Abstract: The invention concerns a differential-reflectance photometer for quantitatively evaluating test strips, especially for chemical analysis. The differential-reflectance photometer is characterized in that two optical channels are arranged in one housing in V-shaped fashion with each channel receiving an optical emitting and an optical receiving arrangement, that the channels enter a common space at the apex of the V, that a reference field associated with both emitting and receiving arrangement is provided on the bottom of the common space, that the emitting and receiving arrangements are connected to a common evaluation apparatus, and in that between the reference field and the emitting and receiving arrangements is a receiving slot, which intersects both channels, for receiving a test strip with two test fields each of which becomes associated with a respective one of the two channels.

Abstract: A device for measuring the shading of a translucent pane having an exterior side and an interior side comprising first and second photoelectric sensors for measuring unattenuated daylight, each of the sensors having a photosensitive surface and a spectral sensitivity substantially corresponding to the spectral sensitivity of the human eye and generating an output signal proportional to the intensity of the measured daylight, a first mounting element for mounting the first sensor on the exterior surface with the photosensitive surface of the first sensor facing away from the exterior surface, a second mounting element for mounting the second sensor on the interior surface with the photosensitive surface of the second sensor facing the interior surface, a housing, and an electronic circuit disposed in the housing and electrically connected to the first and second sensors for calculating the difference of the output signals of the first and second sensors, calculating the ratio of the difference to the signal fr

Abstract: A photometric device of the kind obtaining information on the luminance of each of photometric areas defined by dividing a photographing field at least into a middle area and a peripheral area and computing a photometric value on the basis of luminance information obtained from the middle and peripheral areas includes: detecting means for detecting whether the luminance information obtained from the peripheral area exceeds a given upper limit luminance level; and correcting means which is arranged to substitute a specific luminance information value for the luminance information obtained from the peripheral area when the latter is detected by the detecting means to be exceeding the upper limit luminance level.

Abstract: A contralight compensation exposure control system which determines as a contralight condition and fires a strobe when there is a difference between the output of a partial light measuring means for measuring the brightness of a portion of a scene to be photographed i.e. the brightness of the main object such as a person, and the output of an average light measuring means for measuring the brightness of comparatively large area of the scene i.e. the brightness of the subordinate object such as the background of the main object. The control circuit of the system inhibits the strobe firing and actuates an exposure compensation means to shift the controlled exposure to the overexposure side when a detecting means detect uncompletion of charging of the main capacitor for firing the strobe even if the contralight condition is detected.

Abstract: An apparatus for monitoring the light energy power level of a beam of light, includes beamsplitters on the axis of the light beam for directing portions of the light beam in first and second paths respectively orthogonal to the axis while transmitting the remaining portion of the light beam therethrough. First and second photodetectors having similar spectral responsivity intercept the first and second light beam portions respectively, and detect and signal the light energy power level of the respective first and second light beam portions. Analysis circuitry coupled to the first and second photodetectors and responsive to the output signals therefrom to calculate the total light energy power level of the light beam. The apparatus resolves linearly polarized light into two orthogonal components while permitting most of the light to exit. This exit beam can be analyzed in terms of the incident beam or monitored for measurement or control purposes.

Abstract: A light measuring device comprises light receiving means arranged to divide a photographing field at least into three areas including a middle area located in the middle of the field, a first outer area located on the outer side of the middle area and a second outer area located on the outer side of the first outer area and to obtain luminance information on each of the areas; luminance difference detecting means for obtaining information of a luminance difference between adjacent areas among the plurality of areas from a plurality of luminance information values obtained by the light receiving means; computing means including photometric value computing circuits equivalent to a plurality of computing formulas each of which including as a function at least one of the plurality of luminance information values obtained by the light receiving means; and selection means for selecting one of the photometric value computing circuits of the computing means which is equivalent to one of the computing formulas on the

Abstract: A projection aligner wherein light from a light source is passed through a mask so as to focus an image of a pattern of the mask on a wafer, characterized in that at least one sensor for monitoring a luminosity and a distribution thereof is disposed in an optical path between the light source and the mask, whereby a luminosity and a distribution thereof on the wafer can be controlled to proper values. The projection aligner is effective for application to minute processing technologies for the production of semiconductor devices, etc.

