Abstract: A method of identifying an operating position of a multiple-position filter changing mechanism situated in an optical path of a spectrophotometer by detecting and measuring a spectral characteristic(s) of light passed along the optical path to the spectrophotometer detector for one or more operating positions of the filter mechanism and comparing the measured spectral characteristic(s) with stored spectral characteristic information for one or more operating positions of the filter mechanism.
Abstract: This invention relates to an apparatus for calibrating a slit width among calibrating apparatuses in a monochromator.There has been the problem that, although the slit width precision of the monochromator has been an important performance item, the calibration of the slit width has not hitherto been performed.This invention employs a bright-line spectrum or zero-order light for the slit width calibration. A peak is found out from among output signals of a lightdetector (20) by means of a peak decision unit (26). The peak value is stored into a memory (28). This peak value and the output of the lightdetector (20) are compared by a comparator (32). The slit width is calibrated on the basis of the quantity of wavelength scanning till the coincidence of both the values.
Abstract: A spectrophotometer system has an optical system for transmitting a beam from a source at select wavelengths onto a detector. A plurality of filters are positioned in a tray. A stepper mechanism indexes the tray along a path. A microcomputer controls the stepper mechanism and the optical system. The wavelength is successively changed over a range, the tray is indexed to move a select filter into the beam at a predetermined wavelength and the changing is discontinued during indexing.
Type:
Grant
Filed:
March 7, 1980
Date of Patent:
August 3, 1982
Assignee:
The Perkin-Elmer Corporation
Inventors:
Morteza M. Chamran, Larkin B. Scott, Paul B. Williams
Abstract: At least one of the entrance slit and the exit slit of a monochromator is capable of being opened or closed. The light issued from the exit slit when the slit width is changed is detected by a light detector. The slit width is calibrated when the ratio between the maximum value of the output of the light detector and the output of the light detector with the slit being gradually closed subsequently reaches a predetermined value, in other words, when a predetermined narrowness of the slit is attained. The slit width is controlled by a pulse motor or the like. The pulses supplied to the pulse motor are counted by a counter. At the time of slit width calibration, a value corresponding to the particular slit width is set in the counter, thus performing the slit width calibration.
Abstract: A microprocessor based spectrophotometer including manual keyboard command for sequencing a monochromatic energy beam through a spectral range of wave-lengths to a keyboard selected wavelength. A manual adjustment knob is thereafter rotatable for generating a 4-bit gray code signal which successively changes as the adjustment knob is rotated. The microcomputer senses a change in the gray code signal and indexes (steps) the wavelength of the monochromatic beam in proportion to the positional change of the adjustment knob as indicated by the changing gray code. A visual display indicating wavelength setting and spectral response, is updated conjointly with manual wavelength adjustment.
Type:
Grant
Filed:
March 7, 1980
Date of Patent:
March 9, 1982
Assignee:
The Perkin-Elmer Corporation
Inventors:
Morteza M. Chamran, Larkin B. Scott, Paul B. Williams
Abstract: The invention relates to a spectrometer including a rotatable dispersive element, a stepping motor for varying the angular position of said dispersive element, a program transmitter for controlling said stepping motor, a timing generator and a recording instrument.
Abstract: A spectrophotometer utilizing a multiple wavelength electromagnetic wave source which is intercepted and dispersed into a spectrum. The spectrophotometer includes a closed loop servo positioning mechanism for simultaneously directing selected portions of the electromagnetic spectrum to a detector which analyzes these portions of the spectrum for analytical purposes.
Type:
Grant
Filed:
March 20, 1978
Date of Patent:
July 8, 1980
Assignee:
Altex Scientific, Inc.
Inventors:
Haakon T. Magnussen, Jr., Roy P. Moeller
Abstract: A wavelength reading apparatus for a monochromator comprises a monochromator utilizing a dispersion element for dispersing light in accordance with its wavelengths, a dispersion element driver unit for rotating the dispersion element to effect the tuning wavelength scanning operation of the monochromator and a wavelength counter for adding or subtracting a pulse, which is produced each time when the tuning wavelength of the monochromator changes by a predetermined wavelength increment, depending on whether the wavelength increases or decreases. The wavelength counter is set to a predetermined counting value, in response to a wavelength calibrating pulse produced when the tuning wavelength of the monochromator reaches a predetermined value, so that any counting value of the wavelength counter correctly represents the instant value of the tuning wavelength of the monochromator.
Type:
Grant
Filed:
May 8, 1979
Date of Patent:
May 20, 1980
Assignee:
Hitachi, Ltd.
Inventors:
Yoshio Maeda, Koichi Matsumoto, Koji Nishiwaki
Abstract: A monochromator for the simultaneous selection and utilization of two wavelengths of small and constant band width, whereby the wavelengths may be selected and rapidly changed as desired. The monochromator is particularly suitable for the simultaneous scanning of a chromatogram (e.g. a thin-layer chromatogram) with two wavelengths to determine the concentration of a certain material independently of disturbing influences of the matrix. This is done by photosensors which are adapted to be led on pivot arms on a circular arc about the element dispersing the light.
Type:
Grant
Filed:
February 3, 1977
Date of Patent:
February 20, 1979
Assignee:
CAMAG Chemie-Erzeugnisse und Adsorptionstechnik AG