JPS63186116A - Storage device for data input of spectral analyzer - Google Patents

Abstract

PURPOSE:To secure the fast response of A/D conversion and to reduce the storage capacity of a data memory to half by utilizing a level position pulse from spectral analyzer as a reference trigger for the start of the A/D conversion of an intensity signal. CONSTITUTION:The level position pulse as the standard of the level of mass, wavelength, etc., outputted by the spectrum analyzer 1 are inputted 2 as the trigger pulse for the start of the A/D conversion. The intensity signal from the analyzer 1 is A/D-converted 6 in response to the trigger pulse. Therefore, a CPU need not be interposed at the time of the A/D conversion 6 and the fast response of the A/D conversion can be secured. Then the intensity signal data after the A/D conversion 6 is stored in the intensity signal data memory 10. At this time, a write address counter counts level position pulse utilized as the trigger for the start of the A/D conversion and its counted value is supplied to the memory 10 as write address specification data, so only the intensity signal data is stored and made to correspond to a mass number, thereby reducing the storage capacity of the data memory to half.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a data storage device that inputs and stores data obtained by a spectrum analysis instrument such as an X-ray analyzer or a mass spectrometer.

(b) Prior art and its problems In general, spectrum analysis equipment, such as a mass spectrometer, performs mass scanning and measures its intensity signal, and analyzes mass spectra with the horizontal axis as the mass number and the vertical axis as the signal intensity. Perform qualitative and quantitative analysis, etc. In this case, in order to perform various data processing, it is necessary to temporarily store the output data from the spectrum analyzer in memory.
The data input storage device shown in the figure is used.

When this data storage device is connected to a mass spectrometer,
The mass spectrometer a outputs an ion intensity signal obtained during mass scanning and a corresponding mass number pulse serving as a measure of the mass level. Therefore, after A/D converting the above ion intensity signal using an A/D converter, it is imported into the CPUc, and the current ion intensity signal data is successively compared with the previous one, and based on the comparison results, the ion intensity signal is changed. Find the curve point and detect the peak top. In addition, the mass number pulse output from the mass spectrometer a is counted by the mass number counter d, and when the peak top is detected as described above, the CPU c converts the count value at that point into the mass number data (m/ z). And CPUc
The ion intensity signal data and mass number data are stored in dedicated data memories 6 and f, respectively.

In this way, conventionally, the CPU itself judges the presence or absence of a peak top solely based on the value of the ion intensity signal data after A/D conversion.
The CPU is always involved in setting the D conversion start timing.
In addition, a program for determining the peak top is required. Therefore, a time lag occurs between the start timing of A/D conversion and the detection of the peak top.
/D conversion lacks responsiveness when high speed is required;
As a result, the presence of the peak top may be overlooked. Therefore, when this data storage device is used in a mass spectrometer, there are drawbacks such as the inability to accurately measure the exact mass number.

Furthermore, in the past, ion intensity signal data and mass number data were stored separately in a data memory, which resulted in inconveniences such as the need for a large memory capacity for the entire apparatus.

The present invention has been made in view of the above circumstances, and aims to reduce the storage capacity of the data memory by half compared to the conventional one while ensuring high-speed response of A/D conversion. purpose.

(C) Means for Solving the Problems In order to achieve the above object, the present invention scans energy levels such as mass and wavelength, and measures the intensity signals obtained accordingly. In a data input storage device used in a spectrum analysis device that outputs a level position pulse that serves as a guide for the level of the detected intensity signal and the corresponding mass, wavelength, etc., the level position pulse is used as a trigger for starting A/D conversion. An A/D converter that inputs the intensity signal as a pulse and A/D converts the intensity signal in response to the A/D converter, an intensity signal data memory that stores the intensity signal data after A/D conversion, and counts the level position pulse. and a write address counter that provides the count value to the data memory as write address designation data.

(D) Effect In the data input storage device of the present invention, a level position pulse that is a guide for the level of mass, wavelength, etc. output from a spectrum analyzer is input as a trigger pulse for starting A/D conversion. In response, the intensity signal from the analytical instrument is A/D converted. Therefore, the intervention of the CPU is not required during A/D conversion, and high-speed responsiveness of A/D conversion can be ensured.The intensity signal data after A/D conversion is stored in the intensity signal data memory. At that time, the write address counter counts the level position pulse used as a trigger to start A/D conversion, and provides the count value to the intensity signal data memory as write address designation data, so only the intensity signal data is stored. However, this can be correlated to its mass number. Therefore, the storage capacity of the data memory can be halved compared to the conventional one.

