Abstract: A low cost, low power photometric circuit suitable for use in a low end camera includes a first counter for counting successive pulses produced by a first oscillator having a substantially constant oscillation frequency and a second counter for counting successive pulses produced by a second oscillator having an oscillation frequency which varies in accordance with ambient brightness. The ambient brightness is judged according to outputs of the counters so that even if the oscillation frequency of the second oscillator varies only slightly due to a change in ambient brightness, the slight variation is easily detectable as an accumulated count value. Accordingly, costly, high-precision components are not needed. The low cost photometric circuit requires no microcomputer, analog/digital converter or comparator and can be fabricated in a single integrated circuit operated at a low voltage of 1V or less, and is thus suitable for incorporation into a low end camera.

Abstract: A light measuring apparatus comprises an oscillation circuit, a first delaying circuit for delaying an output waveform of the oscillation circuit in accordance with a peripheral brightness, a second delaying circuit for delaying an output waveform of the oscillation circuit for a predetermined period of time, and a brightness judging circuit for judging a peripheral brightness in accordance with outputs of the first and second delaying circuits.

Abstract: A light-received position detecting circuit includes a light receiving portion 10 formed by plural photodiodes arranged side by side for detecting light to generate a photoelectric current, and a resistor group RR formed by plural resistors RR1 to RRn-1 connected in series and the photodiodes are correspondingly connected to the respective resistors to divide the photoelectric current from a light emitting portion 31 into photoelectric current parts according to the position of generation of the photoelectric current. First and second current detecting amplifiers 12 and 16 for generating detection signals corresponding to the photoelectric current parts are connected to the opposite ends of the resistor group RR, respectively. A third current detecting amplifier 14 for dividing the light receiving portion 10 into light receiving sections and detecting the photoelectric current part is connected to selected one of the resistors located in the intermediate portion of the resistor group RR.

Abstract: An exposure control system for the photographic recording of a microscope image comprises a two dimensional photographic receiver arrangement for detecting the image brightness of the microscope image. The receiver arrangement is a component part of a camera system which is attachable to a standard camera part of a microscope. The receiver arrangement has an interface for transmitting image information of a microscopic object detected by the receiver arrangement to a viewing unit. A first input device is included to which the viewing unit is coupled for manual selection of at least one optical image region on the receiver arrangement. The intensity value of the image region forming a control signal for the exposure time of the photographic recording.

Abstract: A light meter comprising: a light sensitive charge storage array having at least one charge storage cell, and reading circuit means connected to said array for generating a light reading from charge stored in said array, said light reading being indicative of the quantity of light incident on said array; wherein said reading circuit means collects charge from said array and compares said collected charge to a threshold to generate said light reading.

Abstract: A flash device has a flash tube which generates light in response to electrical energy. The amount of light emitted by the flash tube is monitored by a circuit which is connected to means for adjusting the electrical energy supplied to said flash tube when a predetermined amount of light has been emitted to thereby increase the effective life span of the flash tube and maintain intensity level of the flash tube within a given tolerance.

Abstract: There is provided a photosensor having a photoelectric converter for converting incident light into a photoelectric current, and a function of removing noise light from imaging light including noise light and reflected from an object to be photographed. A plurality of photosensors each having the arrangement are used as an image sensor. A single photosensor having the arrangement or a plurality of photosensors each having the arrangement are used as a distance sensor. There is provided a photosensor in which a storage unit stores electric quantity corresponding to fixed light, and electric quantity corresponding to reflected light in the state wherein electric quantity stored in the storage unit is reproduced by a reproduction unit is introduced, and the difference therebetween is reproduced as an electric signal. A single photosensor having the arrangement or a plurality of photosensors each having the arrangement are used as a distance sensor.

