JP2014115268A - Spectroscopic analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique that is able to improve absorbance measurement and analysis accuracy and reproducibility.SOLUTION: In a spectroscopic analyzer, an optical system for measuring the absorbance of a sample comprises: a translucent part 220 in which a reaction cell, which is a container for storing the sample, is arranged; an illuminating part 210 including a light source for emitting illumination light to the sample in the container in the translucent part 220; and a photometry part 230 configured to measure the absorbance of the sample by rendering transmitted light from the sample in the container in the translucent part 220 spectroscopic, thereby detecting the intensity of each wavelength. A first optical fiber 240 is provided for connecting the illuminating part 210 and the translucent part 220 and guiding illumination light. A second optical fiber 250 is also provided for connecting the translucent part 220 and the photometry part 230 and guiding translucent light. The partial polarization characteristic of illumination light from a light source is eliminated by the first optical fiber 240 and is emitted to the sample as a non-polarization light.

Description

  The present invention relates to a technique such as a spectroscopic analyzer.

  A spectroscopic analyzer having a function of measuring the absorbance or spectral wavelength intensity of a sample to be analyzed is applied to, for example, an automatic biochemical analyzer that analyzes the amount of components contained in a sample such as blood or urine. Prior art examples relating to a spectroscopic analyzer and the like include U.S. Pat. No. 4,451,433 (Japanese Patent Laid-Open No. 57-82769) (Patent Document 1), Japanese Patent Laid-Open No. 2008-70870 (Patent Document 2), and Japanese Patent Laid-Open No. 8-29293. The gazette (patent document 3) is mentioned.

  Patent Document 1 discloses an automatic analyzer that irradiates a sample or a reaction solution in which a sample and a reagent are mixed with light from a light source, and determines the amount of transmitted light at a single or a plurality of measurement wavelengths that has passed through the sample or reaction solution. A configuration is disclosed in which the light intensity taken in and measured by a diffraction grating is measured by a light receiving element to calculate the absorbance, and the component amount is calculated from the relationship between the absorbance and the concentration.

  In an automatic analyzer such as Patent Document 1, a halogen lamp is widely used as a light source. Halogen lamps are less expensive than light-discharge lamps with little change in the amount of light with time, and can provide an emission spectrum or wavelength band from the ultraviolet region to the near infrared region.

  Patent Document 2 describes that in a depolarizer that is a depolarizing element, a polarized light beam incident on a patterned half-wave plate is substantially depolarized on the image plane. Patent Document 2 discloses that a diffraction grating has inherent polarization sensitivity, and in order to eliminate this, a depolarizer is inserted in front of the diffraction grating to cancel the polarization characteristics of light incident on the diffraction grating. It is described that it is effective to enter non-polarized light.

  Patent Document 3 discloses an example in which the polarization mode dispersion characteristic evaluation of a single mode optical fiber is taken as an example, the polarization characteristic of the light source is eliminated by a depolarizer, and the light is incident on the optical fiber to be measured as non-polarized light.

U.S. Pat. No. 4,451,433 (Japanese Patent Laid-Open No. 57-82769) JP 2008-70870 A JP-A-8-29293

  Conventional spectroscopic analyzers have problems in the accuracy and reproducibility of the results of measurement and analysis of the absorbance of a sample due to differences in characteristics of elements such as a light source and a container constituting the absorbance measurement optical system. In order to improve the apparatus performance, it is necessary to improve the accuracy and reproducibility. It is also desirable to minimize machine differences between devices with the same design specification and to match the measurement results of the same sample between devices with different design specifications.

  The largest factor that fluctuates the measurement result in the optical system of the apparatus is an optical factor, and this optical factor includes a difference in characteristics of the light source and a difference in characteristics of the container. The characteristics of the light source that cause the above include partial polarization characteristics of light emitted from a halogen lamp used as a light source. A device such as Patent Literature 1 uses a halogen lamp as a light source. In the optical system of the apparatus, the partial polarization characteristics may adversely affect the measurement result depending on the measurement target.

  Further, the characteristics of the container as the above factor include birefringence characteristics on the translucent surface of the container due to individual differences of containers for each manufacturer and model, or individual differences of a plurality of containers included in one apparatus. The light passing through the container may be adversely affected by the measurement results.

  As a countermeasure regarding the polarization characteristics, a configuration using a depolarizer that is a depolarization element as in the example of Patent Document 2 is conceivable, but even in this configuration, it is difficult to eliminate fluctuations in absorbance due to the influence of the characteristics of the light source and the container. . Furthermore, a depolarizer that is an optical crystal element is expensive, and the cost of an optical system and apparatus that include the element is greatly increased.

  Moreover, the conventional automatic analyzers such as Patent Document 1 employ a common configuration in which the light source to the diffraction grating are arranged in a straight line as the absorbance measurement optical system. Regarding such a configuration, there is a high demand for miniaturization.

  An object of the present invention is to provide a technique that can improve the accuracy and reproducibility of absorbance measurement and analysis with a low-cost apparatus configuration without the need to use an expensive optical crystal element. is there. Another object of the present invention is a general-purpose absorbance measurement optical system that is not easily affected by differences in the characteristics of light sources and containers, is easily adaptable to the differences, and can be used in common even when the apparatus and model are different. It is to provide technology that can realize. Another object of the present invention is to provide a technique that can contribute to miniaturization of the entire apparatus by realizing miniaturization of the absorbance measurement optical system.

  In order to achieve the above object, a representative embodiment of the present invention is a spectroscopic analyzer, which is characterized by having the following configuration.

  (1) The spectroscopic analyzer of one embodiment has a function of measuring the absorbance or spectral wavelength intensity of a target sample, and the optical system for measuring the absorbance of the sample is a container for storing a substance containing the sample A translucent part in which the light source is disposed; an illumination part including a light source for irradiating illumination light to the sample of the container of the translucent part; A photometric unit that measures the absorbance of the sample by detecting the intensity of the light source, and a first optical fiber that connects the illuminating unit and the translucent unit and guides the illuminating light. The partial polarization characteristic of the illumination light is eliminated by the first optical fiber, and the sample is irradiated as non-polarized light.

  (2) In the spectroscopic analysis apparatus according to (1), the optical system includes a second optical fiber that connects between the light transmitting unit and the photometric unit and guides the transmitted light.

  (3) In the spectroscopic analyzer according to (2), in the optical system, in the light transmitting portion, the emission end of the first optical fiber and the incidence end of the second optical fiber are arranged in a conjugate relationship.

  (4) In the spectroscopic analyzer according to (2), the optical system includes a light transmitting portion in which the exit end of the first optical fiber and the entrance end of the second optical fiber are arranged in an infinite conjugate ratio relationship. Is done.

  (5) The spectroscopic analyzer of one embodiment has a function of measuring the absorbance or spectral wavelength intensity of a target sample, and the optical system for measuring the absorbance of the sample is a container for storing a substance containing the sample A translucent part in which the light source is disposed; an illumination part including a light source for irradiating illumination light to the sample of the container of the translucent part; A photometric unit that measures the absorbance of the sample by detecting the intensity of the sample, and connects the translucent unit with the photometric unit to guide the transmitted light from the sample from the light source that has passed through the container. In addition to eliminating the partial polarization characteristics of the illumination light, variations in the incident optical axis to the photometry unit are eliminated.

  According to a typical embodiment of the present invention, it is possible to improve the accuracy and reproducibility of absorbance measurement and analysis by using a low-cost apparatus configuration without using an expensive optical crystal element. it can. In addition, according to the representative embodiment of the present invention, it is difficult to be affected by the difference in the characteristics of the light source and the container, it is easy to adapt to the difference, and it can be used in common even when the apparatus and the model are different. A general-purpose absorbance measurement optical system can be realized. In addition, according to a typical embodiment of the present invention, the absorbance measuring optical system can be miniaturized and contribute to the miniaturization of the entire apparatus.

It is a figure which shows the planar structure of the biochemical automatic analyzer of Embodiment 1 of this invention. It is a figure which shows the structure of the cell block in the biochemical automatic analyzer of FIG. 1, and a photometry optical axis. FIG. 2 is a diagram showing a schematic block configuration of a spectroscopic analyzer that is a part of the biochemical automatic analyzer of the first embodiment. FIG. 3 is a diagram illustrating a configuration of a light transmitting part of an absorbance measurement optical system of the spectroscopic analysis apparatus according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of an illumination unit of an absorbance measurement optical system of the spectroscopic analyzer according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of a photometry unit of an absorbance measurement optical system of the spectroscopic analyzer according to the first embodiment. It is a figure which shows the structure of the light transmission part of the light absorbency measurement optical system of the spectroscopic analyzer of Embodiment 2 of this invention. It is a figure which shows the structure of the light transmission part of the light absorbency measurement optical system of the spectroscopic analyzer of Embodiment 3 of this invention. FIG. 10 is a diagram illustrating a first state of a photometric optical axis associated with movement of a container in a third embodiment. FIG. 10 is a diagram showing a third state of the photometric optical axis accompanying the movement of the container in the third embodiment. FIG. 10 is a partially enlarged view of the first state of the photometric optical axis in FIG. 9. It is a figure which shows the structure of the incident end surface of the single-line photometry optical fiber used in Embodiment 1-3, and an output end surface. It is a figure which shows the structure of the incident end surface and output end surface of a bundle type optical fiber. FIG. 6 is a diagram illustrating a configuration example of a spectroscopic analysis apparatus including a nonlinear absorbance measurement optical system and an optical path as a modification of the first embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description will be omitted.

