Abstract: The invention relates to sealable short-pathlength liquid transmission cells for Fourier-transform infrared spectroscopy applications. In exemplary embodiments, a liquid transmission cell with transmissions sections uses horizontal tubing for inserting and removing fluids from the cell. Angling the tubing relative to a top face of the cell allows small amounts of entrapped air to rise out of the optical path without blocking spectroscopy measurements. The tubing is silver-soldered to the body of the transmission cell to make a leak-free connection.

Abstract: In some embodiments, a system for detecting the presence of a contaminant on a surface includes an infrared light source configured to shine infrared light on the surface, an infrared light detector configured to detect infrared light reflected from the surface, and a computing device configured to receive an infrared reflectance signal from the infrared light detector and detect the presence of the contaminant from a feature in the reflectance signal.

Abstract: An atomizing furnace, in particular for atomic absorption spectroscopy, includes a tube furnace apparatus and a sample carrier. The sample carrier is disposed within the tube furnace apparatus, and includes at least three supporting protrusions by which the sample carrier is punctually supported on an interior wall of the tube furnace apparatus. The supporting protrusions are disposed in a common plane running through a longitudinal axis of the sample material, wherein at least two supporting protrusions are formed on respectively opposite ends of the sample carrier.

Abstract: An atomic absorption spectrometer, including: a light source combination; a detection device; a flame atomization device; a hydride generation device; a graphite furnace atomization device; and an adjustment mechanism. The flame atomization device includes a flame atomizer. The hydride generation device includes a hydride atomizer. The graphite furnace atomization device includes a graphite furnace atomizer. An axis of the flame atomizer, an axis of the hydride atomizer, and an axis of the graphite furnace atomizer are adjusted by the adjustment mechanism to coincide with an optical axis of the light source combination.

Abstract: A detecting element used for a detecting device for detecting a target substance in a sample by utilizing plasmon resonance. The detecting element includes a substrate and a plurality of metal members provided on the substrate, the metal member constituting a columnar structure and being oriented in a long axis direction thereof. The detecting element can improve sensitivity of the detecting device for detecting a target substance utilizing plasmon resonance.

Abstract: Devices and techniques for using four wave mixing in optical sensing of various materials, including isotopes, chemical and biological substances.

Abstract: The present invention has been accomplished to provide an atomic absorption spectrophotometer capable of obtaining measurement data always in the state where the lowest detection limit performance is optimized, without depending on the frequency of the power supply. In a control program which runs on the microcomputer chip 42 mounted on the atomic absorption spectrophotometer 110, a plurality of lighting periods of the light sources 11 and 12 and extraction periods of the sampling data are memorized, whose lowest detection limit performance are optimized for the frequencies (50 Hz and 60 Hz) of the AC power source for driving the AC motor 22.

Abstract: An atomic absorption spectrometer is disclosed which includes a monochromater and an optical path defined by a toric mirror, a flat mirror, a flat mirror, a flat mirror, a toric mirror, and a further toric mirror. The toric mirror directs light through entrance slit of the monochromater so that radiation is reflected from diffraction grating and out exit slit to a detector. A sample stage in the form of a furnace is located between the mirrors. The monochromater is oriented so that the entrance slit is arranged transverse to the vertical.

Abstract: A furnace, in particular for an electro thermal atomization device of an atom absorption spectrometer, has a heatable heat duct in which is mounted a trial platform. The trial platform is essentially basin-shaped with radially inward-turned rims, at least at its free ends. In order to make ongoing improvements in a furnace of the aforementioned type, so that the trial platform has an increased lifetime along with high reproducibility of measurements and simple operation as well as low cost, the trial platform features a geometric structure stabilization device which reduces the ratio of effective volume of the trial platform to the rim volume.

Abstract: An atomic absorption spectrometer is disclosed which includes a monochromater (30) and an optical path defined by a toric mirror (14), a flat mirror (16), a flat mirror (20), a flat mirror (24), a toric mirror (22) and a further toric mirror (26). The toric mirror (26) directs light through entrance slit (32) of the monochromater (30) so that radiation is reflected from diffraction grating (38) and out exit slit (40) to a detector (42). A sample stage (18) in the form of a furnace is located between the mirrors (16) and (20). The monochromater is oriented so that the entrance slit is arranged transverse to the vertical.

