JP2006162259A - Spectrometry system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectrometry system which does not require measurers to separately measure a background spectrum and a sample spectrum. <P>SOLUTION: The spectrometry system is provided with both a light emergent means for guiding light to a sample mounting position and a photo-detection means for detecting light emergent from a sample and measures a sample spectrum by irradiating the sample with light and detecting emergent light from the sample. The spectrometry system is provided with a detection means arranged in the vicinity of the sample mounting position for detecting information as to whether the sample is mounted or not; a determination means 24 for determining whether the sample is mounted to the sample mounting position or not on the basis of a signal from the detection means; a control means for controlling the light emergent means and the photo-detection means according to preset measurement conditions when it is determined by the determination means that the sample is not mounted to the measuring position and automatically acquiring background data by performing measurement without the sample mounted; and a storage means for storing acquired background data. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a spectroscopic measurement apparatus, and more particularly to an improvement of a background spectrum acquisition mechanism.

In a spectroscopic measurement apparatus that employs an optical system with a single optical path, for example, when calculating an absorption spectrum of a sample, it is necessary to separately measure a spectrum of transmitted light from the sample and a background spectrum (for example, Patent Documents). 1). In other words, the background spectrum is measured without the sample being placed, then the spectrum of the transmitted light from the sample is measured, and the absorption spectrum of the sample is obtained by comparing the spectrum of the transmitted light with the background spectrum. It is done.
JP 2000-74826 A

Usually, the spectrum measurement with the sample installed and the background spectrum measurement must be performed with the same parameter settings, so the time spent for the background measurement is almost the same as the time required for the sample spectrum measurement. Be the same. Therefore, the total measurement time requires twice as long as the time required for measuring the spectrum of the sample.
Moreover, in order to suppress the influence which the fluctuation | variation of the atmosphere on an optical path has on a measurement, it is so preferable that the time difference of the measurement of a sample spectrum and a background spectrum is short.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a spectrometer that does not require the measurer to separately measure the background spectrum and the sample spectrum even in an optical system with a single optical path. is there.

In order to achieve the above object, a spectroscopic measurement apparatus of the present invention comprises a light emitting means for guiding light to a sample installation location and a light detecting means for detecting light emitted from the sample, and the light is applied to the sample. In a spectroscopic measurement apparatus that measures a sample spectrum by irradiating and detecting light emitted from the sample, a detection unit that is disposed in the vicinity of the sample installation location and detects information about the sample installation state, and a signal from the detection unit On the basis of the determination means for determining whether or not the sample is installed at the sample installation location, and when the determination means determines that the sample is not installed at the measurement position, according to the measurement conditions set in advance, By controlling the light emitting means and the light detecting means and performing measurement in a state where the sample is not installed, the control means for automatically acquiring the background data, and the acquired background data And wherein further comprising the 憶 storing means.
In the spectroscopic measurement apparatus, the storage unit may store background data for a predetermined number of times, and replace the background data acquired at the oldest time with the background data acquired at the newest time. Is preferred.
In the spectroscopic measurement apparatus, in place of the determination unit and the control unit, a spectrum shape confirmation unit for determining whether or not the sample is installed based on the measured spectrum data is provided, and the sample is installed by the spectrum shape confirmation unit. It is preferable to store the spectrum data in the storage means as background data when it is confirmed that the data is not present.

According to the spectroscopic measurement apparatus of the present invention, it is possible to determine whether or not a sample is installed at the sample installation location and automatically perform background measurement. It is not necessary to perform the measurement separately, and the measurement time taken by the measurer can be shortened.
In addition, according to the spectroscopic measurement apparatus of the present invention, the background data for a predetermined number of times is stored, the background data acquired at the oldest time is replaced with the background data acquired at the newest time, and stored. Therefore, the measurer can always use the latest background data.

Preferred embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a spectrometer according to the present embodiment. In this embodiment, a Fourier transform infrared spectrophotometer (FTIR) is described as an example, but the present invention is not limited to this.
1 includes an FTIR main body 12 and a computer 14 that controls the FTIR main body 12, processes measurement data, and the like. The FTIR main body 12 according to this embodiment includes a sample chamber 16 in which a sample is placed, a light emitting means 18 for introducing light into the sample chamber 16, and a light detecting means 20 for detecting light emitted from the sample chamber. Is done. Further, detection means 22 for detecting information related to the sample installation state is provided in the vicinity of the sample installation location such as the sample chamber 16 of the FTIR main body 12.

The computer 14 controls the judgment means 24 for judging whether or not the sample is installed at the installation location in the sample chamber 16, and the light emitting means 18 and the light detection means 20 of the FTIR main body 12 based on a signal from the detection means 22. And a control means 26 for performing the above. When the determination means 24 confirms that no sample is installed, the control means 26 automatically performs background measurement.
The light emitting means 18 includes a light source 32 and an interferometer 34, and generates interference light by passing light emitted from the light source 32 through the interferometer 34. In the present embodiment, an example in which the interferometer is arranged in the front stage of the sample chamber is shown. However, the configuration is not limited thereto, that is, the interferometer is provided in the front stage of the detector as a light detection means. It is good also as a structure.