<Summary>
The spectroscopic analysis apparatus of the present embodiment shown in FIGS. 3 and 4 etc. irradiates the reaction cell, which is a container for storing the target sample, irradiates the illumination light and separates the transmitted light, and the intensity for each wavelength. By detecting and measuring the absorbance of the sample. As for the automatic analyzer according to the present embodiment, an example in which the spectroscopic analyzer is applied to a biochemical automatic analyzer used for clinical laboratory use will be described. In this configuration, the first optical fiber is disposed between the illumination unit and the light transmission unit in the illumination unit, the light transmission unit, and the light measurement unit that constitute the absorbance measurement optical system, and the light transmission unit and the photometry unit are disposed between the light transmission unit and the light measurement unit. A second optical fiber is disposed. The partial polarization characteristic of the illumination light of the halogen lamp as the light source is canceled by the first optical fiber to make it non-polarized light, and the sample of the reaction cell in the light transmitting part is irradiated. Then, the transmitted light is incident on the photometry section through the second optical fiber, and the intensity of each wavelength is detected and analyzed to measure and analyze the absorbance of the sample. This configuration eliminates or reduces the effects of differences in the polarization characteristics of the light source and the optical characteristics of the light-transmitting surface of the reaction cell, and uses high-precision and reproducible absorbance measurement using inexpensive components such as optical fibers. And analysis is realized.

<Prerequisite technology>
It supplements about the prerequisite technique with respect to the spectroscopic analyzer of this Embodiment, and its subject. An apparatus that is an automatic analyzer or a spectroscopic analyzer has the following configuration as an absorbance measurement optical system employing a common principle. For the sake of explanation, an optical system necessary for measuring absorbance is also referred to as an absorbance measuring optical system. The apparatus irradiates a sample or a reaction solution in which a sample and a reagent are mixed with light from a light source by a halogen lamp, spectrally transmits the light transmitted through the sample with a diffraction grating, and uses a light receiving element or a photodetector for each wavelength. The spectral wavelength intensity, which is the light intensity, is measured to calculate the absorbance, and the component amount is analyzed using the calculated absorbance.

  The apparatus also includes an optical system for illuminating light from a light source on a container storing a sample or a reaction solution, and irradiating the transmitted light to a diffraction grating to guide the light to a light receiving element in order to improve analysis accuracy. Has an optical system. In the description, the former optical system is also referred to as an illumination unit, and the latter optical system is also referred to as a photometry unit. In addition, a portion that is disposed between the illumination unit and the photometric unit and that stores a sample or a reaction solution and transmits light is also referred to as a translucent unit.

  The greatest factor that fluctuates the result of measurement and analysis of the absorbance of the sample in the absorbance measurement optical system of the above apparatus is an optical factor. This optical factor includes a difference in characteristics of the light source and a difference in characteristics of the container. The characteristics of the light source that is the factor include that the polarization characteristics of light emitted from the light source differ depending on the type or type of halogen lamp used as the light source and individual differences. In particular, light emitted from a halogen lamp that is a light source has partial polarization characteristics. In an absorbance measurement optical system using a halogen lamp as a light source, depending on the measurement target, the partial polarization characteristics of the emitted light from the light source may adversely affect the measurement result.

  The light is a transverse electromagnetic wave that vibrates in a direction orthogonal to the traveling direction. For example, the light emitted from the laser oscillator is completely polarized because the phases of the oscillating transverse waves are in a fixed relationship both in time and space. In contrast, natural light is non-polarized because the phase of the traveling wave changes randomly and does not have regularity. Partially polarized light refers to an intermediate state between completely polarized light and non-polarized light.

  In addition, the characteristics of the containers that cause the above factors are that birefringence characteristics occur on the translucent surface of the containers due to individual differences between containers, or the shapes of all containers do not exactly match due to individual differences between containers. Including. There are individual differences in the containers provided in the device for each manufacturer and model. In addition, even in a plurality of containers provided in one device, individual differences may occur although the same shape is aimed at by design. Light emitted from the light source and transmitted through the sample in the container may be adversely affected by the difference in the characteristics of the container, thereby adversely affecting the measurement result.

  In order to improve the performance of spectroscopic analyzers, it is necessary to improve the accuracy and reproducibility of absorbance measurement and analysis, and to be able to cope with fluctuations in measurement results according to differences in equipment, including differences in the characteristics of light sources and containers. is there. It is desirable to minimize machine differences, which are differences in results when the same sample is measured in a plurality of apparatuses having the same design specifications. Moreover, it is desirable that the measurement results of the same sample be consistent among a plurality of apparatuses having different design specifications.

  As a countermeasure against the fluctuation of the polarization characteristic and the measurement result, a configuration using a depolarizer that is a depolarizing element using an optical crystal element as in the example of Patent Document 2 can be considered. In order to make the partially polarized light non-polarized by the depolarizer, it is necessary to precisely position the rotation direction of the depolarizer or the direction of the optical crystal with respect to the incident optical axis. The polarization intensity distribution in the direction orthogonal to the optical axis, which is the polarization state of the light transmitted through the container, varies depending on the light transmission position even in the same container. Even in the same halogen lamp, the polarization state differs depending on the wavelength of light emitted from the filament.

  Therefore, unpolarized light cannot be incident on the diffraction grating even when the depolarizer is inserted in front of the diffraction grating or the light emitted from the halogen lamp is incident on the depolarizer. Therefore, in this configuration, the change in absorbance cannot be completely eliminated. Furthermore, since a depolarizer that is an optical crystal element is expensive, the cost of an absorbance measurement optical system and a spectroscopic analysis apparatus that include the element is greatly increased.

  The absorbance measurement optical system in an automatic analyzer such as Patent Document 1 includes the above-described illumination unit, translucent unit, and photometric unit, and has a common configuration in which the light source to the diffraction grating are arranged in a straight line with the container substantially at the center. It has been adopted. For the sake of explanation, this common configuration is referred to as “linear arrangement” or the like. The illuminating unit includes optical means for condensing light from a halogen lamp as a light source toward a light-transmitting surface of the container. The translucent part includes a part through which light passes through a container in which a sample is stored. The photometry unit includes an optical means for guiding light transmitted through the sample of the container to the diffraction grating.

  However, as a matter of course, the device and its absorbance measurement optical system are uniquely designed for each manufacturer. Even with the same manufacturer, the design specifications of the absorbance measurement optical system including the shape and volume of the container are often different depending on the model. In the case of devices of different manufacturers and models, there are cases in which the absorbance of measurement results does not exactly match even for the same sample. In one apparatus, a plurality of apparatuses having the same design specification, or a plurality of apparatuses having different design specifications, it is desirable that the measurement results of the same sample match and the variation in the measurement results be minimal.

  Further, the conventional apparatus having the above-described linearly arranged absorbance measurement optical system is highly demanded for downsizing the optical system. A larger size in the direction of the linear arrangement is disadvantageous because the size of the device correspondingly increases. By downsizing the optical system, the layout of the components including the optical system in the apparatus can be made more efficient, and downsizing and cost reduction of the entire apparatus can be expected. Further, the downsizing of the optical system can be expected to have a ripple effect such as a reduction in assembly adjustment time of the apparatus including the optical system, that is, a reduction in manufacturing cost and an assembly error, that is, a reduction in machine difference.

  As a conventional example related to the downsizing of the optical system, there is a configuration using an LED (Light Emitting Diode) as a light source. However, LEDs have a narrow emission spectrum width compared to halogen lamps. When an LED is used as a light source of a spectroscopic analyzer, in order to cover the wavelengths necessary for measurement and analysis, it is necessary to arrange a plurality of light sources having different emission spectra and an optical system corresponding to each light source in parallel. is there. Further, the LED has a large light amount drift due to a change in ambient temperature. Therefore, it is necessary to newly add an LED temperature adjustment function to the apparatus. Therefore, in the case of a configuration to which the LED is applied, the optical system cannot be reduced in size and cost. In the range disclosed in the prior art examples, no specific solution is shown for the demand for downsizing of the optical system.

