Abstract: The invention relates to a simple and relatively inexpensive way of determining the optical bit rate of an optical signal, which is based on the fact that different percentages of the signal will be transmitted through a narrow-band optical filter depending on the bit rate. Increasing the bit rate of an optical signal results in a broadening of the channel spectrum, therefore, if the optical filter is designed with a passband thinner than all (or all but one) of the channel widths, then signals with different bit rates will have distinctive amounts of transmitted light relative to the amount of input light. In the preferred embodiment the optical signal is divided into two sub-beams by a beam splitter, and one of the sub-beams is passed through the optical filter. The power of filtered sub-beam is compared to the power of the unfiltered sub-beam to provide a ratio, which is compared to one or more predetermined values indicative of the bit rate.

Abstract: A flare measuring method and a flare measuring apparatus for measuring flaring occurring on optical systems, an exposure method and an exposure apparatus, and an exposure apparatus adjusting method capable of quantitatively measuring information regarding flare which occur on optical systems are to be provided. A flare measuring apparatus S for measuring flare which occur on optical system IL is provided with a light source device for irradiating an optical path including the optical system IL with an exposure light EL, a substrate M1 arranged on the optical path and provided with predetermined patterns C and T, a detecting device DT arranged on the image plane of a projecting optical system PL and capable of detecting information on the luminous energy of the light, and a control device CONT capable of controlling the irradiating range of the exposure light EL and acquiring information on flare on the basis of the result of detection of the exposure light EL by the detecting device DT.

Abstract: To provide a thin film forming method and apparatus that can automatically form thin films having constant optical properties with high reproducibility Antireflection films are deposited on lenses 2a that are held by a coating dome 2 by vaporizing an evaporation material 4 by using an electron gun 3 The power to be applied to the electron gun 3 is controlled so that a transmission or reflection light quantity value that is measured at each time point by an optical film thickness meter 10 becomes equal or approximately equal to a standard light quantity value stored in a standard light quantity value data storing means

Abstract: A light measuring apparatus is provided with a photoelectric conversion element for converting a light energy to an electrical signal, a calculation circuit for calculating a measurement value based on the electrical signal, a memory for storing a correction value, a corrector for correcting the measurement value using the correction value, and a controller for allowing calculation of a recent correction value when the timer measures elapse of a predetermined time, and permitting the memory to renewably store the recent correction value.

Abstract: To provide a thin film forming method and apparatus that can automatically form thin films having constant optical properties with high reproducibility. Antireflection films are deposited on lenses 2a that are held by a coating dome 2 by vaporizing an evaporation material 4 by using an electron gun 3. The power to be applied to the electron gun 3 is controlled so that a transmission or reflection light quantity value that is measured at each time point by an optical film thickness meter 10 becomes equal or approximately equal to a standard light quantity value stored in a standard light quantity value data storing device.

Abstract: The invention concerns a method and device for automatic cleaning of opto-electronic measuring systems used in process-technology for the analysis of substances in liquids and gases by means of optical absorption and fluorescence. The method is characterized in that the soiling degree is detected by the opto-electronic sensor system itself and, with predetermined soiling degree, a cleaning liquid cleans the soiling-sensitive optical components and detects the residual soiling, which is then evaluated quantitatively and compensated for in the signal analysis.

Abstract: In a method for monitoring the measurement light emitted from an illumination apparatus for an optical measuring instrument, a continuous sensing of measurement light parameters is performed. The sensed measurement light parameters are compared to predefined setpoints. Any deviation from the predefined parameter ranges associated with the setpoints is signaled. This signal is used to initiate a lamp exchange on the illumination apparatus, which has multiple lamps that can be selectively switched on and off individually or in groups. Also described is a corresponding illumination apparatus that preferably performs a lamp exchange automatically. The result is to identify a point in time for a lamp change that is optimal with regard to measurement accuracy and the longest possible utilization of the lamps, so that a measurement light quality that remains consistent during continuous operation can reliably be maintained within predefined tolerance ranges.

Abstract: A semiconductor device manufacturing method includes the steps of providing a projection exposure apparatus, exposing a wafer by using the projection exposure apparatus, the exposing step including projecting a circuit pattern onto the wafer through the projection optical system using light from a first laser, and developing the exposed wafer. Before the providing step, an optical performance of the projection optical system is measured by producing an interference fringe, bearing information related to aberration of the projection optical system, by use of a harmonic of a second laser having a coherency higher than that of the first laser, and then by analyzing the interference fringe. A wavelength of the light from the first laser is registered with that of the harmonic of the second laser.

