JP2007127449A - Measuring container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring container capable of measuring a liquid sample with high precision even if miniaturized. <P>SOLUTION: The measuring container 2 has a liquid holder 2a for holding a liquid sample and is used in an analyzing optical device. The liquid holder is arranged to the front of the measuring container and molded into a triangular prism shape having transmission part 4 for transmitting a luminous flux and a plurality of reflecting parts 3a and 3b for reflecting the luminous flux transmitted through the transmission part to be incident. The transmission part has a reflecting part, which reflects light to the luminous flux transmitting part and the part adjacent thereto, formed thereto. The liquid holder has a right-angled isosceles triangle in the cross sectional shape cut in a horizontal direction and one side or oblique side of equal sides is arranged in the transmission part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a measurement container used in an analysis optical apparatus.

  Conventionally, an analysis optical device that optically analyzes a liquid sample, for example, a biochemical analysis device that performs component analysis of a collected body fluid or the like, performs analysis using absorption spectroscopy that measures the absorption spectrum of the liquid sample. (For example, refer to Patent Document 1). At this time, the absorption spectroscopy basically obtains the concentration of the target component in the liquid sample based on the Lambert-Beer law.

JP 2001-91455 A

  By the way, the biochemical analyzer disclosed in Patent Document 1 can be sufficiently measured and analyzed if the liquid sample held by the reaction tube (cuvette) is 60 μL. However, in the biochemical analyzer of Patent Document 1, when the reaction tube (cuvette) is made small in order to further reduce the amount of the liquid sample, the optical path length of the light beam transmitted through the liquid sample is shortened accordingly. There is a problem that the accuracy of the measured value is lowered.

  The present invention has been made in view of the above, and an object of the present invention is to provide a measurement container that can measure a liquid sample with high accuracy even if it is small.

  In order to solve the above-described problems and achieve the object, a measurement container according to claim 1 is a measurement container having a liquid holding unit for holding a liquid sample and used in an analytical optical apparatus, and the liquid The holding unit is disposed in front of the measurement container, and has a transmissive part that transmits a light beam, and a triangular prism having a plurality of reflecting parts that reflect the light beam that is transmitted through the transmissive part and is incident and then exits from the transmissive part. It is formed into a shape.

  In the measurement container according to a second aspect of the present invention, in the above invention, the transmissive portion is formed with a reflective portion that reflects light at a portion adjacent to the portion through which the light flux is transmitted.

  Further, in the measurement container according to claim 3, in the above invention, the liquid holding unit has a horizontal isosceles cross-sectional shape that is a right-angled isosceles triangle, and one side of the equilateral side is disposed in the transmission unit. Features.

  The measuring container according to claim 4 is characterized in that, in the above invention, the liquid holding part has a horizontal isosceles cross-sectional shape that is a right-angled isosceles triangle, and a hypotenuse is disposed in the transmission part. To do.

  Further, in the measurement container according to claim 5, in the above invention, the transmission unit and the plurality of reflection units are arranged in a vertical direction, and the liquid holding unit transmits the light flux that passes through the held liquid sample. The optical path length is kept constant.

  In the measurement container according to the present invention, the liquid holding part is disposed on the front surface of the measurement container, and the transmission part through which the light beam is transmitted and the light beam transmitted through the transmission part is reflected and emitted from the transmission part. Since it is formed in a triangular prism shape having a plurality of reflecting portions, the same optical path length as that of the prior art can be secured, and the liquid sample can be measured with high accuracy even if the size is reduced.

(Embodiment 1)
Hereinafter, Embodiment 1 concerning the measuring container of this invention is demonstrated in detail, referring drawings. FIG. 1 is a schematic configuration diagram illustrating a measurement container according to Embodiment 1 and an analysis optical device using the measurement container. FIG. 2 is a plan view showing the measurement container shown in FIG. 1 together with schematic configurations of a light projecting optical system and a light receiving optical system. FIG. 3 is an enlarged view of a portion A in FIG.

  As shown in FIG. 1, the analysis optical device 1 includes a measurement container 2, a light projecting optical system 6, and a light receiving optical system 7, and reflects the light beam emitted from the light projecting optical system 6 by the measurement container 2. Light is received by the light receiving optical system 7, and the concentration of the target component in the liquid sample is calculated by the arithmetic control unit 8.

