Abstract: A pulse color sorter which permits removal of internally and externally moldy pulse having afuratoxine as decomposition product is disclosed. The pulse color sorter comprises a first detector which provides a first and a second detection signal according to dispersed and transmitted light having two different wavelengths (for instance 700 and 1,100 nm) with different contents of information due to the separation of wavelengths, a second detector which provides a third detection signal according to reflected light, and a controller which calculates division of the first and second detection signals from the first detector, compares the resultant value calculated to a first predetermined threshold value while also compares the third signal from the second detector to a second threshold value, and outputs an eject signal if either of the compared signals is beyond the corresponding threshold value. According to the eject signal, corresponding defective pulse is forcibly ejected.

Abstract: A photometer readhead is used to measure concentrations within a test sample of preselected color-developed analytes having different characteristic absorption bands. The photometer readhead comprises an artificial light source for illuminating the test sample, a plurality of light-emitting diodes for detecting light transmitted through or reflected from the test sample, and a housing assembly for enclosing and supporting the plurality of light-emitting diodes. The plurality of light-emitting diodes have spectral responses encompassing respective ones of the different characteristic absorption bands of the preselected color-developed analytes.

Abstract: In an information gathering system especially suited to the monitoring of vegetable products in sorting apparatus, a light beam (23) is directed by a scanning source such as a laser (11) at the surface of an object (2) such as a tomato moving in the direction x--x through a scanning zone. The scanning operation is conducted in the y--y direction. Directly reflected light returned from the surface of the object (2) along a path (17) extending from light beam target region (12) is sensed by a line detector (14), which provides an output signal indicative of the level of the directly reflected light. Light entering the material of the organic product (2) is subjected to a light scattering or diffusing process within the material of the product, so that at least a region (13) of the surface of the product (12) surrounding the target zone (12) of light beam (23) becomes lit-up or illuminated from within.

Abstract: Probes according to the present invention practice a method of emitting light when the probe is positioned within a predetermined range of a workpiece surface, positioning the probe at a fixed position within the predetermined range of said workpiece, variably shaping the beam in response to variations of the relative distance between the probe and the workpiece within the predetermined range, and sensing a predetermined portion of the shaped beam when the workpiece surface is positioned at a point within the predetermined range, whereby the illumination intensity sensed varies substantially linearly throughout the predetermined range. In a non-contact form of the probe, the illumination is directed to vary the area of the light reflected from the workpiece surface in order to change illumination intensity at the sensor. In a contact form of the invention, a shade between a light source and a photosensitive receiver is displaced in response to plunger movement as the plunger engages the workpiece.

Abstract: In a stained particle analyzing method and apparatus for staining a test sample containing suspended particles, shooting an image of the stained sample, and classifying the particles and computing the density from the shot image of the sample, the sample, which may not be analyzed precisely, is detected before the start of an image analyzing process. Only the sample, which will be analyzed precisely, is stained and subjected to the image analysis. Color information of the sample before the staining is detected and stored. Color information of an image of the sample shot after the staining is compensated based on the color information of the sample detected before the staining. The sort and density of the particles are classified and computed on the basis of the image after the color compensation.

Abstract: An illumination system (12) for an optical inspection and sorting apparatus (10) includes a rare gas discharge lamp (36) for emitting select wavelengths of radiation. Rare gas discharge lamp (36) includes a light transmissive outer envelope (58) and contains one or more rare gases, and in particular neon, argon, or xenon. A hemi-elliptical reflector (48) having reflecting surface (38) directs the select wavelengths of radiation toward target specimens (16) in optical scanning area (24) in illumination area (20).

Abstract: A method and apparatus for determining the color of an object which is transparent, diffusing, and absorbent, by illuminating an area of the object by means of a diffuse light flux that is substantially uniform and isotropic, by picking up the light backscattered by a small fraction of the illuminated area of the object by means of an optical system that comprises achromatic doublets and both infrared and ultraviolet filters, together with a diaphragm, and spectrally analyzing said light by means of interference filters and photodetectors. The invention is particularly suitable for determining the color of teeth in the mouth.

