Abstract: The invention contemplates dose-integrating instrumentation which relies upon continuously monitoring the illuminance level of a small sampling fraction of the total projected-light flux of the field-illuminating system of an operating microscope, the sampling being optionally within the projection system, or taken elsewhere. The sampled illuminance is in the form of an electrical signal which is continuously time-integrated to provide a continuous display of the dosage as it builds in the course of an operative procedure. Provision is made for the surgeon to preset what he chooses to be the safe upper limit of integrated exposure, beyond which he does not wish to go for fear of possible jeopardy to the retina of his patient, and the instrument continuously indicates the remaining time for him to complete his operation, should he continue at the current level of illumination.

Abstract: Light induced current from a photodiode is converted into a voltage proportional to the integral with respect to time of the current using two serially connected integrating operational amplifiers. In each case the integrating capacitors are connected so that the photodiode is part of the charge current for the capacitors. The amplifiers operate in sequence.

Abstract: The invention contemplates dose-integrating instrumentation which relies upon continuously monitoring the illuminance level of a small sampling fraction of the total projected-light flux of the field-illuminating system of an operating microscope, the sampling being optionally within the projection system, or taken elsewhere. The sampled illuminance is in the form of an electrical signal which is continuously time-integrated to provide a continuous display of the dosage as it builds in the course of an operative procedure. Provision is made for the surgeon to preset what he chooses to be the safe upper limit of integrated exposure, beyond which he does not wish to go for fear of possible jeopardy to the retina of his patient, and the instrument continuously indicates the remaining time for him to complete his operation, should he continue at the current level of illumination.

Abstract: An integrating photometer for measuring total exposures to ultraviolet radiation. The circuit for the photometer includes a threshold limiter to suppress operation of the integrator until the illumination level exceeds a predetermined threshold. A power saving circuit turns the photometer off when no illumination is received during a predetermined time interval.

Abstract: An improved light measuring device that is capable of measuring light upon initialization from either a flash of light or a manual switch is provided. A sensor assembly can produce a light intensity signal and a change in the intensity of the light measured can be used to produce a first signal. A second signal can be produced by a manually operable member. A counter can be used to count the number of signals and to produce a preparing signal upon an initial signal counted and a start signal upon a subsequent signal counted. Measurement of the amount of light in the circuit can be initially enabled when the counting means counts the first signal and the actual light measurement can be started subsequently upon the counting means initiating a start signal. Various sequences of producing the pair of signals can be utilized to control the operation of the light measuring device.

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 element which is provided with a pulse signal generator for generating pulse signals the duty ratio of which varies in accordance with a coefficient related to the exposure for photographing, a switching element which is driven by the output pulse signals from the pulse signal generator, and a light integrating circuit which includes a photo detector and an integrating capacitor and provides the voltage across the integrating capacitor as a light measure output. The light integrating circuit performs an intermittent light integrating operation by the action of the switching element. The integration period of the light integrating circuit is varied by varying the duty ratio of drive signals to the switching element which are supplied from a pulse signal generator, which duty ratio varies with a coefficient related to the proper exposure for photographing.

Abstract: An instrument for measuring laser energy in the visible range and which determines when the optical energy exceeds the accessible emission limit for a Class I laser. The instrument employs a photoelectric detector and a filter for a range of 476 to 633 nm. The instrument measures the optical energy as a function of time and compares the measured value with the accessible emission limit for a Class I laser at various critical points in time. A 3-digit engineering-notation display format is used to output the computed time at which the laser energy exceeds the Class I limit, as well as the total energy measured in 10 seconds. The instrument is adapted to measure either CW laser radiation, pulsed laser radiation, or each pulse of laser radiation, computes and applies a correction factor for optical error conditions or variations between optical detectors, and measures and compensates for background energy.

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: A solar energy flux integrator includes a semiconducting solar cell positioned to receive solar radiation, and a micro-coulombmeter connected to receive current from the solar cell. The micro-coulombmeter comprises a glass capillary filled with a mercury salt electrolyte having an indicating bubble and two mercury electrodes. A series resistor is provided which has a resistance value to slow the movement of the bubble when low levels of solar energy are incident on the cell so that movement of the bubble is directly proportional to the incident solar flux. This series resistor compensates for the spectral shift towards blue of the indirectly received solar radiation, which spectral shift otherwise causes the measured integrated value of solar flux to be too high due to the greater sensitivity of the solar cell to light of shorter wavelengths.

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: There is provided a photodetector wherein charging current to a photodiode is integrated to determine an amount of discharge due to conduction of photoelectric current through the photodiode and thereby to measure intensity of photon flux incident to the photodiode, so that linearity of light input intensity versus output voltage characteristics can be improved and dynamic range of the measurement can be extended.

Abstract: Apparatus for automatically detecting and measuring the energy of laser pes over a wide range of energy levels and in the presence of high ambient light levels. The current produced by a laser pulse striking a photoconductive detector is integrated by a capacitor to obtain a voltage across the capacitor which is proportional to the total energy incident on the detector during the pulse. The total energy of the pulse is then determined by measuring the time from when the capacitor voltage crosses a reference level during current integration to the time when the capacitor voltage, discharging through a resistor recrosses the reference voltage. The leading edge of the capacitor charging voltage is used to couple a high frequency oscillator to the input of a counter. The oscillator is then decoupled from the counter when the voltage of the discharging capacitor crosses a reference level. The count in the counter is transferred to a shift register for transmission to a data processing device.