  As shown in FIGS. 1 and 2, the measurement container 2 of the present invention has a main body 3, a cover 4, and a bottom plate 5, has a triangular prism shape in which a horizontal section is a right-angled isosceles triangle, and has an open top. A plurality of holding portions 2a are provided. When measuring a liquid sample, the measurement container 2 is installed in the analyzer so as to be movable in a predetermined direction (arrow direction shown in FIG. 1) in the analyzer, with the main body 3, the cover 4 and the bottom plate 5 held together. . For this reason, the movement operation of the measurement container 2 is controlled by the control means on the analyzer side. However, it is desirable that the measurement container 2 has a structure in which the main body 3, the cover 4, and the bottom plate 5 are not fixedly and integrally held, but are separable from each other.

  The main body 3 has a plurality of recesses to be the liquid holding portion 2a, and the liquid holding portion 2a surrounded by the cover 4 and the bottom plate 5 is formed. The main body 3 is formed with reflecting portions 3a and 3b by mirror-finishing the surface of each recess formed by processing metal. At this time, the main body 3 may form the reflective portions 3a and 3b by processing the concave portion so as to have a highly accurate plane with small surface roughness and then providing a reflective film on the plane on which the concave portion is formed. The cover 4 is a light beam transmitting portion made of a plate material having high rigidity and translucency, for example, a quartz plate. The bottom plate 5 is a member on which the main body 3 and the cover 4 are placed to form a plurality of liquid holding portions 2a, and the upper surface is formed flat.

  Here, although six liquid holding parts 2a are illustrated in FIG. 1, the number is not limited to six. Further, the liquid holding portion 2a is formed into a triangular prism shape whose horizontal cross section is a right-angled isosceles triangle, but the horizontal cross-sectional shape is not necessarily an accurate right-angled isosceles triangle. For example, the liquid holding unit 2a may slightly increase or decrease the base angle α shown in FIG. 2 from 45 °.

  However, in the measurement container 2, the light beam incident on the liquid holding unit 2a is reflected three times by the reflection units 3a and 3b, and the image of the light source is formed on the reflection unit 3b that reflects 2 {= (3 + 1) / 2} th. It arrange | positions with respect to the light projection optical system 6 so that it may. As a result, the light beam that has reached the reflecting portion 3 b is reflected by the reflecting portion 3 b, is reflected again by the reflecting portion 3 a, passes through the cover 4, and enters the light receiving optical system 7.

  In the light projecting optical system 6, a light source 61, a condenser lens 62, a diaphragm 63 having an aperture, and a projection lens 64 are arranged in this order along the optical axis AL6. The light projecting optical system 6 is arranged so that the optical axis AL6 intersects with the front surface of the measurement container 2 at an angle of about 80 to 88 ° which is smaller than a right angle.

  The light source 61 emits a light beam from a predetermined wavelength band, for example, from near ultraviolet to near infrared. As the light source 61, it is desirable to use a xenon lamp having a small light emitting portion. The condenser lens 62 forms an image of the light beam emitted from the light source 61 on the aperture of the diaphragm 63. Accordingly, the diaphragm 63 is disposed at a position optically conjugate with the light source 61 with respect to the condenser lens 62, and an image of the light source 61 is formed at this position as a secondary light source 61a. The projection lens 64 is a lens that collects the light beam emitted from the light source 61 that has passed through the diaphragm 63 and projects it onto the liquid holding unit 2a, and it is desirable that the numerical aperture (NA) on the emission side is small. It is desirable that it is 0.1 or less.

  Here, the measurement container 2 is moved in the direction of the arrow shown in FIG. 1 when measuring the liquid sample, and the light beams emitted from the light projecting optical system 6 are sequentially incident on the liquid samples held by the liquid holding units 2a. The Further, the point where the optical axis AL6 intersects with the stop 63 and the point P1 where the extended line of the optical axis AL6 intersects the reflecting portion 3b are at optically conjugate positions with respect to the projection lens 64. For this reason, the secondary light source 61a focused on the aperture of the stop 63 is focused on the point P1. Here, the light projecting optical system 6 may be provided with a filter that limits the wavelength band of the emitted light to a predetermined range, for example, between the diaphragm 63 and the projection lens 64.

  In the light receiving optical system 7, a relay lens 71, a slit 72, a concave diffraction grating 73, and a photodetector 74 are arranged along the optical axis AL7 from the incident side of the light beam.