Abstract: An external calibration system for a photo multiplier tube is described. The calibration system uses a light emitting diode and a photo cell wherein the diode is domed shaped. The light sensitive face of the photo multiplier tube is contained in the plane disposed at an acute angle to the longitudinal axis of the light emitting diode, and the photo cell is mounted substantially perpendicular to the longitudinal axis. A source of electrical energy then illuminates the light emitting diode over a range from, for example, 0 to 5 volts to generate light of known intensity and the light being generated is simultaneously measured by the photo cell and the light sensitive face of the photo multiplier tube. A feedback circuit is provided and associated circuitry so that a number of readings can be taken over a wide variety of light intensities to generate a calibration for the photo multiplier tube.

Abstract: When a vehicle enters into the lower portion of a shielding member, a headlamp is switched on, and a condition flag is set to Set 1 which represents a waiting state in which the vehicle exterior is estimated to become bright/dark intermittently. When the condition flag is set to Set 1, when the vehicle enters into the lower portion of the shielding member, the condition flag is set from Set 1 to Set 2 which represents an intermittent state in which the vehicle exterior becomes bright/dark intermittently with high possibilities. When the condition flag is set to Set 2, a switch-off extension time CFE and a switch-off delay time CTF make a time until the headlamp is switched off. As a result, the time until the headlamp is switched off is delayed, and the headlamp is required to remain switched on at portions where the vehicle exterior becomes bright/dark intermittently.

Abstract: Apparatus are disclosed that are operable to changes the intensity, per unit surface area, of an irradiation laser light flux. A typical apparatus comprises, on an optical axis, an irradiation laser light source, a stop defining an aperture, and an optical subsystem situated between the light source and the stop. The optical subsystem is operable to change the intensity of the irradiation laser light flux passing through the aperture by changing the diameter of the beam of irradiation laser light flux incident on the stop.

Abstract: An arrangement for inspecting the surface of a rotating object (1) which includes object retaining means for retaining whilst rotating the object, means (3) for irradiating the surface of an object when retained and rotated by the object retaining means with a first beam of optical radiation, means (5) for irradiating the surface of an object when retained and rotated by the object retaining means with a second beam of optical radiation detectable as distinct from the first beam, detector means (7) for detecting radiation reflected by the surface of the object from the first beam and for detecting radiation reflected by the surface of the object from the second beam and a signal processor (15) for receiving signals produced by the detector means and for analysing such signals wherein the first beam and the second beam are of different wavelengths or in different wavelength bands and the detector means is capable of simultaneously receiving and detecting radiation received from the same irradiated area of the

Abstract: The invention relates to a device for detecting a wetting of a pane having a wetting sensor which is provided with a measuring circuit having a transmitter, which emits light, and a receiver, which responds to the emitted light and emits a sensor signal, as well as with an evaluation device for the sensor signal comprising a difference former.

Abstract: An energy beam threat discrimination system (110) adapted for use with laser beam energy (134). The system (110) includes an first detector (114) for detecting a first laser signal. A second detector (112) detects a coherent laser signal. A timer circuit (124, 126) establishes a time interval between the detection of the first laser signal and the detection of the coherent laser signal and provides an output (130) in response thereto. A control circuit (128, 130) determines, based on the output (130), if the first laser signal and/or the second laser signal is threatening. In a specific embodiment, the first detector (114) provides an event detection flag (118) as an output in response to the detection of a first laser signal. The first detector (114) includes a high sensitivity laser light detector (142), a pre-amplifier (144), and an analog threshold circuit (146). The coherent detector (112) provides a coherent detection flag (116) as an output in response to the detection of the coherent laser signal.

Abstract: A mean optical power controller that controls power using a voltage controlled optical attenuator (VCOA) is disclosed. This controller uses a control loop in which a signal indicative of the present optical power level is compared to a signal indicative of the desired optical power level, with the difference then being used as input into the VCOA. This controller generates the required variety of signals indicative of the desired optical power level, or reference signals, without having to rely on a CPU. It does this by storing in a local storage means the voltage-values of the reference signals required to realize each supported user-defined optical power level. During the operation of the controller, the voltage-value corresponding to each selected power-level is passed to one or more DACs, where it is converted into a reference signal.

