JP6800508B1 - Liquid level measuring device, liquid level measuring system, and liquid level measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid amount measuring device or the like capable of measuring a liquid amount with high accuracy while suppressing a cost. SOLUTION: In a region where a well 101 is formed in a microplate 100, a light source 10 that emits infrared light toward a first surface 100a of the microplate 100 is arranged between the first surface 100a and the light source 10. A lens 11 that refracts infrared light to provide parallel light H that spreads over a region larger than the maximum width of the well 101 in the plane direction of the microplate 100, and a second surface of the microplate 100 that is opposite to the first surface 100a. A light detector 13 arranged on the 100b side to receive the parallel light H transmitted through the microplate 100, and a light diffusion arranged between the second surface 100b and the light detector 13 to diffuse the parallel light H. A member 12 and a calculation device 14 for calculating the amount of liquid of sample S in the well 101 from the amount of parallel light H received by the light detector 13 are provided. [Selection diagram] FIG. 2B

Description

The present invention relates to a liquid amount measuring device or the like for measuring a liquid amount.

Conventionally, an apparatus for measuring the amount of liquid sample dispensed into each well of a container such as a microplate is known. An example of such a device is described in Patent Document 1.

In the apparatus of Patent Document 1, a sample in the well is photographed by an infrared camera, and the amount of the sample in the well can be measured from the shade of the photographed image.

JP-A-2018-40705

However, when an infrared camera is used as the liquid amount measuring device, there is a problem that the cost of the device increases. In particular, in the apparatus described in Patent Document 1, since the entire microplate can be photographed at one time, the lens size becomes large, which further increases the cost.

Therefore, the present invention provides a liquid amount measuring device or the like capable of highly accurate liquid amount measurement while suppressing the cost.

The liquid amount measuring device according to one aspect of the present invention is a liquid amount measuring device for measuring the liquid amount of a liquid sample contained in a storage hole recessed from the upper surface to the lower surface in a container made of a material that transmits infrared light. In the region where the accommodation hole is formed, the light source that emits infrared rays toward one surface of the upper surface and the lower surface is arranged between the one surface and the light source. A lens that refracts infrared rays to provide measurement light that spreads over a region larger than the maximum width of the accommodation hole in the surface direction of the container, which is the direction in which the upper surface expands, and the upper surface and the lower surface of the container. A light detector arranged on the other surface side to receive the measurement light transmitted through the container and a light diffusion arranged between the other surface and the light detector to diffuse the measurement light. It includes a member and a calculation device that calculates the amount of liquid of the sample in the accommodating hole from the amount of light of the measurement light received by the light detector.

Further, in the liquid amount measuring device, a plurality of the accommodating holes are provided in the container at intervals in the plane direction, and the light source, the lens, the light diffusing member, and the photodetector are set as one set. It may be possible to arrange each of them toward each of the accommodation holes.

Further, in the liquid amount measuring device, the width dimension in the surface direction of the light diffusing member may be larger than the maximum width dimension in the surface direction of the accommodating hole.

Further, in the liquid amount measuring device, the distance between the light diffusing member and the photodetector may be 0.5 times or more the width dimension in the surface direction of the measured light.

Further, in the liquid amount measuring device, the distance between the light diffusing member and the other surface may be 10 mm or less.

Further, in the liquid amount measuring device, the width dimension of the light receiving range of the photodetector in the surface direction may be set to be equal to or less than the width dimension in the surface direction of the measurement light.

Further, in the liquid amount measuring device, the distance between the photodetector and the other surface may be 30 mm or less.

Further, the liquid amount measuring device is an annular member arranged between the lens and the one surface and at least one of the light diffusing member and the other surface, and is itself. An aperture diaphragm that defines the width of the measurement light by the inner peripheral edge may be further provided.

Further, the liquid amount measuring system according to one aspect of the present invention supports a set of the liquid amount measuring device, the light source, the lens, the light diffusing member, and the light detector in the liquid amount measuring device. It is provided with a moving device that moves relative to the container in the plane direction.

Further, in the liquid amount measuring system, the moving device is a set of a first moving portion for moving the container in the first direction in the plane direction, the light source, the lens, the light diffusing member, and the photodetector. May have a second moving portion that moves the light in the second direction in the plane direction intersecting the first direction.

Further, in the liquid amount measuring system, only one set of the light source, the lens, the light diffusing member, and the photodetector is provided, and the moving device sets the set in a plurality of the accommodating holes. They may be arranged one by one.

