Abstract: An apparatus and method are used for determining the cleanliness of an electronic circuit assembly (ECA) such as printed circuit boards (PCB) following noraml cleaning and flux removal processes. The apparatus and method are used to quantitatively measure the ionic and organic contaminants remaining on an ECA. The apparatus utilizes small volumes of isopropanol, a conductivity/resistivity probe and cell and a spectrophotometric analytical instrument. The apparatus generally provides for washing the "cleaned" of defluxed ECA with a measured volume of isopropanol and thereafter measuring the ionic and organic contaminants in the wash solution. The results can then be compared to a standard.

Abstract: In an atomic absorption spectrometer with an atomizing device (190) and a line emitting light source (16), an optical system (22,28 . . . ) for generating a measuring light beam (18), and a photo-electrical detector (38), which are arranged in a housing (10) which forms a sample cavity (12) accessible from the outside and which is passed through by a measuring light beam (18) and into which different atomizing devices can be optionally inserted, the atomizing device (190) with the specific components (104,124,126) is assembled to form an insert unit (100) in which the atomizing device (190) in the form of a graphite furnace has a well-defined position relatively to the insert unit (100) and which in turn can be inserted into the sample cavity (12) in a well-defined position to provide an entirely functioning atomic absorption spectrometer.

Abstract: A method identifies components in a sample by spectrally analyzing the sample in a spectrophotometer. The sample data points output from the spectrophotometer are detected in a detector before being stored in an array in a data station. A preselected smoothing bandwidth is entered into the data station from a keyboard. The bandwidth is converted to a strength parameter; and thereafter each of the smoothed data points is stored before being output as an array of smoothed data points to form a modified spectral display, which identifies the components in the sample.

Abstract: The present invention comprises a product moving apparatus for moving a tobacco product, a vertical feeder tube for metering the tobacco product onto the product moving apparatus at a predetermined rate, a system for maintaining a predetermined height of the tobacco product in the feeder tube, and an infrared detection apparatus connected to the feeder tube to detect the concentration of menthol in the tobacco product.

Abstract: A calibration method and apparatus for economical and rapid calibration of a scientific instrument utilizing a monochromator to generate monochromatic light utilizing controllable means for determining the angular position of a light dispersing element in the monochromator and a filter having a narrow absorption band(s) to determine a relationship between the wavelength of the monochromatic light generated by the monochromator and an angular position of the dispersing element so that the dispersing element can be rotated to an exact position for the monochromator to generate a selected wavelength of monochromatic light.

Abstract: A test system in a standalone chassis without a power cord. The testing subsystem (e.g. a spectrophotometer) is microprocessor-controlled, and the microprocessor is disconnected from the battery during normal operation. An ancillary integrated circuit controls the power supply to the microprocessor, and periodically powers up a proximity sensor subsystem (e.g. a photodiode/LED pair), without powering up the microprocessor. The ancillary circuit powers up the microprocessor IF the proximity sensor subsystem, after being activated, indicates that a sample has been inserted by a user. The microprocessor can then operate the testing subsystem, and provide output data to a display driver accordingly.

Abstract: An automatic chemical analyzer for the analysis of physiological samples. A scanning monochromatic spectrophotometer may be used to determine the absorbance of the sample under control of a central processing unit. Outputs from one of several ion selective electrodes may also be selected by the system. The information obtained from the measurements is stored in memory or ouputted to output devices. Information about the test parameters may be read from an optical bar code associated with the test kit for the particular chemical analysis.

Abstract: In a color measuring instrument, an integrating sphere is used to illuminate the sample and fiber optics are used to carry light diffusely reflected from the sample and from an interior wall of the sphere to a spectrometer. The transmitting ends of the fiber optic bundles are fixed in the housing of the spectrometer as entrance slits for the spectrometer, which includes a fixed grating and one or two arrays of photodetectors to detect the spectra dispersed by the grating from light received from the two transmitting ends.