Abstract: A photoelectric converter device having improved residual image characteristics and composed of a transistor having a control electrode region made of a semiconductor of a first conductivity type for accumulating carriers generated by an electromagnetic wave emitted by an object to be detected, a first main electrode region made of a semiconductor of a second conductivity type, and a second main electrode region made of a semiconductor of the second conductivity type, for performing an operation to accumulate the carriers, an operation of reading signals based on the carriers, and an operation of extinguishing the carriers, wherein carriers other than those generated by the electromagnetic wave emitted by the object to be detected are generated in or injected into the control electrode region. Thus, since the amount of excess majority carriers in the control electrode region after the extinguishing operation is always kept substantially constant, improved residual image characteristics are obtained.

Abstract: In a range finder, a capacitor for light emission is charged by turning off first and second switching elements and turning on third and fourth switching elements before light is emitted from a light emitting diode. A sum of a charging voltage of the capacitor for light emission and the voltage of a direct current power source is applied to the light emitting diode by turning on the first and second switching elements and turning off the third and fourth switching elements when light is emitted from the light emitting diode. At this time, an operation of the second switching element is controlled with a constant electric current by a constant current control circuit constructed by a transistor, a resistor for current limitation, a diode, etc. so that an electric current flowing through the light emitting diode is constant and a light emitting amount of the light emitting diode becomes constant.

Abstract: A ballistic optical camera trigger having an integrated circuit capable of onverting light to a proportional frequency, wherein the integrated circuit has a fast response time and a wide dynamic range which allows it to sense positive or negative changes in light fast enough to trigger without delay for high speed imaging without computational delays or jitter causing interference. The frequency output of the integrated circuit is tracked by a phase lock loop/voltage controlled oscillator to allow it to follow slow changes in light, but not fast changes in light caused by, for example, a projectile such as a bullet. The frequency output from the integrated circuit is provided to one input of a logic gate which receives at another input thereof, a shaped pulse from the phase lock loop/voltage controlled oscillator circuit, wherein the output of the logic gate is applied to a one-shot for outputting a trigger signal.

Abstract: An illuminant discriminator distinguishes a range of separate illuminants, including high efficiency fluorescent lighting, by modifying the frequency response of a signal output from a photodetector. A switchable high pass filter coupled to the photodetector has a first filter section with a first cutoff characteristic selected to pass signal components due to various types of lighting including high efficiency lighting, and a second section with second cutoff characteristic that separates out the high efficiency components. The high pass output is processed by a log amplifier to develop flicker frequency harmonics that are distinguished as to source illuminant by comparator stages. Undersampling artifacts due to high efficiency lighting are present in the mixed illuminant spectrum when the first filter section is operative, and positively identified as high efficiency lighting when the second section is operative.

Abstract: An arrangement e.g. for image generation and/or reading has first and second light element arranged substantially in two dimensions, control and addressing devices for activation of light or picture elements wherein at least the first light elements are real and form a thin matrix and the second light elements form a denser matrix wherein the position of each first light element at a given time corresponds to the position of a second light element. The addressing devices are spatially arranged or connected to at least each first element, and first as well as second light or picture elements are activated via said control and addressing devices.

Abstract: A reed switch is provided between a video camera and a battery pack circuit section. A current flowing when the video camera operates is detected by the reed switch. A video light is turned on or off on the basis of the detected current value. When the power source does not reach a specified voltage, the video light is turned off. The outer light amount when photographing is converted into an electric current by a phototransistor. When the current is less than a threshold level, the video light is lit or turned on. The threshold level is varied by a variable resistor.

Abstract: The invention relates to radiology systems and, more particularly in such systems, to a method that enables the effect of non-reciprocity of the radiographic film to be determined. This effect of non-reciprocity is expressed by coefficients CNRD(d.sub.i) which are a function of the photon dose rate (d.sub.i) on the film, the coefficients CNRD(d.sub.i) being obtained from the coefficients CNRT(t.sub.i) and the determination of the reference lumination L.sub.ref received by the film.

