JPS60237346A - Method and device for analyzing polyelement - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for multi-element analysis, in particular radiation spectral analysis, multi-channel atomic absorption analysis or spectrometry, which selects various spectral lines or bands from the overall spectrum. Concerning what is used in Photometries 1 to 3.

11 Conventional equipment for multi-element radiation analysis generally includes equipment for thermal or non-thermal excitation of each element contained in the sample material, which a line or excitation source;
It includes an optical imaging system, an optical dispersion system, an optical system for selecting various spectral lines, several charging detectors, and an electronic detection system.

The selection of the spectral lines is performed by several exit slits, and the selected light is transmitted to each detector by optical elements, such as prisms, reflectors and optical cables.

In the case of these known Im, it is necessary to install as many detectors as there are elements contained in the sample material to be analyzed, or to identify only the spectral lines for a particular sample quality. The disadvantage is that a large number of spectral lines are selected by means of optical means which are irreplaceably arranged.

In the first case, a large number of detectors and detection channels are provided, which are not always necessary for the analysis of each sample. In the latter case, only a small number of detectors are used, but special optics are required for selection for different sample materials, which makes the device expensive.

The excitation of spectral lines of individual elements depends on temperature or electron density. Since the excited volume of the radiation source is spatially limited due to the relatively cool surroundings, all radiation sources exhibit more or less strong inhomogeneities. Spectral lines with different excitation energies are therefore optimally excited at different locations of the radiation source. The same effect occurs when the electron density is non-uniform.

Such a relationship becomes particularly difficult when ICP (M-conducting coupled plasma) is used as an excitation source. In this case, the optimal excitation zones for ablating individual elements may be separated by up to 20 mm.

Sequentially operated spectrometers using ICP-excitation (commonly referred to as plasma spectrometers) therefore use an optically dispersive system (D) as their excitation source.

S) often equipped with a device for imaging into
This is preprogrammed and controlled by the microprocessor in response to a spectral line set at its DO8, allowing it to capture portions of the plasma that are favorable for this spectral line.

Simultaneously operated spectrometers do not include such devices. These spectrometers can capture only one point within the excitation source and therefore cannot provide the detection performance of the sequential spectrometers described above.

Only a small amount of sample material can be used, and for this purpose the pulsed radiation of the excitation source is carried out by injection of the sample or by laser kit atomization, or alternatively the sample material is subjected to arc atomization. In cases where continuous atomization is not possible or only very short sampling times can be used for a large number of elements, successive selection of optimal excitation regions has negative effects.

In addition to the dependence of the spectral line radiation on the imaging position, for each spectral line there is a further dependence on the power consumption of the excitation source and the flow rate of the carrier gas for the sample material sprayed in the form of an aerosol. There are various inherent dependencies, such as the strength of the radiation (referred to as intensity).

In such cases, direct or indirect proportionality may hold, or a local maximum may be followed.

In the case of known sequential spectrometers, the dependence on the power consumption is taken into account only to the extent that it is programmed for each spectral line. This allows, in the case of an ICP sequential spectrometer, to examine a single spectral line as it arrives, to image the part of the optimum excitation position (called the optimum observation height), and At the same time, it becomes possible to adjust the amount of power consumption VR most suitable for this spectral line.

In the case described above, the observation height, power consumption and carrier gas flow rate have to be made individually for each spectral line to be recorded, and the principle of this sequential operation is therefore A disadvantage is that it requires a very constant excitation source that emits radiation. In addition, the total measurement time increases significantly.

In the case of spectrometers with simultaneous operation, the known techniques have to operate with so-called compromise conditions for the adjustment of the respective measurement index values. This does not necessarily mean that the best possible analytical performance for all spectral lines will be achieved.

The aim of the invention is to obviate the drawbacks as mentioned above.

Another object of the invention is to provide a measuring device for detecting multiple spectral lines or bands simultaneously, increasing analytical efficiency.

Another object of the invention is to provide a measuring device with which samples can be tested simultaneously in a significantly shorter measuring time and at lower costs.

Another object of the present invention is to provide a method for detecting a plurality of spectral lines or bands simultaneously, with each detector using only a single optically dispersive member. It is an object of the present invention to provide an apparatus for analyzing sample materials that allows selective setting of power consumption and carrier gas flow rate.

The purpose of the above and other objects is to provide a multi-element analyzer for a sample material with a plurality of light exit slits such as those used to select out only a number of spectral lines comprising the entire spectrum; This is achieved by means of a device, each of which is combined with at least one optical cable. Each optical cable can be connected via its end to a telescoping unit which is divided into several sections.