  In the light receiving optical system 7, the optical axis AL7 is positioned on the extension of the optical axis AL6 with respect to the reflecting portions 3a and 3b. The relay lens 71 forms an image of the secondary light source 61 a formed at the point P 1 at the position of the slit 72. The slit 72 is at a position optically conjugate with the point P 1 on the reflection portion 3 b with respect to the relay lens 71, and is disposed so as to contact the Roland circle of the concave diffraction grating 73 together with the photodetector 74. The concave diffraction grating 73 is a reflection having a grating groove in a direction perpendicular to the plane including the optical axis AL7 and the center of the Roland circle whose diameter is the radius of the concave surface of the concave diffraction grating 73 (direction perpendicular to the paper surface of FIG. 2). Type diffraction grating. The photodetector 74 has a plurality of photosensors arranged in a direction perpendicular to the direction of the slit 72 (a direction parallel to the paper surface of FIG. 2). For example, a photodiode array or a one-dimensional CCD (charge coupled) Element) An image sensor or the like can be used. The photodetector 74 outputs information related to the amount of detected light to the arithmetic control unit 8. Here, the optical axis AL7 indicates a propagation path after the light beam propagating through the light projecting optical system 6 is reflected in the liquid holding unit 2a. For this reason, as shown in FIG. 3, when the base angle α of the liquid holding portion 2a is 45 °, the optical axis AL7 is symmetrical with the optical axis AL6 with respect to a perpendicular line dropped from the point P2 to the cover 4.

  The calculation control unit 8 controls the emission of the light beam by the light source 61 in the light projecting optical system 6 and calculates the component concentration of the liquid sample held in the liquid holding unit 2 a based on the amount of light received by the light receiving optical system 7. For example, a microcomputer or the like is used.

  In the analysis optical apparatus 1 configured as described above, a predetermined amount of specimen and reagent are sequentially injected from above into the liquid holding unit 2a surrounded by the main body 3, the cover 4, and the bottom plate 5. The injection amount is an amount that provides a liquid level that allows the measurement light beam to pass therethrough.

  Next, as shown in FIG. 2, a light beam is incident on the liquid holding unit 2 a through the cover 4. Then, the incident light beam passes through the liquid sample containing the specimen and the reagent while being reflected by the reflecting portions 3 a and 3 b, and then is emitted from the measurement container 2 through the cover 4. Next, the light beam emitted from the measurement container 2 enters the light receiving optical system 7, and information on the analysis result regarding the light amount detected by the photodetector 74 is output to the arithmetic control unit 8.

  The calculation control unit 8 calculates the concentration of the predetermined component in the liquid sample based on the Lambert-Beer law based on the analysis result information regarding the light quantity input in this manner. In this measurement, the measurement container 2 is provided with a plurality of liquid holding portions 2a, and therefore is sequentially moved along the arrangement direction of the plurality of liquid holding portions 2a indicated by arrows as shown in FIG. Thereby, the analysis optical apparatus 1 repeats the optical measurement with respect to the liquid sample hold | maintained at the some liquid holding | maintenance part 2a. At this time, the measurement container 2 may inject different samples into the plurality of liquid holding units 2a. For example, in the case of blood analysis or the like, blood collected from the same subject is divided into predetermined amounts. A reagent corresponding to each test item may be added to the blood.

  After a series of measurements are completed in this way, the liquid sample held in each liquid holding part 2a is extracted from the measurement container 2. At this time, if the measurement container 2 has a configuration in which the main body 3, the cover 4, and the bottom plate 5 can be individually separated, first, the bottom plate 5 is separated, and the liquid sample is dropped from the plurality of liquid holding portions 2a. Next, after separating the cover 4 from the main body 3, each of the main body 3, the cover 4, and the bottom plate 5 is washed, and these are reused. As described above, if the measurement container 2 has a structure in which the main body 3, the cover 4, and the bottom plate 5 can be individually separated, the liquid sample can be easily discarded and the separated components can be easily cleaned.

  At this time, in the light projecting optical system 6, the light beam emitted from the light source 61 forms an image of the light source 61 at the position of the diaphragm 63 by the condenser lens 62. That is, in the light projecting optical system 6, a secondary light source 61 a that is an image of the light source 61 is formed at the position of the diaphragm 63. At this time, the size of the secondary light source 61 a is limited by the size of the aperture of the diaphragm 63. Then, the light beam that has passed through the diaphragm 63 where the secondary light source 61a is formed passes through the cover 4 through the projection lens 64 toward the corresponding liquid holding unit 2a of the measurement container 2.