Abstract: A photometering device comprises: a generator for generating an analog voltage output which varies in accordance with a light intensity of an object field and is proportional to an absolute temperature; a reference voltage generator for generating a reference voltage output proportional to an absolute temperature; a switching device for switching the analog voltage output and the reference voltage output; a single output terminal for sequentially outputting the analog voltage output and the reference voltage output switched by the switching device; and an arithmetic operation device having a single analog-digital converter for converting the analog voltage output and the reference voltage output supplied from the single output terminal to digital signals for calculating a photometering value based on the digitally converted analog voltage output and reference voltage output.

Abstract: System and method for analyzing pulses from an excimer laser by measuring light energy rather than heat energy. The output of the laser is monitored with a photodetector to provide electrical current pulses corresponding to the intensity of the light in individual ones of the laser pulses. The current pulses are integrated to provide voltages corresponding to the light energy of the laser pulses, and the voltages are converted to digital signals. The digital signals are accumulated during the exposure period to determine the total light energy of the pulses during that period and also during a shorter interval of time during the exposure period. The light energy for the interval is divided by the length of the interval to determine the average intensity of the pulses during the interval. Displays are provided for the light energy and the intensity of the pulses, as well as the length of the exposure period.

Abstract: A photometer of a camera employs a MOS-type CPU having an open drain type transistor whose drain serving as an output terminal, a CMOS input terminal, and an input gate inverting an input with a value exceeding a predetermined potential. In the photometer, the transistor is set in a high-impedance state, thereby releasing a charge accumulated in a parasitic capacitor of a photodiode for generating a photoelectric current corresponding to an incident light amount. Thus, a voltage at the CPU terminal gradually increases, and, when it exceeds a threshold of a Schmitt inverter, the output of the Schmitt inverter is inverted. The time period from when the transistor is set in the high-impedance state to when the output of the Schmitt inverter is inverted is proportional to the photoelectric current. By measuring the time period, the photoelectric current value or luminance is detected.

Abstract: In an automatic exposure (AE) controlling method and apparatus according to the invention, a picturing area or a view is divided into a plurality of zones of which the central one is usually used for iris adjustment with the largest weight. The central zone is automatically expanded or reduced in the upper, lower, right-hand or left-hand direction(s) in accordance with differences in average luminance between the central zone and a respective one of the surrounding zones.

Abstract: A photometric circuit comprises a switching circuit which causes a photo conductive element which responds to the luminance of an object of measurement to be selectively connected with an oscillation circuit so that the photo conductive element functions as a frequency determining element and a frequency ratio calculating circuit which calculates a ratio of the oscillation frequency obtained when the photo conductive element is in connection with the oscillation circuit to the oscillation frequency obtained when the photo conductive element is not connected with the oscillation circuit. Thus, it is possible to reduce the required capacitance of the capacitor operating as a frequency determining element, lower the voltage required to drive the circuit and yet achieve high measuring accuracy.

Abstract: A light metering device includes a light detecting number having a plurality of light detecting elements arranged in a matrix for detecting brightness of smaller divisions into which a whole image field is divided, respectively, to define a plurality of light metering areas different in area in an image field so as to contain a smaller light metering area within a larger light metering area, and a calculating member for obtaining a mean brightness value of each light metering area by calculating an arithmetic mean value of the outputs from the light detecting elements defining each light metering area. The difference of mean brightness values of two adjacent light metering areas is compared with a predetermined critical mean brightness value to determine that lighting condition under which a subject exists is ordinary or unusual.

Abstract: A light measuring circuit including a light sensing device for sensing light and producing a signal representative of the light sensed, a compressing circuit for compressing the signal, a capacitor having one terminal connected to a predetermined voltage, a charging circuit responsive to the compressing circuit for charging the capacitor, a detecting circuit for responding to the voltage level of the capacitor, a switch for shorting the capacitor when closed for initiating charge of the capacitor by opening, and a delay circuit coupled to one of the charging circuits and the switch for delaying the onset of charge of the capacitor.

Abstract: A light measuring device having an automatic focus control mechanism including one-shot type focus control means for effecting focus control in one-shot type focus control mode and servo type focus control means for effecting focus control in servo type focus control mode, in which a field to be photographed is divided into a plurality of areas which are subjected to light-measurement, and a control circuit is provided to vary weighting for light-measurement of these divided areas according to the selection of the above-mentioned focus control mode effected by said automatic focus control mechanism.