The detection signal from the light detection means 20 is converted into a digital signal, sent to the computer 14, and stored in the storage means 28. Further, these detection signals are processed by the calculation means 30 in the computer 14. In FTIR, spectrum data is obtained by Fourier transforming the interferogram data acquired by the light detection means 20.
The detection means 22 is composed of a sensor attached to a sample chamber lid, a sample holder serving as a sample installation location, and the like. For example, as shown in FIG. 2, the detection means 22 is attached to an open / close state detection unit 36 that detects the open / close state of the sample chamber lid of the sample chamber 16, a sample holder that holds a sample cell, and the like. And an installation state detection unit 38 for detecting presence or absence. As a sensor used for the open / close state detection unit 36 and the installation state detection unit 38, a micro switch, a photo interrupter, a hall sensor, or the like may be used.
The determination means 24 constantly monitors the signal sent from the detection means 22 and determines whether or not a sample is installed based on the information.

When the determination unit 24 confirms that no sample is installed, the control unit 26 performs background measurement according to various measurement parameters set in advance. The measurement parameters are stored in the storage unit 28, and the control unit 26 reads out the measurement conditions and performs measurement based on the measurement conditions.
Further, data obtained by background measurement (data of one integration number) is stored in the background data storage unit of the storage means 28 for a preset number of times (at least for the number of integrations in sample spectrum measurement). These data are stored so that the measured time series can be understood by a method such as storing the data in association with the measured time. When more background measurement data is obtained than the set number of times, the oldest data is deleted and replaced with the latest data.
The above is the schematic configuration of the present embodiment, and the operation thereof will be described below.

  First, the determination means 24 constantly monitors signals from the detection means 22 and automatically determines whether or not a sample is installed based on those signals. For example, as shown in FIG. 2, the installation state detection unit 38 provided in the vicinity of the sample installation location detects whether or not a sample cell or the like is installed at the installation location such as the sample holder and determines the information. Send to. The open / close state detection unit 36 provided in the vicinity of the sample chamber cover detects the open / close state of the cover and sends the information to the determination means 24. Then, when the signal from the installation state detection unit 38 is that when the sample is not installed, the determination unit 24 further confirms that the lid of the sample chamber is closed by the signal from the open / close state detection unit 36, A signal is sent to the control means 26 to obtain background data. As described above, the determination unit 24 confirms that the sample chamber lid is closed in addition to the presence or absence of the sample. That is, the background data is prevented from being measured in an inappropriate state, for example, a state in which external disturbance light enters the sample chamber 16 and a state in which the atmosphere in the sample chamber 16 fluctuates.

The control unit 26 operates the light emitting unit 18 and / or the detection unit 20 based on the measurement conditions stored in the storage unit 28. The light emitted from the light emitting means 18 is introduced into the sample chamber 16 and further emitted from the sample chamber 16 toward the light detecting means 20. The detection signal detected by the light detection means 20 is subjected to processing such as AD conversion, and then sent to the computer 14 for data processing.
The background spectrum thus obtained is stored in the storage means 26. The above background measurement is repeated until the measurer installs the sample, and a plurality of background data are stored. Since at least the same number of background data as the number of times of integration at the time of sample spectrum measurement is required, the background data is stored at least for the number of times of integration. When data is obtained more than a predetermined number of times, the oldest data is replaced with the newest data. At the time of sample spectrum measurement, background data corresponding to the number of times of sample spectrum integration is integrated and used.

As described above, according to the spectroscopic measurement apparatus of the present embodiment, the apparatus automatically acquires the latest background data, so that the measurer does not need to measure the background spectrum separately. That is, the measurement time is greatly shortened because the background measurement is performed using the time when the measurer is not using the apparatus.
In addition, since the latest background data immediately before the sample is installed can be used, the influence of the atmosphere in the optical path and the stability of the apparatus can be minimized.

Moreover, in general, in a spectroscopic measurement apparatus such as FTIR, the constituent members between the interferometer and the detector are unitized and analyzed so that various measurement methods can be easily selected according to the form of the sample and the purpose of measurement. It is an accessory that can be attached to and detached from the sample chamber of the main body. By selecting such accessories according to the sample form and measurement purpose and providing them in the main body of the analyzer, it is possible to easily cope with various measurement methods. These measurement methods include reflection ATR measurement, high-sensitivity reflection measurement, diffuse reflection measurement, infrared microscopic measurement, and the like.
In a spectroscopic measurement apparatus in which various accessories can be detachably provided in the apparatus main body, an accessory recognition function is provided. For example, a recognition tag having a memory or the like that stores accessory information is provided on the accessory, and a reading means for reading the information stored in the recognition tag is provided at the installation location of the accessory so that the accessory can be connected to the computer. Configured to send information.
Therefore, in the above embodiment, based on the identification signal from the sensor provided in the accessory, the background data is stored in the storage means for each type of accessory, or the background data is associated with the type of accessory. It is preferable to memorize.