Abstract: A monitoring arrangement monitors the power of a light beam which travels in a predetermined path between a laser and a destination location and is reflected at a predetermined location of the path from a reflecting surface of a deflecting mirror, with attendant inherent light scattering into a space portion. The monitoring arrangement includes at least one sensor situated in a space portion having the reflecting surface and imaginary extensions thereof for its boundary and including the predetermined path. The sensor is located between a reflected portion of the light beam and the boundary, preferably close to the boundary, to intercept and sense scattered light reaching it, especially forward-scattered light of the original laser beam, and generates a signal representative of the intensity of such intercepted scattered light. This signal is then evaluated.

Abstract: An optical power meter system comprises a chopper with a semicircular total reflection mirror along an incident light path, two photo-detectors of different characteristics of wavelength sensitivity, and a comparator for comparing the levels of the photo-detection signals derived from the two photo-detectors and for outputting the optical detection signal of a higher level. The photo-detectors are positioned in a first path of the light passing through the chopper and a second path of the light reflected by the chopper, respectively. The comparator may be replaced by an adder for adding the photo-detection signals derived from the two photo-detectors.

Abstract: The present invention is characterized by repeatedly AD converting in a time series an output of each light sensitive element, and at the same time an added value or a mean value of each one of said AD converted values is obtained so that such added value or a mean value is used as an output of each light sensitive element. According to the present invention, an influence of flickering of an artificial light source can be eliminated and at the same time a light measuring computation with a high level of accuracy can be made with a higher speed than that in a conventional method, and particularly in a light measuring apparatus housing a number of light sensitive elements a light measuring computation with a high level of accuracy can be made in a by far faster speed than that in a conventional method.

Abstract: Methods and apparatus for all-optical analog to digital conversion. An analog optical input signal is directed along a path comprising a series of level sensing means for determining whether its intensity is above or below a threshold value. The optical signals from successive level sensing means are directed in pairs to optical exclusive-or gates to provide a digital optical signal to at least one of a plurality of individual optical output means according to a designated digital coding system whereby the optical digital indication corresponds to the sensed level of intensity of the analog optical input signal. Apparatus comprising channel waveguides and integrated optical devices provide economical systems for high-speed computation and other uses.

Abstract: A photometrical apparatus has a first light receiving element, and a second light receiving element less sensitive to temperature and other environmental influences than said first light receiving element whereby a value Pm of measured quantity of light from the subject is calculated from the following formula ##EQU1## Pr designates a quantity of light from a standard light source, Dr and Dm designate outputs of the first light receiving element generated by the light from the standard light source and the subject, Dpo and Dpt designate outputs of the first light receiving element generated by the light from the reference light source and the subject, and Dso and Dst designate outputs of the second light receiving element generated by the light from the reference light source and the subject.

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: A projection aligner wherein light from a light source is passed through a mask so as to focus an image of a pattern of the mask on a wafer, characterized in that at least one sensor for monitoring a luminosity and a distribution thereof is disposed in an optical path between the light source and the mask, whereby a luminosity and a distribution thereof on the wafer can be controlled to proper values. The projection aligner is effective for application to minute processing technologies for the production of semiconductor devices, etc.

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 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 system for measuring laser pulse durations in the range of ten nanoseconds to one femtosecond to an accuracy of one femtosecond, includes a primary pulse sampler, a ten component beam splitter array, optical delay lines whose settings are microprocessor controlled, a ten section interaction chamber with ten sets of ion detectors and a pulse envelope and pulse energy display monitors. The system has applications in chemistry, calibration of fast timing circuits and in the development of short pulse lasers.

Abstract: An apparatus and method for measuring solar radiation received in a vegetative canopy. A multiplicity of sensors selectively generates electrical signals in response to impinging photosynthetically active radiation in sunlight. Each sensor is attached to a plant within the canopy and is electrically connected to a separate port in a junction box having a multiplicity of ports. Each port is connected to an operational amplifier. Each amplifier amplifies the signals generated by the sensors. Each amplifier is connected to an analog-to-digital convertor which digitizes each signal. A computer is connected to the convertors and accumulates and stores solar radiation data. A data output device such as a printer is connected to the computer and displays the data.

Abstract: A rear light condition detecting device for a camera is arranged to measure distances to a plurality of parts appearing within a taking picture plane on the assumption that an object located nearby is the main object to be photographed or that a light source such as the sun is among faraway objects. The device determines the object to be in a rear-light or counter-light condition in cases where the luminance of the nearby object is extremely lower than other objects or that of a faraway object is extremely higher than other objects.

