JPS6219946Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a multi-channel double beam dual wavelength spectrophotometer.

In the field of automatic biochemical analyzers, this dual-wavelength spectrophotometer can simultaneously analyze a large number of samples with different test items. A multi-channel dual-wavelength spectrophotometer has been developed that is highly energy efficient and capable of simultaneous analysis of multiple items using only an optical system including one or two Zerny-Turner spectrometers with few aberrations.
In this process, the transmitted light from a large number of sample cells arranged in the X-axis direction is passed through a single slit with a length in the X-axis direction, and the spectral bands of the transmitted light from each cell are dispersed in the Y-axis direction. In addition to projecting light onto a wavelength dispersion optical system arranged to obtain a spectrum, the light receiving part has a light receiving part for receiving the spectrum, and this light receiving part has a detecting part consisting of two or more detecting elements arranged in the Y-axis direction. The detection units are arranged in a plate shape in the X-axis direction corresponding to the appearance position of each spectral band. With the above configuration, this multi-channel dual-wavelength spectrophotometer can achieve extremely high resolution compared to filter-type devices, and can perform highly efficient measurements in the short wavelength region, where brightness is an issue with filter-type devices. Furthermore, it has the advantage that the wavelength can be selected only by the detection position.
However, the above device conventionally uses a single beam, and changes in the brightness of the light source directly affect the measured value. Therefore, a constant voltage device was used to stabilize the brightness of the light source, and moreover, a stabilization time of one hour or more was required after the power was turned on. However, automatic biochemical analyzers are often used for emergency tests in which samples brought in or collected must be analyzed immediately. Correspondingly, it is necessary to gradually reduce the voltage of the light source to about 80% of the rated voltage and put it on standby. Under these conditions of use of the light source lamp, the conventional single beam method cannot compensate for changes in brightness due to deterioration, even considering the lamp's lifespan.
This resulted in measurement errors and could not be put to practical use.
Furthermore, the energy of the light source with respect to the wavelength changes due to sudden changes in the outside temperature, etc., and the single beam method cannot compensate for energy fluctuations of the light source, that is, fluctuations in color temperature, especially at short wavelengths. Recently, the importance of clinical testing has increased, and 24
Currently, there is a strong demand for an apparatus that can maintain a constant brightness by compensating for energy fluctuations due to aging of the light source and other causes, and has high analysis precision.