Further, in the liquid amount measuring system, a plurality of the accommodating holes are provided in the container at equal intervals in the first direction in the surface direction and the second direction in the surface direction intersecting the first direction. A plurality of sets of the light source, the lens, the light diffusing member, and the light detector are provided side by side in the first direction, and the moving device arranges the plurality of sets arranged in the first direction in the second direction. You may move it to.

Further, the liquid amount measuring method according to one aspect of the present invention is a liquid amount measuring method for measuring the liquid amount of a liquid sample contained in a storage hole recessed from the upper surface to the lower surface in a container made of a material that transmits infrared rays. The step of radiating infrared rays toward one of the upper surface and the lower surface in the region where the accommodation hole is formed, and the direction in which the upper surface is expanded by refracting the infrared rays. The step of incidenting the measurement light on the container as the measurement light spreading in a region larger than the maximum width dimension of the accommodation hole in the surface direction of the container, the step of diffusing the measurement light transmitted through the container, and the diffused measurement light. It includes a step of receiving light and a step of calculating the amount of liquid of the liquid sample in the accommodating hole from the amount of light of the measured light received.

According to the above-mentioned liquid amount measuring device or the like, it is possible to measure the liquid amount with high accuracy while suppressing the cost.

It is a front view of the liquid amount measuring system which concerns on embodiment of this invention. It is a front view of the liquid amount measuring apparatus in the said liquid amount measuring system, and is the figure which shows the state of the liquid amount measurement when a sample exists at the bottom of a well. It is a front view of the liquid amount measuring apparatus in the said liquid amount measuring system, and is the figure which shows the state of the liquid amount measurement when the sample exists at the offset position in the well. It is a graph of the experimental result which shows an example of the conversion table stored in the arithmetic unit of the liquid amount measurement system. It is a graph of the experimental result when the light diffusing member is not provided. It is a perspective view of the liquid amount measurement system which concerns on the 1st modification. It is a perspective view of the liquid amount measurement system which concerns on the 2nd modification. It is a perspective view of the liquid amount measurement system which concerns on 3rd modification. It is a front view of the liquid amount measuring apparatus in the liquid amount measuring system which concerns on 4th modification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(overall structure)
As shown in FIG. 1, the liquid amount measuring system 1 of the present embodiment includes, for example, a liquid amount measuring device 2 for measuring the liquid amount of the liquid sample S in the well 101 of the microplate 100 as a container, and a liquid amount measuring device. A moving device 3 for moving 2 relative to the microplate 100 is provided.

Here, the microplate 100 is made of a material capable of transmitting infrared rays, which will be described later, and has a plate shape, and has a first surface (lower surface) 100a and a second surface (upper surface) 100b arranged in parallel. ing. A plurality of wells 101 extending from the second surface 100b to the middle position in the plate thickness direction are formed so as to be recessed in the thickness direction of the microplate 100 (hereinafter, plate thickness direction) toward the first surface 100a. All wells 101 have the same shape. Further, the plurality of wells 101 are arranged in the plane direction of the microplate 100 (hereinafter referred to as the plate plane direction), that is, in the horizontal direction at equal intervals. More specifically, a plurality of wells 101 are regularly arranged in the X direction (first direction) in the plate surface direction and in the Y direction orthogonal to (intersecting) the X direction.

Liquid samples S used for various analyzes, inspections, tests, etc. are dispensed and stored in each well 101. In this embodiment, the sample S contained in the well 101 is an aqueous solution. It is known that the peak wavelength of the absorption spectrum of water is about 1450 [nm].

Here, the shape, size, and quantity of the well 101 are not particularly limited. Specifically, 24, 96, 384 and the like are exemplified as the quantity of the well 101. Further, the shape of the bottom of the well 101 may be a flat bottom shape, a U shape, or a V shape.

(Liquid volume measuring device)
As shown in FIGS. 2A and 2B, the liquid amount measuring device 2 includes a light source 10 that emits infrared rays, a lens 11 that bends infrared rays from the light source 10 and causes them to enter the microplate 100, and infrared rays transmitted through the microplate 100. A light diffusing member 12 that diffuses the light, a light detector 13 that receives infrared rays that have passed through the light diffusing member 12, and a calculation device 14 that calculates the amount of liquid of sample S in the well 101 from the amount of light received by the light detector 13. And have.