Abstract: A flexible system for determining the quality of pharmaceutical products based on characteristics such as, for example, mass, shape, hardness, size, color and surface texture is disclosed herein. The quality determination apparatus includes a feeder assembly for sequentially dropping individual product samples upon an impact transducer arrangement. The impact transducer generates transducer signals indicative of the physical characteristics of each product sample. In addition, an imaging device operates to synthesize a digital image representation of each product sample. The transducer signal and digital image representation corresponding to each product are analyzed so as to determine the appropriate degree of quality to be associated therewith.

Abstract: A product discrimination system using a fiber optic sensing system and a line scan camera sensor for recalibration of the fiber optic system. A plurality of fiber optic sensing stations measure reflected light spectra of products conveyed past the stations. The line scan camera is positioned adjacent one of the fiber optic sensors at one of the stations. A standard object is positioned adjacent conveyor so as to also be viewed by the line scan camera. The line scan camera recalibrates itself based on the standard object and is compared with the adjacent fiber optic station to recalibrate results from the fiber optic system.

Abstract: A spectrophotometer apparatus (200) is adapted to provide spectral reflectance measurements of an object sample (236) under test, particularly optical characteristics of colored surfaces comprising metallic or pearlescent particles. The apparatus (200) comprises a source light (226) and a reflection optics assembly. Signals representative of reflected light are analyzed and data is generated representative of the spectral response characteristics of the object sample (236). The apparatus (200) employs a plurality of fiber optic bundles (248, 250, 252) for receiving light reflected from the object sample (236), with each of the fiber optic bundles (248, 250, 252) being positioned at one of a corresponding plurality of fixed angles different from the angle of illumination of the source light (226). Reflectance is measured at each angle by sequential switching such that light is impaired from being received by all but a subset of the plurality of multiple angles.

Abstract: The invention relates to a method and to apparatus for determining the color of a translucent object such as a tooth by measuring the reflectance of said object at wavelengths corresponding essentially to sensitivity maxima of the human eye to hue and to saturation, by calculating the luminance of white included in the luminance of the object illuminated by a determined standard illuminant, by calculating a saturation percentage for the color of the object as seen by the human eye, and by determining the pigmentations of said color relative to white.

Abstract: A hand-held combined spectrophotometer and gloss meter quickly and effectively measures the appearance of a color sample. Light generated by a krypton-filled tungsten bulb shines on the sample and is reflected at 45.degree. into twenty-one photodiodes spaced at staggered intervals around the sample stage. A diffuser in the light path reflects a portion of the light back onto a pair of red and blue sensitive reference photodiodes. The output of the red and blue reference diodes compensates for changes in the output of the bulb. An LED produces light which shines on the color sample at an angle of 30.degree.. The reflected light is received by a large-area photodetector which determines the gloss of the sample. A viewing port permits the user to view the sample prior to measurement. When the viewing port door is opened, it automatically actuates the light and illuminates the sample for viewing. The viewing port door is automatically closed by a return spring.

Abstract: A portable colorimeter housing has an upper portion which is mounted on a lower portion in a cantilever fashion and is adapted to receive sheets larger than the device for purposes of obtaining tri-stimulus color measurements. An adjustable paper guide determines the distance that a sheet is inserted between upper and lower plates. A sheet to be measured inserted in the opening will operate a micro switch which activates a motor operative to advance the sheet between a motor-driven drive wheel in the lower plate and an idler roller in the upper plate. Transmittance or reflectance measurements are taken by means of photodetector cells including colorimetric filters. A user programmable processor performs pattern recognition and control functions.

Abstract: A method and apparatus for printing a multi-colored image is provided. The image is composed of a plurality of single-color images, each of which is printed by an inking means in a base color ink. The reflectance of the image is measured by a spectrophotometer. Based upon the reflectance of the image and the full-tone reflectance of the base colors in the image, the effective dot density of each of the base colors are determined. The effective dot densities of the base colors of the image are compared to the effective dot densities of the base colors of an exemplary image. Based on the comparison, control signals are sent to the inking means to adjust the amount of ink used to print the single-color images. The effective dot density of the base colors of the image are determined from the reflectance of the image using a prediction process that incorporates a modified form of Neugebauer's model.

