JPH05346349A - Automatic chemical analyzer - Google Patents

Abstract

PURPOSE:To prevent mixture of stray light into a monochromatic light which enters each light reception element and to improve measurement accuracy by equipping a light source, a spectroscope, a light reception device, and a filter. CONSTITUTION:A plurality of glare protection layers 11B are provided within a protection member 11. Then, even if one part of monochromatic light entering the member 11 wanders on a transparent layer 11A, it is shielded and absorbed by the glare protection layer 1B, thus preventing monochromatic light which should enter a specified light reception element 3 from being mixed into other elements 3 as stray light. Further, when stray light which is generated by a dispersion element is received by a photo diode array 10 for elimination, a filter for cutting a high-order light is pre-positioned at the array 10 to eliminate stray light which is generated by the dispersion element. In this case, the quantity of stray light is 0.1% or less, thus preventing stray light generated by the protection member of a group of photoelectric conversion element group from being mixed into other monochromatic colors and accurately measuring absorbance of a specimen liquid to be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of biochemical analysis, and is a multi-wavelength measurement in which a large number of light receiving elements for photoelectrically converting dispersed monochromatic light are arranged in a direction in which each monochromatic light is dispersed. A possible automatic chemical analyzer.

[0002]

2. Description of the Related Art As shown in FIGS. 1 and 2, a light-receiving element array, for example, a photodiode array 1 in a conventional automatic chemical analyzer is visible from an ultraviolet region in a recess 2 formed in the upper surface of a case 1A. A large number of light receiving elements 3 sensitive to a predetermined wavelength between regions, for example, a photodiode array are arranged, and an inert gas such as nitrogen gas is filled in the recess 2 to prevent oxidation of the photodiode array. It is a dual imping type that is constructed by sealing with a plate and a plastic plate. In addition, 5 is an output pin. And FIG.
As shown in, the light traveling straight through the slit 6 is split into each monochromatic light by the dispersive element 7, for example, a diffraction grating, and the photodiode array 1 having the above configuration is arranged in the direction in which each monochromatic light is dispersed. For example, the photodiode array 1 measures the absorbance at various wavelengths of light transmitted through the sample solution.

What is important in the photodiode array 1 is that only monochromatic light of a predetermined wavelength is incident on each arrayed photodiode array. This is because if light of other wavelengths enters the photodiode to which monochromatic light of a predetermined wavelength should enter, an error will occur in the absorbance value measured by the photodiode array 1. In particular, filters such as a high-order light cutting filter and a bandpass filter are placed in front of the monochromatic light dispersed by the dispersive element 7.

[0004]

However, in the automatic chemical analyzer equipped with the photodiode array 1,
When you want to measure the absorbance of a sample with high accuracy using monochromatic light in the ultraviolet region such as 0 nm, the light energy of the lamp is small in the ultraviolet region, so if a small amount of light in the visible region enters as confusion light, for example. As a result of a large stray light,
When a large error occurs in the absorbance measurement, although the filter is placed in front to eliminate stray light generated by the dispersive element, a very small amount of monochromatic stray light incident on the photodiode array was mixed. .. As a result of various investigations by the present inventors regarding the cause of this stray light, the protective member 4 disposed on the upper surface of the photodiode array 1 was examined.
Was found to be the cause of stray light.

That is, when monochromatic light from which stray light such as higher-order light of the front filter is removed enters the protective member 4,
Due to the different refractive indexes of the nitrogen gas and the air enclosed in the protective member 4 and the concave portion 2, a part of the incident monochromatic light migrates using the transparent member 4 as a light guide as shown in FIG. That is, the stray light was emitted to another photodiode, and as a result, the stray light was mixed into the monochromatic light that should have been eliminated. However, if the protection member 4 mounted on the photodiode array 1 is removed to remove such stray light, the photodiode is directly exposed to the air, and the photodiode is significantly oxidized. The life of the array 1 will be shortened. Therefore, in the photodiode array 1, a major problem is how to prevent stray light from entering due to the protective member 4. This invention effectively prevents stray light from being mixed into the monochromatic light incident on each light receiving element without removing the protective member enclosing an inert gas in order to prevent oxidation of the photoelectric conversion element. Another object of the present invention is to provide an automatic chemical analysis device with improved measurement accuracy.