Abstract: A method and apparatus for the qualitative and quantitative spectroscopic investigation of elements present in a liquid sample using the laser spark. A series of temporally closely spaced spark pairs is induced in the liquid sample utilizing pulsed electromagnetic radiation from a pair of lasers. The light pulses are not significantly absorbed by the sample so that the sparks occur inside of the liquid. The emitted light from the breakdown events is spectrally and temporally resolved, and the time period between the two laser pulses in each spark pair is adjusted to maximize the signal-to-noise ratio of the emitted signals. In comparison with the single pulse technique, a substantial reduction in the limits of detectability for many elements has been demonstrated. Narrowing of spectral features results in improved discrimination against interfering species.

Abstract: A color sensor comprising a plurality of detecting units. One of the detecting units may inspect the color of an object to be examined, and the other may inspect the color of the reference object simultaneously and independently. The reflected light of the object to be examined is corrected by the reflected light of the reference object. The lights reflected from the object to be examined and the reference object are derived from the same light source.

Abstract: An atomic absorption spectrophotometer for simultaneously measuring a plurality of elements different in kind from each other. A cylindrical heating furnace is provided for heating a sample being analyzed to dry, ash and atomize the sample thereby producing atomic vapor. A plurality of hollow-cathode discharge tubes corresponding in number to the elements being detected are arranged for simultaneously emitting light beams respectively containing line spectra of the respective elements, to cause the light beams to be incident upon the heating furnace at respective angles of inclination with respect to a central axis of the heating furnace. A plurality of spectral detection systems are arranged behind the heating furnace in relation to the angles of inclination, for respectively spectral-diffracting and receiving the light beams having their respective line spectra absorbed by the atomic vapor.

Abstract: The present invention relates to an improved dual beam multichannel spectrophotomer employing a simple and novel optical system in combination with photodiode arrays and a unique logrithmic data converter to convert light signals to absorbance. In particular, the optical system utilizes optical elements in a novel arrangement to direct a pair of equivalent sample and reference beams in an essentially parallel formation respectively through a sample and reference cell and to focus and direct the emergent sample and reference beams to a single flat horizontally ruled grating which disperses each of the sample and reference beams respectively onto a pair of vertically disposed photodiode arrays whereby the light signals are converted into absorbance units (AU) by an unique logarithmic data converter. The spectrophotometer is highly accurate, has very low drift, less than 2.times.10.sup.-4 AU/.degree.C., and very low noise, less than .+-.2.times.10.sup.-5 AU.

Abstract: A calibration method and apparatus for economical and rapid calibration of a scientific instrument utilizing a monochromator to generate monochromatic light utilizing controllable means for determining the angular position of a light dispersing element in the monochromator and a filter having a narrow absorption band(s) to determine a relationship between the wavelength of the monochromatic light generated by the monochromator and an angular position of the dispersing element so that the dispersing element can be rotated to an exact position for the monochromator to generate a selected wavelength of monochromatic light.

Abstract: The invention can be used to determine the color to be given to a dental prosthesis, for example, on the basis of color measurements performed on adjacent teeth in the mouth of the patient. An optical fiber instrument picks up light reflected from a tooth and transmits it to the inlet of a spectrocolorimeter which associated with a microprocessor in order to determine the diffuse spectral reflectance of the tooth and to calculate the tristimulus values of its apparent color under various different types of illumination. The invention is particularly suitable for determining the color of dental prostheses.

Abstract: A method and apparatus for analysing the spectrum of light reflected by a reflecting structure (24) in which the effect upon the analysis results of variation in the angle between the reflecting structure and the incident beam (22) is minimised. The method and apparatus may utilise a dispersive element (26) constructed and arranged so as to minimise the effect of the variations. The method and apparatus may also utilise a calibration technique in which light with a known spectrum is reflected off the reflecting structure and analysed so that compensation may be made for the effect of the variation.

Abstract: An analyzing apparatus provided with a spectroscopic photometer, in which light emitted by a deuterium lamp enters a flow cell; light transmitted by the flow cell is divided into two light beams by means of a beam splitter, one of which is received by a detecting element for sample measurement and the other of which is received by a detecting element for monitoring through a filter transmitting only light in a predetermined wavelength region, which is not essentially absorbed by the sample; and a signal processing device compares the output signal of the detecting element for sample measurement with that of the detecting element for monitoring and effects necessary operations.