In the embodiment of FIG. 1, the presence or absence of the sample is determined based on the signal from the detection unit installed in the sample chamber or the like. However, the spectrum data is actually measured, and the sample data is measured based on the spectrum data. It is also possible to determine the presence or absence of installation. FIG. 3 is a schematic diagram showing the configuration. Components corresponding to those in FIG. 1 are denoted by reference numeral 100 and detailed description thereof is omitted.
In the embodiment of FIG. 3, a spectrum shape confirmation unit 142 that determines whether or not a sample is installed based on the acquired spectrum data is provided. The interferogram acquired by the light detection means 120 is sent to the computer 114, where it is Fourier transformed by the Fourier transform means 140 to obtain spectral data. This spectrum data is sent to the spectrum shape confirmation means 142, where it is determined whether the data is when the sample is set or when the sample is not set based on the shape information of the spectrum data. When the spectrum shape confirmation unit 142 confirms that no sample is installed, the spectrum data is stored in the background data storage unit 144 of the storage unit 128 as background data. When the spectrum shape confirmation unit 142 determines that the sample is installed, the spectrum data is stored in the spectrum data storage unit 146 of the storage unit 128.

As a method of determining the presence / absence of a sample from spectrum shape information, the presence / absence of a sample may be simply determined based on the presence / absence of a peak of calculated spectrum data. For example, as shown in FIG. 4 (the figure (a) is the spectrum when the sample is not installed, and the figure (b) is the spectrum when the sample is installed), the predetermined threshold (dotted line in FIG. 4) is set and acquired. The presence or absence of the sample is determined based on whether or not the intensity of the measured spectrum exceeds a threshold value. Although FIG. 4 shows an example in which the threshold is set over the entire wave number range of the acquired spectrum, the threshold may be compared only with a predetermined wavelength range. This threshold value can be appropriately set by those skilled in the art based on background data acquired in the past. Furthermore, in addition to the spectrum intensity, the area of the spectrum and the local dispersion value in a certain interval (the wave number region is divided by a predetermined interval, and the dispersion value is calculated within that interval; see FIG. 4C). On the other hand, a predetermined threshold value may be set, and if the threshold value is exceeded, it may be determined that the sample is installed. Further, the area of the difference from the background spectrum data stored in advance can be used as the judgment data.
When the accessory 148 is installed in the apparatus main body, the type of the accessory 148 is determined from the identification signal from the accessory 148, and the spectrum shape is determined corresponding to the accessory 148. That is, parameters for judging the installation status of the sample, for example, threshold values of spectrum intensity and area, background data stored in advance, and the like are read from the storage unit 128 according to the type of the accessory 148, and stored in them. Make a judgment based on this.

As described above, according to the present embodiment, it is possible to save the measurer's time for acquiring the background spectrum and to shorten the measurement time.
In the above embodiment, the Fourier transform infrared spectrophotometer has been described as an example. However, the present invention is not limited to this and can be applied to other types of spectroscopic measurement apparatuses.

1 is a schematic configuration diagram of a spectrometer according to an embodiment of the present invention. An example of the configuration of the detection means of this embodiment Schematic configuration diagram of a spectrometer according to a second embodiment of the present invention Explanatory drawing of the spectrum data confirmation method in the apparatus of embodiment of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Spectrometer 12 FTIR main body 14 Computer 16 Sample chamber 18 Light emitting means 20 Light detecting means 22 Detection means 24 Judging means 26 Control means 28 Storage means 30 Calculation means

Claims (3)

A light emission means for guiding light to a sample installation location; and a light detection means for detecting light emitted from the sample; the sample spectrum is obtained by irradiating the sample with light and detecting light emitted from the sample; In a spectrometer for measuring
A detecting means arranged in the vicinity of the sample installation location for detecting information relating to the sample installation state;
A judging means for judging whether or not a sample is installed at a sample installation location based on a signal from the detection means;
When the determination means determines that the sample is not installed at the measurement position, the light emission means and the light detection means are controlled according to the measurement conditions set in advance to perform measurement in a state where the sample is not installed. Control means for automatically acquiring background data;
A spectroscopic measurement device comprising storage means for storing the acquired background data. The spectroscopic measurement device according to claim 1,
The storage means stores background data for a predetermined number of times, and stores the background data acquired at the oldest time by replacing it with the background data acquired at the newest time. The spectroscopic measurement device according to claim 1,
In place of the determination means and the control means, provided with a spectrum shape confirmation means for judging whether or not a sample is installed based on the measured spectrum data, and the spectrum shape confirmation means confirms that the sample is not installed And storing the spectrum data in a storage means as background data.

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