Abstract: An instrument and method for optically calibrating and balancing low level luminances of lighted instrument panel displays within the operator station of a vehicle is described which comprises a self-contained, calibrated luminance source and a beamsplitter for combining and juxtaposing an image of the calibrated luminance source with an image of the luminance from a lighted instrument panel display to be calibrated or balanced, whereby the images may be compared in luminance, the lighted instrument panel display being adjustable in intensity using the vehicle instrument panel light trim capability.

Abstract: An apparatus and method for processing a time domain reflectometry (TDR) signal to generate an output result corresponding to a valid process variable. The method includes the steps of processing the TDR signal using at least two different techniques for detecting a valid reflection pulse generated by the process variable to calculate an independent result using each of the at least two techniques, and applying a weighted factor to the independent results from each of the at least two different techniques to provide weighted output results. The method also includes the steps of comparing the weighted output results, and selecting the valid output result from the weighted output results based on the comparing step. In the illustrated method, the comparing step includes the step of summing the weighted factors for each independent result.

Abstract: A method and an apparatus for compensating illuminance error of a light source is adapted to be used in a transmission type scanner and utilizes the light signal directly transmitted from the light source to an image pickup device of the scanner without passing through any scanned object as an illuminance calibration reference to compensating illuminance error of the light source. The calibration light signal can be transmitted from the light source to the image pickup device through a light transmission region arranged beside a scanning region.

Abstract: A light sensing device including at least one light sensor is provided. The at least one light sensor is configured to be exposed to a light image. In response to the light image, the at least one light sensor is configured to generate a first signal. The light sensing device further includes a measuring device coupled to the at least one light sensor. The light sensing device also includes a sampling generator configured to generate a sampling signal to the measuring device. The sampling signal is inhibited when the first signal is lesser than or equal to a predetermined value. Upon inhibition of the sampling signal, the measuring device retains a measure of the first signal.

Abstract: A voltage detecting circuit is capable of detecting the voltage to be detected at high precision, is small in size, and is low in manufacturing cost. A first photo coupler and a second photo coupler are interposed between voltage input terminals to which the voltage to be detected is applied. The photo coupler has light emitting elements connected parallel reversely, first voltage generator for generating a voltage depending on the photo detector side currents of the first photo coupler and second photo coupler, a differential amplifier whose one input terminal receives the voltage generated by the first voltage generator. A third photo coupler and a fourth photo coupler having light emitting elements are connected parallel reversely for receiving the output current of the differential amplifier, and a second voltage generator for generating a voltage corresponding to the photo detector side currents of the third photo coupler and fourth photo coupler.

Abstract: A calibration system for a measuring device utilizing a photo multiplier tube is provided. The calibration system is intended to provide a stable light source variable over a wide range of intensities which can be used to calibrate the PMT reading using a closed loop feedback circuit. The LED and a photo cell are disposed in a reference block chamber whereby the photo cell is in close proximity disposed perpendicular to the axis of the LED. The LED being dome shaped will direct light energy on to the photo cell, and also peripherally. The PMT is disposed adjacent the LED and at an angle to its longitudinal axis whereby light generated by the PMT simultaneously strikes both the photo cell and the PMT without reflection.

Abstract: A multi-purpose on-line or field-portable system and method for monitoring the presence and concentration of selected antigen-antibody reactions singly or in combination that result from the presence of specific microorganisms or free antigens present or suspended in aqueous solutions, during a given time period. The detection system comprises a detection column and two sensors mounted around the detection column. Each sensor consists of an electromagnetic radiation source and an appropriate detector for the electromagnetic radiation. The reacted analyte tends to accumulate at the sensor located at the bottom detection column. The lower sensor continually nulls against the upper sensor to subtract any optical effects due to non-reactants in the aqueous process or environmental stream. The response from the detector sensors drive an electric circuit, which provides an output signal. In the on-line automatic version, the signal can drive elements of a process system by switching automated valves.

Abstract: A method and apparatus for determining the quality of an illuminating device, such as an elongated lamp, that is useable with an imaging device, such as a scanner. Electrical power is supplied to the lamp so that it emits a light beam. The light beam is then measured and a determination is made as to whether the emitted light of the lamp is within one or more predetermined values, which include overall brightness, stabilized output power, and profile flatness values.

Abstract: The invention relates to a multichannel spectrometer (10), in particular for examining moles (16) having an evaluating and display device (14) and optical means (18, 19, 21, 23, 22) to determine and display reflectance spectra of a skin surface on an ascertainable image plane (x,y) while considering white standards (17).