Abstract: At the time of measurement of a sample, before a sample is introduced into a graphite tube, signal voltages which would be detected by a photomultiplier in connection with all programmable combinations of atomizing temperatures of a graphite tube, widths of entrance and exit slits provided in a spectrometer, and wavelengths into which the light is to be decomposed by the diffraction grating are stored in memory beforehand. At the time of measurement of a sample, an amplification factor of the photomultiplier is controlled by a negative high-voltage controller according to measurement requirements, or measurement is performed after an optimum detector signal voltage is set by controlling the amplification factor of the detector signal output from an amplifier.

Abstract: A main unit, a lamp chamber, a graphite furnace analyzing section, a flame analyzing section, and a flame gas controller are sequentially placed from right to left. An autosampler is placed on the top of the lamp chamber. A housing section for a transformer and a power supply unit is provided behind the lamp chamber, the graphite furnace analyzing section, the flame analyzing section, and the flame gas controller. The housing section is used as a space for a power unit used for the whole atomic absorption spectrophotometer, as well as the graphite furnace analyzing section. The housing section is also used as space for a circuit board for controlling the whole atomic absorption photometer. The autosampler has a quadrangular sample tray. The autosampler drives an arm for holding an aspiration needle in the left and right directions and also in up and down directions.

Abstract: A furnace, in particular for an electro thermal atomization device of an atom absorption spectrometer, has a heatable heat duct in which is mounted a trial platform. The trial platform is essentially basin-shaped with radially inward-turned rims, at least at its free ends. In order to make ongoing improvements in a furnace of the aforementioned type, so that the trial platform has an increased lifetime along with high reproducibility of measurements and simple operation as well as low cost, the trial platform features a geometric structure stabilization device which reduces the ratio of effective volume of the trial platform to the rim volume.

Abstract: An atomic absorption spectrophotometer including a self reverse type hollow cathode lamp and a photomultiplier tube further includes a preliminary tester for measuring a strength of a signal L when a smaller current is supplied to the hollow cathode lamp and a strength of a signal H when a larger current is supplied while a voltage V applied between a cathode and an anode of the photomultiplier is changed. It also includes an optimal voltage detector for detecting a value V0 of the voltage V at which a super ratio U (which is defined as a ratio of a first ratio L0/H0 to a second ratio L1/H1) is closest to unity under a condition that two values V1 and V0 of the voltage V are arbitrarily chosen so that a ratio H1/H0 or a ratio L1/L0 is a predetermined value.

Abstract: At the time of measurement of a sample, before a sample is introduced into a graphite tube, signal voltages which would be detected by a photomultiplier in connection with all programmable combinations of atomizing temperatures of a graphite tube, widths of entrance and exit slits provided in a spectrometer, and wavelengths into which the light is to be decomposed by the diffraction grating are stored in memory beforehand. At the time of measurement of a sample, an amplification factor of the photomultiplier is controlled by a negative high-voltage controller according to measurement requirements, or measurement is performed after an optimum detector signal voltage is set by controlling the amplification factor of the detector signal output from an amplifier.

Abstract: An object of the present invention is to provide an atomic absorption spectrophotometer having a small installed area, in which an autosampler can be easily adjusted with a high degree of accuracy, leading to easy maintenance.

Abstract: An atomic absorption spectrometer is disclosed which includes a monochromater (30) and an optical path defined by a toric mirror (14), a flat mirror (16), a flat mirror (20), a flat mirror (24), a toric mirror (22) and a further toric mirror (26). The toric mirror (26) directs light through entrance slit (32) of the monochromater (30) so that radiation is reflected from diffraction grating (38) and out exit slit (40) to a detector (42). A sample stage (18) in the form of a furnace is located between the mirrors (16) and (20). The monochromater is oriented so that the entrance slit is arranged transverse to the vertical.

Abstract: The present invention relates to a method of testing an airbag module for a vehicle and, particularly, but not exclusively, to a method of testing an airbag module for a motor vehicle such as a car. A method of testing an airbag module is provided in which said module is tested for exposure to a given fluid, for example, water. The fluid exposure test ideally comprises the step of inspecting said airbag module or a swab taken therefrom by means of Atomic Absorption Spectroscopy techniques. The present invention thereby provides a testing method sufficiently rigorous to identify fluid damage potentially suffered by a previously installed airbag module during its service life.

Abstract: A spectrometer or multiple wavelength absorbance detection method and apparatus providing improved accuracy for an array of measurements at different wavelengths. The spectrometer utilizes a multiple wavelength illumination system with an array of independent detectors with different pathlength cells, where each cell is illuminated with predominately monochromatic light after separation by a light dispersing element. Each sample cell has an optical pathlength, optics and photodetection device that are optimized for its particular wavelength to accurately measure absorbance through an expected substance.