Abstract: The present apparatus makes use of a novel mineral identification system to not only identify the desired minerals and estimate a percent of mineralization, but also locate their presence on the mining face in an x, y coordinate manner in order to guide the mining operation of the associated robot mining apparatus. This is accomplished through the use of a camera and video monitor system which picks up the light returned from the mining face as illuminated by the light source. Therefore, on a pixel by pixel basis the camera identifies the light intensity returned from the mining face. In order to obtain the unique light signature of the desired minerals, a plurality of narrow band light filters is used to screen the light reflected from the mining face prior to its being focussed on the video camera.

Abstract: A confocal scanning optical microscope in which a specimen under test is simultaneously scanned with two distinct spots or slits of illumination and two output beams emitted from the specimen due to reflection or fluorescence are descanned and passed to separate stationary confocal apertures and detectors.

Abstract: A dynamic trip level setting apparatus is described for changing the comparison ratio with which products are optically sorted using first and second reflectance color values. The reflectance ratio for each image sorted is supplied to a RAM to update the RAM's memory. The dynamic values in the RAM are periodically employed to update a color sensitivity factor supplied to a battery-backed RAM. The battery-backed RAM value is employed in a logic device employing an algorithm and produces a variable output against which the ratio of "breaker" products (neither above a first color acceptance level nor below a second color reject level) is compared to produce a reject signal when the comparison results in an output indicating reject is appropriate.

Abstract: An object to be inspected is, for example, a medical capsule having differently colored surface areas. A beam splitter divides light reflected by the surface of the object into two parts. Each of the divided parts of the light is passed through an optical filter whose transmission wavelength range is set according to the colors of the object, to adjust the quantity of transmitted light from a high-brightness part of the object surface and the quantity of transmitted light from a low-brightness part of the object surface to a reference level. Image pick-up elements pick up images of the object surface according to the divided parts of the light and provide image signals. One of the image signals is selected and provided outside. Unlike a prior art that adjusts levels of signals by amplifying the signals according to brightness of an inspected object, the method and apparatus of the invention do not involve amplification.

Abstract: Systems and methods for material analysis are disclosed in which a material (e.g., a food of food ingredient) is illuminated at a plurality of discrete wavelengths. Measurements of the intensity of reflected light at such wavelengths are taken, and a analysis of reflection ratios for various wavelengths is performed. Changes in the reflection ratios are correlated with specific material properties such as the concentration of analytes or the condition of the material (e.g., spoilage, ripeness, degree of cooking or other processing stages).

Abstract: A method and an apparatus for measuring the color distribution of an item wherein the item is rotated in the field of view of a camera and successive line images of the item parallel to the axis of rotation of the item are measured and the data contents of the picture elements of the successive line images of the surface of the item are processed. In an embodiment in which the camera is a matrix camera, the item is at the same time transported through the field of view of the camera and the successive line images of the item are obtained from successive video lines of the camera.

Abstract: A device (1) for photoelectrically sensing the color of an object (18) includes a plurality of light emitting diodes (4, 6, 8) emitting light in a narrow range of wavelengths and where the light is transmitted through a corresponding fiber optic bundle (10, 12, 14) with a diameter in proportion to the transmission loss of the bundle and in inverse proportion to the emitted light energy of the corresponding light emitting diode and in proportion to the spectral response of a receiving photodiode (24). A receiving section (22) utilizes a PIN type photodiode (24) with an input section (40) that matches the shape of a receiving optical fiber bundle termination (42) where the photodiode (24) converts the reflected light from the object (18) into electrical signals which are then processed by a microprocessor (28) which also controls the activation of the light emitting diodes (4, 6, 8) and outputs a signal indicative of the color of the object (18).