This idea was made in view of the above-mentioned current situation, and it is an improvement on the multi-channel dual-wavelength spectrophotometer that has been developed in recent years, and completely eliminates energy fluctuations caused by deterioration of the light source due to continuous lighting for long periods of time and other factors. With regard to compensation, the conventional single-beam method is replaced with a double-beam method without making any major changes to the structure, and the brightness of the light source is automatically compensated to always remain constant, with the aim of improving analysis accuracy and extending the life of the light source lamp. It is something. In other words, a plurality of sample cells are arranged in a row in the X-axis direction, and the transmitted light from each of these sample cells is separated after passing through a single long slit in the X-axis direction. A wavelength dispersion optical system is arranged so that the spectral bands of light are respectively dispersed in the Y-axis direction, and at least two wavelength dispersion optical systems are arranged in the Y-axis direction in correspondence with each of the sample cells in one plane. A multi-channel double beam dual-wavelength system is provided with a spectral light-receiving section in which a detection section array consisting of detection elements is arranged in the X-axis direction in the same number as the number of sample cells corresponding to the appearance position of each spectral band. In the spectrophotometer, one standard sample cell is added and arranged in the row of sample cells, and one detection element is provided in the spectrum receiving section corresponding to the one standard sample cell. A multi-channel double, characterized in that it is additionally provided corresponding to the appearance position of the spectral band and is equipped with a circuit that automatically controls the light source brightness so as to keep the intensity of the specific spectrum of the light transmitted through the standard sample cell constant. This is related to a beam dual wavelength spectrophotometer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention will be explained below with reference to the drawings. Figure 1 is a configuration diagram of the optical system of the device seen from the front of the device, showing the luminous flux of this dispersive optical system on the meridian plane, and Figure 2 is a plan view seen from the top of the device, which also shows the sphere of the dispersive optical system. This shows the luminous flux on the defective surface. 1 is a light source with a diameter of about 1 mm and a length of about 10
It is a coiled tungsten filament of mm diameter, and its length direction is set as the X axis as shown in the figure.
2 is its lighting voltage automatic controller, 3 is a heat ray absorption filter, 4 is an aperture, 5 is a cylindrical lens,
Reference numeral 6 denotes a spherical lens, which is a condensing lens system that condenses light from a light source. 7 is a plane mirror, 8 is a spherical mirror, and this 8 is a flow cell 9a~ as shown in the figure.
Corresponding to each one of 9f and standard cell 10,
The number of cells is arranged in a line on the X axis. The flow cells 9a to 9f are arranged on the Y axis perpendicular to the X axis, for example, three on each side of the central standard cell 10.
A sample solution is injected into the standard cell 10, which is not a flow cell but is filled with air or water to form a pure solvent, and the intensity of light transmitted through this is used as a standard.
It may also be a cavity where no cells are placed. These 10 are one of the features of this device. Reference numeral 11 is an entrance slit long in the X-axis direction, 12 and 13 are spherical mirrors, 14 is a diffraction grating (dispersion element), and 15 is a light receiving section, in which semiconductor photodetecting elements described in FIG. 2 are arranged. An optical system having the same structure as the optical system described above is provided in this apparatus, although only 1' and 3' are shown and the whole is not shown, and the number of channels is increased. As shown in the figure, the light from the light source 1 passes through the flow cell 9 and the standard cell 10 three times, and
The image of light source 1 is shown in _Y in the longitudinal direction of the entrance slit _D
In this image, almost the boundary line of each cell is imaged. In this way, the focal plane of the 14 diffraction gratings corresponds to the spectral band of the transmitted light of each cell (dotted chain lines Ba to Bf in the figure) in the X-axis direction, and corresponds to the normal spectrometer in the Y-axis direction. Similar spectra (dotted and dashed lines Bu to Bl in the diagram correspond to each other. FIG. 2 shows the light receiving section (detector section) 15 of FIG. 1;
D, E, and F correspond one-to-one to each flow cell 9a to 9f, and the detection element 1 is located at the position where the spectral band appears.
6 are arranged, and dotted lines indicate detection elements 16 that are not selected. For example, 11 photodiodes are arranged between 340 nm and 700 nm. The S in the center is another feature of this device, and is similar to the standard cell 1.
0, and one photodiode for detecting a 600 nm spectrum is placed near the center.
The light flux with a wavelength of 600 nm that enters the detection element of this S is different from the light flux to other A to E, and this is the double beam method, and the light flux that enters the above S is transmitted through a cavity or a pure solvent such as water. It is light that shows a constant amount of light based on the light energy distribution unique to the light source lamp. Figure 3 shows an example of this.
The horizontal axis is the wavelength λ, and the vertical axis is the relative intensity e% of the light energy to it. For example, for this lamp,
The relative intensity e _s at 600 nm is 71%, and this e _s increases or decreases with changes in the temperature of the lamp filament, ie, the color temperature (it decreases as the color temperature decreases). The lighting voltage is automatically controlled by feeding back the change in the photocurrent of the photodiode S, which constantly monitors the _{e s} , to the light source voltage automatic controller 2 in the circuit 17 in FIG. Take action to keep it constant. This is the automatic light source brightness compensation device that is a feature of the device of this invention.
Next, the sample liquid transmitted light from each of the flow cells 9a to 9f is incident on the detection elements 16 shown in A to E in FIG. 2, and two wavelengths corresponding to different inspection items are selected depending on each sample. For example, when inspecting a sample in flow cell 9a, use the symmetrical wave λ of 370 nm as shown in Figure 3.
_R1 , 480 nm is the sample wave λ _s , the intensity of the transmitted light is detected by photodiodes A ₁ and A ₂ , and the electric signals E _R and E _S are converted into log1/E _S − by the arithmetic circuit (not shown) of the device. By calculating log1/E _R =ΔA, (ΔA), that is, the absorbance difference can be measured. In this way, the two wavelengths necessary for the analysis items of the sample in each flow cell are arbitrarily selected from the above 340 to 700 nm in rows A to E, and 6 types of analysis can be performed at the same time. It is something that can be analyzed. This method of measuring the absorbance difference of samples in the same flow cell using these two wavelengths is exactly the same as the single-beam dual-wavelength spectrophotometer that has already been developed and is in use, and its high accuracy and other features are will not be explained again. However, the above standard cell and this device, which uses a double beam method to keep the amount of transmitted light constant at 600 nm, suffer from deterioration of the light source lamp, sudden changes in outside temperature, and fluctuations in color temperature in the short wavelength range, as shown in Figure 3. This compensates for fluctuations in the light intensity distribution specific to the light source lamp as shown, always supplies light energy with the correct intensity distribution, and maintains high analytical accuracy.