  The light beam transmitted through the cover 4 is reflected by the reflecting portion 3a corresponding to the hypotenuse of the right isosceles triangle and forms an image on the reflecting portion 3b which is one of the equilateral sides. At this time, the light projecting optical system 6 appropriately sets the diameter of the diaphragm 63 and the magnification of the projection lens 64 so that the formed image of the diaphragm 63 falls within the region of the reflecting portion 3b. That is, all the light beams that have passed through the projection lens 64 reach the reflecting portion 3b except for the minute amount of absorption by the liquid sample and diffraction and scattering, and are reflected by the reflecting portion 3b. The light beam reflected by the reflecting portion 3 b is reflected again by the reflecting portion 3 a, passes through the cover 4, and enters the light receiving optical system 7.

  Here, in the measurement container 2, the incident light beam that has passed through the cover 4 is reflected by the reflecting portions 3 a and 3 b, passes through the cover 4 again, and passes through the liquid sample while being transmitted through the liquid sample. Absorption is performed according to the concentration of the target component in the sample. In particular, light having a specific wavelength corresponding to the target component is strongly absorbed.

  On the other hand, in the light receiving optical system 7, the light beam emitted from each liquid holding unit 2 a of the measurement container 2 forms an image of the secondary light source 61 a formed on the reflection unit 3 b by the relay lens 71 on the slit 72. . The light beam that has passed through the slit 72 enters the concave diffraction grating 73 and undergoes reflection diffraction. The light reflected and diffracted by the concave diffraction grating 73 travels in a different direction for each wavelength and forms an image formed on the slit 72 on the surface of the photodetector 74. In the photodetector 74 shown in FIG. 2, this state is shown for three different representative wavelengths. The photodetector 74 detects the intensity of light incident on the optical sensor for each channel. The detected light intensity for each channel is output to the calculation control unit 8, and the concentration of the predetermined component in the liquid sample is calculated.

  At this time, the reference incident light intensity is obtained by injecting a reference liquid that can substantially ignore absorption into the liquid holding unit 2a and performing the same measurement as described above. When measured in this way, the influence of the reflectance at the reflecting portions 3a and 3b in the liquid sample and the reference liquid can be ignored in the calculation. Strictly speaking, the optical path length is slightly different between on-axis light existing on the optical axis and ambient light and off-axis light deviating from the optical axis, but the size of the secondary light source 61a is small, and the projection is performed. Since the numerical aperture (NA) on the exit side of the lens 64 is also small, it can be represented by the optical path length of the axial light in practice.

On the other hand, the optical path length L along the optical axis AL6 and the optical axis AL7 in each liquid holding portion 2a is a measurement of the optical axis AL6 as a length of a side sandwiching a right angle of the liquid holding portion 2a as shown in FIG. Assuming that the incident angle of the container 2 to the cover 4 (the angle between the optical axis AL6 and the normal of the cover 4) is θ, the following equation is given. Here, in FIG. 3, a point P2 is a point that is in a plane-symmetrical position with respect to the point P1 with respect to the reflecting portion 3a, and a point P3 is a perpendicular leg that is lowered from the point P2 to the cover 4. P4 is an intersection of the optical axis AL6 and the cover 4 on the liquid holding unit 2a side. Therefore, in ΔP2P3P4, P2P3 = a, P2P4 = L / 2, and ∠P4P2P3 = θ,
L = 2a / cosθ (∵cosθ = a / (L / 2)
≒ 2a …………………… (1)

Further, when the liquid level of the liquid sample injected into the liquid holding portion 2a is a, the volume V of liquid sample bottom area is held from a ^2/2, the liquid holding portion 2a of the liquid holding portion 2a next It is given by the formula.
^{V = a 2/2 · a} = a 3/2 ..................... (2)

On the other hand, a conventional photometric cell in which a light beam is incident from one side surface of a rectangular parallelepiped cell and is emitted from the other opposite side surface has a depth (= optical path) along the incident direction of the light beam with respect to the internal method. long) b, the width b / 2 perpendicular to the incident direction of the light beam, when the liquid level of the liquid sample to b / 2, the volume Vf of the liquid sample becomes b ^3/4. At this time, since the optical path length needs to be the same in the conventional photometric cell and in the present invention, if b = 2a, the volume Vf is given by the following equation.
^{Vf = b 3/4 = 2a} 3 = 4 · (a 3/2) = 4V ............ (3)

  As is clear from the comparison between the formulas (2) and (3), the measurement container 2 of the first embodiment may have a liquid sample volume that is ¼ that of a conventional photometric cell. It can be greatly reduced. Moreover, as shown in FIG. 3, in the main body 3, the length a (= b / 2) of the reflecting portion 3b, which is the depth along the thickness direction of the concave portion forming the liquid holding portion 2a, is a conventional photometric cell. Therefore, the thickness of the main body 3 itself is reduced and the measurement container 2 is downsized.