Each of these sections is associated with detector means, which are also coupled with evaluation electronics.

According to the invention, a mask is inserted between said telescoping unit and the detector means, said mask having at least one or more slits optically connecting each detector means with a particular part of their section. It is equipped with

for displacing said inset unit relative to the mask in a plane that is substantially parallel to both said inset unit and the plane defined by the detection surfaces of their detectors; Means are in place. The fitting unit is provided with a coding mark which determines the optical coupling of the position of the fitting of each optical cable into the fitting unit relative to the detector.

A microprocessor is provided, which is coupled to adjustment means for adjusting the at least one measurement index value and to a signal detector associated with the coding mark.

Preselected values for at least one measurement index value are stored in the microprocessor for each combination thereof.

Each of the sections has at least one row of holes for a corresponding optical cable.

At least one of the fitting holes in each section is optically coupled to one of the detectors through the mask.

Yet another object of the invention is to provide a method for multi-element analysis in which spectral lines or bands from a radiation source are directed to each detector via the optical cable.

Each optical cable carrying a spectral line or band for which the same or similar metric value is required is assembled to form several groups, each optically substantially combined with a corresponding detector. .

The measurement index values to be set can be optimized for the device as a whole or for groups of spectral lines, which increases the measurement efficiency and reduces the measurement time.

With the device according to the invention it is possible to simultaneously evaluate as many spectral lines as there are provided detectors.

Each cable associated with an exit slit can be selectively coupled to a different section of the inset unit, so that the spectral lines can be measured by stepwise displacement of the inset unit relative to the mask. The number of will increase. The hibernation recesses then pass through the openings in the mask in turn. The number of spectral lines to be detected is equal to the number of possible displacement positions, which corresponds to the number of fitting holes provided in each section, multiplied by the number of detectors. In order to increase the spectral light intensity of the elements to be analyzed, further rows of inset holes are provided in each section of the inset unit parallel to the first row, the number - Each hole in a row is adjacent to each hole in another row.

These adjacent holes allow the insertion of further optical cables, which are combined with other spectral lines of the same element to be analyzed.

In this way, - detectors simultaneously detect spectral light from several spectral lines of the element to be analyzed, which light passes through an aperture in the mask.

The aperture is configured to optically couple each adjacent socket hole of a different row of sockets simultaneously to one detector.

Advantageously, the displacement of the inset unit relative to the mask is combined with a change in the amplification factor of the individual detection channels as well as a change in the integral value of the electronic signal in the evaluation electronics coupled to these detectors. It is good that it is done.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be more easily understood, reference will now be made to the accompanying drawings, in which one embodiment of the invention is shown diagrammatically and by way of example.

Following an optical dispersion system or dispersion means 1, such as a diffraction grating spectrometer, in the direction of light propagation of the radiation @ 17, there is a mask 2, which is connected to an optical cable 4 (only a part of which is shown). (only the mask 2 is shown) combined with a block 3 containing an array of light entrance surfaces 4' (not shown). Each light inlet 4 is associated with a correspondingly located exit slit (not shown) of the array (2) of light exit slits. One end portion of the optical cable 4 is fixed to the block 3 in some suitable manner. The light entrance surface 4' of the optical cable 4 lies in a plane that faces the mask 2 and includes the surface of the block 3. Each exit slit of this mask 2 is arranged in such a way as to allow the selection of a respective spectral line, i.e. each exit slit of the output face of the grating 1 (
(not shown) with corresponding spectral lines. A fitting unit 9, a mask 7 and a detector unit 5 are arranged one after another in respective parallel planes with a small relative spacing from each other. The telescoping unit 9 is provided with a plurality of holes 11, which allow the other ends of the optical cables 4 to be inserted therein, thereby allowing the respective optical exit faces 4'' of these optical cables 4 to be inserted.
(when they are inserted) they will be facing the mask 7.

The telescoping unit 9 is a substantially flat rectangular plate which is subdivided into sections 8 (six in the case of the peg embodiment) of equal size and shape. Means 10' and a servo motor 10 are provided for displacing the fitting unit 9 parallel to the plane of the mask 7 in the direction indicated by the front arrow Δ.

Each of the sections 8 has several inset holes 11 in two parallel rows, which are arranged symmetrically to each other in the two coordinate directions. Therefore, these fitting holes 11 are △
Along six parallel rows marked thru F, and along a to j
They are lined up along the 10 columns shown by . The detector unit 5 consists of a plurality of photodetecting means 6 (six photodetectors in the case of this specific example), which correspond to at least one of the overlapping fitting units 9. The hole 11 is optically covered. The mask 7 has six slits 12 which are arranged along two parallel lines, but which lines are also perpendicular to and perpendicular to the respective row A to F of each hole 11. They are arranged parallel to the columns a to j formed by the holes 11 in adjacent rows.