  As described above, in a spectroscopic analyzer, high accuracy and reproducibility are achieved by eliminating or reducing the influence of differences in optical characteristics including the partial polarization characteristics of a halogen lamp serving as a light source and the birefringence characteristics of the translucent surface of the container. It is necessary to realize the measurement and analysis of absorbance by means of. However, in the configuration according to the prior art example, there is a problem that the cost of the apparatus is increased by using expensive parts in the optical system. Further, in this configuration, there is a problem that the measurement result is likely to be adversely affected by the difference in the optical characteristics of the light source and the container, and the measurement result fluctuates, so that it cannot be used as a general-purpose optical system. Further, the configuration of the linear arrangement of the optical system has a problem that the demand for miniaturization cannot be satisfied.

  The spectroscopic analysis apparatus of the present embodiment configures a specific absorbance measurement optical system using an optical fiber having a depolarization function with respect to problems including the polarization characteristics and fluctuations in measurement results. It is known that an optical fiber has a depolarization function, that is, can be used as a depolarization element.

<Embodiment 1>
A biochemical automatic analyzer 100 and a spectroscopic analyzer 200 according to Embodiment 1 of the present invention will be described with reference to FIGS. In the biochemical automatic analyzer 100 and the spectroscopic analyzer 200 according to the first embodiment, the absorbance measurement optical system can measure the absorbance of a biological sample such as blood with high accuracy and reproducibility at low cost, and can contribute to downsizing of the device. An example of realizing is shown.

[Biochemical automatic analyzer]
FIG. 1 shows a planar configuration of the biochemical automatic analyzer 100 according to the first embodiment. For the sake of explanation, the horizontal plane is the X and Y directions, and the vertical direction is the Z direction. The biochemical automatic analyzer 100 roughly includes a control device, a cell disk 101, a sample dispensing mechanism, a reagent dispensing mechanism, a stirring mechanism, a cleaning mechanism, and a spectroscopic analyzer 200. The spectroscopic analysis apparatus 200, as a functional outline, irradiates the reaction solution containing the sample of the reaction cell with the illumination light from the light source, splits the transmitted light, detects the intensity for each wavelength, and calculates the absorbance at the sample. taking measurement.

  In FIG. 1, the outline of the operation of the biochemical automatic analyzer 100 is as follows. A sample from which serum is extracted by centrifuging blood is stored in the sample bottles 112a to 112c and mounted on the sample disk 111 by an operator. The sample bottles 112a to 112c are attached with barcodes for identifying the samples. When the sample disk 111 is rotated as indicated by θ2, the barcode is automatically moved to a barcode reading position (not shown). The code is read.

  (Cell Disc) The cell disc 101 includes a cell block 10. As shown in FIG. 2, the cell block 10 includes reaction cells c <b> 1 to c <b> 7 that are a plurality of containers 1. The cell disk 101 and its container 1 are positioned by rotating the cell disk 101 as indicated by θ1.

  FIG. 2 shows an example of the structure of the cell block 10. FIG. 2A shows a surface of the cell block 10 as viewed from above in the Z direction, which is the horizontal plane of the cell block 10. FIG. 2B shows an XZ plane which is a cross section taken along the line A-A ′ of FIG. The cell block 10 is, for example, a container formed by molding an optically transparent resin such as polypropylene. Through holes 8 and 9 are formed in the flange surface of the cell block 10, and the cell block 10 is screwed and fixed to the cell disk 101 using the through holes 8 and 9.

  The cell block 10 includes a plurality of reaction cells c1 to c7 that are individual containers 1 that can store samples or reaction solutions. The cell block 10 is a structure in which a plurality of reaction cells c1 to c7 are integrally formed on an arc. In the cell block 10, a plurality of reaction cells c1 to c7 having the same shape are arranged in an arc shape on a track L having a predetermined curvature. One container 1 has, for example, a rectangular parallelepiped shape that is long in the Z direction as shown in the drawing, and the upper side in the Z direction is a rectangular opening surface. The radius of curvature of the track L on the outer periphery of the cell disk 101 matches the radius of curvature of a plurality of reaction cells c1 to c7 arranged in a circular arc at regular intervals.

  The biochemical automatic analyzer 100 can position all the reaction cells c1 to c7 on the trajectory L by rotating the cell disk 101 as θ1. Assuming that the A-A ′ line is a photometric optical axis J0 described later, the desired container 1 can be positioned on the photometric optical axis J0 of the A-A ′ line in accordance with the control of the rotation angle of the cell disk 101. As the cell disk 101 rotates θ1, all the reaction cells c1 to c7 move on the trajectory L and pass through the photometric optical axis J0.

  (Sample Dispensing Mechanism) A dispensing nozzle is attached to the tip of the sample dispensing arm 113, and the dispensing nozzle quantitatively sucks the sample from the sample bottle 112 a and discharges it into the container 1 of the cell block 10. The sample dispensing arm 113 is driven by the vertical rotation mechanism 114, and the tip of the dispensing nozzle for which the dispensing operation has been completed is washed by the washing port 115. The dispensing nozzle repeatedly sucks, discharges, and cleans the sample, for example, sequentially dispenses the sample inside the sample bottles 112b and 112c to the reaction cells c2 and c3 of the cell block 10.

  (Reagent dispensing mechanism) Reagents are subsequently dispensed into, for example, reaction cells c1 to c3, which are containers 1 into which a sample has been dispensed. Reagent bottles 122 a to 122 c are mounted on the reagent disk 121, and a reagent, for example, a reagent in the reagent bottle 122 a is selected by the rotation indicated by θ 3 of the reagent disk 121 and positioned immediately below the reagent dispensing arm 123. . A dispensing nozzle is attached to the tip of the reagent dispensing arm 123, and the dispensing nozzle aspirates the reagent from the reagent bottle 122a and discharges the reagent into the container 1 of the cell block 10. The reagent dispensing arm 123 is driven by the vertical rotation mechanism 124, and the tip of the dispensing nozzle for which the dispensing operation has been completed is washed by the washing port 125. The dispensing nozzle repeats suction, discharge, and washing of the reagent, and sequentially dispenses the selected reagent into the container 1, for example, reaction cells c2 and c3.

  (Agitating mechanism) The sample and the reagent dispensed inside the reaction cells c1 to c3, which are containers 1, for example, are agitated for the purpose of promoting the reaction. A stirring bar is attached to the tip of the stirring arm 131, and the stirring bar is inserted into the container 1 and rotated appropriately. The stirring arm 131 is driven by the vertical rotation mechanism 132, and the stirring bar whose stirring operation has been completed is cleaned by the cleaning port 133. The stirring operation is repeated in a similar manner for the reaction cells c2 and c3, which are the plurality of containers 1, for example.

  After completion of the stirring operation, the cell block 10 passes over the light transmitting part 220 of the spectroscopic analyzer 200 at a constant speed. The spectroscopic analyzer 200 measures the absorbance of the target reaction solution inside the reaction cells c1 to c3, which are the plurality of containers 1 of the cell block 10, for example. After completion of the absorbance measurement, the reaction solution is sucked from the inside of the container 1 by the washing nozzle attached to the tip of the washing arm 141, and the inside of the container 1 is washed. The suction and cleaning of the reaction solution are repeated for the plurality of containers 1 in the same manner. The cleaning nozzle can be appropriately cleaned at the cleaning port 143.

  As described above, all device operations in the biochemical automatic analyzer 100 are automatically controlled by a control device (not shown), and the device operations are optimized according to the number of samples to be analyzed and analysis items. In the biochemical automatic analyzer 100 shown in FIG. 1, an example in which only one cell block 10 is attached to the cell disk 101 is shown, but a plurality of cell blocks having the same shape are attached to the cell disk 101. Can do. In addition, an annular constant temperature water tank (not shown) is provided around the cell disk 101 to keep the temperature of the reaction solution stored in the container 1 constant. All of the plurality of containers 1 attached to the cell disk 101 are moved on the track L in FIG. 2 in a state where a part of the containers 1 is immersed in the thermostatic water tank. It passes through the photometric optical axis.

[Spectroscopic analyzer]
FIG. 3 shows a schematic block configuration of a spectroscopic analyzer 200 which is a part of the biochemical automatic analyzer 100 of the first embodiment. The spectroscopic analyzer 200 includes an illumination unit 210, a first optical fiber 240, a translucent unit 220, a second optical fiber 250, and a photometric unit 230 as components of the absorbance measurement optical system. The illumination unit 210 and the translucent unit 220 is connected by a first optical fiber 240, and the light transmitting part 220 and the photometric part 230 are connected by a second optical fiber 250. The first optical fiber 240 is an illumination optical fiber, and the second optical fiber 250 is a photometric optical fiber (also referred to as a detection optical fiber).

  A is the position of the output end of the illumination unit 210 and the input end of the first optical fiber 240. B is the position of the output end of the first optical fiber 240 and the input end of the translucent part 220. C is the position of the output end of the translucent part 220 and the input end of the second optical fiber 250. D is the position of the output end of the second optical fiber 250 and the input end of the photometry unit 230. φA and the like indicate the opening diameter and dimensions. A one-dot chain line indicated by J0 passing through A to D indicates an optical axis of photometry in absorbance measurement. P is an intermediate position of the reaction cell which is the container 1 in the translucent part 220. The illumination unit 210 uses a halogen lamp in particular as a light source. The photometric unit 230 includes a spectroscopic function, and includes a diffraction grating and a photodetector.