(light source)
The light source 10 is, for example, a near-infrared LED in which the peak wavelength of the emission spectrum is set to 1450 [nm] in the present embodiment. That is, the light source 10 is a point light source that emits near infrared rays. As shown in FIGS. 2A and 2B, the light source 10 is arranged below the first surface 100a of the microplate 100 and radiates near infrared rays toward the first surface 100a in the plate thickness direction. When measuring the liquid volume of the sample S, the center of the light source 10 is located on the center line CL of the well 101 to be measured. Hereinafter, the position of the light source 10 at the time of measuring the amount of liquid is defined as the measurement position.

(lens)
The lens 11 is a plano-convex lens, and is arranged between the first surface 100a and the light source 10 with the flat side facing the light source 10 side and the convex side facing the first surface 100a side of the microplate 100. .. The lens 11 has a plate shape that extends in the direction of the plate surface. At the measurement position, the position of the center of the lens 11 coincides with the position of the center of the light source 10. Therefore, the center of the lens 11 is located on the center line CL of the well 101.

The width dimension of the lens 11 in the plate surface direction is slightly larger than the maximum width dimension (diameter of the well 101) of the well 101 to be measured. As a result, the lens 11 spreads the infrared rays radiated from the light source 10 over a region larger than the width dimension of the well 101, which is parallel light H (within a circular cross section, the traveling direction of the light is substantially parallel to the center line CL). Light)) is converted into light and is incident on the first surface 100a of the microplate 100. At the measurement position, the parallel light H passes only through the well 101 (101A) to be measured. That is, the width dimension of the lens 11 is larger than the maximum width dimension W of the well 101 and the well 101 is prevented from incident parallel light H on the well 101 (101B) adjacent to the well 101 (101A) to be measured. The size of the lens 11 is determined so as to be smaller than the value obtained by adding twice the gap G between the wells 101 to the maximum width dimension W of the lens 11.

The distance between the convex surface of the lens 11 and the first surface 100a (distance in the plate thickness direction) is preferably 10 [mm] or less.

(Photodetector)
For the photodetector 13, for example, an InGaAs photodiode is adopted in this embodiment. The photodetector 13 has high light receiving sensitivity with respect to near infrared rays having a wavelength of 1000 [nm] or more and 1700 [nm] or less as infrared rays. The photodetector 13 is arranged on the second surface 100b side of the microplate 100, receives parallel light H transmitted through the microplate 100, and generates a signal (for example, voltage or current) according to the intensity of the received light. To do. The type of the photodiode is not particularly limited, but a PIN type or an APD type is preferable. At the measurement position, the center of the photodetector 13 is arranged on the center line CL of the well 101. Further, instead of the photodiode, the photodetector 13 may use a photoelectric conductive element or the like whose electrical resistance changes depending on the amount of received light. Here, the distance between the photodetector 13 and the second surface 100b of the microplate 100 (distance in the plate thickness direction) is preferably 30 [mm] or less. Further, the width dimension of the light receiving range of the photodetector 13 in the plate surface direction is set to be equal to or less than the width dimension in the plate surface direction in the parallel light H.

(Light diffusion member)
The light diffusing member 12 is a plate-shaped diffusing plate that spreads in the plate surface direction of the microplate 100. The light diffusing member 12 is, for example, a circular resin plate containing light diffusing fine particles inside or on the surface. The light diffusing member 12 may be frosted glass.

The light diffusing member 12 is arranged between the second surface 100b of the microplate 100 and the photodetector 13. The light diffusing member 12 diffuses the parallel light H transmitted through the microplate 100 in various directions inside itself. As a result, the brightness distribution on the surface of the light diffusing member 12 on the photodetector 13 side is averaged in the plate surface direction. Here, the concept of "averaging" includes not only the case where the luminance distribution is completely averaged but also the case where the luminance distribution is smoothed by the light diffusing member 12.

The width dimension of the light diffusing member 12 in the plate surface direction (diameter of the light diffusing member 12) is larger than the maximum width dimension of the well 101 (diameter of the well 101) and is equal to or equal to the width dimension of the parallel light H in the plate surface direction. It is preferably more than that. Further, the distance in the plate thickness direction between the light diffusing member 12 and the photodetector 13 is preferably 0.5 times or more the width dimension in the plate surface direction in the parallel light H.
(Arithmetic logic unit)
The computing device 14 determines the amount of liquid of the sample S in the well 101 to be measured from the signal value (voltage value or current value) generated by the photodetector 13 according to the intensity of the parallel light H received by the photodetector 13. Is calculated. The arithmetic unit 14 has a computer including a CPU, RAM, ROM, etc. (not shown). The arithmetic unit 14 stores in advance a table or the like showing the relationship between the liquid amount of the sample S in the well 101 and the signal value generated by the photodetector 13. The arithmetic unit 14 calculates the amount of liquid in the sample S based on this table. Specifically, for example, assuming that the amount of light (signal value) when the liquid volume of sample S is 0 μliter is 100%, a conversion table (calculation formula or calculation table) as shown in FIG. 3A may be used. Good) is included in the arithmetic unit 14.