Abstract: A two-color focal plane array sensor arrangement (10) operative to simultaneously sense optical energy within first and second wavelength spectra from a scene within a field of view is disclosed herein. The sensor arrangement (10) includes a telescope (12) for collimating the optical energy within the field of view into first and second substantially overlapping beams. The first beam includes optical energy within the first wavelength spectrum, and the second beam includes optical energy within the second wavelength spectrum. A wedged beamsplitter (14) having a pair of non-parallel reflective surfaces (34, 36) redirects optical energy within the first and second beams to a focusing lens (18). The focusing lens projects the redirected optical energy from the first and second beams on first and second regions of a focal plane, respectively. First and second detector arrays (20, 22) positioned in the focal plane generate electrical signals in response to illumination by the projected optical energy.

Abstract: A fiber optic apparatus and method for monitoring color balance of a product that can consist of a complex two dimensional color pattern. This system employs at least one illuminating optical fiber (18) and at least two pick-up optical fibers (16). Filters (36) associated with each of the pick-up fibers (16) separate the reflected light into different color components. Photodetectors (38) convert the light intensity from each fiber (16) into analog electrical signals which are routed to a microprocessor based signal processing module (10) for conversion to digital output and subsequent analysis for monitoring color balance. If there is a change in color balance, a visual and/or acoustic alarm (62) is automatically activated.

Abstract: A product discrimination system using a lens assembly for projecting an image of the product unit toward a randomized fiber optic cable. The end of the fiber optic cable is constructed in a rectangular section such that a long thin section of the product unit is viewed at any given time. The cable discharges the light at a lens and filter arrangement such that the emitted light may be divided into portions and filtered for measurement by photodiodes of specific and different wavelengths. Through a comparison of the wavelengths to a standard, attributes of the product unit can be determined. A method for distinguishing between adjacent product units which are not separated one from the other employs sensing a plurality of decreasing widths followed by a plurality of increasing widths to establish a product end therebetween. Off-loading elements on the conveyor are assigned by location of the product units.

Abstract: A method for detecting the presence or absence of microorganisms in a liquid test sample is provided without need for withdrawing an aliquot or destroying the sample. The method comprises taking near-infrared spectra of the sample and comparing it visually or mathematically to the spectra of a standard, which may be the values of the spectra known to the operator or may be a standard sample that is provided and run side-by-side.

Abstract: To improve the control of the inking process in an offset printing machine, color measuring fields provided on printed sheets are evaluated not as heretofore densitometrically but colorimetrically by means of spectral measurements. Spectral reflections are used to match colors, or color coordinates are calculated from them and compared with corresponding set reflections or set color coordinates. The color deviations obtained in this manner are used to control the inking process. For the stabilization of printing runs the spectral reflections are converted into filter color densities and the inking process is controlled on the basis of these color densities in a conventional manner. The control of the inking process using color deviations and control using color denisty may be superposed upon each other. The process makes it possible to adapt color impressions in delicate locations of importance for the image in the print to the corresponding locations of the proof.

Abstract: A method and apparatus is disclosed for grading the surface of generally apherical fruit according to surface characteristics such as color and blemish. The fruit are moved in single file past a scanning camera while being rotated about a transverse horizontal axis. Reflectivity data in three separate wavelength bands is collected for a series of scans of each article of fruit, and this data is processed to eliminate all duplicative data arising from the fruit's rotation. Color ratio signals based on the remaining reflectivity data are then utilized to grade the fruit according to their surface color and degree of blemish.

Abstract: A lighting control system for maintaining the light source and measuring components of a color measurement station in a stabilized condition. A high frequency fluorescent lamp drive is controlled by a ballast which is adjusted by a control signal generated by using a video camera to simultaneously view a standard tile and a test sample. One of the color signals in the standard tile portion of the signal is compared with prescribed information stored in a computer, and if the standard tile signal differs from the prescribed information, the microcomputer adjusts the fluorescent lamp drive until the signal from the standard tile reaches the prescribed level, at which time the color signals from the test sample are evaluated while the lamp intensity and camera response are generating standardized measurement conditions.

Abstract: Color measurement system for offset printing, having a bridge for spanning an original which is to be measured and a color-measuring device movably disposed on the bridge, the color-measuring device comprising a first three-color simultaneous measuring head for densitometric measurement, and a second three-color simultaneous measuring head for colorimetric measurement.