Abstract: The present invention relates to a thermoelectrical furnace for an atomic absorption spectrometer for converting a sample to be analyzed into the atomized state, the furnace comprising a first hollow furnace part connected to a first pair of electrodes and including a first opening for introducing the sample, and a second hollow furnace part connected to a second pair of electrodes and including a second opening for introducing the sample.

Abstract: Atomizing device for atomic absorption spectroscopy according to the Zeeman method, wherein a tubular atomizing furnace which is transversely heated via wings and with horizontally oriented furnace tube is located with its furnace wings between vertically arranged electrodes for examination of liquid specimens fed from the top and for examination of solid specimens fed from the side, and the vertically oriented atomizing furnace is located laterally between magnetic poles.

Abstract: The present invention pertains to the construction of analytic instruments and can be used for analyzing natural and industrial water, biological samples, geological samples and air. The purpose of this invention is to reduce substantially the power used by the atomizer and the analyzer, and to increase the number of objects that can be analyzed. To this end, the method for the thermionic atomization of a sample involves carrying out an ionic sputtering of the sample from the cathode in a low-pressure discharge. The cathode is heated by the discharge to a temperature of between 800 and 1400° C., while the ballast gas consists of Kr or Xe under a gas pressure of 10 to 15 torrs. The thermionic atomization device includes an atomizer arranged in a gas-discharge chamber filled with an inert gas. The atomizer is made in the form of a hollow, cylindrical, metallic and thin-wall cathode.

Abstract: A furnace, in particular for an electro thermal atomization device of an atom absorption spectrometer, has a heatable heat duct in which is mounted a trial platform. The trial platform is essentially basin-shaped with radially inward-turned rims, at least at its free ends.

Abstract: In an atomic absorption photometer, depending on a fact whether a background correction is carried out or not, a pattern of a pulse lighting of light sources and a timing of sampling a light receiving signal are changed. Namely, at the time of a background correction measurement, one cycle is divided into three periods, that is, a period of lighting HCL, a period of lighting D2L, and an off period, and at the time of a measurement without a background correction, one cycle is divided into the period of lighting HCL and the off period. Accordingly, at the time of the measurement without the background correction, the period of lighting HCL and the off period become longer, and signal-to-noise ratio of the light receiving signal is improved. Accordingly, an absorbance with high accuracy can be calculated.

Abstract: The present invention refers to a method for atomic absorption spectroscopy of an analyte which is contained in a sample to be analyzed and which is converted into free atoms in an absorption volume of an atomizer, said method comprising the steps of (a) position- and time-dependent measuring of the atomic absorption over the cross-section of the absorption volume and (b) simultaneous determination of surface temperatures of the atomizer.

Abstract: A furnace-type atomic absorption spectrophotometer heats a sample by controlling a heating current passed to the tube inside which the sample is held. The temperature of the tube is monitored and the heating current is controlled, say, by a phase control method, such that the monitored temperature will approach a specified target temperature. The spectrophotometer includes a control unit which determines a quantity of a specified operation for the heating control such as a firing angle by a PID control calculation on the difference between the monitored temperature and a target temperature value. PID parameters are determined such that the minimum detectable quantity can be reduced.

Abstract: The invention relates to an atomic absorption spectrometer, comprising a measuring light path leading from at least one light source emitting line radiation corresponding to at least one element to be detected, through an atomization means for atomizing a sample containing the element to be detected, to a detection means, and a reference light path leading from each light source to the detection means. The invention is characterized in that a beam splitting means is provided such that a first component of the line radiation of each light source is guidable via the measuring light path and a second component of the line radiation of each light source is simultaneously guidable via the reference light path.

Abstract: Devices and techniques for performing highly-sensitive spectroscopic measurements in a sample vapor by using a four-wave-mixing optical system and an atomizer chamber. One embodiment of a spectrometer comprises a gas-phase atomizer having an atomizer chamber operable to vaporize a sample solution to produce a sample vapor, first and second alignment templates having apertures to align a probe beam, first and second pump beams to form a four-wave mixing configuration, a laser tunable to generate a laser beam at a desired wavelength corresponding to an absorption line in the sample vapor, and a set of optical elements disposed relative to the laser and the atomizer to split the laser beam into the probe beam, the first pump beam, and the second pump beam. The probe beam, the first and second pump beams are directed to overlap with one another in the sample vapor to produce a signal beam through a four-wave mixing process.