(Mobile device)
Next, the moving device 3 will be described. The structure of the mobile device 3 is not particularly limited to the following structure. Returning to FIG. 1, the moving device 3 of the present embodiment has a transfer table (first moving unit) 15 for moving the microplate 100 only in the X direction in the plate surface direction, and a liquid amount measuring device 2 for the transfer table 15. It has a horizontal drive unit (second moving unit) 16 that moves the set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 in the plate surface direction only in the Y direction. Here, in the present embodiment, the plate surface directions coincide with the horizontal direction.

The transport table 15 is, for example, a belt conveyor extending in the X direction. A microplate 100 is placed on the upper surface of the transport table 15. For example, the transport device 200 in the dispensing device (not shown) is arranged on the upstream side of the transport table 15 in the X direction, and the transport device 300 in the analyzer (not shown) is arranged on the downstream side in the X direction of the transport table 15. ing. The microplate 100 is delivered from the transfer device 200 in the dispensing device to the transfer table 15, and after the liquid amount of the sample S is measured by the liquid amount measuring device 2, it is delivered to the transfer device 300 in the analyzer. It has become. The transport table 15 can also reciprocate the microplate 100 on both sides in the X direction.

The horizontal drive unit 16 has a motor and a power transmission mechanism (belt, gear, etc.). Further, the horizontal drive unit 16 supports a set of a light source 10, a lens 11, a light diffusing member 12, and a photodetector 13. The horizontal drive unit 16 is provided with a control device 17. The control device 17 has a calculator including a CPU, RAM, ROM, etc. (not shown). The control device 17 stores in advance the movement paths of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13. Examples of the movement path include a zigzag-shaped path that goes in one direction in the Y direction and then goes in the other direction in the Y method. The control device 17 sets the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 in the Y direction along this movement path and in synchronization with the movement of the transport table 15 in accordance with the operation of the transport table 15. And sequentially arrange toward each well 101. Therefore, a set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 is sequentially arranged toward each well 101 one by one, and the light source 10, the lens 11, the light diffusing member 12, and the photodetector are sequentially arranged. The liquid amount is measured on a one-to-one basis between the set of the vessel 13 and each well 101. The control device 17 may also control the transport table 15 together with the horizontal drive unit 16.

(Action effect)
In the liquid amount measuring system 1 of the present embodiment described above, as shown in FIG. 2A, a part of the infrared rays emitted from the light source 10 is absorbed by the sample S in the well 101. Since the amount of infrared rays absorbed increases as the amount of the sample S in the well 101 increases, the amount of light received by the photodetector 13 decreases as the amount of the sample S in the well 101 increases. Then, the liquid amount of the sample S can be calculated by the arithmetic unit 14 by using the table of FIG. 3A according to the amount of the parallel light H received by the photodetector 13. By using the light source 10 and the photodetector 13 for the measurement in this way, it is possible to measure the liquid amount of the sample S with high accuracy while suppressing the cost with a very simple structure.

Here, as shown in FIG. 2B, the sample S may be housed in the well 101 not only at the bottom of the well 101 but also at various positions offset from the inner wall surface and the bottom surface of the well 101. .. Even in such a case, in the liquid volume measuring system 1 of the present embodiment, infrared rays (parallel light H) can be incident on the entire well 101 in each well 101, so that the liquid amount measuring system 1 can be applied to any position in the well 101. Even if the sample S is present, infrared rays can be absorbed according to the liquid amount of the sample S, and the liquid amount of the sample S can be easily obtained without pretreatment such as diluting or bulking the sample S. Measurement becomes possible. That is, since the measurement can be performed not by the transmitted image of the parallel light H passing through the sample S but by the amount of transmitted light of the parallel light H, it is possible to flexibly deal with the deviation of the sample S and the like.

Further, since the liquid amount is measured using infrared rays instead of visible light, pretreatment such as coloring of sample S is not required as in a generally known plate reader, and a device such as an optical filter is not required. .. Further, since the photodetector 13 of the present embodiment has low (or no) light receiving sensitivity to visible light, it is possible to avoid disturbance to the measured value due to the incident of visible light from the outside during measurement.