Abstract: A color information detecting device comprising a plurality of color detecting apparatus for detecting respective different color lights from each other, converting apparatus for producing an output in non-linear relation to the input signal, changeover apparatus for selectively applying the outputs of the color detecting apparatus to the converting apparatus, apparatus for coinciding a number of successive outputs of the converting apparatus, and computing apparatus for computing the coincided signals from the coincidence apparatus. The device also includes a first constant current source for applying current of a prescribed intensity and a second constant current source for supplying current of another intensity equal to the prescribed intensity times the intensity of the current supplied from the first source which are included so that another mode can operate. The outputs of the first and second constant current sources are selectively applied to the converting apparatus.

Abstract: An atmospheric contrast transmittance monitor is described which comprises an electro-optical system including three solid state transducer assemblies interfaced with a small dedicated microprocessor for control of the system in either semi-automatic or operator interactive modes for real-time monitoring of the optical state of the atmosphere, one assembly comprising a compact multi-channel nephelometer of novel configuration for providing directional volume scattering function measurements on atmospheric samples, and a pair of staring fisheye lens scanners and associated detectors for scanning the upper and lower hemisphere radiance distributions. The system requires only a few hundred watts of input power and is less than one meter in length overall, and, operating in pulsed mode, has been used to measure the scattering characteristics of clear-day room air, with adequate sensitivity to suggest the capability of measurements approaching 10.sup.-5 m.sup.-1, i.e., sea level molecular.

Abstract: Six silicon solar cells are arranged in three pairs on three mutually perpendicular planes. One cell of each pair will be exposed to both the direct rays of the sun and the diffuse light radiation incident from the same direction, depending upon the orientation of the device and the time of day. The other cells of each pair will be exposed only to the diffuse radiation on their respective planes. The differences in the measured radiation on each plane are squared, summed, and the square root of the sum then taken to determine the actual value of the direct rays of the sun.

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 device for measuring light incident on an optical system comprises an optical system defining an optical path, a plurality of diffraction lattices arranged in the optical path, each of the diffraction lattices comprising a plurality of periodically arranged semireflecting oblique surfaces, and photodetector means for detecting each of the diffracted lights from the diffraction lattices distinctively. The diffraction lattices are each of different predetermined areas; however, when even light is input, each lattice diffracts the same total quantity of light to its respective detector.

Abstract: A lighting control system is provided which utilizes a light responsive sensor means and a control system to respond to the skylight illumination while rejecting direct sunlight as a control parameter. The skylight illumination level is used to control lighting power controllers that can dim interior lighting equipment in a defined pattern to maintain a uniform light level at a work surface and to conserve electrical energy.

Abstract: An analyzer compensation circuit for compensating for the fluctuations in the intensity of the light source or for stains on the windows of cells in an analyzer. A pair of D-A converters are respectively connected to compensating and measuring light detectors. An up/down counter is arranged to count either up or down in response to the output of a comparator. The comparator compares the output of the D-A converter connected to the compensating detector with a reference value and the output of the up/down counter is connected to both of the D-A converters such that the output of the converter connected to the compensating detector is adjusted to be equal to the reference value. Since the other D-A converter is also connected to the output of the up/down counter, the output of the other D-A converter has been compensated for fluctuations in the light intensity or stains on the windows on cells used in the analyzer.

Abstract: A visible spectrum radiation measuring apparatus achieving an absolute measurement utilizing a plurality of inversion layer silicon photodiodes in a configuration wherein light reflected from the surface of a photodiode impinges on another photodiode, and its respective reflected light impinges on another photodiode, such that each time the light impinges on a photodiode surface a portion is absorbed, and that ultimately most of the light of the beam being measured is absorbed.

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: A method for determining the optimum time at which a plasma etching operation should be terminated. The optical emission intensity (S.sub.1) of the plasma in a narrow band centered about a predetermined spectral line, indicative of the gas phase concentration of a plasma etch product or reactant species. The optical emission intensity (S.sub.2) of the plasma in a wide band centered about the predetermined spectral line, indicative of a background emission signal is also monitored. The intensity (S.sub.1L) of the spectral line is then determined in accordance with the equation S.sub.1L =S.sub.1 -k (.alpha.S.sub.2 -S.sub.1). The etching process is terminated when the monitored signal intensity (S.sub.1L) or its time derivative reaches a predetermined value.