  The first optical fiber 240 and the second optical fiber 250 are optical waveguides having a light guiding function and a depolarization function. The first optical fiber 240 and the second optical fiber 250 are optical fibers having a depolarization function. L1 and L2 indicate optical fiber lengths. In particular, the depolarization function of the first optical fiber 240 eliminates the partial polarization characteristics of the halogen lamp that is the light source of the illumination unit 210 and makes it non-polarized.

[Absorbance measurement optical system]
4 shows the configuration of the light transmission unit 220, FIG. 5 shows the configuration of the illumination unit 210, and FIG. 6 shows the configuration of the photometry unit 230 as components of the absorbance measurement optical system of the spectroscopic analyzer 200 of the first embodiment. .

  In the configuration of the absorbance measurement optical system according to the first embodiment, as shown in FIG. 4 and the like, the position BC is a conjugate relationship, the position BP is a conjugate relationship, and the position PC is a conjugate relationship. The core diameter of the first optical fiber 240, the opening diameter φA of the incident end A, and the opening diameter φB of the output end B are, for example, 0.5 mm. The length L1 of the first optical fiber 240 is desirably 50 mm or more. The core diameter of the second optical fiber 250, the opening diameter φC of the incident end C, and the opening diameter φD of the output end D are, for example, 1.0 mm, which is twice that of the first optical fiber 240. The length L2 of the second optical fiber 250 is desirably 50 mm or more. In the first embodiment, the distances a, b, c, d between the positions B, P, C satisfy a <b, c> d.

[Translucent part (1)]
FIG. 4 mainly shows the structure of the light transmitting portion 220 in the absorbance measurement optical system of Embodiment 1 on the XZ plane. In FIG. 4, the reaction solution 11 in which the sample and the reagent are mixed is stored inside the container 1 of the cell block 10, the container 1 is positioned on the photometric optical axis J <b> 0 of the light transmitting unit 220, and the absorbance of the reaction solution 11. Indicates a state of being measured. Reference numeral 221 denotes an annular thermostatic water bath in which the plurality of containers 1 of the cell block 10 are immersed. The constant temperature water tank 221 is provided with an entrance window 224 and an exit window 225 made of quartz material in the middle of a photometric optical axis J0 indicated by a one-dot chain line.

  In FIG. 4, the translucent part 220 extends from the emission end face 242 at the position B of the first optical fiber 240 to the incident end face 251 at the position C of the second optical fiber 250, and does not include the constant temperature water tank 221. The light transmitting unit 220 includes an illumination slit 222, an illumination imaging lens 223, a photometry imaging lens 226, and a photometry slit 227.

[Lighting part]
FIG. 5 mainly shows the structure of the illumination unit 210. The illumination unit 210 includes a halogen lamp 211 as a light source and a condensing elliptical mirror 212. White light emitted from the halogen lamp 211 that is a light source of the illumination unit 210 is collected by the elliptical mirror 212 and enters the incident end surface 241 of the illumination optical fiber 240. The illumination optical fiber 240 is a single-line quartz fiber having a core diameter of 0.5 mm and an aperture ratio of 0.22. The opening dimension (φA) of the incident end face 241 and the opening dimension (φB) of the exit end face 242 of the illumination optical fiber 240 are φ0.5 mm (φ: diameter), similar to the core diameter. Therefore, only a part of the light emitted from the halogen lamp 211 is guided to the light transmitting part 220 in FIG. 4 through the illumination optical fiber 240 and emitted from the emission end face 242.

  Here, the light emitted from the halogen lamp 211 has partial polarization characteristics as described above. This light enters the illumination optical fiber 240 and repeats total reflection within the optical fiber, whereby the partial polarization characteristics are eliminated, and almost complete non-polarized light can be obtained from the emission end face 242. The effect of eliminating the polarization characteristic by the depolarization function of the illumination optical fiber 240 can always be obtained without depending on the polarization characteristic corresponding to the type of the halogen lamp 211 to be used. However, it is desirable that the length L1 from the incident end face 241 to the exit end face 242 that is the entire length of the illumination optical fiber 240 is at least 50 mm or more.

[Translucent part (2)]
Returning to FIG. 4, the outgoing light from the outgoing end face 242 of the illumination optical fiber 240 enters the incident window 224 of the constant temperature bath 221 through the illumination slit 222 and the illumination imaging lens 223 on the photometric optical axis J0. Pass the intermediate position P of the reaction solution 11 in the container 1. The light exits from the exit window 225 of the thermostatic water tank 221 and enters the incident end face 251 of the photometric optical fiber 250 through the photometric imaging lens 226 and the photometric slit 227.

  The illumination imaging lens 223 is made of a quartz material and has a focal length of 15 mm. Due to the illumination imaging lens 223, the emission end face 242 at the position B of the illumination optical fiber 240 has a conjugate relationship with the intermediate position P of the container 1 on the photometric optical axis J0. The slit 222 is a φ5 mm illumination side slit, restricts the opening of the illumination imaging lens 223, suppresses the occurrence of chromatic aberration of the lens, and prevents the generation of stray light during photometry.

  The photometric optical fiber 250 is a single-line quartz fiber having a core diameter of 1 mm and an aperture ratio of 0.22. The opening dimension (φC) of the incident end face 251 and the opening dimension (φD) of the exit end face 252 of the photometric optical fiber 250 are φ1 mm, similar to the core diameter. The incident end face 251 at the position C of the photometric optical fiber 250 is conjugated with the intermediate position P of the container 1 on the photometric optical axis J0 by the photometric imaging lens 226.

  The photometric imaging lens 226 is made of a quartz material and has a focal length of 15 mm. The slit 227 is a photometric side slit of φ5 mm, restricts the aperture size of the photometric imaging lens 226, suppresses the occurrence of chromatic aberration of the lens, and prevents stray light from entering the photometric optical fiber 250. .

  It is assumed that the optical path length on the photometric optical axis J0 of the constant temperature water tank 221 in the X direction is 30 mm, and the refractive index of water in the constant temperature water tank 221 is 1.33. Correspondingly, in the absorbance measurement optical system of the first embodiment, the distance a is 30 mm, the distance b is about 34 mm, the distance d is 30 mm, and the distance c is about 34 mm. The distance a is a distance from the emission end face 242 of the illumination optical fiber 240 to the principal point of the illumination imaging lens 223. The distance b is the distance from the principal point of the illumination imaging lens 223 to the intermediate image position (intermediate position) P, and corresponds to the focal length of the illumination imaging lens 223. The distance c is the distance from the principal point of the photometric imaging lens 226 to the intermediate image position P, and corresponds to the focal length of the photometric imaging lens 226. The distance d is a distance from the incident end face 251 of the photometric optical fiber 250 to the principal point of the photometric imaging lens 226.

  With the above design, the output end face 242 at the position B of the illumination optical fiber 240 and the incident end face 251 at the position C of the photometric optical fiber 250 can be in a conjugate relationship with the intermediate image position P interposed. However, the above-described distances b and c are calculated by ignoring the refractive indexes of the entrance window 224, the exit window 225, and the container 1, and the thickness in the optical axis direction, and thus the detailed values are adjusted as appropriate. .

  Again, due to the configuration of the translucent part 220 as described above, the aperture size (φB = φ0.5 mm) of the emission end face 242 of the illumination optical fiber 240 is 1 times that by the illumination imaging lens 223. An image is formed at point P as an intermediate image of φ0.5 mm. Similarly, the photometric imaging lens 226 forms an image at the point P as an intermediate image of φ1 mm, which is an aperture size (φC = φ1 mm) of the incident end face 251 of the photometric optical fiber 250. That is, the detection-side intermediate image formed at the point P is larger than the illumination-side intermediate image and is doubled. Thereby, the white light transmitted through the reaction solution 11 has an effect of being efficiently taken into the incident end face 251 of the photometric optical fiber 250. The basic condition of the opening dimension is not limited to the above double, and φC may be equal to or greater than φB.

  Further, with the configuration of the light transmitting part 220 as described above, the length from the emission end face 242 at the position B of the illumination optical fiber 240 to the incident end face 251 at the position C of the photometric optical fiber 250 on the photometric optical axis J0 is conventionally increased. It can be significantly shortened than the configuration of. The absorbance measurement optical system of this embodiment and its photometric optical axis J0 are linearly arranged in the X direction, and the distance from position B to position C is about 128 mm from a + b + c + d. This optical system can realize a size that is ½ or less that of a conventional linearly-arranged optical system such as Patent Document 1.

  The illumination imaging lens 223 and the photometric imaging lens 226 are desirably combined lenses such as an achromatic lens or an apochromatic lens that are color-matched in a wavelength band of approximately 340 nm to 800 nm, which is a wavelength band used for absorbance measurement. . In addition, using a single lens instead of a combination lens, the light transmitting part 220 may be designed around 570 nm, which is the center wavelength of the wavelength band used for absorbance measurement.