Abstract: Equipment for the emission and distribution of light by optical fibres, particularly for in-line spectrophotometric control with the aid of a double beam spectrophotometer, namely one channel for the reference and one channel for the measurement. It has at least one complementary light source emitting through a system of optical fibres permanently towards a reference cell and sequentially towards one of the n measuring cells corresponding to the controls to be performed, the light information from the reference cell on the one hand and sequentially from each of the n measuring cells on the other being passed by the system of optical fibres respectively to the reference channel and to the measuring channel of the spectrophotometer.

Abstract: A process which extends the measurement range of Zeeman atomic absorption spectroscopy by linearization of the calibration curve in the region of relatively high sample concentration. The intensities of the Zeeman components I.pi.o, I.sigma.o, I.pi. and I.sigma.

Abstract: An analysis system includes a sample inlet, a diluent inlet, and a mixing chamber that has an outlet through which a mixture of the sample and diluent is flowed and in which a mechanical mixing member is housed. Positive displacement pumps preferably concurrently flow diluent to the mixing chamber and draw diluted sample to be analyzed from the mixing chamber. Bubble separation apparatus has a first branch connected to a drain and a second branch connected to the analyzer input. In a particular embodiment, the analyzer apparatus includes a nebulizer that controls the flow rate of the bubble-free stream through the second branch, sample excitation apparatus in the form of an induction coupled plasma (ICP) torch for exciting the sample to spectroemissive levels, and means for spectroanalysis of the excited sample at the output of the torch.

Abstract: A measuring apparatus includes a freely moving measuring head which is connected to a stationary base unit via light conductors and an electrical cable. The radiation reflected from the sample is simultaneously measured at three different angles. For this purpose, three diode-array spectrometers are provided in the stationary base unit. The spectrum of the radiation illuminating the sample can be simultaneously measured with a fourth diode-array spectrometer.

Abstract: A spectrophotometer (10) is provided having the capability to accurately measure spectral reflectance at relatively long sample distances. A first illumination optics arrangement (14) assures uniform illumination to a portion of the sample and a second optical arrangement (20) focuses the reflected image of part of the illuminated sample onto a polychromator (22). Reference beam means are provided so that the polychromator sequentially measures the spectral characteristics of the reference beam and the sample. Continuous monitoring of the illumination at select wavelengths provides illumination normalization data so that a microprocessor (40) can normalize the illumination and compare the reference beam and sample measurements to accurately determine the spectral reflectance characteristics of the sample. Angular and raster scanning capability is also provided.

Abstract: An apparatus for measuring transmission characteristics of a short optical fiber comprises a streak tube having a photoelectron-emitting surface for receiving through a connector light pulses transmitted simultaneously through a reference optical fiber and an optical fiber under test. The light pulses are generated by a laser and cause the streak tube to generate an optical output signal indicating time-wise changes in the luminance of the pulses transmitted through each of the optical fibers such that differences in light transmission characteristics between the reference optical fiber and the optical fiber under test may be determined.

Abstract: An optical scanning device, such as a chromatoscanner, includes a spectroscope having a rectangular outlet slit for producing a light beam in the shape thereof. A rotatable disk having a spiral slit is disposed in the path of the light beam to produce light pulses along radial lines of the disk which are directed to the surface of a specimen. The absorbancy of the light pulses at discrete positions of the specimen is measured and stored in a memory in accordance with the corresponding location on the specimen as derived from measuring the rotation angle of the disk.

Abstract: The invention relates to a spectrometer/colorimeter apparatus comprising an opto-electronic card (12) with the essential components of the apparatus mounted thereon, and in particular a spectrometer (14) having an inlet slot (16) and a strip (18) of photodetectors (20), and two optical fiber measurement paths (28) and two calibration paths (26), with the ends of the optical fibers being superposed in the inlet slot (16) of the spectrometer. The apparatus is particularly intended for use in an industrial environment.

Abstract: A reflectance measuring apparatus for contactless measurement is described, in which the result of measurement is not dependent on the distance from the test object within a predetermined range. This is attained by disposing the light source in the focus of a condenser, and by providing that the measuring area is smaller than the core region inside the irradiated area on the surface of the test object.

Abstract: Optical apparatus and methods are employed in the determination of impurity components present in both homogenous and non-homogenous light-scattering products. Light sources having wavelengths in the visible and near-infrared regions are preferred.