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: According to the invention, a thin wire 13 is arranged across the laser beam 2, and the change of resistance in the thin wire 13 is measured by a resistance meter 21 while moving the thin wire 13 by a driving mechanism 23, thereby to measure the power of the laser beam or the position of the laser beam. The apparatus can be used for monitoring the power of laser beam or position of the same used in the high-power laser device for processing or the like purpose. According to the invention, it is possible to monitor the power and position of the laser without interrupting the laser beam and without incurring substantial increase of the loss of power of the laser beam.

Abstract: A light measuring device includes one or more photodiodes, which generate current in relation to the received light, and at least one capacitor for integrating the generated current. The amount of charge stored in the at least one capacitor at the completion of the integration is roughly detected by the number of capacitors used and/or the voltage across the capacitor. A current source capable of producing different levels of current in accordance with the detected amount of charge is provided for changing the amount of charge stored in the at least one capacitor. The time needed to change the amount of charge stored in the at least one capacitor is measured so as to obtain the value of total amount of the change in the charge stored in the at least one capacitor and to thus obtain the value of the received amount of light intensity.

Abstract: A simplified multi-light measuring device in a photographic system capable of measuring an object field divided into plural areas. The device comprises register means (e.g. 100-500) comprising plural registers for storing plural photoelectric output signals from the plural areas as digital data; reference output generating means (e.g. 60) for generating a reference output signal for determining digital data to be stored in the register means; comparator means (e.g. 21-25) for comparing each of the plural photoelectric output signals with the reference output signal and providing a corresponding output signal; and retaining means for retaining, in response to the output signal from the comparator means, digital data stored in a corresponding register of the register means.

Abstract: In a camera or a printer, exposure is controlled based on a selected mode of a light measuring system which has two modes of weighting the light measurement in for differently weighting various parts of an image of a scene according to whether the image is of a back light scene or a normal light scene. The light measuring means determines whether or not the difference in brightness between the central part and the marginal part of the image of a scene is smaller than a predetermined value. Pursuant to such determination, one of the modes of the light measuring system is selected, and the exposure is controlled by the output of the light measuring system in the selected mode.

Abstract: A method and apparatus for converting the intensity of an unknown optical signal (B) into an electrical signal in digital form utilizes two elongated optical attenuators (11, 13), one for the unknown optical signal from a source (10) and one for a known optical signal (A) from a variable source (12), a plurality of photodetectors (e.g., 17, 18) along each attenuator for detecting the intensity of the optical signals, and a plurality of comparators (e.g., 21) connected to the photodetectors in pairs to determine at what points being compared the attenuated known signal equals the attenuated unknown signal. The intensity of the unknown relative to the known is thus determined by the output of a particular comparator. That output is automatically encoded to a relative intensity value in digital form through a balancing feedback control (24) and encoder (23).

Abstract: The invention concerns an opto-electrical device for measuring the orientation and the characteristic luminous intensities of light beams.The device is essentially characterized by containing at least: a screen on which photo-electric transducers are situated, a positioning device for the screen according to a reference direction, amplifiers and voltage dividers which give signals proportional to the characteristic luminous intensities sensed by the transducers and comparators for comparing the ratios between the voltage and between the maxima of sub-sets of voltages.

Abstract: A metering device for metering an object field by dividing it into a plurality of areas and producing a plurality of metering outputs corresponding to the brightnesses of said areas includes means for extracting from the plurality of metering outputs a plurality of reference outputs different in level from one another, means for evaluating the level of at least one of the reference outputs, and means responsive to the evaluating means to select and put out one of the reference outputs.

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: 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: An apparatus is described which provides a numerical indication of the cloudiness at a particular time of a day. The apparatus includes a frame (18) holding several light sensors such as photovoltaic cells, with a direct sensor (12) mounted to directly face the sun and indirect sensors (13-16) mounted to face different portions of the sky not containing the sun. A light shield (30) shields the direct sensor from most of the sky except a small portion containing the sun, and also shields each of the indirect sensors from direct sunlight. The relative values of the outputs from the direct and indirect sensors, enables the generation of a numerical indication (56) of the degree of cloudiness at a particular time of day.

Abstract: An improved light intensity measuring device includes a temperature compensating logarithmic amplifier that changes photodetector currents which have been converted from AC to DC to a voltage which drives an analog to digital converter. The resulting digital signals are displayed. For differential or absolute measurements, a second, identical, logarithmic amplifier channel is employed and both are coupled to a differential amplifier. A standard reference current applied to one channel provides an "absolute" measurement of the signal applied to the other channel or a second signal may be compared to the first.