[0006]

An automatic chemical analyzer according to the present invention for achieving the above object comprises a light source for irradiating a sample to be measured with light, and a light transmitted through the sample for receiving the light. A spectroscope that disperses and disperses each wavelength included in light, a light receiving device that measures dispersive spectroscopy from this spectroscope for each wavelength, and an incident light of a predetermined wavelength that is arranged in front of this light receiving device is attenuated and transmitted. The photoelectric conversion element group for photoelectrically converting the dispersed spectrum from the spectroscope for each wavelength, a case in which the photoelectric conversion element group is arranged, and the photoelectric conversion element group. In order to protect from the outside air, the photoelectric conversion element has a protective member provided on the case on the light-receiving surface side and having a plurality of light-transmitting portions and light-shielding portions arranged alternately in the dispersion direction of the dispersion spectroscopy. It is a thing.

[0007]

It is possible to effectively prevent stray light generated by the protective member of the photoelectric conversion element group from mixing with other monochromatic light. Therefore, the absorbance of the sample liquid as the measurement target can be measured with high accuracy.

[0008]

FIG. 4 is a perspective view showing an example of a light receiving device according to an embodiment of the present invention, and FIG. 5 is a sectional view of the light receiving device shown in FIG.

As shown in FIG. 4, a light-receiving element array as a light-receiving device in one embodiment of the present invention, for example, a photodiode array 10 is a dual-imping type like the conventional photodiode array 1, and a conventional photodiode is used. The part different from the array 1 is a protective member, and the other parts such as the case 1A, the recessed part 2, the light receiving element 3, and the output pin 5 are the same as the conventional ones. Photodiode array 1 in this embodiment
As shown in FIG. 5, the protective member 11 provided in 0 is formed by laminating a transparent layer 11A and a light shielding layer 11B in a direction in which monochromatic light is dispersed. The transparent layer 11A can be formed of, for example, transparent glass, quartz, or plastic, and the light shielding layer 11B can be formed of black glass, quartz, or plastic. Further, the protection member 11 can be formed, for example, by stacking transparent quartz and black quartz and fusing them. The interval between the light shielding layers 11B can be appropriately determined depending on the allowable amount of stray light mixed into monochromatic light. Shading layer 1
Thickness of 1B (dimension in the direction orthogonal to the incident direction of monochromatic light)
Is preferably thin to the extent that it does not adversely affect the light receiving element 3 that detects incident monochromatic light.

As described above, the light shielding layer 1 is provided in the protective member 11.
By providing a plurality of 1B, even if a part of the monochromatic light incident on the protective member 10 migrates through the transparent layer 11A in the protective member 10, as shown in FIG.
Since it is blocked and absorbed by 1B, the predetermined light receiving element 3
It is possible to prevent the monochromatic light that should be incident on the other light receiving elements 3 from entering as stray light.

Further, when light is received by the photodiode array 10 in order to remove stray light generated by the dispersive element 7, a high-order light cutting filter or a filter for cutting high-order light is provided in the photodiode array 10 in order to remove stray light generated by the dispersive element 7. A filter such as a bandpass filter is placed in advance. According to the experiments by the present inventors, when the conventional photodiode array 10 is used with a filter in front, the amount of stray light is 0.1% or less.

It is needless to say that the present invention is not limited to the above-mentioned embodiment, and each part in the above-mentioned embodiment can be replaced by another member having the same function.

[0013]

According to the present invention, stray light generated by the protective member of the photoelectric conversion element group can be effectively prevented from mixing with other monochromatic light. Therefore, the absorbance of the sample liquid as the measurement target can be measured with high accuracy.

[Brief description of drawings]

FIG. 1 is a perspective view showing a conventional photodiode array.

FIG. 2 is a sectional view showing a conventional photodiode array.

FIG. 3 is an explanatory diagram showing a usage state of a photodiode array.

FIG. 4 is a perspective view showing a photodiode array according to an embodiment of the present invention.

FIG. 5 is a sectional view showing a photodiode array according to an embodiment of the present invention.

[Explanation of symbols]

 3 Light receiving element 7 Dispersion element 10 Photodiode array 11 Protective member 11A Transparent layer 11B Light shielding layer

Claims (1)

[Claims] 1. A light source for irradiating a sample to be measured with light, a spectroscope for receiving light transmitted through the sample and performing a dispersive spectroscopy for each wavelength contained in the transmitted light, and a dispersive spectroscope from the spectroscope. A light receiving device for measuring each wavelength, and a filter arranged in front of the light receiving device for attenuating incident light of a predetermined wavelength and transmitting the light. A photoelectric conversion element group that performs photoelectric conversion for each case, a case in which this photoelectric conversion element group is arranged, and the dispersion provided in the case on the light receiving surface side of the photoelectric conversion element to protect the photoelectric conversion element group from the outside air. An automatic chemical analysis device, comprising: a protective member in which a plurality of light-transmitting portions and light-shielding portions are alternately arranged in a spectral dispersion direction.