Each of the six slits 12 is associated with a corresponding section 8. In this way, each particular hole 11 of each adjacent section 8 of the telescoping unit 9 is operatively coupled via their slit 12 to a respective photodetector 6.

The detector unit 5 is connected via lines not shown to an electronic evaluation device 13 comprising a plurality of evaluation channels. Optical cables 41 that are not required for the analysis of a particular sample material are kept in the spare 14 of the telescoping unit. Two rows of fitting holes 11 (for example, AS, CD,
EF, etc.) in parallel in one of the corresponding sections 8 allows an increase in the intensity of the spectral lines emitted by the element to be analyzed. That is, for example, if there is another one in the adjacent fitting hole 11 in the next row,
Insert the optical cable 4. Of course, this further optical cable 4 is in this case subordinated to one spectral line of the same element to be analyzed.

At the end of the telescoping unit 9 there is a mark indicating which of the five columns, i.e. "j to j and a to e, is operatively connected to the lower photocell 6 via the slit 12". position indicator 15.

This position indicator 15 consists of a reflective coding mark or a respective slit, which is sampled by a correspondingly arranged signal detector 16. In the latter case, a light source (not shown) is fitted into the unit 9.
is arranged so as to illuminate the coding mark (15) adjacent to the bottom surface of the code mark (15).

A radiation bundle 17 is emitted from a radiation source 21, which is an ICP (inductively coupled plasma) in a discharge tube 22.
, which is surrounded by an induction coil or wire 23. A carrier gas tube 24 opens into the interior of the discharge tube 22 .

A high frequency generator 25 supplies the necessary electrical energy to the induction coil 23 via line 25', and this generator
26'' to a power control device 26.

A measurement pick-up device 27 is also coupled to the high-frequency generator 25 via a line 21' for detecting the generated electrical energy.

The radiation bundle 17 is directed to a mirror 20 and from there it is reflected to a concave reflector 19 whose position can be varied by means of an adjusting means 18 and which is position sampling means 2
8, the sampling means detect the position of the concave reflector 19 relative to the radiation source. A carrier gas container 3 is connected to the radiation source 21 via a conduit 24.
0 is connected. A valve 29 is inserted into this conduit 24 and is actuated by a regulating means 31, which may be, for example, a magnetic regulating valve or a stepping motor. An atomizer 33 is inserted into the conduit 24 following the valve 29 . This one is equipped with a sample injection tube 33'. Microprocessor 32 is connected to servo motor 10 via line 101 and signal detector 1 via line 16'.
6, a pick-up device 27 via a line 27'', adjustment means 18 and 31, a power conditioning device 26 via a line 26'', and a position sampling means 28, respectively. The detector 1G detects the position of the inset 9 and, in particular, the position of the eight inset holes 11 relative to each photodetector 6 by scanning the coded marks 15. The resulting signals are fed via line 16' into the microprocessor 32, in which each measurement index value, namely observation height, power consumption and carrier gas flow rate, is sent to the inset unit 9 for the detector 6.
is stored for each relative position.

The optical cable 4 to transmit each spectral line for which the same or similar measurement index value is required is inserted into a respective fitting hole 11, which fitting hole is connected to each detector 6.
are optically coupled.

After having previously ascertained the actual values for the position of the concave reflector 19 and the actual values for the power produced by the high-frequency generator 25, resulting in an indication of the observation height, the microprocessor 32 determines its telescoping unit 9. power control device to adjust each measurement index value according to the set position of
31 and the drive device 18, respectively. Furthermore, the drive means 31 for actuating the valve 29 receives a signal whereby the necessary carrier gas is supplied to the conduit 2.
4 to carry the sample material to be analyzed to the radiation source. The device according to the invention is not limited only to specific optical means for optical dispersion.

For example, Czerny-Turner.

Constructions according to E bert-Fast and Rowland, as well as various Nigel systems, can be used. Furthermore, the present invention is not limited only to radiation spectrometry; it can equally be used in multichannel atomic absorption analysis or spectrophotometry.

In operation, the sample material to be analyzed is inserted through the sample injection tube 33- into the atomizer 33, where it is atomized and exposed to the radiation Il through the conduit 24.
l 21 is carried inside. The position index value (observation height) of the sample material vapor of this radiation source is regulated by the pressure of the carrier gas from the storage vessel 30, which pressure is controlled by the valve 29.
regulated by a drive 31 for. radiation source 2
1, each IC element contained in the sample material is excited at a different position of the radiation source and emits radiation 17. For example, elements such as Na, Li, Pb, etc. are excited in the first position, lee, Ni, Cr, Go are excited more centrally within the radiation source, and PSAS, C, etc. are excited in the third position. be done.