Abstract: An atomic absorption spectrophotometer possessing an electrical heating unit which includes a graphite tube for atomizing a sample by heating the sample; a light emitting unit for emitting measuring light and irradiating the atomized sample with the measuring light; a spectroscope unit for diffracting the measuring light passing the electrical heating unit and selecting the required wavelength component; a detection unit for detecting the quantity of the required wavelength component selected by the spectroscope unit; an input unit to input at least one of the wavelengths of the required wavelength component and the required heating temperature of the electrical heating unit; and a control unit for controlling the above units, which comprises a shading device provided at the propagation axis of the measuring light between the electrical heating unit and the detection unit, and which possesses a light transmitting unit, for restricting the quantity of the measuring light passing the electrical heating unit, wi

Abstract: An electrically heatable hollow-body furnace with a secondary surface on which an analyte of a sample can be condensed prior to being atomized. The furnace is constructed in two sections which are capable of being electrically heated independently of one another. The secondary surface is defined by a surface of one of the sections. A process for atomizing an analyte of a sample to be examined, utilizing the device according to the following steps: introducing the sample into a hollow-body furnace having a secondary surface, condensing the analyte on the secondary surface and atomizing the analyte.

Abstract: The object of this invention is to provide an atomic absorptiometer and a metal specimen atomic vapor generation apparatus used in the atomic absorptiometer, which enable a light absorption measurement based on the Zeeman effect highly capable of background correction and eliminate the need for the troublesome work of dismounting a magnet. For this purpose, the following configuration is employed. First, the specimen, hydrochloric acid, and sodium borohydride are delivered and mixed by the peristaltic pump 10 to produce a metallic hydride. The generated gas-liquid mixture solution is separated by the separator 12 into a specimen gas and liquids. The separated specimen gas is introduced into the heating section 30. Electricity is supplied from the power source 28 to the specimen heating section 30 where the specimen gas introduced is heated and separated into hydrogen and a specimen metal vapor to be measured.

Abstract: A transversely or longitudinally heated atomizing furnace for flameless atomic absorption spectrometry. The atomizing furnace has a tube furnace segment and a specimen support disposed in the tube furnace segment. The specimen support is rigidly fixed in the tube furnace. For that purpose, the specimen support has on its underside a central peg or foot which is fixed in a complementary depression or recess formed centrally in the inner wall of the tube furnace, approximately opposite the sample insertion opening. The specimen support and the tube furnace segment are formed from electrographite. The gas-accessible surfaces of the specimen support and the tube furnace segment are coated with pyrocarbon. The two members are non-detachably connected to each other by means of the pyrocarbon coating. The specimen support extends over as large as possible a portion of the length of the tube furnace. On its upper side, the specimen support is formed with a trough that can receive up to 50 .mu.

Abstract: In a method of determining concentrations by means of atomic absorption spectrometry, the absorption of structured background is determined in a graphite furnace.

Abstract: An electrically heatable hollow-body furnace with a secondary surface on which an analyte of a sample can be condensed prior to being atomized. The furnace is constructed in two sections which are capable of being electrically heated independently of one another. The secondary surface is defined by a surface of one of the sections. A process for atomizing an analyte of a sample to be examined, utilizing the device according to the following steps: introducing the sample into a hollow-body furnace having a secondary surface, condensing the analyte on the secondary surface and atomizing the analyte.

Abstract: The invention relates to optical instrment engineering. It is suggested that a linear solid state detector (photodiode array detector, charge coupled device, charge transfer device) that is positioned along the image of entrance slit of the monochrometer be used in an atomic absorption spectrophotometer. This will improve the analytical performance of an atomic absorption spectrophotometer--lower the detection limits, extend the range of concentrations to be measured, increase the reproducibility of measurements by taking into account the temporal and spatial non-uniformities of the analyte distribution over the atomizer volume and will simultaneously provide atomizer walls and of the platform temperatures.

Abstract: The invention intends to provide an atomic absorption spectrophotometer which can establish a uniform heat distribution during heating of a sample and can improve analysis accuracy and analyzing efficiency. For this purpose, a graphite tube type cuvette mounted in a graphite atomizer furnace for an atomic absorption spectrophotometer comprises a large-diameter portion for retaining a sample in place, a small-diameter portion connected to the large-diameter portion and having a smaller diameter than the large-diameter portion, and a step portion for demarcating between the large-diameter portion and the small-diameter portion. The graphite tube type cuvette is formed such that its cross-sectional area in a plane perpendicular to the direction of passage of an electric current supplied to the cuvette is the same in any of the large-diameter portion, the small-diameter portion and the step portion. The amount of resistance heat is thereby also the same in any portions.