Abstract: Apparatus for low cost measurement of light energy in terms of multiple spectral integrations with differing wavelength-dependent weights for consistency of measurements in spite of variations in component characteristics or temperature.

Abstract: A color image processing apparatus generates color image data, measures the quantity of the image data within a predetermined region of color space, obtains a representative color value for the image data within that region, and corrects the color image data based on the representative value and the measured quantity.The number of image data which exist within a predetermined region on a (u,v), chromaticity diagram and which are among input color image data is counted. When the counted number is smaller than a predetermined value, the correcting operation is not executed. The difference between a predetermined coordinate point and a coordinate point at which the largest counted number of image data exist is obtained, and by the obtained distance either all the image data or the image data within the predetermined region are corrected.

Abstract: An apparatus for color control of objects (11) has an approximately point-shaped light source in the form of a xenon flash lamp (16), which illuminates a specific, desired area through a diaphragm (17). Light reflected from the object is received by a detector unit (13) having three or more sensors (22) with their respective spectral sensitivities, which are positioned at such a great distance from the object that each receives substantially the same amount of light from all parts of the illuminated area. The detector signals are amplified by amplifiers adapted to filter all signals exhibiting another timewise variation than the light source, so that disturbing influence from the surroundings is avoided. The apparatus is simple and fast and is versatile in use.

Abstract: Optical analytical instruments to determine a physical parameter of a fluid, and methods of operation of such instruments, are shown. These employ a source of suitable optical radiation, a detector means, means defining a zone for the fluid, means defining an optical path from the radiation source through the fluid zone to the detector means, and reading and control circuitry. At least two readings of optical energy that has been influenced by the fluid are taken without there having occurred substantial change to the fluid. During one of the readings a filter of known absorbance is included in the optical path so that the respective reading represents a calibration reading.

Abstract: An optical pyrometer for use with jet engines is characterized by the use of three spectral areas or bands in a temperature computation. A target temperature is optically distinguished from background radiation by dividing a received optical beam into three spectral components which are comprised of emitted and reflected radiation. A controller computes the measured power in each band as a function of the emitted power by the target and a ratio of reflected power in adjacent bands to yield signals of reflection corrected radiation. These are used with the reflected power ratios to determine values of temperature in adjacent bands. The difference between these computed temperatures is iteratively adjusted until the difference therebetween is approximately equal to a preselected value.

Abstract: A densitometer apparatus (410) is disclosed and is adapted to provide color density measurements of object samples. The densitometer apparatus (410) comprises a source light (580) for projecting light toward an object sample comprising a control strip (588, 620). A reflection optics assembly (576) is adapted to measure light density reflected from the object sample when the object sample is in the form of a paper control strip. A transmission optics assembly (618) is adapted to measure transmission density of light rays projected through the object sample when the object sample is in the form of a film control strip. A motor assembly (426) operating with a drive wheel assembly (434) and idler wheel assembly (440) automatically moves the object sample (588, 620) through the apparatus (410) adjacent the source light (580). A pair of guides (468, 470) are selectively adjustable by the operator to control movement of the object sample (588, 620) through the apparatus (410).

Abstract: A product discrimination system using a lens assembly for projecting an image of the product unit toward a randomized fiber optic cable. The end of the fiber optic cable is constructed in a rectangular section such that a long thin section of the product unit is viewed at any given time. The cable discharges the light at a lens and filter arrangement such that the emitted light may be divided into portions and filtered for measurement by photodiodes of specific and different wavelengths. Through a comparison of the wavelengths to a standard, attributes of the product unit can be determined. A method for distinguishing between adjacent product units which are not separated one from the other employs sensing a plurality of decreasing widths followed by a plurality of increasing widths to establish a product end therebetween. Off-loading elements on the conveyor are assigned by location of the product units.

