Abstract: A spectrophotometer of the type using a pulse motor to rotate a diffraction grating through a speed reducing mechanism has a capability of constructing a conversion table according to a program, by which table a rotation amount of the motor is converted to a corresponding wavelength of output light from a monochromator. The spectrophotometer is capable of designating a calibration mode in which an emission peak at a known wavelength of light from a light source is detected, a coefficient in a conversion equation is determined on the basis of the known wavelength of the emission peak and a rotation amount of the motor at a time when the emission peak is detected, and the determined coefficient is used to construct the conversion table which is then stored in a nonvolatile memory. In an analysis mode, a rotation amount of the motor is converted to a corresponding wavelength in accordance with the conversion table in the nonvolatile memory.

Abstract: A spectrophotometer including: a) a light source switching mechanism for switching a plurality of light sources by swinging a light source mirror; b) a filter selecting mechanism; c) a diffraction grating rotating mechanism; and d) a controller for determining the operation origins of the three driving mechanisms using a rough origin sensor provided for the diffraction grating rotating mechanism and a photometer. The operation of the controller is to: i) determine an origin of the movement of the filter by making an end of the filter frame to touch a stopper; ii) determine a rough origin of the diffraction grating using the rough origin sensor; and iii) determine an origin of the movement of the light source mirror and a precise origin of the movement of the diffraction grating by detecting the position at which the photometer detects the maximum intensity of light.

Abstract: A spectrophotometer provided with: a sample changer for holding a plurality of samples to be analyzed, each of which is given an identification code, and positioning a selected one of the samples for measurement; means for setting a measuring wavelength for each of the identification codes of the samples; means for setting an identification code for the measured data of each of the samples; means for setting a coefficient to be used for processing the measured data of each of the samples together with an identification code; means for setting an operation expression composed of the identification codes of the measured data of the samples and the identification code of the coefficient; means for storing the data obtained by measuring each of the samples with the corresponding one of the wavelengths set for the sample held by the sample changer in correspondence with the corresponding one of the identification codes of the measured data; and means for reading out the data stored in the storing means and the coe

Abstract: A spectrophotometer comprising a light source, a spectroscope which separates the light of light source depending on the wavelengths, chops the light into the first and second light beams and allows the light beams to pass through the reference cell and sample cell, a photodiode which alternately receives the light beams from the reference cell and sample cell, a variable gain amplifier which amplifies a light current of photodiode, an A/D converter which converts and guides the reference output and sample output as the digital values synchronously with the chopping period, and a again setter which sets the gain of the variable gain amplifier depending on the reference output value from the A/D converter.

Abstract: A spectrophotometer wherein the diffraction grating is driven directly by a pulse motor and the wavelength of the monochromatic light used for measurement is calculated by a data processor from the amount of rotation of the pulse motor. The data processor is provided with an input unit for setting a parameter corresponding to the difference between the nominal and actual grating constants of the diffraction grating and so arranged as to calculate the wavelength in accordance with the nominal grating constant having been modified with the parameter set through the input unit.

Abstract: An improved photosensitive material for electrophotography, said material comprising a mixture of a polyvinylcarbazole or a derivative thereof together with a sensitizing dye consisting of certain alkyl substituted indocyanine derivates, particularly the perchlorates.

Abstract: A method for forming a color image includes a step of spraying three kinds of photoconductive toners with a sensitization wavelength band different from its absorption wavelength band, a step of electrically charging these different toners, a step of exposing these sprayed and electrically charged photoconductive toners to light for selectively removing electrostatic charges, and a step of removing the toners freed of electrostatic charges from the substrate. The magenta color photoconductive toners sensitive to red light, yellow color photoconductive toners sensitive to green light, and the cyan color photoconductive toners sensitive to blue light, are used as aforementioned three kinds of photoconductive colors.

Abstract: A spectrophotometer system including a monochrometer which scans a sample in a sample cell with discrete wavelengths of light, and measures intensity signals of at least two discrete wavelengths of light emitted from the sample. These measured intensity signals are base-line corrected by a computer with respect to reference intensity signals at corresponding wavelengths. The computer also calculates base-line corrected intensity signals for wavelengths of light intermediate said two wavelengths of light from the intensity signals of said two respective discrete wavelengths. All base-line corrected intensity signals are stored for analysis of the sample.

Abstract: A spectrophotometer comprising means for producing electrical signals Er and Es corresponding to reference and measuring beams, respectively; means for multiplying the value Es by a factor k to produce an electrical signal corresponding to the value kEs; means for controlling said signal producing means so as to keep the value (Er + kEs) constant; and means for producing an electrical signal corresponding to the value (Er - kEs), whereby minute changes of the absorbance of a sample can be accurately measured without logarithmic conversion.