Abstract: A photometric circuit for a camera has a photo-electric conversion element arranged to measure light in the middle part of the angle of view of the camera and a plurality of photo-electric conversion elements arranged to measure light in the peripheral parts of the angle of view. Of these peripheral light measuring elements, the elements disposed symmetrically with each other relative to the middle part of the angle of view are paired and connected in series with each other. Further, the series circuits thus formed are connected in parallel with the middle light measuring element.

Abstract: An input circuit which converts currents produced from a plurality of photo-sensitive elements arranged in a distance measuring apparatus. The input circuit has a switching element series connected to at least one of the photo-sensitive elements. When the switching element is operated, the output current of one of the photo-sensitive elements is supplied to a converting circuit which converts current into a voltage. Only one converting circuit is present. The output of the converting circuit is produced in a time series to a computing circuit. The computing circuit processes the signal thus received and produces a signal corresponding to an object distance.

Abstract: A distributed processor control system for use with a microimage recording apparatus includes a system control unit, a machine control unit and an operator control unit. The system control unit includes a microprocessor that provides supervisory or master control for the overall distributed control system. The machine control unit includes at least one microprocessor for controlling the operations of a plurality of electromechanical components within the microimage recording apparatus in response to commands and parameters provided by the system control unit and for providing status and error information and requests to the system control unit. The operator control unit includes a microprocessor for controlling the display of operational status and error indications and messages for viewing by an operator and for receiving manual operator entries for enabling normal operation of and diagnostics for the microimage recording apparatus.

Abstract: A light measuring device which is provided with a plurality of light sensitive elements and is arranged to selectively detect outputs of these light sensitive elements includes means for short-circuiting both terminals of the light sensitive element not required for detection in a light measuring mode selected out of different light measuring modes.

Abstract: A color printing control system for making prints from negatives having a color printer and a microprocessor. The output of photocells which read color negatives is applied to the microprocessor enabling it to calculate print time signals. These signals are applied, for example, to paddles and move them into the light path to terminate light exposure. A print test probe reads the density of the prints and is coupled to the microprocessor and forms a feedback loop which allows the microprocessor to adjust its internal values. In this manner, color balancing is performed and prints made from over and underexposed negatives have the same density as properly exposed negatives, without knowledge of paper characteristics and without operator setup calculations.

Abstract: To amplify an input current present at the input of a circuit arrangement with a feedback-coupled operational amplifier, two virtually equal potentials are built up in two different current paths with a common summing point. By means of the potentials, a current flow is produced for each current path. The current flow in one current path is determined by the input current, and the current in the second current path determined by a suitable choice of the impedances on the first and second current paths. The current in the second current path is greater by a multiple than the current in the first current path.

Abstract: An image information detecting device for detecting the density for printing is required to cover a wide dynamic range corresponding to the density scope of the original film as well as to cover the fluctuation in values caused by different lamps and filters used in the photometric system. It is also important in photographic printing process to detect the density information on a relatively wide area of a frame of a negative film or the like in order to determine exposure or correction amount. The present invention enables the use of a storage-type light receiving element over a wide dynamic range as well as segmentation of picture images of a film of a wide scope into a large number of picture elements for detection.

Abstract: In an exemplary embodiment, an X-ray image intensifier and a camera for photographing the X-ray image intensifier-output image, an automatic exposure timer which includes an integrator for detection of the light quantity per image and a threshold value switch for shut off of the X-ray tube upon attainment of a setpoint light quantity. The threshold value switch possesses a control input for determining the switch-off threshold which is connected to a correction circuit for comparing the actual value and the setpoint value of the light quantity and which so determines the threshold that the actual value is adapted to the setpoint value. The afterglow of the X-ray image intensifier following the occurrence of a switch-off signal is thereby compensated.