The emitted radiation 11 is directed by a reflector 20 onto a concave reflector 19, which is adjusted to the corresponding position, and in this example to the position of Fe1Ni, Cr, co.

The respective adjustment values are stored in the microprocessor 32 and, by manual input (not shown), the operator sets the reflector 19 via means 18 and 28 to a pair of central positions. The reflector 19 directs the radiation 17 towards the optical dispersion means 1, where corresponding spectral lines are formed depending on each element contained in the sample. The mask 2 is provided with correspondingly arranged respective slits, which face the light entrance surface 4' of the optical cable 4, which is fastened to the base 3 in its mounting.

According to the program of the analysis, the operator selects each optical cable 4 such that it is in each case associated with a corresponding spectral line of an element and, in the simplest case, of the element labeled by a tracer (not shown). When FCs are to be detected among other various elements, their light exit surface 4'' is inserted into the 8 fitting hole 11, i.e. in the corresponding section 8 of its fitting unit 9 the ``e'' For the first line, fit into the hole A, a,
and inserted into the fitting hole [3, a for the second line of [e].

Of course, it is also possible to insert another set of optical cables 4 into other fitting holes 11 in order to detect other elements. For example, a servo motor can be
10 and engage according to a command signal from the microprocessor 32 via line 101;
Unit 9 has each slit 12 in columns a and [
Detection unit 1 is at this position.
5.16, and if this position is reached, the detector unit 15 sends a corresponding signal via line 16' to the microprocessor 32, which issues a stop signal to the servo motor 10. .

The optical cables 4 inserted in rows a and f transmit the spectral lines, if any, from the optical dispersion means 1 to the detector 6, in the case of the Fe2
In addition to the two spectral lines, five additional elements can be detected. In the same way, the next row b19 to rows e, j, respectively, are scanned by a respective detector 6, which is coupled to the electronic evaluation device 13.

Therefore, the first section 8 (A, B, a, b
, c, d, e) receives the light from each of the optical cables 4 for Fe and converts the light into respective electrical signals. These signals are evaluated by 3 in an electronic device and stored by respective means (not shown) or fed into an output converter for example for output to a visual device (not shown). .

In a preferred embodiment, 140 optical cables 4 are included, each end of which is fixed in a mounting 3, and fitting units 1-9 evaluate, for example, 60 spectral lines. is designed to.

The pr value index (i.e. the observation height and the position of excitation of a particular element in the radiation source) and the key ↑7 gas pressure and power consumption m can be adjusted at any suitable point in the analytical operation and the micro It can be controlled by a corresponding program stored in processor 32.

A detailed explanation of each factor for operation and their interrelationships will be omitted here, but they can be explained, for example, by ICPInforIllationNew
s Letter, Vol. 8, No. 062, pp. 88 et seq. (July 1982).

Furthermore, the drawing in appendix (=I) shows a spectrometer according to the invention in a highly schematic diagram, so that, for example, the optical dispersion means 1 may be of any other suitable type. The spacing between the dispersion means and the mask 2 is in any case a matter of choice.Servo motor
10 can also be replaced with a step motor.

In this case the detector 16 can be omitted, since in that case the step rate is determined by the microprocessor 3.
This is because it is stored in 2. However, a zero point indicator is required.

[Brief explanation of the drawing]

The attached figure is a schematic illustration of a multi-element analyzer according to the present invention. 1... Optical dispersion means 2.7... Mask 4... Optical cable 5... Detector unit 6... Detector 8.14... Section 9... Fitting unit 10... Servo motor 11... Fitting hole 13...
...Electronic evaluation device 15...Position indicator 16...Position detector 17...Radiation flux 18.31
... Adjustment means 19 ... Concave reflecting mirror 20 ... Deflection reflecting mirror 21 ... Radiation source 22 ... Discharge tube 23.
... Coil 24 ... Conduit 25 ... High frequency generator 16', 26
', 26'', 27', 27'', 101... line 26...
- Power control device 27...Measurement value pickup device 28...Position sampling means 29...Valve 30...Carrier A7 gas container 32...Microprocessor 33...Atomizer 33-...Sample injection Administrative Patent Applicant Bev Nord J. Le Zeis Jena Patent Attorney Patent Attorney Matsu 1) Ministry Amendment of Error Procedures (Voluntary) February 27, 1985 Commissioner of the Patent Office Relationship to the IL case Patent applicant name Bev Carl Zeiss Jena 6, subject of amendment Drawing hand vr:? ...Shoza (method) % formula % Multi-element analysis method and device name Name Bebb Carl Zeiss Jena 6, subject to correction Full text of the specification