(E) Embodiment FIG. 1 is a block diagram when the data storage device of the present invention is used in a mass spectrometer. In the figure, the symbol l
is a mass spectrometer as a spectrum analysis device, and from this mass spectrometer 1, along with mass scanning, an ion intensity signal and a level position pulse (in this example, a mass number pulse) that is a guide for the corresponding mass level are transmitted from the mass spectrometer 1. ) is output. This mass number pulse is applied to the ion mass number (m/
z) is output in units of t, 'to o.

2 is a data input storage device that inputs and stores the output signal from the mass spectrometer 1; 4 is a frequency divider that divides the mass number pulse from mass spectrometer 1 into l/10, and 6 is the mass number pulse output from mass spectrometer 1 or the mass after being divided by frequency divider 4. Several pulses are input as trigger pulses to start A/D conversion, and in response, the ion intensity signal is converted to A/D conversion.
This is an A/D converter that performs /D conversion.

8 is a maximum value extraction circuit for extracting ion intensity signal data indicating the maximum value from several A/D converted ion intensity signal data obtained by mass scanning in a predetermined range;
12 is an intensity signal data memory that stores the ion intensity signal data that has passed through the maximum value extraction circuit 8; 14 is an A/D;
This is a write permission signal generator that outputs a write permission signal to the intensity signal data memory 10 in response to an A/D conversion end signal outputted from the converter 6 every time the A/D conversion ends.

16 is the ion mass number (m/z) l/ from the mass spectrometer I.
In the case of so-called milli-mass measurement, in which the ion intensity signal is A/D converted and captured every time a mass number pulse is output every 100 units, and in the case of so-called milli-mass measurement, the ion intensity signal is obtained every time the mass number pulse is divided by I/10. This is a measurement mode selection switch that is operated according to each mode, including so-called integer mass measurement in which data is A/D converted and taken in. Further, 18 is a latch circuit that latches the output of the measurement mode selection switch I6, 20 is an RS flip-flop that is repeatedly set and reset according to the operation of the measurement mode selection switch I6, and 22 is an RS flip-flop whose input terminal is connected to the RS flip-flop 20. A first AND gate 24 has one input terminal connected to the output section of the mass number pulse of the mass spectrometer 1, and the other input terminal is a frequency divider. The second AND gates 4 and 26 are respectively connected to the CPU.

Next, regarding the operation of the data input storage device l of the present invention,
This will be explained with reference to FIG.

(i) In the case of millimas measurement In this measurement mode, it is necessary to accurately determine the ion mass number at the peak top position within a limited mass scanning range. Therefore, first, operate the measurement mode selection switch 16 and use the output of the latch circuit I.
8 to set the RS flip-flop 20. This releases the first AND gate 22. Also,
The CPU 26 recognizes the millimeter measurement mode from the output signal of the measurement mode selection switch 16.

When analysis is started next in this state, an ion intensity signal and a mass number pulse are output from the mass spectrometer 1 in conjunction with mass scanning. This mass number pulse is passed through the first AND gate 22 to the A/D converter 6 and the write address counter 12. be given to each. The A/D converter 6 inputs this as a trigger pulse to start A/D conversion every time a mass number pulse is output every 1/100 unit of the ion mass number (m/z), and responds to it. The ion intensity signal is A/D converted. Therefore, since the CPU 26 is not involved in setting the timing for starting A/D conversion, high-speed responsiveness of A/D conversion is ensured. The A/D-converted ion intensity signal data is sent to the next maximum value extraction circuit 8, but in the case of millimeter measurement, the operation of the circuit 8 is stopped by a control signal from the CPU 26. Therefore, the A/D converted data passes through this circuit 8 as it is and is applied to the intensity signal data memory 10. Further, when the A/D conversion is completed, the A/D converter 6 sends the A/D
A conversion end signal is output and a write permission signal is generated 9i
14 outputs a write permission signal to the intensity signal data memory 10 in response to this signal.

On the other hand, a write address counter (2) counts each time a mass number pulse is given from the first AND gate 22, and stores the count value in the intensity signal data memory 1.
0 as address data for specifying writing of ion intensity signal data. Thereby, the intensity signal data is stored at the address corresponding to the mass number value.

In this way, the above operations are repeated until ion intensity signal data over a predetermined mass scanning range is obtained.