  In addition, the imaging magnification by the illumination imaging lens 223 and the photometry imaging lens 226 may be varied by adjusting the distances a, b, c, and d on the photometry optical axis J0. . The image forming on the photometry side may be equal to or greater than the image forming on the illumination side. For example, by setting the distance a to 40 mm and the distance b to 28 mm, an image corresponding to the aperture size (φB = φ0.5 mm) of the emission end face 242 of the illumination optical fiber 240 is obtained by the illumination imaging lens 223. An image is formed at the point P as an intermediate image of φ0.35 mm which is .7 times. Further, by setting the distance c to 44 mm and the distance d to 24 mm, an image corresponding to the aperture size (φC = φ1 mm) of the incident end face 251 of the photometric optical fiber 250 is obtained by the photometric imaging lens 226. It is possible to form an image at point P as an intermediate image having a diameter of φ1.67 mm. In the above design example, the intermediate image at point P is 1.67 times on the exit or photometry side with respect to 0.7 times on the entrance or illumination side, and about 2.4 times on the exit side with respect to the entrance side. Become. Thereby, the transmitted light can be efficiently taken into the photometric optical fiber 250.

  Further, the intermediate image between the illumination side and the photometry side is not necessarily the position P of the central portion of the reaction solution 11 of the container 1 on the photometry optical axis J0 in the X direction shown in the figure, or the optical path length (30 mm) of the constant temperature water tank 221. ) In the center position P of the range. That is, the position of the intermediate image may be, for example, the position of the surface of the translucent surface before or behind the position P of the container 1, or the surface of the constant temperature water tank 221 in the constant temperature water tank 221 and the transmission of the container 1. It is good also as a position between optical surfaces.

[Metering unit]
FIG. 6 mainly shows the structure of the photometry unit 230. The photometric unit 230 includes a concave diffraction grating 231 and a photodetector 232. In other words, the concave diffraction grating 231 is a spectroscope, and the photodetector 232 is a light receiving element.

  The white light taken into the above-described photometric optical fiber 250 is guided to the photometric unit 230 and irradiated from the emission end face 252 toward the concave diffraction grating 231. As described above, the opening dimension (φD) at the emission end face 252 of the photometric optical fiber 250 is φ1 mm. The aperture of the photometric optical fiber 250 is used as a spectroscope mask. Accordingly, if a concave diffraction grating 231 of about 1000 lines / mm is used, a wavelength resolution of about 1 nm can be obtained roughly. The light detector 232 can measure the light intensity of each wavelength, that is, the absorbance by spatially dividing and detecting the light diffracted by the concave diffraction grating 231.

  Although not shown in the figure, the photodetector 232 may be further connected to a known element such as a photodiode amplifier or an analog-digital converter, and further connected to an IC or a computer to perform spectral analysis processing, screen display processing, or the like. Also good.

  The photometric optical fiber 250 that is the second optical fiber has a light guiding function and a depolarization function, similarly to the illumination optical fiber 240 that is the first optical fiber. When the incident light is partially polarized light, the concave diffraction grating 231 may affect the detection or absorbance measurement by the photodetector 232, such as variations. In the configuration of the optical system of the present embodiment, partial polarization or the like is eliminated through the first optical fiber 240 and the second optical fiber 250, so that the detection and absorbance measurement accuracy and reproducibility by the photodetector 232 are high. .

[Effects]
As described above, in the absorbance measurement optical system according to the first embodiment, the partial polarization characteristic of the light emitted from the halogen lamp 211 of the illumination unit 210 is eliminated by the illumination optical fiber 240. The influence of optical characteristics including refractive characteristics can be eliminated or reduced, and measurement and analysis with high accuracy and reproducibility can be realized. In addition, it is possible to provide a low-cost and high-accuracy spectroscopic analyzer by the configuration of a specific optical system using an inexpensive optical fiber without requiring a conventional element such as a depolarizer that is expensive and requires high alignment accuracy.

  The absorbance measurement optical system according to the first embodiment includes the illumination unit 210, the light transmission unit 220, and the photometry unit 230, and is a first light that is an optical fiber that can be bent between the modules. The fiber 240 and the second optical fiber 250 are coupled. Therefore, the length of the photometric optical axis J0 of the light transmitting part 220 corresponding to the distance from the position B to the position C can be reduced to about 100 mm, for example, 128 mm. The effect of facilitating mounting on the biochemical automatic analyzer 100 is obtained by the spectroscopic analyzer 200 having the optical system thus miniaturized.

  In addition, the optical system may form a linear optical axis or optical path by arranging each part including the first optical fiber 240 and the second optical fiber 250 as a linear arrangement, or as a non-linear arrangement as an arrangement for bending each optical fiber. An optical axis or an optical path may be configured. As a result, the length of the optical system can be shortened and the apparatus can be reduced in size.

  FIG. 14 shows a configuration example of a spectroscopic analyzer 200 including a nonlinear absorbance measurement optical system and an optical path as a modification of the first embodiment, and shows an example in which the second optical fiber 250 is bent in an arc shape.

  As a modification of the first embodiment, a configuration in which a conventional optical system or another optical system is applied without providing the second optical fiber 250 on the photometric unit 230 side may be employed.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described with reference to FIG. The second embodiment differs from the first embodiment in the configuration of the optical system of the light transmitting section 220 as shown in FIG. In the configuration of the second embodiment, the position B and the position C have an infinite conjugate ratio relationship as shown in FIG. The distances f and g at the distances e, f, g and h between the position B and the position C are arbitrary under the condition that the length (f + g) obtained by adding them is larger than the width of the constant temperature bath 221 or the optical path length. .

  FIG. 7 shows the structure of the translucent part 220, which is a component of the absorbance measurement optical system of the spectroscopic analyzer 200 of the second embodiment, as in FIG. The illumination optical fiber 240 and the photometric optical fiber 250 can be the same as those in the first embodiment. The aperture size (φB) at the emission end face 242 at the position B of the illumination optical fiber 240 is φ0.5 mm, as in the first embodiment. Further, the opening dimension (φC) of the incident end face 251 at the position C of the photometric optical fiber 250 is φ1 mm as in the first embodiment.

  The translucent unit 220 includes an illumination imaging lens 601 and a photometric imaging lens 602 which are different lenses from the first embodiment. The illumination imaging lens 601 is made of a quartz material and has a focal length of 15 mm. This focal length corresponds to the distance e between the emission end face 242 at position B and the principal point of the illumination imaging lens 601. As described above, the slit 222 is a φ5 mm illumination-side slit, restricts the opening of the illumination imaging lens 601, suppresses the occurrence of chromatic aberration of the lens, and prevents the generation of stray light during photometry.

  The photometric imaging lens 602 is made of a quartz material and has a focal length of 15 mm. This focal length corresponds to the distance h between the incident end face 251 at the position C and the principal point of the photometric imaging lens 602. As described above, the slit 227 is a φ5 mm detection-side slit, restricts the aperture size of the photometric imaging lens 602, suppresses the occurrence of chromatic aberration of the lens, and prevents stray light from entering the photometric optical fiber 250. doing.

  In the second embodiment, the distance e which is the dimension on the illumination side on the photometric optical axis J0 in the translucent part 220 is made coincident with the focal length of the illumination imaging lens 601 which is 15 mm, and the dimension on the detection side. This is a configuration in which a certain distance h is matched with 15 mm which is the focal length of the photometric imaging lens 602. Then, the emission end face 242 at the position B of the illumination optical fiber 240 and the emission end face 251 at the position C of the photometric optical fiber 250 are arranged in a relationship of infinite conjugate ratio. Therefore, there is no intermediate image between the illumination side and the detection side at the intermediate point P between the constant temperature water tank 221 and the reaction solution 11 in the container 1.

  The distance f is the distance between the principal point of the illumination imaging lens 601 and the intermediate position P of the container 1. The distance g is the distance between the principal point of the photometric imaging lens 602 and the intermediate position P of the container 1. The distances f and g are variable, but in the example of FIG. 7, when the optical path length of the constant temperature water tank 221 is 30 mm or less, f = g = 15 mm.

  With the configuration of the light transmitting portion 220 as described above, an aperture size (φB = φ0.5 mm) of the exit end surface 242 at the position B of the illumination optical fiber 240 is an intermediate image of φ0.5 mm, which is one time, for photometry. An image is formed on the incident end face 251 at the position C of the optical fiber 250. The opening dimension (φC) of the incident end face 251 at the position C is φ1 mm, which is twice as large as φB. Therefore, in the second embodiment, the white light transmitted through the reaction solution 11 can be efficiently taken into the photometric optical fiber 250 as in the first embodiment.