Abstract: A photosensor arrangement for providing an exposure influencing control signal in a photographic camera apparatus includes a photosensor array wherein the exposure influencing control signal comprises an average of the output signals from all the photosensors in the array excepting the output signals from those photosensors in the array which detect the highest and lowest scene light intensities.

Abstract: A measuring circuit for measuring the light intensity received by a photosensor comprises a photosensor which generates photocurrent proportional to the intensity of received light, an integration circuit for integrating the photocurrent generated and for measuring the intensity of light by measuring the time period from the start of integration until the integrated value reaches a predetermined level. In order to provide a wider dynamic output range, a signal generator which produces a monotonously changing voltage signal is connected to add its signal to the integrated signal.

Abstract: A photometric apparatus for a camera comprises a reference voltage circuit; an operational amplifier including a photoelectromotive element for photometry, an output terminal of said reference voltage circuit and an input terminal of said amplifier being connected through an impedeance element to a voltage divider tap of a battery; and a switching circuit for switching said reference voltage circuit to an operable condition as well as for changing set resistors which apply a bias current to said operational amplifier, in synchronism with a shutter releasing operation.

Abstract: A photometric circuit comprises an operational amplifier including a plurality of differential amplifiers, a constant current bias circuit for supplying a constant current bias to the differential amplifiers, and a bias control switching circuit which selectively connects the constant current bias circuit to one of the plurality of differential amplifiers in response to an external signal. A plurality of photoelectric transducer elements, used for purpose of photometry, are connected to differential inputs corresponding to the plurality of differential amplifiers, and the transducer element is selectively enabled for photometry in accordance with the external signal.

Abstract: Disclosed is a temperature compensation system for light measuring circuits. Said system compensates for the change, over temperature, of the output of the light measuring circuit by applying a bias source with a predetermined temperature coefficient. The system is designed so the bias voltage source is derived from the V.sub.BE (base to emitter voltage) difference between a pair of transistors, which difference is generated by the difference of current density at the junction of the pair of transistors obtained by flowing a pair of currents with a constant ratio independent of temperature.

Abstract: A multi-metering device comprises division of an object field into a plurality of areas and metering said plurality of areas and generating a plurality of photoelectric outputs corresponding to said plurality of areas, a binary circuit for standardizing said plurality of photoelectric outputs by the average output of said plurality of photoelectric outputs, and a classifying circuit for classifying the object field on the basis of said standardized outputs and operating and extracting a proper metering output by the classifying output.

Abstract: In a photographic device, there are provided (a) a means for measuring luminous intensity distribution on an object and (b) a screen means for controlling gradation of an image to be formed on a photosensitive material in accordance with the luminous intensity distribution and/or maximum/minimum luminous intensity difference of the object measured by the means (a).

Abstract: A photometric apparatus for a camera includes a diode for logarithmic compression and a semiconductor analog switch in series connection between an output terminal of a first operational amplifier and a second operational amplifier forming an integration circuit by connecting a photoelectric transducer element for a photometry purpose. A logarithimic compression signal for an exposure display and a photocurrent integration signal for an exposure control are derived from the first and the second operational amplifier, respectively.

Abstract: A photoelectric conversion circuit comprises a pair of cascade connected semiconductor switching circuits, each of which is formed by a CMOS inverter. A pair of oppositely poled, series connected photodiodes define a photometric, photoelectric transducer element. A capacitor is arranged to be charged and discharged in response to a photocurrent from the transducer element. The combination of the transducer element and the capacitor form a feedback circuit which is connected across the switching circuits to cause the latter to oscillate.

Abstract: A photometric circuit includes a differentiator arranged in cascade connection with an integrating circuit including an integrating capacitor which directly integrates a photocurrent produced by a photoelectric transducer element which is used for photometry. In this manner, a photocurrent output is derived from the integrated output from the integrating circuit.

Abstract: The disclosure is directed to an improved light measuring device which is used in flash photography for measuring a preliminary flash light to obtain camera exposure information for photography under a primary flash light. The device is so arranged as to preliminarily obtain informations of light amount contributing to photographing, with respect to each portion or area of a scene to be photographed or object field, in taking photographs with the employment of the auxiliary light.