(ii) Integer mass measurement In this measurement mode, the precision required for determining the mass number as in millimeter measurement is not required, but the position of the peak top is detected in a wide mass scanning range and the spectral distribution is measured. This is necessary.

Therefore, in this case, the measurement mode selection switch I6 is operated, and the RS flip-flop 20 is reset via the latch circuit 18 with its output. This releases the second AND gate 24.

Further, the CPU 26 recognizes the integer mass measurement mode from the output signal of the measurement mode selection switch 16.

When analysis is started next in this state, an ion intensity signal and a mass number pulse are output from the mass spectrometer 1 in conjunction with mass scanning. A mass number pulse is output from the mass spectrometer 1 in units of 1/100 of the ion mass number (m/z), and this pulse is divided into 1/10 by the frequency divider 4. and,
This frequency-divided mass number pulse is input to the CPU 26, and is also given to the A/D converter 6 and write address counter 12 via the second AND gate 24, respectively. The A/D converter 6 converts each frequency-divided mass number pulse into A
It is input as a trigger pulse to start /D conversion, and the ion intensity signal is A/D converted every time this pulse is input.

The A/D converted ion intensity signal data is sent to the maximum value extraction circuit 8 at the next stage.

In the case of integer mass measurement, as shown in FIG. 2, the CPU 26 calculates the values of the mass number pulses pi, pisu1, . Each mass number pulse pi, pis1, which becomes an integer value by determining
Maximum value extraction circuit 8 only within a certain range R before and after including ...
make it work. Therefore, only ion intensity signal data included within the certain range R is sampled. Next, the maximum value extraction circuit 8 extracts ion intensity signal data indicating the maximum value from among the sampled ion intensity signal data. As a result, the peak top included within the certain range R is detected, and the ion intensity signal data of the peak top is given to the intensity signal data memory 10. The detection of the peak top is performed between the sampling timing that includes the current integer-valued mass number pulse pi and the sampling timing that includes the next integer-valued mass number pulse pisu1, so the timing of the start of A/D conversion is It has no effect on the

On the other hand, the write address counter 12 counts each time the frequency-divided mass number pulse is applied from the second AND gate 22. Thereby, the intensity signal data is stored at the address corresponding to the ion mass number.

In this way, the above operations are repeated until the peak top position is detected in the desired mass scanning range and spectral distribution data is obtained.

Although this example describes the case where it is used in a mass spectrometer, it is not limited to this, and can also be used in various analytical instruments that measure spectral data such as an X-ray analyzer and an emission analyzer. Of course, the present invention can be applied.

(F) Effects As described above, according to the present invention, the level position pulse, which is a guide for the level of mass, wavelength, etc. output from the spectrum analysis device, is used as the reference trigger for starting A/D conversion of the intensity signal. , CPU intervention is not required during A/D conversion, and high-speed responsiveness of A/D conversion can be ensured. Therefore, when used in a mass spectrometer, it is possible to obtain ion intensity signal data corresponding to an accurate mass number.

Moreover, since the count value obtained by counting these level position pulses is made to correspond to the write address of the intensity signal data memory, excellent effects such as being able to reduce the storage capacity of the data memory by half compared to the conventional method are exhibited. be done.

[Brief explanation of the drawing]

Fig. 1 is a block diagram when the data input storage device of the present invention is used in a mass spectrometer, and Fig. 2 shows the ion intensity signal obtained during mass scanning and the corresponding mass level. FIG. 3, which is an explanatory diagram of a characteristic spectrum showing the relationship between position pulses, is a block diagram when a conventional data input storage device is used in a mass spectrometer. 1... Mass spectrometer, 2... Data input storage device, 6
. . . A/D converter, 10 . . . Intensity signal data memory, 12 . . . Write address counter.

Claims (1)

[Claims] (1) While scanning energy levels such as mass and wavelength,
A data input storage device used in a spectrum analysis device that measures the intensity signal obtained along with this and outputs a level position pulse that is a guide to the level of the obtained intensity signal and the corresponding mass, wavelength, etc. an A/D converter that inputs the level position pulse as a trigger pulse for starting A/D conversion and converts the intensity signal from A/D in response to the A/D converter; and an A/D converter that converts the intensity signal into A/D; A spectrum analysis device comprising: an intensity signal data memory that stores data; and a write address counter that counts the level position pulses and provides the count value as write address designation data to the data memory. Data entry storage device.