Abstract: A non-invasive method and apparatus are described for measuring the oxygen concentration in the infected cells of the nodules of nitrogen fixing plants in the laboratory or field. In many cases, this information can be used to estimate the nitrogenase activity, and therefore the nitrogen fixation rate, in these nodules since recent studies have shown that the oxygen concentration limits and controls nitrogenase activity under most environmental conditions. Using the same apparatus, a method to measure nodule respiration and nodule oxygen permeability is also described. The nodule oxygen concentration in the infected cells of nodules is maintained at very low levels and has not been measurable previously by non-invasive techniques.

Abstract: A method for the quantitative determination of antigen (or antibody) which comprises adding a sample containing an antigen (or antibody) to a dispersion of an insoluble carrier of fine particle size with an antibody (or antigen) fixed thereto to effect an antigen-antibody reaction, measuring absorbance of the reaction mixture, A.lambda..sub.1 and A.lambda..sub.2, at two different wavelengths, .lambda..sub.1 and .lambda..sub.2, and calculating the concentration of said antigen (or antibody) in the sample from the absorbance ratio A.lambda..sub.1 /A.lambda..sub.2. This method is suitable for the measurment of the amount of an antigen or antibody in samples taken from living bodies using a simple procedure which has high sensitivity.

Abstract: A meat freshness measuring apparatus measures the freshness of meat by detecting changes in a pigment contained in the meat. For this purpose, the meat (2) is exposed to rays of light of different wavelengths applied from a light source (1), and the rays obtained from the meat are separated into spectra for the respective wavelengths, which are received by a photoelectric conversion element (4). Spectrum data for each wavelength are amplified and then the amplified data are converted to a digital signal by an A/D converter (7), whereby the digital signal is stored in a RAM (12). Based on the stored spectrum data and using a prescribed equation of calculation, a content of the pigment in the meat is calculated and outputted by a CPU (10).

Abstract: A scanning densitometer is disclosed for obtaining color density measurements from colored samples, such as color bars and the like. The scanning densitometer includes a densitometer head (100) and a densitometer head transport system (101) having transport bars (102, 103). A sample sheet is positioned under the transport bars (102, 103) and the self-propelled head (100) moves over the sheet along the bars (102, 103) toward an end limit stop (105). During a return movement from the end limit stop (105) to a docking end housing (110), color measurement data is obtained. Upon docking at the docking end housing (110), an optical communications interface is provided so that data from the densitometer head (100) can be transmitted to a host computer.

Abstract: A densitometer apparatus (210) is disclosed and is adapted to provide color density measurements of object samples. The densitometer apparatus (210) comprises a source light (578) for projecting light toward an object sample comprising a control strip (588, 620). A reflection optics assembly (576) is adapted to measure light density reflected from the object sample, when the object sample is in the form of a paper control strip. A transmission optics assembly (618) is adapted to measure transmission density of light rays projected through the object sample, when the object sample is in the form of a film control strip. A motor assembly (426) automatically moves the object sample (588,620) through the apparatus (210) adjacent the source light (578). Pattern definition data is prestored in memory of the apparatus (210).

Abstract: A color measuring apparatus for measuring the color of a sample has a light source measuring section for detecting color temperature of light coming from a light source without passing through or being reflected by the sample. Relationship between a plurality of color temperatures and a plurality of emission time periods of the light source is stored in a memory. A microcomputer compares each of detected color temperatures with a predetermined value and determines a certain time period on the basis of both the relationship stored in the memory and a comparison result. A lighting circuit energizes the light source during the time period determined by the computer so that the light source keeps lighting the sample. A sample measuring section detects light coming from the sample and the microcomputer measures a color of the sample.

Abstract: A Method and Apparatus for identifying and distinguishing fluids and for recognizing contamination of a fluid, which method and apparatus utilizes spectrographic analysis of control samples of known fluids and then spectrographic analysis of unknown fluids to generate optical signatures, finger prints and/or profiles of data and processed data relating to the relative intensities of light at selected wavelengths; and then, through comparison of the various signatures, fingerprints and/or profiles, provides determinative information as to contamination or non-contamination of the unknown fluids; after which appropriate operation control is effected and/or exercised.