The above embodiment device is an example in which six flow cells and one standard cell are used as one optical system, and another optical system with the same configuration is provided, but the number of flow cells is not limited to six. . Also, the X axis, Y axis
Although the axes have been described, it goes without saying that a configuration in which these two axes are interchanged is also possible.

This idea is structured as above, so
In the field of automatic biochemical analysis, we have improved the dual-wavelength spectrophotometer, which can test many specimens for many test items at once, to a double-beam method, which is often on standby for emergency testing. We have been able to provide a useful device that constantly automatically compensates for fluctuations in the light energy of the light source lamp, which is prone to deterioration, and fluctuations due to other factors, allowing the lamp to be used for a long time, and allowing stable analytical measurements with good accuracy. be.

[Brief explanation of drawings]

Figure 1 is a front view of the optical system of the multi-channel double beam two-wavelength spectrophotometer of the embodiment, Figure 1 is a plan view of the same, and Figure 2 is the light receiving section of this device, with a light beam corresponding to the standard cell in the center. An explanatory diagram showing a state in which one detection element and 11 photodetection elements corresponding to three sample flow cells on each side are arranged in the Y direction, and two of them are selected according to inspection items. FIG. 3 is an example diagram showing the relative intensity of light energy corresponding to the number of wavelengths of the light source lamp. 1...Light source, 2...Light source lighting voltage controller, 9A
~9F...Sample cell (flow cell), 10...Standard sample cell (filled with pure solvent such as air or water),
X-X...X-axis direction (light source 1 length direction and 9,
10 cell arrangement direction), Y-Y...Y-axis direction (sample cell length direction), 11...Slit long in the X-axis direction, Ba~Bf...spectral band of transmitted light from each cell, Bu~Bl ... Spectral band of each cell transmitted light dispersed in the Y-axis direction (for example, 340 nm ~
700nm), 15...Spectrum light receiving section, S...Photodetection element corresponding to standard sample cell, A to F...Photodetection element corresponding to sample cell (9a to 9f), λ
... Wavelength, e ... Relative intensity of light energy (%), e _s ... (e) of 600 nm (specific spectral intensity of light transmitted through the standard sample).

Claims (1)

[Scope of utility model registration request] A plurality of sample cells are arranged in a row in the X-axis direction,
The transmitted light from each of these sample cells is separated after passing through a long slit in the X-axis direction, and the spectral bands of the separated light transmitted through each sample cell become spectra dispersed in the Y-axis direction. In addition to arranging a wavelength dispersive optical system, a detection section array consisting of at least two detection elements arranged in the Y-axis direction corresponding to each of the sample cells is arranged in one plane at the appearance position of each of the spectral bands. In a multi-channel double-beam dual-wavelength spectrophotometer that is provided with spectrum receiving sections arranged in the X-axis direction in the same number as the sample cells, one standard sample cell is arranged in the column of sample cells. are added and arranged, and at the light receiving part of the spectrum,
One additional detection element is provided corresponding to the one standard sample cell, and the intensity of the specific spectrum of the light transmitted through the standard sample cell is kept constant. A multi-channel double beam two-wavelength spectrophotometer characterized by being equipped with a circuit that automatically controls light source brightness.