Abstract: A light measuring device for use in photography and a method therefor is disclosed, in which the quantity of light during a time interval when the flash light is present is measured and also the quantity of light under the ambient light only is measured for obtaining various exposure information for photography using the flash light.

Abstract: A digital light measuring device capable of measuring a flash of light generated by a separate source device, irrespective of trigger modes of an electronic flash selected in advance, which comprises means responsive to an incident light intensity for producing an input commensurate thereto; means for processing an output to form a digital signal indicative of a result of the light measurement; means for detecting the beginning of change in the output of the producing means caused by a flashing to generate a start signal for making the processing means begin the processing operation; means for controlling the operations of the processing means in a programmed sequence, and, where necessary, means for directing the controlling means to start the programmed sequence when a code-trigger mode is selectively chosen for the trigger mode of the electronic flash.

Abstract: A method for detecting, monitoring or measuring visible and ultraviolet radiation exposure wherein a liquid crystal element covered with a coating layer transparent to the radiation is placed in the path of the radiation to be monitored and then the shift of the spectral reflectance or transmittance of the element is measured, this shift being a measure of the radiation dosage. This shift may be measured using reference liquid crystal elements or a spectrophotometer or similar measuring devices.

Abstract: The meter senses flashes of illumination, it converts the illumination to an electrical current whose magnitude is proportional to the intensity of the illumination; it integrates the current over a period of time corresponding to a selected shutter speed by charging a capacitor; it discharges the capacitor and measures the time required to do so; it converts the time required to discharge the capacitor into a corresponding signal representative of an appropriate camera aperture setting for a preselected film sensitivity and shutter speed via a microprocessor and a stored data program; and then displays the camera aperture setting on a multi-segment display. This process is repeated with each new flash of illumination automatically. The meter also measures multiple flashes and displays an accumulated camera aperture setting as well as the number of flashes needed to accumulate that setting.

Abstract: The invention provides a method and apparatus for measuring and recording the amount of solar energy falling at a place over a given period of time, comprising means for producing a frequency signal representative of the energy falling at the place, the provision of the frequency signal being controlled in response to the level of solar energy falling exceeding a morning threshold and falling below an evening threshold, and the frequency signal being applied to a counter, preferably fitted with print-out means, whereby the counter may record the total energy falling between the morning and evening thresholds.

Abstract: Effective shutter speed, focal plane exposure and film transport frame rate measurements are taken and displayed in user oriented format by a computing method and system for testing still and cinematic cameras. An analog signal pulse is generated that is responsive to the illuminance admitted to the camera focal plane during each camera shutter operation. Comparison of the analog signal pulse with various voltage threshold levels provides pulse period, overrange and underrange information. Cinematic frame rate is determined by dividing units by the time period, in seconds, between the beginnings of successive analog signal pulses; effective shutter speed is determined by dividing the peak amplitude value by the integrated value of the analog signal pulse; and focal plane exposure speed is determined by dividing the camera calibration constants by the integrated value of the analog signal pulse.

Abstract: Enzyme activity for a given sample is automatically determined by measuring light-extinction, at each of a succession of "points" in time and involving a plurality of measurements at each such time. At each of these "points" in time, the several individual measurements are made within a period of time which is brief as compared with the period of time between successive measurement points, and mean value and standard deviation are calculated from these individual measurements. A regression curve is drawn through the measurement points thus obtained, the enzyme activity being determined from the slope thereof at a predetermined time. A total measurement error is also calculated at the same time.

Abstract: This solar radiation measuring system records the integral of total solar radiation over a given period of time, and also records the periods during that time when the sun was obscured by clouds or other objects. The measurement of the integral of solar radiation includes all spectral components of the solar spectrum from the ultra-violet through the infrared. The design of the device is such that readout is simple and complex data reduction is unnecessary.

Abstract: A radiant energy integrating meter having one or more parallel connected reversed biased radiant energy sensor cells connected to an integrating circuit having an integrating capacitor. A trigger circuit having a differential amplifier, connected to the integrating capacitor, which drives a further amplifier, is adapted to close a first switch such as a silicon controlled rectifier in response to a predetermined integrated sensor current. A counter circuit is coupled to the first switch and advances by one each time the first switch is closed. A second switch such as a relay is coupled to the first switch to provide a discharge path for the integrating capacitor. Finally, a delay circuit is coupled across the first switch to open the first switch after a predetermined time delay.

Abstract: A long exposure photometer-digitizer operative in an integration mode to receive weak illumination as from celestial observations through a telescope or from field or laboratory observations of objects and to provide a recorded digital representation thereof. A silicon, vidicon illumination sensor is employed to provide a wide dynamic range, sensitive and linear response over a large spectral region. Cumulative photon interaction with the vidicon tube during a long exposure is achieved by operating the vidicon at a reduced temperature which minimizes dark current effects and promotes integration mode operation. After a predetermined vidicon exposure interval the image electrically stored in the target is read out by a scanning electron beam, digitized and recorded to provide an immediately available digital record of the object. The target is sensitized before each exposure.

Abstract: An electric exposure meter for storing the brightness of a photographic object as an electric voltage of a magnitude corresponding thereto in order to control the exposure time by using the voltage thus stored.

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.