  Further, when the light beam emitted from the light projecting optical system 6 is incident on each liquid holding unit 2a of the measurement container 2, the analysis optical device 1 reflects the incident light beam on the reflection units 3a and 3b, and then receives the light receiving optical system 7. Incident to the side. At this time, the incident position of the light beam incident on the liquid holding unit 2a changes, and the optical axis AL6 of the light beam emitted from the light projecting optical system 6 moves to the right as compared with FIG. 3, for example, as shown in FIG. It is assumed that the point where the extension line of the optical axis AL6 intersects the reflecting portion 3b has moved to the point P11 on the cover 4 side from the point P1. In this case, the optical path length L along the optical axis AL6 and the optical axis AL7 of the light beam incident on the liquid holding unit 2a is calculated in the same manner as in FIG. It is constant at about twice the length a. For this reason, the analysis optical apparatus 1 does not need to set the positioning accuracy of the measurement container 2 high. At this time, the point P12 is a point that is in a position symmetrical to the point P11 with respect to the reflecting portion 3a.

  The measurement container 2 can ensure the same optical path length as the conventional one, and can measure with high accuracy even if the volume of the liquid sample required for the measurement is ¼ that of the conventional photometric cell.

(Embodiment 2)
Next, Embodiment 2 according to the measurement container of the present invention will be described in detail with reference to the drawings. The measurement container of Embodiment 1 was provided with a plurality of triangular prism-shaped liquid holding portions 2a whose horizontal cross section is a right-angled isosceles triangle and whose equilateral side is the front side. On the other hand, the measurement container of Embodiment 2 includes a plurality of triangular prism-shaped liquid holding portions 2a whose horizontal cross section is a right-angled isosceles triangle and whose hypotenuse is the front side. FIG. 5 is a schematic configuration diagram showing a measurement container according to the second embodiment and an analysis optical device using the measurement container. FIG. 6 is a plan view showing the measurement container shown in FIG. 5 together with schematic configurations of the light projecting optical system and the light receiving optical system.

  Here, in the following description, the same components as those of the measurement container and the analysis optical device of Embodiment 1 are denoted by the same reference numerals.

  As shown in FIGS. 5 and 6, in the analysis optical device 10, the main body 3 of the measurement container 2 has a plurality of concave portions that serve as the liquid holding portion 2a. Each concave portion of the main body 3 has a triangular prism shape in which the horizontal cross section is a right-angled isosceles triangle and the equilateral side is the front side, and the two equilateral sides sandwiching the oblique side are the reflecting portions 3b. Further, the cover 4 is a reflecting portion in which a left half portion adjacent to the right half portion through which the light beam is transmitted is formed with a reflecting portion 4a that reflects light.

  Therefore, when the light beam emitted from the light projecting optical system 6 enters each liquid holding unit 2a of the measurement container 2, the analysis optical device 10 reflects the incident light beam on the reflection units 3b and 4a, and then receives the light receiving optical system 7. The information on the analysis result relating to the amount of light incident on the side and detected by the photodetector 74 is output to the arithmetic control unit 8. The concentration of the predetermined component in the liquid sample is determined based on the calculation result in the calculation control unit 8.

  At this time, as shown in FIG. 6, the measurement container 2 reflects the light beam incident on the liquid holding unit 2a five times at the reflection units 3b and 4a and reflects the 3 {= (5 + 1) / 2} th reflection unit. Arranged with respect to the light projecting optical system 6 so that an image of the light source is formed on 4a. Thereby, the light beam that has reached the reflecting portion 4 a is reflected by the reflecting portion 4 a, is then reflected again by the two reflecting portions 3 b, passes through the cover 4, and enters the light receiving optical system 7.