  According to the configuration of the light transmitting unit 220 and the absorbance measurement optical system in the second embodiment, the distance f and the distance g on the photometric optical axis J0 are emitted from the position B of the illumination optical fiber 240 regardless of the dimensions. The conjugate relationship between the end face 242 and the incident end face 251 at the position C of the photometric optical fiber 250 is theoretically maintained. Therefore, even if the shape and dimensions of the container 1 and the optical path length of the constant temperature water tank 221 change, it is not necessary to change the configuration of the optical system of the light transmitting part 220. That is, even if the type and individual difference of the container 1 and the model of the device including the type of the light source are different, the common optical system of FIG. 7 can be applied, and there is an effect that the machine difference between devices can be suppressed.

  As described above, in the second embodiment, in addition to the effects of the first embodiment, it is possible to further contribute to the miniaturization of the apparatus, and due to the common use of the optical system, the difference in light sources and containers that differ depending on the manufacturer, model, etc. Easy to adapt to.

<Embodiment 3>
Next, Embodiment 3 of the present invention will be described with reference to FIG. The third embodiment is different from the first and second embodiments in that the photometric optical fiber 250 is used instead of the illumination optical fiber 240. That is, the third embodiment has a configuration in which a halogen lamp 211 as a light source is arranged on the photometric optical axis J0 of the light transmitting unit 220. In the third embodiment, a rectangular opening slit 800 is provided at a position B corresponding to the emission end face 242 of the illumination optical fiber 240 described above. Further, in the third embodiment, the above-described photometric slit 227 is removed, and the total luminous flux of the illumination light transmitted through the container 1 can be incident on the photometric optical fiber 250.

[Translucent part]
FIG. 8 mainly shows the configuration of the light transmitting unit 220 in the absorbance measurement optical system of the spectroscopic analyzer 200 of the third embodiment. In the configuration of the third embodiment, a halogen lamp 211 and a rectangular opening slit 800 are provided as the illumination unit 210 in FIG. 8 instead of the illumination unit 210 shown in FIG. On the photometric optical axis J0 in the X direction, the light emitted from the halogen lamp 211 is emitted through the rectangular opening slit 800 and is incident on the illumination side slit 222 of the light transmitting portion 220.

  The rectangular opening slit 800 at the position B has a rectangular opening. The opening dimension (opening B) of the rectangular opening slit 800 is 1 mm × 1 mm in the Y direction × Z direction. The opening size of the illumination side slit 222 is φ8 mm. The focal length of the illumination imaging lens 223 is 15 mm. The focal length of the photometric imaging lens 226 is 15 mm.

  At the distances k, n, q, v between the position B and the position C, the distance k is the distance between the rectangular aperture slit 800 at the position B and the principal point of the imaging lens 223 for illumination. The distance n is the distance between the principal point of the illumination imaging lens 223 and the intermediate position P of the container 1. The distance q is the distance between the principal point of the photometric imaging lens 226 and the intermediate position P of the container 1. The distance v is the distance between the incident end face 251 of the photometric optical fiber 250 at the position C and the principal point of the photometric imaging lens 226.

  In the third embodiment, k = 45 mm, n = 22.5 mm, q = 30 mm, and v = 30 mm in the design of the optical system distances k, n, q, and v. Thereby, the position B and the position C have a conjugate relationship, the position B and the position P have a conjugate relationship, and the position P and the position C have a conjugate relationship.

  The imaging magnification γ1 by the illumination imaging lens 223 is n / k, and n / k = 22.5 mm / 45 mm = 1/2. Therefore, an image corresponding to the opening dimension of the rectangular opening slit 800 (opening B = 1 mm × 1 mm) is reduced by 0.5 times, and a slit image of 0.5 mm × 0.5 mm is formed at the position P as an intermediate image. The The imaging magnification γ2 by the photometric imaging lens 226 is q / v, and q / v = 30 mm / 30 mm = 1. Therefore, the slit image at the position P is formed on the incident end face 251 at the position C of the photometric optical fiber 250 at the same magnification. However, since the distances n and q are calculated by ignoring the refractive index and the thickness in the optical axis direction of the entrance window 224, the exit window 225, the constant temperature water tank 221, the container 1 and the reaction solution 11, detailed values are Adjust as appropriate.

  Here, the incident NA (NA: Numerical Aperture) of the illumination light incident on the container 1 is calculated from the angular magnification α of the illumination imaging lens 223. In addition, regarding the imaging lens 223 for illumination in FIG. 8, u1 is an angle on the incident side determined by the opening dimension of the illumination side slit 222 and the distance k, and u2 is from the opening dimension of the illumination side slit 222 and the distance n. This is the angle on the outgoing side. Further, regarding the photometric imaging lens 226, u2 is the incident-side angle determined from the distance q, similarly to the exit-side angle u2 on the illumination imaging lens 223 side, and u3 is the outgoing-side angle determined from the distance v. It is.

  The angular magnification α of the illumination imaging lens 223 is α = tan (u2) / tan (u1). When the illumination side slit 222 having an aperture size of φ8 mm is close to the illumination imaging lens 223, the diameters of the incident light and the outgoing light of the illumination imaging lens 223 in the Y direction and the Z direction are 8 mm, and tan ( u1) ≈ (8/2) / k = 4 / k = 4/45, tan (u2) ≈ (8/2) /n=4/n=4/22.5. Therefore, u1 = arctan (4 / k) = 0.08 deg (degrees). Further, u2 = arctan (4 / n) = 10.08 deg. In general, the angular magnification α is the reciprocal of the imaging magnification. That is, with respect to the imaging lens 223 for illumination, α = 1 / γ1 = 1 / (1/2) = 2. tan (u2) = α × tan (u1) = 2 × tan (5.08 deg). Therefore, u2 = 10.008 deg.

  The incident NA of the illumination light incident on the container 1 can be obtained by NA = sin (u2). That is, NA = sin (10.08 deg) ≈0.175. The illumination light transmitted through the container 1 is incident on the photometric imaging lens 226 while maintaining the incident NA of about 0.175. Since the imaging magnification of the photometric imaging lens 226 is 1, u2 = u3 = 10.08 deg for the photometric imaging lens 226. As a result, the incident NA of the incident light to the photometric optical fiber 250 is NA = sin (u3) ≈0.175.

  As described above, an intermediate image of 0.5 mm × 0.5 mm is formed at the position P. This intermediate image is formed on the incident end surface 251 of the photometric optical fiber 250 at the same magnification by the photometric imaging lens 226. The incident NA when the illumination light transmitted through the container 1 enters the photometric optical fiber 250 is about 0.175 as described above. On the other hand, the core diameter of the photometric optical fiber 250 is φ1 mm, and the numerical aperture NA is 0.22. The NA (0.22) of the incident end face 251 is larger than the incident NA (0.175).

  In the absorbance measurement optical system of the third embodiment, as an optical condition, the size of the image formed on the incident end face 251 of the photometric optical fiber 250 at the position C is smaller than the core diameter of the photometric optical fiber 250. The incident NA (0.175) of the light beam incident on the incident end face 251 at the position C is smaller than the NA (0.22) of the incident end face 251 of the photometric optical fiber 250. Therefore, the absorbance measuring optical system can make the total luminous flux of the illumination light that has passed through the illumination side slit 222 and transmitted through the container 1 enter the optical fiber 250 for photometry. As long as the optical system satisfies the optical conditions as described above, the entire luminous flux of the transmitted light from the container 1 can be made incident on the photometric optical fiber 250 even in an optical system having different distances and angles. .

  The white light taken into the photometric optical fiber 250 is guided to the photometric unit 230 shown in FIG. 6, and the photometric unit 230 similarly performs spectral measurement and analysis. Since there is no leakage of incident light to the photometry unit 230, the measurement accuracy is high.

  In Embodiment 3, the light emitted from the halogen lamp 211 of the illumination unit 210 has partial polarization characteristics. In addition, the material of the container 1 that becomes the translucent surface of the translucent part 220 has birefringence characteristics. On the other hand, the absorbance measurement optical system including the photometric optical fiber 250 in Embodiment 3 in FIG. 8 has partial polarization characteristics after the illumination light from the halogen lamp 211 passes through the container 1 as described below. It has a configuration that is eliminated.

  When illumination light having an inherent partial polarization characteristic or polarization intensity distribution is transmitted through the container 1, the polarization intensity distribution of the transmitted light changes according to the birefringence characteristics of the material of the container 1. However, if the thickness of the translucent surface that is the translucent portion of the container 1 is constant, the amount of transmitted light does not change.

  The transmitted light enters the photometric optical fiber 250 and repeats total reflection in the photometric optical fiber 250, so that the partial polarization characteristics are eliminated. From the output end face 252 of the photometric optical fiber 250, almost completely is transmitted. Unpolarized light can be obtained. The polarization characteristic cancellation effect by the polarization cancellation function of the photometric optical fiber 250 can always be obtained without depending on the polarization characteristic according to the type of the halogen lamp 211 used as the light source. However, it is desirable to secure at least 50 mm or more of the length L2 from the incident end face 251 to the outgoing end face 252 that is the entire length of the photometric optical fiber 250.