Abstract: A multispectrum light detection system for controlling exposure time of a photoresist coated substrate in a projection aligner-printer machine wherein the relatively narrow spectral responsivity characteristics of a selected photoresist is matched to the wider spectrum inherent in the output flux of a combined light source and optical system. A representative sample of the system's wide spectrum output flux is divided into three or more narrower spectral bands each of which is measured by its own detector that provides an electrical signal proportional to the radiant flux intensity within that band. The resultant electrical signals from the separate spectral bands are weighted and combined in a summing amplifier to form a composite exposure control signal. Means are provided to adjust the contribution of each electrical signal to the combined control signal in accordance with known spectral response characteristics of the photoresist.

Abstract: An automatic analytical apparatus which comprises a single reaction line and in which reaction vessels are carried step by step along the reaction line, a sample and reagent are delivered to the reaction vessel during each carrying step to obtain a test liquid, and the test liquid thus obtained is subjected to a photometric operation, characterized by comprising (a) sample and reagent delivering means for delivering the sample and reagent into a plurality of reaction vessels in succession, respectively, during each carrying step of the reaction vessel, and (b) means for subjecting the photometric operation to a plurality of test liquids at separate positions at the same time during each carrying step of the reaction vessel.

Abstract: An exposure indicating device indicates at the same time a result of average light measurement which measures a light level of a substantial portion of a scene to be photographed, and a result of spot light measurement which measures a brightness at a small portion of the scene. One of the values of the average and spot light measurements is displayed numerically to indicate its absolute value, while the other is displayed as a deviation from the former value.

Abstract: Disclosed is a solid state wavelength detection system responding to output signals derived from a photoelectric semiconductor device. The photoelectric semiconductor device comprise at least two PN junctions formed at different depth from the surface of the semiconductor substrate. A deeper PN junction develops an output signal related to longer wavelength component of the light impinging thereon. A shallower PN junction develops an output signal related to shorter wavelength component of the impinging light. These two output signals are logarithmically compressed and compared with each other. Difference of the logarithmically compressed output signals represents the wavelength information of the impinging light.

Abstract: An exposure display device for a camera including a metering device for effecting metering while dividing a phototaking picture plane into a plurality of areas and for emitting a plurality of photoelectric conversion signals corresponding to those areas and processing circuitry for operating and emitting a proper exposure signal from the output signals of the metering device comprises comparing circuitry for comparing the plurality of photoelectric conversion signals with the proper exposure signal and emitting the result of the comparison, and a display device for displaying the comparison results emitted by the comparing circuitry while causing the comparison result to correspond to the divided areas.

Abstract: Apparatus for measuring progressively the absorbance changes of a large number of aliquots from a plurality of different samples. The sample introduction, testing instructions, aliquot preparation, reagent dispensing, absorbance measuring and data recording all can be accomplished in a continuous mode of processing. Stat and batch operation also can be accomplished. The aliquots are in an array of cuvettes which is advanced slowly along a circular path. Photometer means, preferably having several photometric detectors, are mounted in fixed orientation on a common support that advances rapidly along a similar circular path, such that radiation passing through each of the cuvettes is monitored many times by a specific photometric detector by the time that cuvette completes one circuit of its path. The photometric detectors can operate at several different wavelengths. Many different chemical reactions can be monitored at the same time.

Abstract: The present invention relates to a system for exposure measurement and/or focus detection by means of image senser such as photo diode array (MOS image senser), CCD (charge coupled devices) consisting of a plural number of adjacently disposed respectively integrated fine light sensing elements whereby the image pattern of the object is scanned purely electrically in such a manner that the then obtained output of each light sensing element is converted into a digital value one after another for processing.

Abstract: An improved exposure control apparatus for camera comprises a metering circuit, exposure operational circuit, correction value calculating circuit and correction operational circuit. The metering circuit meters a plural number of divisional sections of the field of an object and generates a plural number of photoelectric outputs corresponding to the respective sections of the field. The exposure operational circuit calculates an exposure value from the plural number of photoelectric outputs. The correction value calculating circuit calculates correction values for correcting the distribution characteristics of said photometric outputs relative to the distribution characteristics of illumination on the focal plane of the photographing lens of the camera at the time of photographing, the correction values corresponding to the sections of the field respectively.

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.