Abstract: There is disclosed herein a reference system for a fluorometer designed to detect very low levels of materials tagged with fluorophores. There is also disclosed an optical system for use in such a system which improves the signal to noise ratio. The reference system utilizes pulsed arc light excitation which excitation pulses are directed onto a flow cell containing the fluorescent dye. Fluorescent light emitted from the dye is guided to a photomultiplier tube which converts it to electrical pulses. A portion of each excitation light pulse is guided by a light pipe onto a PIN diode light detector which converts these light signals to electrical pulses. A LED reference light source is pulsed to generate a plurality of reference light pulses one of which occurs between each excitation pulse. A portion of each of these pulses is guided to each of the two light detectors and two more series of electrical pulses are generated.

Abstract: A record of calibration data containing determined values required for accurate operation of a scientific instrument measuring transmissions or absorbance of light in analysis is provided. A method of maintaining and using the records generated by the instrument permits use of the instrument to determine which records are required for efficient and easy instrument usage.

Abstract: A method of calibrating reflectance measuring devices, such as spectrophotometers, that incorporate automatic gain or sensitivity setting capability. According to the method, offset reflectance and reflectance of a secondary reflectance standard for several wavelengths are calculated and stored in a memory of a reflectance measuring device. A secondary standard is mounted in the reflectance measuring device and reflectances at a selected wavelengths from the secondary standard are read prior to measurement of the reflectance of the test sample. The stored offset reflectance and secondary reflectance for the operational wavelength are used to calculate true reflectance of the test sample.

Abstract: To reduce noise in an absorbance monitor in which the light source is a deuterium lamp, an aspheric condensing mirror focuses light from an approximately 0.6 mm-high by 2 mm-wide part of the central bright spot in the deuterium lamp through a slit in an aperture plate which blocks all other light and an aspheric monochromator mirror focuses the light onto a plane reflective diffraction grating, which: (1) is mounted for orbiting about an axis parallel to the longitudinal axis of the slit; and (2) adjusted so that, as it orbits it reflects a selected wavelength of light to a beam splitter. Each beam is focused upon and transmitted through a different one of two equal oval apertures optically at least as large as the height of the image of the aperture near the lamp.

Abstract: A two-beam spectrophotometer comprising a monochromator and a beam splitter is provided. In addition to being inclined to the optical axis by an angle .alpha./2 lying in the optical plane, the beam splitter is inclined to the direction perpendicular to the optical plane, so that the reference beam is deflected out of the optical plane by an angle .beta.. This improves the spectral intensity distribution.A spectrophotometric method employing this apparatus is also provided.

Abstract: A photometric apparatus includes a light source, apparatus for oscillating a light beam spot across a sample, apparatus for measuring secondary light from the sample, and apparatus for determining the specific portion of the sample to be examined by photometry. With this photometric apparatus, each of a plurality of microscopic areas of the sample can be evaluated accurately.

Abstract: Apparatus for spectroanalysis which comprises a spectrophotometer, a first memory for storing programs for different types of unit data processing operations, a second memory having a plurality of channels for storing data, a keyboard containing a first group of keys for designating said programs, a second group of keys for entering parameters for data processing, and a key for selecting a multiple data processing mode, and a control circuit.

Abstract: Laser detection apparatus comprising a laser defining an active region and providing a double beam of coherent radiation, a sample to be tested located in a first part of the double beam of coherent radiation, a radiation detector arranged to receive radiation passing through the sample to be tested for providing an output indication of absorbance, a reference sample disposed in a second part of the double beam, apparatus for sensing absorption of the coherent radiation at the reference sample, apparatus for providing selectable heating of the active region of the laser, and apparatus for providing a control signal to the selectable heating apparatus in accordance with the sensed absorption of the coherent radiation at the reference sample.

Abstract: A flash tube (1) illuminates the inlet slit diaphragm of a monchromator illuminator (3) the outlet slit diaphragm of which is applied to an optical conductor (5) forming a statistically balanced derivation towards a measuring cell (6M) and a reference cell (6R). Quantic photodetectors (7M and 7R) measure respectively the light conveyed by the two cells. The electric signals obtained are amplified and digitalized, and a microcomputer (9) calculates the relation between the measuring signal (M) and the reference signal (R), other things being equal.