Further, the optical path length L along the optical axis AL6 and the optical axis AL7 in each liquid holding portion 2a is the length of the hypotenuse of the liquid holding portion 2a c, and the incident angle of the optical axis AL6 to the cover 4 of the measuring container 2 ( Assuming that the angle formed between the optical axis AL6 and the normal line of the cover 4 is θ, it is given by the following equation as in the first embodiment.
L = 2c / cosθ (∵cosθ = c / (L / 2)
≒ 2c …………………… (4)

Further, when the liquid level of the liquid sample injected into the liquid holding portion 2a and c / 2, the bottom area of the liquid holding portion 2a than c ^2/4, the volume V of liquid sample held in the liquid holding portion 2a Is given by:
^{V = c 2/4 · c} / 2 = c 3/8 ..................... (5)

On the other hand, a conventional photometric cell in which a light beam is incident from one side surface of a rectangular parallelepiped cell and is emitted from the other opposite side surface has a depth (= optical path) along the incident direction of the light beam with respect to the internal method. long) b, the width b / 2 perpendicular to the incident direction of the light beam, when the liquid level of the liquid sample to b / 2, the volume Vf of the liquid sample becomes b ^3/4. At this time, since the optical path length needs to be the same in the conventional photometric cell and the present invention, if b = 2c, the volume Vf is given by the following equation.
^{Vf = b 3/4 = 2c} 3 = 16 · (c 3/8) = 16V ............ (6)

  As is clear from the comparison between the formulas (5) and (6), the measurement container 2 of the second embodiment requires that the volume of the liquid sample is 1/16 that of a conventional photometric cell, and the liquid sample is It can be greatly reduced. Moreover, since the length of the hypotenuse of the liquid holding part 2a is c in the main body 3, the depth along the thickness direction of the liquid holding part 2a shown in FIG. Then, since it is 2c, the thickness of the main body 3 itself is reduced, and the measurement container 2 is downsized.

  The measurement container 2 of the second embodiment can ensure the same optical path length as the conventional one, and can measure with high accuracy even if the volume of the liquid sample required for the measurement is 1/16 that of the conventional photometric cell. Can do.

(Embodiment 3)
Next, a third embodiment of the analytical optical apparatus of the present invention will be described in detail with reference to the drawings. The analysis optical device according to the first embodiment includes a plurality of triangular prism-shaped liquid holding portions 2a. On the other hand, the analysis optical device according to Embodiment 3 includes a plurality of quadrangular prism-shaped liquid holding portions 2b. FIG. 7 is a schematic configuration diagram illustrating a measurement container according to the second embodiment and an analysis optical device using the measurement container. FIG. 8 is a plan view showing the measurement container shown in FIG. 7 together with schematic configurations of the light projecting optical system and the light receiving optical system. FIG. 9 is an enlarged view of a portion B in FIG.

  As shown in FIGS. 7 and 8, in the analysis optical device 20, the main body 3 of the measurement container 2 has a plurality of recesses that become the liquid holding portions 2b. Each concave portion of the main body 3 has a rectangular column shape in which the horizontal cross section is rectangular and the short side is the front side, and the three long sides sandwiched between the two long sides and the two long sides are a total of three sides. Reflecting portions 3c and 3d are formed.

  Therefore, when the light beam emitted from the light projecting optical system 6 is incident on each liquid holding unit 2b of the measurement container 2, the analysis optical device 20 reflects the incident light beam on the reflection units 3c and 3d, and then receives the light receiving optical system 7. The information on the analysis result relating to the amount of light incident on the side and detected by the photodetector 74 is output to the arithmetic control unit 8. The concentration of the predetermined component in the liquid sample is determined based on the calculation result in the calculation control unit 8.

  At this time, as shown in FIGS. 8 and 9, the measurement container 2 reflects the light beam incident on the liquid holding unit 2b three times at the reflection units 3c and 3d and reflects the 2 {= (3 + 1) / 2} th. It arrange | positions with respect to the light projection optical system 6 so that the image of a light source may form in the reflective part 3d to perform. As a result, the light beam that has reached the reflecting portion 3d is reflected by the reflecting portion 3d, then is reflected again by the reflecting portion 3c, passes through the cover 4, and enters the light receiving optical system 7.