Abstract: Titration apparatus includes two cells that receive and contain liquids and are transparent to light. A liquid having an unknown characteristic and mixed with an indicator that is optically responsive to a titrant is disposed in the cells. Light is transmitted through each cell to separate photosensors. The photosensor signals are compared and a titrant is added to one of the cells in known-volume increments until the difference between the signals reaches or exceeds a prescribed threshold. The characteristic of the liquid is calculated from the quality of known concentration titrant added in order to reach or exceed the prescribed threshold.

Abstract: A photographic method of collecting and reducing photographic film density data for monitoring air quality is disclosed in which photographic film is first calibrated using calibration scales of known reflectance and the measured radiance of one calibration scale step to relate the photographic film density to the known radiance. Measurement of a target's radiance and sight path radiance is made via target photographic image density analysis and mathematical expressions which convert density information into radiance and/or atmospheric transmittance data using expressions developed from the calibration scale data.

Abstract: A light measuring device calculates and displays a proper exposure condition even when the combination of shutter speed and aperture is predetermined by using a flashlight component and a measured light data.

Abstract: The disclosure is directed to a detecting arrangement for detecting presence or absence of an item to be transported, for example, a paper sheet or the like, which includes a light emitting element and a light receiving element disposed to confront a transport passage as a sensor for detection of the item to be transported along the passage. The detecting arrangement is characterized in that there are further provided a comparing circuit for comparing a signal responding to an output of the sensor with an integrated signal from an integrating circuit of an output of the sensor, thereby to employ a signal based on the result of the comparison as a signal indicating presence or absence of the item to be transported.

Abstract: A method and apparatus for converting radiant energy levels to digital data wherein an image sensor is provided having at least one row of sensor elements each including a light sensitive capacitor and an access switch and which changes state produces a corresponding binary output signal when a predetermined charge threshold is exceeded by the capacitor whose charge is a function of intensity and period of an illumination. The row of elements is first calibrated by illuminating same with a reference light source and sensing at a first frequency (F) such that approximately one half of the elements change state and counting the digital output signals corresponding to the changes of state to obtain a first number (B). Thereafter, the row is illuminated with an unknown light source which has a lower radiant energy level than that of the reference light source and senses at a frequency F/2. The digital output signals corresponding to the changes of state are counted to obtain a second number (A).

Abstract: Apparatus for controlling output signals from two light detectors in a photometer. The sensitivities of the light detectors, or the gains in amplifiers for amplifying output signals from the light detectors are controlled in such a manner that the sensitivity characteristics and output characteristics of the two light detectors are in agreement with one another, to thereby improve the measuring accuracy thereof.

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 system and apparatus for providing a measure of ESI (equivalent sphere illumination) as a function of Lb (background luminance) and Lt (task luminance) and in which a pair of envelopes are provided each having a varying transmittance such that one envelope can provide an indication of the term (Lb-Lt) and the other an indication of Lb whereby ESI can be determined.

Abstract: A beam from a test image is split into two paths. The beam in one path may pass through broad-band or narrow-band attenuators to the intensifier being tested. A portion of the beam in the other path passes through a hole in a reflector to the eye of a viewer. The intensifier provides an output beam, and this beam is reflected by the reflector to the eye of the view. The viewer thus sees an image that may have a lighter or darker portion, depending on whether the output beam from the intensifier is brighter or dimmer than the test image. Various attenuators may be inserted in the one optical path to provide tests of such things as intensifier gain, relative gain, or EBI on a go/no go basis.

Abstract: The measurement of equivalent sphere illumination on a given task located in a lighted area is disclosed herein. This is accomplished by comparing a movably mounted task in the lighted area with the same task in a control area illuminated with sphere illumination. The task is viewed alternatively in the two areas in accordance with specific optical procedures to determine the equivalent sphere illumination on the task in the lighted area.

Abstract: Apparatus for measuring the optical density of a sample includes a dual beam spectrophotometer producing sample and reference signals which are compared with the discharge curve of a resistive-capacitive circuit to provide start-stop signals, the time interval between the two signals being indicative of optical density. Embodied within this linearization means is a novel method of correcting for nonlinearities due to stray light. The start and stop signals are used to drive a linear ramp generator, the stop signal terminating the ramp at an analog signal level indicative of optical density.