Abstract: A light beam emitted by a hollow cathode lamp is concentrated on a central portion of an electrothermal sample atomizing apparatus by a concave mirror. The light concentrated on the central portion of the electrothermal sample atomizing apparatus is further concentrated on a central portion of a flame produced in a burner type sample atomizing apparatus by a lens. The light traveled through the burner type sample atomizing apparatus is condensed by a concave mirror, reflected by a flat mirror, and concentrated on an entrance slit of a spectroscope. Light outgoing through an exit slit of the spectroscope is detected by a photodetector.

Abstract: A control system is disclosed that controls the position of a grading implement of a construction machine according to a site plan. The control system has three basic components: a stationary tracking station, a computer connected to the tracking station, and an implement controller attached to the construction machine. The tracking station measures a distance and an azimuth (horizontal) angle to a remote target located on the construction machine and communicates that position information to the computer. The computer consults a stored site plan to determine what elevation is desired at that position and calculates a corresponding zenith (vertical) angle, and communicates the desired zenith angle to the tracking station. The tracking station in turn positions a zenith-reference laser beam at the desired zenith angle. The implement controller senses the zenith-reference laser beam and adjusts the grading implement relative to the zenith-reference laser beam until its desired position is obtained.

Abstract: A system and method for automatically controlling the position of a work implement movably connected to a work machine and maintaining the work implement at a preselected slope of cut relative to a geographic surface is provided. The system has first and second receiving devices mounted on the work implement for receiving position signals from a plurality of remote locations. A processor determines the actual slope of cut of the work implement based on the received position signals. An implement controller delivers an implement control signal in response to a difference between the actual and a preselected desired slope of cut of the work implement. An implement control system elevationally changes the slope of cut of the work implement at an automatic mode of operation of the system. The system is particularly suited for use on a geographic surface altering work machine.

Abstract: The invention relates to optical instrment engineering. It is suggested that a liner solid state detector (photodiode array detector, charge coupled device, charge transfer device) that is positioned along the image of entrance slit of the monochrometer be used in an atomic absorption spectrophotometer. This will improve the analytical performance of an atomic absorption spectrophotometer--lower the detection limits, extend the range of concentrations to be measured, increase the reproducibility of measurements by taking into account the temporal and spatial non-uniformities of the analyte distribution over the atomizer volume and will simultaneously provide atomizer walls and of the platform temperatures.

Abstract: A first light receiving portion and a second light receiving portion are provided on the upper surface of a moving body having driving wheels at an interval of a prescribed distance in a plane. The first light receiving portion and the second light receiving portion rotate around the axis in the vertical direction. On the other hand, a first light emitting portion and a second light emitting portion are provided on the side face of a station serving as a reference station at an interval of a prescribed distance in a plane. The first and second light receiving portions carry out sampling while rotating, so that the quantity of light reception is changed according to the directivities of the first and second light receiving portions. When the peaks of the directivities of the first and second light receiving portions match the direction of the first light emitting portion or the second light emitting portion, the quantity of light reception is maximized.

Abstract: Method and apparatus for determining the position of a mobile vehicle with a receiver, through a triangulation based on angular data obtained by processing directive electromagnetic signals emitted by fixed rotating transmitters. The method includes: dividing the 360.degree. of the rotation into 2.sup.n angular values; generating a coding sequence of 2.sup.n binary configurations made up of 2.sup.n +(n-1) bits; generating a coding pattern wherein said angular values are coded; storing said coding pattern in the transmitters and in the receiver; starting the rotations of the two transmitters at a correlated, constant speed; transmitting the angular data corresponding to the direction of emission of the beams; demodulating the signals detected by the receiver and obtaining the coded angular values; and calculating the vehicle position by using the latest mean angular values obtained from the signals.

Abstract: A simultaneous multi-element atomic absorption spectrometry system includes a light source, a furnace, a spectrometer, and a random access charge transfer device. The furnace creates vapors of a sample contained within the furnace. The light source passes a light beam through the furnace so that wavelengths of the light beam corresponding to spectral lines of multiple elements contained in the vapors are absorbed by the vapors. The spectrometer receives the light beam after the light beam has passed through the furnace, and disperses the light beam into a spectrum. The random access charge transfer device receives the light beam after the light beam has passed through the spectrometer, integrates and stores charge corresponding to the intensity of the light beam, and randomly accesses for readout subarrays of the random access charge transfer device corresponding to spectral lines of the multiple elements.