Further, by converting the infrared rays from the light source 10 into parallel light H by the lens 11, even if the light source 10 is diffused light from a point light source sufficiently small with respect to the maximum width dimension of the well 101, the entire well 101 Infrared rays can be incident on the lens, and the measurement accuracy can be improved.

Further, a light diffusing member 12 is provided between the photodetector 13 and the microplate 100, and the brightness of the light is averaged (smoothed / leveled) in the plate surface direction to reduce the amount of light received by the photodetector 13. It suppresses the occurrence of errors and leads to improvement in measurement accuracy. If the light diffusing member 12 is not provided, the measurement accuracy will vary as shown in FIG. 3B.

Here, in the present embodiment, as described above, the width dimension of the light receiving range of the photodetector 13 in the plate surface direction is set to be equal to or less than the width dimension in the plate surface direction in the parallel light H, so that the light is transmitted through the microplate 100. Not all of the parallel light H, but a part of the parallel light H transmitted through the microplate 100 may be received by the photodetector 13. However, since the brightness distribution in the plate surface direction is averaged by providing the light diffusing member 12, the measurement accuracy can be ensured regardless of the size of the light receiving area of the photodetector 13.

Further, the moving device 3 moves the set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 in the X direction and the Y direction with respect to the microplate 100, and sequentially one by one in the well 101 to be measured. It can be arranged. Therefore, the liquid volume of the sample S in all the wells 101 can be sequentially and automatically measured.

Further, since the width dimension of the light diffusing member 12 is larger than the maximum width dimension of the well 101, the light diffusing member 12 can be passed through all of the parallel light H passing through the well 101. Therefore, all of the parallel light H that has passed through the well 101 can be averaged and incident on the photodetector 13, and even if the sample S is offset in the well 101, the liquid amount of the sample S and the light received by the photodetector 13 are received. It suppresses the occurrence of an error in the proportional relationship of the quantity, which leads to improvement in measurement accuracy.

Further, by increasing the distance between the light diffusing member 12 and the photodetector 13 and preferably setting this distance to 0.5 times or more the width dimension of the parallel light H, the light diffusing member 12 causes completely diffused light (brightness is in the direction). The parallel light H, which is in a constant state regardless of the above, can be received by the photodetector 13 at a more averaged position, which leads to an improvement in measurement accuracy.

Further, by making the distance between the light diffusing member 12 and the micro plate 100 close, preferably this distance is 10 [mm] or less, the parallel light H transmitted through the micro plate 100 increases in the direction away from the light diffusing member 12. The light diffusing member 12 can be passed before the light is diffused, the amount of light passing through the light diffusing member 12 can be secured, the amount of light received by the photodetector 13 can be secured, and the measurement accuracy is improved.

Further, by making the distance between the photodetector 13 and the microplate 100 close, preferably the distance between the photodetector 13 and the second surface 100b of the microplate 100 is 30 [mm] or less, the photodetector 13 can be used. It is possible to prevent external light from entering as noise and to make the entire device compact.

Further, since the measurement is performed by operating the microplate 100 in the X direction by the moving device 3, the liquid amount measuring system 1 of the present embodiment can be easily used for the dispensing device (not shown) holding the microplate 100. It can be additionally installed in, and the function of measuring the amount of liquid can be easily added to the existing dispensing device.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.
For example, contrary to the above case, the light diffusing member 12 and the photodetector 13 may be arranged on the first surface 100a side of the microplate 100, and the light source 10 and the lens 11 may be arranged on the second surface 100b side.

Further, the peak wavelength of the emission spectrum of the light source 10 is not limited to the above case, and can be appropriately set according to the difference in the sample S. For example, when the sample S is an ethanol solution, it is preferable to use a light source having a peak wavelength of 1650 [nm] in the emission spectrum.

Further, the light source 10 is not limited to the case of an infrared LED, and may be, for example, an infrared light bulb. Further, the light source 10 is not limited to a point light source, and may be a surface light source that emits parallel light H. In this case, the samples S in the plurality of wells 101 can be irradiated with infrared rays at once. However, in this case, the measurement accuracy may be lower than in the case of irradiating infrared rays for each well 101. However, it is possible to secure the necessary and sufficient measurement accuracy by correcting the data with the arithmetic unit 14.