Abstract: A number of light measuring elements are arranged at various portions of an image of an object focused by an objective. The light measuring elements are grouped for different zones to measure the average brightness of the image within the respective zones. The average brightness of the image is weighed and added together to calculate the brightness of the object based on which the exposure is controlled.

Abstract: An electronic circuit for sampling a digital pulse train signal and providing a replication in place thereof during a selected holding period includes a binary counter and register for counting and storing a clock pulse of substantially higher frequency than the sampled digital pulse train together with control gates for inhibiting the counter from rolling over in the event that the period of the sampled digital pulse train becomes so long that the maximum binary count capacity of the counter is reached. The sampled digital pulse train signal is preferably provided by the scene light detecting and integrating circuit of a photographic camera apparatus and the holding period during which the digital pulse train signal is substituted by the replicated signal corresponds to the flash fire duration of a strobe.

Abstract: A diaphragm control device of the type which performs TTL light measurement while stopping-down a diaphragm is constructed to automatically determine the diaphragm aperture by comparing an approximate signal with a reference signal to minimize the diaphragm aperture determination error caused when timewise variations are involved in the scene brightness. The approximate signal is generated by various circuits on the basis of a light measurement signal obtained by the TTL light measurement. The approximate signal varies approximately with the change in the diaphragm aperture due to the stopping-down operation of the diaphragm and coincides with the light measurement signal when no timewise variations are involved in the scene brightness.

Abstract: A photometer for use in combination with a camera determines the optimum film exposure interval with the exposure interval corrected for differences in illuminance between a subject of principal interest in the central portion of the scene to be photographed and the subjects of secondary interest in the foreground and background portions of the scene. The photometer includes a photo-responsive array divided into three light receiving segments each having a field of view that generally corresponds to, respectively, the central portion, the foreground portion, and the background portion of the scene.

Abstract: There is disclosed herein an electronic system and method for metering the incident light on a subject being photographed, some or all of which light emanates from an electronic flash unit, and for storing an incident light value for use in controlling the electronic flash unit during the taking of subsequent photographs of the subject. An exemplary system includes a remote light sensor which can be placed at or near the subject being photographed for measuring the light incident on the subject during a "test flash" from the electronic flash unit so as to enable the storage of an incident light value. This incident light value may comprise a signal representing the duration of the flash or a signal proportional to the drop in energy of the supply source of the electronic flash unit, both of which are proportional to the quantity of incident light.

Abstract: A camera includes a photographic film having a given film speed which decreases when the film is exposed to light which varies from a given illumination level. A camera shutter is controlled by a timing circuit adapted to produce an exposure which is adjusted to compensate for the decreased film speed.

Abstract: A control apparatus is disclosed for discriminating between light emitted from sources having respectively different flicker ratios (the ratio of the brightest and the dimmest intensities during a given time period). A photocell produces a voltage having a DC component proportional to the log of the average intensity of incident light and an AC component proportional to the log of the flicker ratio. After the DC component is removed, the AC component is amplified and may be applied to a filter-moving control means to cause appropriate color-correcting filters to be interposed between the scene and photosensitive material, as for instance in a camera. Alternatively, the AC component may control a marking mechanism to encode the film with a mark readable during the subsequent printing process.

Abstract: A quench strobe includes a light integrator circuit with an anticipation network which enables the quench to be anticipated by a predetermined time corresponding to the reaction time of the strobe quenching circuitry so as to avoid overexposure under conditions where the photographic subjects are close to the camera or under conditions of relatively high scene light reflectance.

Abstract: The disclosure is directed to an improved light measuring device which is used in flash photography for measuring a preliminary flash light to obtain camera exposure informations for photography under a primary flash light. The device is so arranged as to preliminarily obtain information of light amount contributing to photographing, with respect to each portion or area of a scene to be photographed or object field, in taking photographs with the employment of the auxiliary light.