Abstract: This invention is directed to a digital wavelength calibration system for a spectrophotometer, which includes a photodiode array that forms an output detector for the spectrophotometer, a light source for generating at least one reference emission line of known peak wavelength, a computer controlled mechanism for causing the peak of said reference line to fall in close proximity to the center of a preselected pixel of said photodiode array, peak location computing apparatus for computing the exact position data of the peak relative to the pixel center in terms of the pixel spacing and the ordinal number of the preselected pixel and for retaining this position data for subsequent wavelength computation, wavelength identification computing apparatus for computing the numerical relationship data of the ordinate number of each pixel to the wavelength falling on that pixel and for retaining this relationship data for subsequent correlation with data generated by the pixel, and apparatus for computational processin

Abstract: An automated chemistry-testing system for analyzing serum samples in which a controlled intensity, monochromatic light beam of substantially any desired wavelength can be selectively directed through any one of a plurality of test solutions in a spectrophotometer. The system operates at very high speed, permitting serum test solutions to be scanned with a multiplicity of wavelengths of light to provide extensive data on the characteristics of the serum. The invention also provides substantial flexibility and permits a wide variety of test to be more reliably performed.

Abstract: A sequential spectrophotometer system having a light source, a scanning type monochromator, a stepper motor means for changing the monochromator wavelength over a light spectrum being scanned, a photomultiplier for measuring the intensity of light absorption or passage through a sample being tested and generating a signal corresponding thereto, data acquisition means for compiling data corresponding to said signals and means for recording such data generally as a function of light measured for each wavelength, the improvement comprising:a method and means to effect the data acquisition conversion at or about each desired wavelength during a respective stepper motor rotor displacement period, i.e., during each corresponding period of diffraction grating vibration or oscillation following a stepper motor disposition thereof to another wavelength position angle.

Abstract: An apparatus and method for determining the relative proportions of two eents of a ternary compound from light reflected off a sample of the compound. The light is varied in wavelength and a graph of reflectance vs wavelength is stored. For a given compound of general form A.sub.x B.sub.1-x C, x may be determined by converting the stored graph to a graph of reflectance vs photon energy of the light, determining the photon energy of the light for the longest wavelength peak on the converted graph, and computing x from the equation E.sub.1 =a+bx+cx.sup.2 wherein a, b, and c are predetermined constants, and E.sub.1 is the photon energy in electron volts of the peak of interest.

Abstract: In a spectrophotometer having an optical beam chopped into dark and light segments, a computer controlled system is described for determining background signal due to stray light, photomultiplier dark current, offsets of photometric amplifiers and other components, and the like and for subtracting this background signal from the overall signal so as to leave only the desired light measurement. The same computer system also sets the signal level automatically for highest resolution. Furthermore, the same computer acts as an analog to digital converter by successive approximation to supply the photometric signal to the microprocessor unit. Since the same components are involved in all these functions both analog and digital offsets of the components are automatically cancelled.

Abstract: Spectrophotometer purge apparatus comprising a sample compartment including a plurality of walls defining a first sample purge volume. The apparatus may further include a volume reducing wall and fastening means for removably fixing the volume reducing wall within the sample compartment to thereby define a second sample purge volume smaller than the first sample purge volume. A purge gas inlet introduces purge gas into the sample purge volumes. Further the apparatus may comprise a movable partition forming one of the plurality of walls and the volume reducing wall. In such an embodiment, the fastening means may further include means for removably fixing the movable partition to thereby define the first sample purge volume. The apparatus advantageously enables the sample purge volume to be adjusted as required to thereby optimize purge efficiency in a spectrophotometer.

Abstract: A spectrophotometer is provided for measuring and displaying an absorbance change as a function of time, a wavelength spectra, or an absorbance difference as a function of time between two specific wavelengths, which comprises a wavelength scanner for scanning through a plurality of wavelengths in a scan range, a wavelength reader for generating wavelength signals corresponding to the scanned wavelengths, photodetectors for detecting the light intensity of a scanned wavelength, an A-D converter for converting analog signals of a scanned wavelength to digital signals, a storage device for storing data generated from the A-D converter corresponding to each wavelength, an operational circuit for processing stored data, and display devices for displaying the processed data.

Abstract: A spectrophotometer to draw time changes of a plurality of spectrophotometric data by one recording pen.