  The concave diffraction grating 231 of the photometry unit 230 affects the detection by the photodetector 232 and the absorbance measurement when the incident light is partially polarized. In the configuration of the optical system according to the third embodiment, partial polarization is eliminated through the photometric optical fiber 250, so that the detection and absorbance measurement accuracy and reproducibility by the photodetector 232 are high.

[Characteristics of container]
The influence of the difference in the optical characteristics of the container 1 in the third embodiment will be described with reference to FIGS. 9 to 11 and FIG. In particular, the birefringence characteristics of the translucent surface of the container 1 will be described. 2, 9, and 10 change as the cell block 10 that moves along with the rotation indicated by θ <b> 1 of the cell disk 101 and the plurality of containers 1 provided therein, and the cell block 10 and the container 1 rotate. The state of the photometric optical axis J0 is shown. The example which changes in order of the 1st state of FIG. 9, the 2nd state of FIG. 2, and the 3rd state of FIG. 10 is shown. The reaction cell c4 of the cell block 10 will be described as an example, but the same applies to the other reaction cells c1 to c3 and c5 to c7.

  First, the state of the photometric optical axis J0 in FIG. 2 described above is the second reference state, and moves in the direction of θ1 on the trajectory L with respect to the linear photometric optical axis J0 in the X direction. The state where the translucent surface of the container 1, for example, the reaction cell c4 is a vertical YZ plane is shown. That is, the photometric optical axis J0 is perpendicular to the light transmitting surface of the reaction cell c4. On the photometric optical axis J0 in the X direction, the light from the illumination unit 210 passes through the translucent surface and the sample before and after the reaction cell c4 and enters the photometric unit 230.

  As shown in FIG. 2, if the photometry optical axis J0 is orthogonal to the translucent surface of the reaction cell c4 that is the container 1, the optical axis after passing through the reaction cell c4 and the principal ray of the light flux are It remains the same as the optical axis before passing through. That is, in the second state, there is no deviation in the photometric optical axis J0.

  FIG. 9 shows a state immediately before the reaction cell c4 reaches the second state in FIG. 2 as a first state, and a state immediately after the start of photometry of the reaction cell c4. When the rotation in the direction of θ1 proceeds from the first state by a predetermined angle, the second state is reached. In this first state, the reaction cell c4 starts to pass with respect to the photometric optical axis J0 in the X direction, and the light transmitting surfaces on the incident side and the emission side of the reaction cell c4 are not perpendicular, and Y shown in the figure. It is in a state tilted slightly to the right.

  FIG. 10 shows a state immediately after the reaction cell c4 exceeds the second state of FIG. 2 as a third state, and is a state immediately before the photometry of the reaction cell c4 is finished. From the second state, the rotation in the direction of θ1 advances by a predetermined angle, so that the third state is reached. In this third state, the reaction cell c4 has finished passing with respect to the photometric optical axis J0 in the X direction, and the light transmission surfaces on the incident side and the emission side of the reaction cell c4 are not perpendicular, It is in a state tilted slightly to the left of the direction.

  FIG. 11 shows an enlargement of the vicinity of the reaction cell c4 in the first state of FIG. In FIG. 11, the reaction cell c4 which is the container 1 has a rectangular cross section in the horizontal direction, and the wall thickness w1 of the four surfaces in the vertical direction is constant, for example, 1 mm. sf1 and sf2 indicate a translucent surface intersecting the photometric optical axis J0 or a center line of its thickness. The translucent surface has a parallel plane shape. The light transmitting surface sf1 on the incident side and the light transmitting surface sf2 on the outgoing side are parallel to each other. The incident-side surface and the emission-side surface in the unit of the light-transmitting surface sf1 are parallel, and the incident-side surface and the emission-side surface in the unit of the light-transmitting surface sf2 are parallel.

  As shown in FIGS. 9, 10, and 11, when the light transmitting surface of the reaction cell c4 and the photometric optical axis J0 are not orthogonal to each other, the light transmitted through the reaction cell c4 due to the action including refraction at the light transmitting surface. The subsequent optical axis is the incident end face 251 of the photometric optical fiber 250 at the position C due to the parallel movement in the Y direction with respect to the optical axis before passing and the change in angle according to the photometric position of the reaction cell c4. The change of the incident position, etc. occurs.

  Examples of parallel movement of the photometric optical axis J0 in the Y direction are indicated by -Δy1 in FIGS. 9 and 11 and + Δy3 in FIG. In FIG. 11, when the optical axis before incidence of the translucent surface sf1 of the reaction cell c4 is J0, the optical axis after incidence of the translucent surface sf1 in the reaction cell c4 and before incidence of the translucent surface sf2 is J1. The optical axis after emission of the translucent surface sf2 of the reaction cell c4 is denoted by J2. The difference between J0 and J2 is Δy1.

  Examples of the change in the incident position at the position C due to the change in the angle are −φ1 that is the angle change in FIGS. 9 and 11, −Δy2 that is the change amount in the Y direction at the position C, and the angle in FIG. 10. This is indicated by + φ3, which is a change, and + Δy4, which is an amount of change in the Y direction at position C. Here, φ indicates a change in the angle of the optical axis.

  The thickness of the translucent surface of the reaction cell c4 is as thin as about 1 mm. Moreover, the water of the reaction solution 11 and the constant temperature water tank 221 exists on the optical axis in the vicinity of the translucent surface. Therefore, when the translucent surface of the reaction cell c4 is a perfect parallel plane, the amount of translation of the photometric optical axis J0, −Δy1 and + Δy3, is as small as about 1 μm.

  However, when the container 1 is processed by a molding method or the like, a dimensional error is generally generated although it is very slight. For this reason, the amount of translation of the optical axis (−Δy1, + Δy3) and the amount of change in the angle of the optical axis (−φ1, + φ3) depend on the shape of the translucent surface of the container 1, and the cell block 10 and As the container 1 moves, it changes irregularly.

  It has been found that the change or behavior of the optical axis when passing through the reaction cells c1 to c7 in the plurality of containers 1 of the cell block 10 is about 1 mrad at the maximum for both φ1 and φ3 with respect to the angle change. Note that 1 mrad = (1/1000) rad = 180 deg / π.

  The curvature radius of the track L of the cell block 10 and the container 1 in the third embodiment is 200 mm. The amount of change of the optical axis transmitted through the container 1 is inversely proportional to the radius of curvature of the trajectory L. In order to suppress the change in the optical axis of the light transmitted through the container 1, the radius of curvature of the trajectory L is increased, the dimensional accuracy of attaching the cell block 10 to the cell disk 101 is increased, and all the reaction cells c1 to c7 have their trajectory L What is necessary is just to make it move on the top with few errors.

  As described above, the optical axis of the transmitted light changes due to the influence of the shape of the translucent surface of the container 1 and the like. The absorbance measurement optical system according to the third embodiment absorbs a change in the optical axis of the transmitted light of the container 1 and makes the total luminous flux of the transmitted light enter the photometric optical fiber 250 by a design that satisfies the optical conditions described above. be able to.

[Optical fiber for photometry]
FIG. 12 shows the YZ plane of the incident end face 251 at the position C of the photometric optical fiber 250 of the third embodiment. The metering optical fiber 250 is a single optical fiber. The photometric optical fiber 250 has a core 253, a clad 254, and a protective coating 255. The diameter of the core 253 is φ1 mm. On the incident end face 251 at the position C of the photometric optical fiber 250, the image 810a, which is a slit image having an opening dimension of 1 mm × 1 mm of the rectangular opening slit 800 described above, is reduced to an image 810b having a size of 0.5 mm × 0.5 mm. Then, an image is formed and incident on a core 253 having a diameter of 1 mm.

  In the optical system of FIG. 8 described above, the distance q and the distance v on the side transmitted through the container 1 are both 30 mm. Therefore, for example, when the optical axis of the light transmitted through the container 1 is inclined at an angle of -1 mrad in the XY plane (1 mrad≈0.06 deg), that is, when φ1 = 1 mrad in FIG. Δy2, which is the amount of change in the incident position, is 0.06 mm.

  Thus, as shown in FIG. 12, an image 810 b having a size of 0.5 mm × 0.5 mm based on the slits on the incident end face 251 and the circular core 253 at the position C of the photometric optical fiber 250 is as shown in an image 811. Move by -Δy2.

  The diameter of the core 253 of the photometric optical fiber 250 according to the third embodiment is designed to be sufficiently larger than the image 810b after the movement, assuming fluctuations in the optical axis and imaging. In other words, the image 810b after the movement is designed to be included in a circular region of the YZ plane of the core 253. The diameter of the core 253 that satisfies this condition is 1 mm.

  Further, as in the optical conditions described above, the incident NA 0.175 of the light beam incident on the incident end face 251 at the position C is smaller than 0.22 which is the aperture ratio of the incident end face 251 of the photometric optical fiber 250. . The NA, which is the aperture ratio of the photometric optical fiber 250, is assumed to be sufficiently large with respect to the incident NA, assuming the occurrence of the optical axis angle inclinations (φ1, φ3) as shown in FIGS. Designed.