Abstract: A method and apparatus for identifying and distinguishing fluids and for recognizing contamination of a fluid, which method and apparatus utilizes spectrographic analysis of control samples of known fluids and then spectrographic analysis of unknown fluids to generate optical signatures, finger prints and/or profiles of data and processed data relating to the relative intensities of light at selected wavelengths; and then, through comparison of the various signatures, fingerprints and/or profiles, provides determinative information as to contamination or non-contamination of the unknown fluids; after which appropriate operation control is effected and/or exercised.

Abstract: An optical density detector which comprises a first light source for emitting a first light which belongs to a wavelength region in which the first light is hardly absorbed by a specific material contained in a sample, a second light source for emitting a second light which belongs to a wavelength region in which the second light is absorbed, substantially as compared with the first light, by the specific material, wherein a peak-wavelength of the second light is shifted by change of a temperature and change of an absorption of the specific material caused by the peak-wavelength shift is characteristic of a linear equation with a gentle grade, light receiving device for measuring a quantity of the first and the second lights which are transmitted through the sample, an arithmetic unit for calculating difference of absorbance between the first light and the second light of which both change depending on the density of the specific material, a temperature measuring device for measuring the temperature of the fi

Abstract: A bioassaying device for carrying out an experiment with a subject placed under a transparent portion of a base plate. The subject is irradiated with light rays emitted from light-emitting ends of three fiber optic cables. One of the three fiber optic cables radiates light rays containing plenty of the red color-spectrum component, another cable radiates the blue component and the remaining cable radiates the green component. Each of the fiber optic cables is provided with a mechanism for adjusting its inclination angle simultaneously with vertical movement of a moving plate upon which the fiber optic cables are mounted.

Abstract: In a colorimetric sensor having a plurality of color sensors each of which is composed of a photo-electric conversion element for converting light into an electrical signal and a color filter added to the photo-electric conversion element for transmitting light of a specific wave length region, each of the color sensors is composed of a plurality of polygonally split pieces radially extending and spreading from a central part of the colorimetric sensor. A color sensor of a relatively low sensitivity has a greater number of split pieces than others. Among these color sensors, a color sensor having the lowest sensitivity has its split pieces either partially or totally disposed in a position covering two sides of an angular corner part of the colorimetric sensor.

Abstract: The method of the present invention employs an enzyme immunoassay for measuring the concentration of an analyte in a sample by indirect colorimetric detection. An incident light beam at a plurality of wavelengths is directed into a liquid solution containing an analyte of interest. The solution is capable of attenuating the amount of light at a first wavelength received from this solution as a function of the increasing concentration of the analyte present. A light signal from the solution at the first wavelength is detected, and light at a second wavelength, at which substantially no attenuation of light signal occurs as the concentration of the analyte increases, is also detected. The ratio of the two respective wavelengths is formed and that ratio is compared with ratios of known amounts of the analyte to determine the amount of the analyte in the sample.

Abstract: In a method wherein sets of measured values of the intensity of electromagnetic radiation, which has been subject to optical interference, absorption or scatter by a sample, are correlated with different sets of known values derived from either a model of the optical properties of the sample, or from an analogue technique, correlation is by means of either a zero dependent correlation function, or a normalized residual function. Both functions are unaffected by gain factors, thereby avoiding any need to determine and to maintain absolute sensitivities of optical detectors; provide greater variation of correlation than with techniques employing a conventional correlation coefficient, thereby increasing the precision with which the optimum correlation can be determined, especially when either the measured value, or known values are subject to error; enable the method to be carried out with only two radiation components; and can enable a reduction in computing time.

Abstract: A projection exposure apparatus is disclosed for exposing a semiconductor wafer to a pattern, formed on a reticle, by projection using a projection lens system. The apparatus includes an alignment optical system disposed at a side of the wafer remote from the projection lens system. The alignment optical system is used to detect an alignment mark provided on the wafer, from the back of the wafer. In accordance with the detection, the wafer is moved so that its alignment mark is brought into a predetermined positional relation with the alignment optical system, whereby the reticle and the wafer are relatively aligned. With this arrangement, the wafer alignment mark can be detected without being adversely affected by a resist layer applied to the wafer surface. Thus, the reticle and the wafer can be aligned very accurately.