Claims (1)

[Claims] (1) When simultaneously analyzing multiple elements using a spectrometer, a sample substance is excited to emit radiation, and a line spectrum or a band spectrum is formed from this radiation; A line or band spectrum is transmitted to a photodetector by an optical cable, and in this case, the spectral lines or bands for which at least approximate excitation condition index values are required are grouped into several groups, and these groups are sequentially divided into each of the above-mentioned groups. An analysis method comprising subordinating a photodetector to a photodetector. (2) In a spectrometer device for simultaneously analyzing a plurality of elements, an excitation source for exciting a sample to emit radiation, and a reflecting mirror means. and an optical dispersion means, provided that the mirror means is for directing the radiation onto the optical dispersion means, and the optical dispersion means is dependent on the sample to be analyzed. to produce a plurality of spectral lines in the first plane (1) and including as many exit slits as the required number of spectra present; a first mask lying in a plane; a plurality of optical cables each having a light entrance surface and a light exit surface (with the proviso that the first plane and the second plane substantially coincide); and the optical cables. means for mounting each of the light entrance surfaces of in a third plane, with the proviso that the third plane is parallel to and closely spaced following the second plane, and said light entrance surface is optically coupled to a corresponding one of said spectral lines (if any) via any of said slits; a fitting unit with a fitting hole, (provided that the fitting unit 1- is divided into a plurality of sections of substantially the same size) and the fitting unit 1- is divided into a plurality of sections of substantially the same size; (1) each of said inset holes in said inset unit is arranged substantially in a number of rows and columns arranged at right angles to each other; The mask includes a number of slits equal to the number of sections present in the inset unit, these slits being arranged parallel to the rows of the inset holes and perpendicular to the rows, and each a photodetector array consisting of a number of photodetectors equal to the number of sections present in the inset unit (slits are combined with corresponding sections of the inset unit); The light exit of the optical cable is arranged in a parallel plane following the mask at a narrow distance, and one light exit side of the optical cable is connected to each light detector of the photodetector array through the fitting unit and the second mask. displacement means for displacing the fitting unit (optically coupled to the container) in a fourth plane defined by each row and each column in a direction perpendicular to each column; , a detection means for specifying the relative position of a row of said fitting holes with respect to each photodetector (provided that this detection means is provided at an end of said fitting unit adjacent to each row of the upper row); a microprocessor; a first coupling means for coupling the displacement means to the microprocessor; a second coupling means for coupling the detection means to the microprocessor; and an output section of each light detection means. an evaluation unit coupled thereto, provided that this evaluation unit is used to evaluate the output signal of each photodetector which, if present, is indicative of the chemical substance contained in said sample material; ) and excitation condition indicator value adjustment means operatively coupled to said excitation source and said microprocessor, wherein said microprocessor adjusts at least one excitation condition indicator value based on information from said detection means. Set up a corresponding column of each inset hole for those photodetectors in the spectrometer device above. (3) The excitation condition index value adjusting means includes a power control device for controlling the power supplied from the power source to the excitation source heating means, and a power control device for controlling the reflecting mirror means to excite each sample substance in the excitation source. 3. The apparatus of claim 2, comprising adjustment means for relative adjustment to the position of the excitation source and a control device for controlling the flow of carrier gas from the carrier gas source to the excitation source. (4) The apparatus according to claim 3, wherein a sample injection tube is provided between the control device and the excitation source for supplying sample material to the excitation source. (5) The device according to claim 4, wherein each section of the fitting unit is provided with at least one row of fitting holes. (6) each optical cable serves to detect a specific spectral line when inserted into a specific fitting hole;
An apparatus according to claim 5. (7) at least one or more adjustable index values, i.e. the position of the excitation in said excitation source, the amount of power input supplied from the power supply to the heating means, the flow meter of the carrier gas, etc., in combination with a specific spectral line consisting of and thus combined with the insertion of an optical cable into the corresponding fitting hole of said fitting unit, and this combined state is stored in said microprocessor and said detecting means is configured to detect a particular spectral line consisting of When the combined corresponding signals are sent to the corresponding photodetectors by the corresponding optical cables, the microprocessor sends corresponding setting signals to the regulating means, the power distribution control device, and the control device, respectively. 8) Insertion of the same section of the optical cable into the recessed hole in the same row increases the light intensity of each different spectral line from the element. The role of
An apparatus according to claim 2.