Abstract: The disclosure is directed to a spectrophotometric measuring device equipped with a plurality of channels which automatically analyze many specimens with different testing items in a short period of time for application in biochemical automatic analysis or the like.

Abstract: A system for photometric measurement of optical properties of a fluid medium utilizing multi-wavelength excitation includes a movable diffraction grating that is continuously oscillated over the spectral range of interest and a flashlamp producing high intensity, short duration flashes. The angular position of the grating at the time of a flash determines what wavelength of optical energy will be passed to the remainder of the system. Because the flash duration is brief in relation to the period of movement of the grating, the flash effectively freezes the motion of the grating allowing the high intensity output of the flashlamp to be supplied to the fluid medium, while successive flashes permit measurement at many different wavelengths in near simultaneous fashion. The system is disclosed for use in an absorbance detector for liquid chromatography.

Abstract: A method and apparatus for converting spectral and light intensity values directly to digital data, utilizes an image sensor having at least one row of sensor elements, each element including a light sensitive capacitor and an access switch and which changes state and produces a corresponding digital output signal when a predetermined charge threshold is exceeded by the capacitor whose charge is a function of light intensity of an illuminating light source. The image sensor is illuminated with a reference light source having a known intensity through a neutral density gradient filter and the digital output of the sensor is examined for the row to obtain digital data corresponding to the number of state changes in the row. The image sensor is then illuminated with an unknown light source through the filter and the digital output of the sensor for the row is examined to obtain digital data corresponding to the number of state changes in the row.

Abstract: A chopperless spectroanalytical system of the double beam type in which radiation from a common source is split into reference and analysis beams. The two beams are directed along similar paths such that the analysis beam passes through an analysis region and the reference beam bypasses that analysis region. A monochromator has two spaced aperture regions such that one aperture region provides an entrance aperture for the analysis beam and an exit aperture for a dispersed portion of the reference beam; and the other aperture region provides an entrance aperture for the reference beam and an exit aperture for a dispersed portion of the analysis beam. The beams exiting from the two exit apertures are simultaneously monitored and compared to compensate for errors due to source fluctuations and the like.

Abstract: An electro-optical system for rapid, accurate spectral analysis of the reflectivity or transmissivity of samples. A concave, holographic diffraction grating is oscillated at high speed to provide a rapid scanning of monochromatic light through a spectrum of wavelengths. The grating drive system is an electrically driven mechanical oscillator which utilizes the back EMF of the oscillator motor to maintain oscillation at the desired amplitude and frequency. A passive optical shutter mounted to the grating alternately blocks the light entering and exiting the monochrometer as the grating is oscillated. The resultant dark period is utilized by the system to provide a reference offset value and to control cooling of the detectors. A unique phase-locked loop circuit is employed to provide sample commands at precisely determined intervals to correctly correlate the spectral data with the output of the monochrometer. Source and exit optics are employed to optimally shape the light passing through the system.

Abstract: Methods for stray light measurement and compensation in spectrophotometers are disclosed. In one exemplary embodiment, stray light is determined as a convolution of a selected detected radiant power spectrum and a monochromator slit function. Such a stray light measurement may be made with or without the sample in an optical path between a source and detector within the spectrophotometer. When made with the sample in the optical path, the resulting stray light measurement may be used to compensate sample absorbance or transmittance measurements. In accordance with another embodiment of the present invention, sample absorbance or transmittance may be compensated in a method including measuring sample detected radiant power at a wavelength outside an interval of significant detected radiant power within which a sample measurement compensated for stray is desired.

Abstract: In atomic spectrophotometers comprising a source of radiation characteristic of an element to be detected in a sample, a monochromator for selecting a desired spectral line from radiation received from the source by the sample, and a detector for producing an output signal from the monochromator output radiation, the monochromator is accurately tuned to the desired line to obtain a maximum detector signal, and simultaneously, the gain of the detector is adjusted to keep the signal magnitude within the best working range of subsequent signal processing circuits. In accordance with the present invention, both adjustments are made simultaneously by comparing an amplified detector signal with a desired reference signal level corresponding to the best signal magnitude, and using the difference between them to adjust the gain of the amplified detector signal in a closed loop control system to continuously equalize the amplified detector signal with the reference level.