Further, the microplate 100 may be calibrated before the liquid amount measurement is performed. That is, for example, by injecting infrared rays into the well 101 in an empty state where the sample S is not contained in the well 101 of the microplate 100 and measuring the light amount, the reference light amount when the liquid amount is 0 μliter is stored in the memory. You may. As a result, a correction value based on individual differences for each microplate 100 can be obtained, and by inputting this correction value into the arithmetic unit 14 in advance, the accuracy of actual sample S liquid volume measurement is improved. can do. Further, for example, with respect to the liquid culture (water or ethanol in this case) to be measured, a plurality of correctly measured specified amounts (for example, 0 μl, 20 μl, 40 μl) are stored in the well 101 of the microplate 100. By injecting infrared rays into the well 101 and measuring the amount of light, a reference amount of light corresponding to a plurality of specified liquid amounts may be stored in the memory. With the reference light amount corresponding to these plurality of specified liquid amounts, it is possible to obtain a correction value regarding the correlation between the light amount and the liquid amount for each microplate 100, and further, the accuracy in the actual liquid amount measurement of the sample S. Can be improved.

Further, the moving device 3 may move the microplate 100 in the Y direction by the transfer table 15 and move the liquid amount measuring device 2 in the X direction.

[First modification]
Further, the liquid amount measuring device 2 may be moved to measure the liquid amount while the position of the microplate 100 is fixed. Specifically, as shown in FIG. 4, the moving device 3A moves the arm 22 in the X direction with respect to the support column 20 and the support base 21, the pair of arms 22 supported by the support column 20, and the support column 20. It has a first horizontal drive unit 23 for causing the support column to move, a second horizontal drive unit 24 for moving the support pillar together with the arm 22 in the Y direction, and a control device 25 for controlling the operation of these two drive units 23 and 24. May be good.

The support column 20 extends in the Z direction (vertical direction) orthogonal (intersecting) in the X direction and the Y direction.
The support base 21 supports the lower part of the support pillar 20. The support base 21 is provided with, for example, a guide groove (or slide rail) 21a, and supports the support pillar 20 so as to be slidable in the Y direction.
The pair of arms 22 are supported by the support columns 20 and extend in the X direction. The arms 22 are arranged apart from each other in the Z direction and face each other in the Z direction.

The lower arm 22 (22A) is provided with one light source 10 and one lens 11 so as to project upward in the Z direction. Further, the upper arm 22 (22B) is provided with one photodetector 13 and one light diffusing member 12 so as to project downward in the Z direction. That is, in this embodiment, only one set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 is provided. The arm 22 can be moved relative to the support column 20 in the X direction by, for example, a guide rail (not shown) provided on the support column 20. The microplate 100 can be arranged so as to be sandwiched in the Z direction by a pair of arms 22.

Although not shown in detail, the first horizontal drive unit 23 has a motor and a power transmission mechanism (belt, gear, etc.). The first horizontal drive unit 23 is provided on the support column 20, and the pair of arms 22 are synchronized and slid with respect to the support column 20 in the X direction.

The second horizontal drive unit 24 has a motor and a power transmission mechanism (belt, gear, etc.), although detailed illustration is omitted. The second horizontal drive unit 24 is provided on the support base 21, and together with the support pillar 20, the pair of arms 22 can be slid along the guide groove 21a with respect to the support base 21 in the Y direction.

The control device 25 controls the operations of the first horizontal drive unit 23 and the second horizontal drive unit 24. The control device 25 has a calculator including a CPU, RAM, ROM, etc. (not shown). The control device 25 stores in advance the movement path K of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13. The first horizontal drive unit 23 and the second horizontal drive unit 24 are operated to move the arm 22 according to the movement path K.

In the present embodiment, the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 are moved to one side in the X direction, then moved to one side in the Y direction, and then moved to the other side in the X direction again. By repeating this operation, a set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 is moved in a zigzag manner and sequentially arranged toward each well 101. Therefore, a set of the light source 10, the lens 11, the light diffusing member 12, and the photodetector 13 is sequentially arranged toward each well 101 one by one, and the light source 10, the lens 11, the light diffusing member 12, and the photodetector are sequentially arranged. The liquid amount is measured on a one-to-one basis between the set of the vessel 13 and each well 101. Here, the control device 25 may be provided integrally with the arithmetic unit 14, or may be a separate body.

[Second modification]
Further, as shown in FIG. 5, the moving device 30 moves the arm 22 in the X direction (horizontal direction) together with the support column 20, the support base 21, the pair of arms 22 fixedly supported by the support column 20, and the support column 20. It may have a horizontal drive unit 33 to be operated and a control device 25 for controlling the horizontal drive unit 33.