Abstract: System and method for temperature resolved molecular emission spectroscopy of solid, liquid or gaseous materials are described wherein a sample is vaporized and decomposed, and the vaporous sample is transported into a combustion flame; a spectrum of intensity of the optical emission from the flame at a selected wavelength versus temperature of the sample define molecular peaks which are characteristic of the sample material and allows both qualitative and quantitative analysis of the sample.

Abstract: Apparatus and method for rapid detection of explosives residue from the deflagration signature thereof. A property inherent to most explosives is their stickiness, resulting in a strong tendency of explosive particulate to contaminate the environment of a bulk explosive. An apparatus for collection of residue particulate, burning the collected particulate, and measurement of the optical emission produced thereby is described. The present invention can be utilized for real-time screening of personnel, cars, packages, suspected devices, etc., and provides an inexpensive, portable, and noninvasive means for detecting explosives.

Abstract: The invention relates to a multielement atomic absorption spectrometer for simultaneously performing measurements for determining both one element and a plurality of elements under optimum conditions. The atomic absorption spectrometer comprises at least two lamps respectively emitting lines of at least one analyte element, a furnace heating the analyte sample into its atomized state, at least one optical dispersion element having an entrance slit arranged upstream thereof, detector elements, as well as means for passing radiation emanating from the lamps through the furnace, through the entrance slit and the dispersion element to the detector elements, and measuring means.

Abstract: A system for measuring the wheel base of an automobile frame and the transverse and longitudinal offsets of its steered wheels which comprises a first device and a second device to be applied by known means to two automobile frame wheels positioned on the same side, said first device comprising two light emitting diodes (LEDs) located a known distance (d) apart, measured in the horizontal plane, and said second device comprising optical angle measurement means arranged to measure the angle (.alpha.) subtended between the light rays emitted by said light emitting diodes.

Abstract: Improved transmitter and receiver units for use in spatial measurement system that are easy and inexpensive to manufacture while providing a high degree of reliability are disclosed. Specifically, the laser transmitter includes a laser emitter, a bearing/motor assembly coupled to the laser emitter, the bearing/motor assembly including a rotatable hollow spindle shaft through which a laser beam generated by the laser emitter passes and a motor for driving the spindle shaft, a prism assembly coupled to the spindle shaft, wherein the prism assembly divides the laser beam generated by the laser emitter into a pair of fanned laser beams, and reflecting means for reflecting the fanned laser beams generated by the prism assembly as counter-rotating fanned laser beams. The receiver unit preferably includes at least one optical receiver coupled to an extension member, a processing unit coupled to the optical receiver, and a receiver interface coupled to the processing unit.

Abstract: A spectroscopic apparatus applicable to both ICP (inductively coupled plasma) emission spectroscopy and atomic absorption spectrometry is provided. The spectroscopic apparatus includes a sample unit on which a plasma torch for ICP emission spectroscopy and a heating tube for atomic absorption spectrometry are mounted. A control unit shifts the sample unit to place a plasma flame that is on an end of the plasma torch in front of the light inlet of a spectroscopic unit when the apparatus is operating in the ICP emission spectroscopic mode and to place a central axis of the heating tube in front of the light inlet when the apparatus is operating in the atomic absorption spectrometric mode. The control unit also shifts the apparatus to a two stage spectral mode for ICP emission spectroscopy and to a one stage spectral mode for atomic absorption spectrometry.

Abstract: In an atomic absorption spectrophotometer utilizing the direct Zeeman's method, plural lamps are installed in the light source unit in order to enhance the versatility and enable continuous analyses. Accordingly, a plurality of low pressure discharge tubes 14 and hollow cathode lamps 16 in total are mounted on a lamp holder 12 of the light source unit, and by rotating the lamp holder 12, an arbitrary lamp may be positioned at the light source position for measurement. When the low pressure discharge tube 14 is used as the light source, in order to perform background correction by the Zeeman's method, a permanent magnet or an electromagnet 24 for operating a magnetic field on the light source is disposed, and a polarizing unit 26 is disposed on the measurement optical path, so that the direction of polarization of the measurement light to be sent to an atomizing unit 26 is changed over between the atomic absorption measurement mode and the background correction mode.