  In Embodiment 3, it is assumed that the inclinations (φ1, φ3) of the angles are both 1 mrad. 1 mrad which is the inclination of this angle is added to the angle u3 = u2 = 10.008 deg on the photometric imaging lens 226 side. The incident NA at the time when the illumination light transmitted through the container 1 enters the photometric optical fiber 250 is NA≈0.175 + 0.001 = 0.176, which is about 0.176. The incident NA of about 0.176 is sufficiently smaller than NA = 0.22 which is the aperture ratio of the photometric optical fiber 250. Therefore, in the third embodiment, even if the optical axis of the illumination light transmitted through the container 1 fluctuates, the entire luminous flux of the transmitted light can always be incident on the photometric optical fiber 250 and taken in.

  In addition, the concave diffraction grating 231 of the photometry unit 230 may affect the detection and absorbance measurement by the photodetector 232 if the incident optical axis fluctuates. However, in the configuration of the optical system according to the third embodiment, The light quantity fluctuation due to the fluctuation of the incident optical axis is eliminated through the photometric optical fiber 250. Therefore, the third embodiment has high accuracy in detection and absorbance measurement by the photodetector 232.

  In the above description, the phenomenon only in the XY plane is mentioned with respect to the change of the optical axis of the illumination light transmitted through the container 1. This change in the optical axis of the transmitted light can occur in the XZ plane as well, but can be considered in the same manner as the phenomenon in the XY plane described above.

  FIG. 13 shows, as a supplement and a comparative example, the structure of a general incident end face of an optical fiber 900 called a bundling type or bundle type. The optical fiber 900 has a structure in which, for example, a plurality of optical fibers 901 having a diameter of about 0.05 mm are bundled and fixed with an adhesive to form a large light receiving surface. Therefore, in the region of the incident surface of the optical fiber 900, there is a portion that does not transmit light, corresponding to the adhesive portion, between the optical fibers 901 that are the respective strands. If the transmitted light corresponding to the image 810b shown in FIG. 12 is incident on the incident surface of the optical fiber 900 of FIG. 13, all of the incident light flux cannot be incident on the optical fiber 900, and the above non-existing There is a light loss due to the transmission part.

  Furthermore, when the position of the image 810b changes as shown in FIG. 12 as the container 1 moves, the amount of light emitted from the emission end of the optical fiber 900 changes. This leads to a particularly remarkable light amount change when the spatial light amount distribution of the image 810b is not uniform. As a result, the accuracy of detection and absorbance measurement by the photodetector 232 decreases.

  Therefore, including the above consideration, the photometric optical fiber 250 of the third embodiment is preferably not a bundled optical fiber but a single optical fiber having a single core 253 as shown in FIG. .

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  DESCRIPTION OF SYMBOLS 1 ... Container, c1-c7 ... Reaction cell, 10 ... Cell block, 11 ... Reaction solution, 100 ... Biochemical automatic analyzer, 101 ... Cell disc, 200 ... Spectroscopic analyzer, 210 ... Illumination part, 211 ... Halogen lamp, 212 ... Elliptic mirror, 220 ... Translucent part, 221 ... Constant temperature water tank, 222 ... Illumination slit, 227 ... Photometry slit, 223 ... Illumination imaging lens, 224 ... Entrance window, 225 ... Exit window, 226 ... For photometry Imaging lens 230 ... Photometry section, 231 ... Concave diffraction grating, 232 ... Photo detector, 240 ... First optical fiber (illumination optical fiber), 241 ... Incident end face, 242 ... Outlet end face, 250 ... Second optical fiber (Optical fiber for photometry), 251... Entrance end face, 252... Exit end face, 800... Rectangular opening slit, 810a, 810b.

Claims (18)

A spectroscopic analyzer having a function of measuring the absorbance of a target sample,
The optical system for measuring the absorbance of the sample is:
A translucent part in which a container for storing the sample is disposed;
An illumination unit including a light source for irradiating illumination light to the sample of the container of the translucent unit;
A photometric unit that measures the absorbance of the sample by spectroscopically analyzing the transmitted light from the sample of the container of the translucent unit and detecting the intensity for each wavelength;
A first optical fiber that guides the illumination light by connecting between the illumination unit and the translucent unit,
A spectroscopic analyzer that irradiates the sample as non-polarized light by eliminating partial polarization characteristics of illumination light from the light source by the first optical fiber. The spectroscopic analyzer according to claim 1.
The optical system for measuring the absorbance of the sample is:
A spectroscopic analyzer having a second optical fiber that connects between the light transmitting part and the photometric part and guides the transmitted light. The spectroscopic analyzer according to claim 2,
The optical system is a spectroscopic analyzer in which the emission end of the first optical fiber and the incidence end of the second optical fiber are arranged in a conjugate relationship in the light transmitting section. The spectroscopic analyzer according to claim 3.
In the optical transmission unit, the intermediate image position of the output end of the first optical fiber coincides with the intermediate image position of the incident end of the second optical fiber in the light transmitting portion, and the first optical fiber And the intermediate image position are arranged in a conjugate relationship, and the incident end of the second optical fiber and the intermediate image position are arranged in a conjugate relationship. The spectroscopic analyzer according to claim 3.
The optical analysis device according to claim 1, wherein the light transmitting section has an opening size of an incident end of the second optical fiber equal to or greater than an opening size of an output end of the first optical fiber. The spectroscopic analyzer according to claim 4,
In the optical system, the size of the intermediate image at the incident end of the second optical fiber is equal to or greater than the size of the intermediate image at the output end of the first optical fiber in the light transmitting portion. , Spectroscopic analyzer. The spectroscopic analyzer according to claim 2,
The optical system is a spectroscopic analyzer in which, in the light transmitting part, an emission end of the first optical fiber and an incident end of the second optical fiber are arranged in a relationship of infinite conjugate ratio. The spectroscopic analyzer according to claim 7,
The optical analysis device according to claim 1, wherein the light transmitting section has an opening size of an incident end of the second optical fiber equal to or greater than an opening size of an output end of the first optical fiber. The spectroscopic analyzer according to claim 2,
In the optical system, the illumination unit, the first optical fiber, the translucent unit, the second optical fiber, and the photometry unit are linearly arranged by linear arrangement of the first optical fiber or the second optical fiber. Spectroscopic analyzer that forms an optical path. The spectroscopic analyzer according to claim 2,
In the optical system, the illumination unit, the first optical fiber, the translucent unit, the second optical fiber, and the photometric unit are arranged in a non-linear arrangement of at least one of the first or second optical fiber, A spectroscopic analyzer that forms a non-linear optical path. The spectroscopic analyzer according to claim 1.
The spectroscopic analyzer, wherein the light source of the illumination unit is a halogen lamp. The spectroscopic analyzer according to claim 2,
A cell disk for holding and positioning a plurality of reaction cells as the container, and a thermostatic chamber for storing the container,
The translucent portion transmits a first slit and a first lens for allowing light emitted from the first optical fiber to enter the container, and allows the light emitted from the container to pass through the first optical fiber. A second lens and a second slit for entering the two optical fibers,
The photometric unit includes a diffraction grating that splits light emitted from the second optical fiber, and a photodetector that detects the spectrum from the diffraction grating. A spectroscopic analyzer having a function of measuring the absorbance of a target sample,
The optical system for measuring the absorbance of the sample is:
A translucent part in which a container for storing the sample is disposed;
An illumination unit including a light source for irradiating illumination light to the sample of the container of the translucent unit;
A photometric unit that measures the absorbance of the sample by spectroscopically analyzing the transmitted light from the sample of the container of the translucent unit and detecting the intensity for each wavelength;
An optical fiber that guides the transmitted light by connecting between the light transmitting unit and the photometric unit,
A spectroscopic analysis device that eliminates partial polarization characteristics of illumination light from the light source that has passed through the container by the optical fiber and guides it to the photometry unit as non-polarized light. The spectroscopic analyzer according to claim 13,
The spectroscopic analyzer, wherein the light source of the illumination unit is a halogen lamp. The spectroscopic analyzer according to claim 13,
The optical fiber is a single-line optical fiber. The spectroscopic analyzer according to claim 13,
The optical system has a slit for passing a part of the light emitted from the light source,
A spectroscopic analyzer in which the slit and the incident end of the optical fiber are in a conjugate relationship. The spectroscopic analyzer according to claim 16,
The optical system is configured such that, in the light transmitting portion, the exit end of the slit and the intermediate image position of the exit end of the slit are arranged in a conjugate relationship, and the intermediate image position of the exit end of the slit and the incidence of the optical fiber A spectroscopic analyzer in which the ends are arranged in a conjugate relationship. The spectroscopic analyzer according to claim 16,
The optical system has passed through the slit and the container because the size of the image of the slit formed at the incident end of the optical fiber is smaller than the core diameter of the incident end of the optical fiber. A spectroscopic analyzer in which a total luminous flux of light is incident on the optical fiber.

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