The pair of arms 22 extend in the Y direction from the support column 20.
A plurality of sets of the light source 10 and the lens 11 are provided on the lower arm 22 (22A) so as to project upward in the Z direction, arranged side by side at equal intervals in the Y direction. The spacing and quantity of the set of the light source 10 and the lens 11 in the Y direction correspond to the spacing and quantity of the wells 101 in the Y direction. That is, it is possible to arrange the set of the light source 10 and the lens 11 so as to correspond to each of the wells 101. The light source 10 and the lens 11 may be provided on separate arms.

Further, the upper arm 22 (22B) is provided with a plurality of sets of the photodetector 13 and the light diffusing member 12 so as to project downward in the Z direction, arranged side by side at equal intervals in the Y direction. The spacing and quantity of the set of the photodetector 13 and the light diffusing member 12 in the Y direction correspond to the spacing and quantity of the wells 101 in the Y direction. That is, it is possible to arrange the set of the photodetector 13 and the light diffusing member 12 corresponding to each of the wells 101. The photodetector 13 and the light diffusing member 12 may be provided on separate arms.

In the case of having such a configuration, the liquid amount can be sequentially measured for each row of the wells 101 by moving the pair of arms 22 to one of the X directions by the horizontal drive unit 33. Therefore, since it is possible to finish the liquid amount measurement in the wells 101 arranged in the Y direction at once, the liquid amount measurement can be completed in a short time.

In the moving device 30 of the second modification, the microplate 100 may be moved in the X direction by the above-mentioned transport table 15.

[Third modification example]
Further, as shown in FIG. 6, the moving device 40 moves the arm 22 in the Y direction (horizontal direction) together with the support column 20 and the support base 21, the pair of arms 22 fixedly supported by the support column 20, and the support column 20. It may have a horizontal drive unit 43 to be operated and a control device 25 to control the horizontal drive unit 43.

The pair of arms 22 extend in the X direction from the support column 20.
A plurality of sets of the light source 10 and the lens 11 are provided on the lower arm 22 (22A) so as to project upward in the Z direction, arranged side by side at equal intervals in the X direction. The spacing and quantity of the set of the light source 10 and the lens 11 in the X direction correspond to the spacing and quantity of the wells 101 in the X direction. That is, it is possible to arrange the set of the light source 10 and the lens 11 so as to correspond to each of the wells 101.

Further, on the upper arm 22 (22B), a plurality of sets of the photodetector 13 and the light diffusing member 12 are provided side by side at equal intervals in the X direction so as to project downward in the Z direction. The spacing and quantity of the set of the photodetector 13 and the light diffusing member 12 in the X direction correspond to the spacing and quantity of the wells 101 in the X direction. That is, it is possible to arrange the set of the photodetector 13 and the light diffusing member 12 corresponding to each of the wells 101.

In the case of having such a configuration, the liquid amount can be sequentially measured for each row of the wells 101 by moving the pair of arms 22 to one of the Y directions by the horizontal drive unit 43. Therefore, since it is possible to finish the liquid amount measurement in the wells 101 arranged in the X direction at once, the liquid amount measurement can be completed in a short time.

In the moving device 40 of the third modification, the microplate 100 may be moved in the Y direction by the above-mentioned transport table 15.

[Fourth modification]
Further, as shown in FIG. 7, the liquid amount measuring device 2 may further include an opening throttle 50 which is an annular member. The aperture diaphragm 50 can be provided between the lens 11 and the first surface 100a of the microplate 100, and between the light diffusing member 12 and the second surface 100b of the microplate 100, respectively. The aperture diaphragm 50 is, for example, black and has a metal plate shape that does not transmit infrared rays (near infrared light), and has a guide hole penetrating in the plate thickness direction. The inner diameter of the guide hole of the aperture diaphragm 50 on the lens 11 side coincides with the width dimension of the parallel light H passing through the lens 11 in the plate surface direction, or is smaller than the width dimension of the parallel light H. The inner surface of the guide hole is a light absorbing surface 50a, and when light having an angle with respect to the center line CL arrives at the light absorbing surface 50a, the light is absorbed. As a result, the degree of parallelism of the parallel light H that has passed through the aperture diaphragm 50 becomes good. By providing such an aperture diaphragm 50, the width of the parallel light H is defined by the inner peripheral edge of the aperture diaphragm 50, and the parallel light H of the adjacent wells 101 is less likely to interfere with each other, so that the photodetector 13 can be used. It is possible to improve the accuracy of the liquid amount measurement based on the received light amount. The aperture diaphragm 50 may be provided only between the lens 11 and the first surface 100a and between the light diffusing member 12 and the second surface 100b.

