detected brightness is within the set one of the plurality of allowed brightness ranges.
Abstract:
A device for controlling an amount of light of a lighting unit for use in an endoscope, used to view an image of an object. The device includes a light shield system for shielding light generated by a light source and transmitted to the endoscope. A stepping motor drives the light shield for a series of predetermined time intervals. Brightness of the image is detected during each of the time intervals and pulses are generated during each of the time intervals. One of a plurality of brightness ranges is set in accord with desired brightness of image. A determination is made as to whether the detected brightness is within one of the ranges. The pulses generated are used to drive the stepping motor in each of the plurality of time intervals.
Abstract:
An electronic device for measuring extremely faint light emissions comprises a photomultiplier tube surrounded by a sleeve made of a material which is a good heat conductor, cooled to a low temperature and insulated from the outside, a thermally insulating and optically transparent lightguide body being stably glued to the photocathode of the photomultiplier tube to receive the light radiation emitted by a specimen to be examined, which is inserted in a cavity of a supporting structure holding a rotary body which can be turned in front of the lightguide body, so as to operate as a shutter for the lightguide in a first turned measurement position thereof to allow measurement of the dark signal and then allow, as the rotary body and the specimen held therein are turned to a second measurement position, to measure the light emission from the specimen.
Abstract:
A sensor circuit for detecting light hazards or bright light sources that will cause discomfort. The sensor and sensor electronics which provide a wide sensitivity range which is fully automatically adjustable, and which has the ability to detect point sources of light. The sensor further has the ability to distinguish low power stable light generated from a small welding arc from bright ambient light or even direct sunlight.