Abstract: For determining the standard visual range by determining the relation between a measured signal and a reference signal, the two signals are processed purely electronically by amplifying one of the signals in an amplifier having a digitally programmed amplification factor controlled by a digital value representing the computed range, forming a quotient between the output of the amplifier and the other of the signals, employing the resulting quotient value to adjust the amplifier amplification factor to a value representative of the standard visual range, and providing a digital output corresponding to the amplification factor.

Abstract: An alternating light photometer, the output of which is connected over two parallel uniform current paths with both of the inputs to a differential amplifier. In each of the paths, there is included in series a resistance, a condenser, with a switch provided as well as between a switch and corresponding input of the differential amplifier, and an operational amplifier, all forming a storage circuit. The R C circuit forms a low pass with a time constant over the given engaging or disengaging time of the beam. The switches are so controlled over the switching circuit that only one of them is closed during the time of the complete release, and the other only during the time of the complete interruption of the beam to the photoelectric transducer.

Abstract: The two-beam photometer is suitable for extinction measurement on weakly-absorbent samples. The principle of measurement is based on a wavelength selection in either the comparison beam and the measuring beam. In the beam configuration measuring and comparison beam are coincident in space and follow each other periodically. The wavelength ranges in measuring beam and comparison beam is selected by a graded interference filter which is arranged perpendicular to the optical axis and rotatable about this axis. In the zone of the graded interference filter the path of the beam is formed by two narrowly limited beams symmetrically to the optical axis. Both beams are produced preferably by two light sources whose distance may be varied in a direction perpendicular to the optical axis while the symmetry with respect to the optical axis is maintained.

Abstract: The contaminants in the exhaust gas emissions from a motor vehicle such as carbon monoxide (CO) and hydrocarbons (HC) are analyzed and the concentration of the contaminants together with other pertinent data is displayed in a digital manner. The exhaust gas emissions are fed into a sample cell contained within a nondispersive infrared analyzer and the absorption of an infrared radiation beam at selected wavelengths by the gas within the cell is measured. A reference cell containing a reference gas is also positioned in the infrared radiation beam path. By means of a rotating chopper disk positioned in the light path, the infrared radiation beam passes alternately through the reference cell and the sample cell and is focused at a plurality of detectors which are each sensitized to a narrow wave band by a filter and which receive the alternate sample cell and reference cell radiation pulses.

Abstract: A system for compensating for magnetic disturbances caused by the rotating stirrer magnet of a photometer sample cuvette on the photomultiplier tube of the photometer. To obtain the required compensation, a companion similar magnet is located coplanar with and adjacent to the main stirrer magnet and is counter-rotated synchronously with the main magnet in opposite magnetic phase therewith. The two counter-rotating magnets are physically located symmetrically with respect to the photomultiplier tube so that their magnetic effects on the electron flow of the photomultiplier tube cancel each other out. The companion magnet may be the stirrer magnet associated with a reference cuvette mounted in side-by-side relation to the sample cuvette. The counter-rotating magnets may be gearingly coupled together and may be mounted coaxially with respective ejection plungers associated with the cuvettes.

Abstract: The invention concerns an automatic continuous-flow fluid analyzer of the pe wherein a stream of fluid, segmented by air bubbles or other separating medium inert to the fluid to be analyzed, passes through a colorimeter flow cell. The bubble artifact is eliminated from the photoconductor signal while allowing the signal produced from the fluid segment to remain intact. This is accomplished by means of a signal comparator which operates as a digitally controlled differentiator, but could alternatively be a purely analog differentiator. The signal comparator through continual signal comparisons momentarily samples and stores a photoconductor output.For a finite period of time, the stored value is compared with all subsequent succeeding photoconductor output signals. If any signal that follows varies outside a preset range from the stored value, the comparator logic concludes that an air bubble is passing and the output to the recorder is not changed.

Abstract: A cylindrical block is provided with two ducts, forming a V whose legs terminate in exit windows in one axial end face of the block. A light source is disposed in the bottom of the V to direct light into both ducts. The block is further traversed by a bore, terminating as to one end in between the windows, avoiding the ducts and terminating in an offset position relative to the V-bottom and the light source at the other end of the block. A shaft traverses this bore for rotating a shutter in front of the windows. A complementary, light receiving unit is disposed with misaligned entrance windows in front of the unit windows, but their centers are traversed respectively by the optical axes of the ducts.