Further, as shown in FIG. 9, the optical path length L along the optical axis AL6 and the optical axis AL7 in each liquid holding part 2b is the length of the reflecting part 3c formed by the long side of the liquid holding part 2b as d, Assuming that the incident angle of the optical axis AL6 to the cover 4 of the measurement container 2 (the angle formed by the optical axis AL6 and the normal line of the cover 4) is θ, the following equation is given as in the first embodiment.
L = ≈2d ......... (7)

Further, when the length of the reflection part 3d formed by the short side of the liquid holding part 2b is d / 2 and the liquid surface height of the liquid sample injected into the liquid holding part 2b is d / 2, the liquid holding part 2b bottom area than d ^2/2, the volume V of liquid sample held in the liquid holding portion 2b is given by the following equation.
^{V = d 2/2 · d} / 2 = d 3/4 ..................... (8)

On the other hand, a conventional photometric cell in which a light beam is incident from one side surface of a rectangular parallelepiped cell and is emitted from the other opposite side surface has a depth (= optical path) along the incident direction of the light beam with respect to the internal method. long) b, the width b / 2 perpendicular to the incident direction of the light beam, when the liquid level of the liquid sample to b / 2, the volume Vf of the liquid sample becomes b ^3/4. At this time, since the optical path length needs to be the same in the conventional photometric cell and in the present invention, assuming that b = 2d, the volume Vf is given by the following equation.
^{Vf = b 3/4 = 2d} 3 = 8 · (d 3/4) = 8V ............ (9)

  As is clear from the comparison between the formulas (8) and (9), the measurement container 2 of the third embodiment may have a liquid sample volume that is 1/8 that of a conventional photometric cell. It can be greatly reduced. Moreover, as shown in FIG. 9, the main body 3 has a depth d (= b / 2) along the thickness direction of the concave portion forming the liquid holding portion 2a, which is half that of the conventional photometric cell. The thickness of the main body 3 itself is reduced, and the measurement container 2 is downsized.

  The measurement container 2 can ensure the same optical path length as in the past, and can measure with high accuracy even if the volume of the liquid sample required for the measurement is as small as 1/8 that of the conventional photometric cell.

It is a schematic block diagram which shows the measurement container which concerns on Embodiment 1, and the analysis optical apparatus using this measurement container. It is a top view which shows the measurement container shown in FIG. 1 with the schematic structure of a light projection optical system and a light reception optical system. It is the A section enlarged view of FIG. It is explanatory drawing shown similarly to FIG. 3 when the incident position of the light beam which injects into a liquid holding part changes. It is a schematic block diagram which shows the measurement container which concerns on Embodiment 2, and the analysis optical apparatus using this measurement container. It is a top view which shows the measurement container shown in FIG. 5 with the schematic structure of a light projection optical system and a light reception optical system. It is a schematic block diagram which shows the measurement container which concerns on Embodiment 3, and the analysis optical apparatus using this measurement container. It is a top view which shows the measurement container shown in FIG. 7 with the schematic structure of a light projection optical system and a light reception optical system. It is the B section enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,10,20 Analysis optical apparatus 2 Measuring container 2a, 2b Liquid holding part 3 Main body 3a, 3b Reflecting part 3c, 3d Reflecting part 4 Cover 4a Reflecting part 6 Projection optical system 61 Light source 62 Condensing lens 63 Diaphragm 64 Projecting lens 7 Light receiving optical system 71 Relay lens 72 Slit 73 Concave diffraction grating 74 Optical detector AL6, AL7 Optical axis

Claims (5)

A measurement container that has a liquid holding part for holding a liquid sample and is used in an analysis optical device,
The liquid holding unit is disposed on the front surface of the measurement container, and includes a transmission unit that transmits a light beam, and a plurality of reflection units that reflect the light beam that is transmitted through the transmission unit and is incident and output from the transmission unit. A measuring container formed into a triangular prism shape.   The measuring container according to claim 1, wherein the transmissive portion is formed with a reflective portion that reflects light at a portion adjacent to a portion through which the light flux is transmitted.   The measurement container according to claim 1, wherein the liquid holding unit has a horizontal isosceles cross-sectional shape that is a right-angled isosceles triangle, and one side of the equilateral side is disposed in the transmission unit.   The measurement container according to claim 2, wherein the liquid holding part has a horizontal isosceles cross-sectional shape that is a right-angled isosceles triangle, and a hypotenuse is disposed in the transmission part. The transmission part and the plurality of reflection parts are arranged in a vertical direction,
The measurement container according to claim 1, wherein the liquid holding unit holds a constant optical path length of the light flux that passes through the held liquid sample.

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