According to the liquid amount measuring device or the like of the present invention, it is possible to measure the liquid amount with high accuracy while suppressing the cost.

1 Liquid amount measuring system 2 Liquid amount measuring device 3, 3A, 30, 40 Moving device 10 Light source 11 Lens 12 Light diffusing member 13 Light detector 14 Computing device 25 Control device 33 Horizontal drive unit 43 Horizontal drive unit 50 Aperture diaphragm 50a Light Absorption surface 100 Microplate 100a First surface 100b Second surface 101 Well H Parallel light (measurement light)
S (liquid) sample

Claims (13)

A liquid amount measuring device for measuring the amount of liquid sample contained in a storage hole recessed from the upper surface to the lower surface in a container made of a material that transmits infrared rays.
A light source that radiates infrared rays toward one of the upper surface and the lower surface in the region where the accommodation hole is formed.
Measurement light that is arranged between the one surface and the light source, refracts the infrared rays, and spreads over a region larger than the maximum width dimension of the accommodating hole in the surface direction of the container, which is the direction in which the upper surface expands. With the lens
A photodetector arranged on the upper surface side of the container and the other surface side of the lower surface to receive the measurement light transmitted through the container.
A light diffusing member arranged between the other surface and the photodetector to diffuse the measurement light,
An arithmetic unit that calculates the amount of liquid in the sample in the accommodation hole from the amount of light received by the photodetector.
A liquid volume measuring device including. A plurality of the accommodating holes are provided in the container at intervals in the surface direction.
The liquid amount measuring device according to claim 1, wherein a set of the light source, the lens, the light diffusing member, and the photodetector can be arranged one by one toward each of the accommodating holes. The liquid amount measuring device according to claim 1 or 2, wherein the width dimension in the plane direction of the light diffusing member is larger than the maximum width dimension in the plane direction in the accommodation hole. The liquid amount measuring device according to any one of claims 1 to 3, wherein the distance between the light diffusing member and the photodetector is 0.5 times or more the width dimension in the plane direction in the measured light. The liquid amount measuring device according to any one of claims 1 to 4, wherein the distance between the light diffusing member and the other surface is 10 mm or less. The liquid amount measuring device according to any one of claims 1 to 5, wherein the width dimension of the light receiving range of the photodetector in the plane direction is set to be equal to or less than the width dimension in the plane direction in the measurement light. The liquid amount measuring device according to any one of claims 1 to 6, wherein the distance between the photodetector and the other surface is 30 mm or less. An annular member arranged between the lens and one surface and at least one of the light diffusing member and the other surface, and by its own inner peripheral edge, the measurement light is measured. The liquid amount measuring device according to any one of claims 1 to 7, further comprising an opening diaphragm for defining a width. The liquid amount measuring device according to any one of claims 1 to 8.
A moving device that supports a set of the light source, the lens, the light diffusing member, and the photodetector in the liquid amount measuring device and moves them relative to the container in the plane direction.
Liquid volume measurement system equipped with. The moving device is
A first moving portion that moves the container in the first direction in the plane direction,
A second moving unit that moves the set of the light source, the lens, the light diffusing member, and the photodetector in the second direction in the plane direction intersecting the first direction.
The liquid amount measuring system according to claim 9. Only one set of the light source, the lens, the light diffusing member, and the photodetector is provided.
The liquid amount measuring system according to claim 9 or 10, wherein the moving device sequentially arranges the set in a plurality of the accommodating holes one by one. A plurality of the accommodating holes are provided in the container at equal intervals in the first direction in the surface direction and the second direction in the surface direction intersecting the first direction.
A plurality of sets of the light source, the lens, the light diffusing member, and the photodetector are provided side by side in the first direction.
The liquid amount measuring system according to claim 9 or 10, wherein the moving device moves a plurality of the sets arranged in the first direction in the second direction. A liquid volume measuring method for measuring the liquid volume of a liquid sample contained in a storage hole recessed from the upper surface to the lower surface in a container made of a material that transmits infrared rays.
A step of radiating infrared rays toward one of the upper surface and the lower surface in the region where the accommodating hole is formed.
A step of refracting the infrared rays and causing them to enter the container as measurement light spreading in a region larger than the maximum width dimension of the accommodation hole in the surface direction of the container, which is the direction in which the upper surface expands .
The step of diffusing the measurement light transmitted through the container and
The process of receiving the diffused measurement light and
A step of calculating the liquid amount of the liquid sample in the accommodating hole from the light amount of the measured light received, and
Liquid volume measuring method including.

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