Light source and automatic analyzer

Abstract

The purpose of the present invention is to provide an automatic analysis device and a light source that covers a wide wavelength range used by the automatic analysis device and produces a stable amount of light. A light source according to this invention comprises a substrate, a first LED that is provided on the substrate, and a fluorescent body that converts excitation light from the first LED into broadband light. A temperature sensor is embedded in the fluorescent body together with the first LED. Further, an automatic analysis device according to this invention comprises an absorbance measurement unit having the light source and a reaction disk having mounted thereon a reaction vessel accommodating a reaction liquid to be measured by the absorbance measurement unit.

Description

[Technical field]

[0001] The present invention relates to a light source and an automatic analyzer using the light source. [Background technology]

[0002] In an automatic analyzer for analyzing the amount of components contained in a biological sample such as blood or urine, the sample and reagent are dispensed into a liquid container, and the test item is generally analyzed based on the change in optical properties such as light absorption. In the absorbance analysis by an automatic analyzer, light from a light source is irradiated onto the sample or a reaction liquid in which the sample and reagent are mixed, the amount of transmitted light at a single or multiple measurement wavelengths that passes through the sample or reaction liquid is measured by a light receiving element to calculate the absorbance, and the amount of the component is determined from the relationship between the absorbance and the concentration.

[0003] Xenon lamps and halogen lamps have traditionally been used as light sources for absorption spectrometry, but the time it takes for the light intensity to stabilize is relatively long, about 30 minutes, and their lifespan is relatively short, so the automatic analyzer requires frequent maintenance. For this reason, in recent years, light emitting diodes (LEDs), which are expected to have a long lifespan, have been considered as light sources for absorption spectrometry.

[0004] However, the automated analyzer uses different reagents and light wavelengths depending on the components to be measured, and the wavelength range is as wide as 340 nm to 800 nm. Therefore, it is difficult to cover the entire wavelength band with one LED light, so it is possible to use multiple LED elements or a phosphor that converts the LED excitation light into broadband light. As an example of a light source using a phosphor, for example, Patent Document 1 discloses a broadband light source device that includes a first LED chip that emits a light beam in a first wavelength band, a phosphor provided on the light beam of the first LED chip, and a second LED chip that emits a light beam in a second wavelength band. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-87974 A Summary of the Invention [Problem to be solved by the invention]

[0006] Here, in order to realize the light intensity stability required for the absorption analysis of an automatic analyzer with an LED light source, it is important to suppress the self-heating of the LED when it is turned on and the change in light intensity due to the environmental temperature. However, in a light source using a phosphor as disclosed in Patent Document 1, although it is easy to control the temperature of the LED chip itself to a relatively stable temperature, it is difficult to control the temperature of the phosphor around it. When the temperature of the phosphor changes, the amount of light emitted from the phosphor also changes, so it is not easy to stabilize the overall light intensity over a wide wavelength band used in an automatic analyzer.

[0007] An object of the present invention is to provide a light source and an automatic analyzer that can cover a wide range of wavelength bands used in the automatic analyzer and have a stabilized light intensity. [Means for solving the problem]

[0008] In order to achieve the above object, the light source of the present invention comprises a substrate, a first LED provided on the substrate, and a phosphor that converts excitation light of the first LED into broadband light, and a temperature sensor is embedded in the phosphor together with the first LED. Effect of the Invention

[0009] According to the present invention, it is possible to provide a light source and an automatic analyzer that can stabilize the amount of light while covering a wide range of wavelength bands used in the automatic analyzer. Problems, configurations, and effects other than those described above will be made clear in the description of the following embodiments. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the overall configuration of an automatic analyzer. [Diagram 2] FIG. 2 is a diagram showing the configuration of an absorbance measuring unit that performs absorbance analysis in an automatic analyzer. [Diagram 3] FIG. 2 is a cross-sectional view showing the configuration of a light source according to the first embodiment. [Figure 4] FIG. 4 is a plan view showing an example of an arrangement of temperature sensors. [Diagram 5] FIG. 11 is a plan view showing the arrangement of temperature sensors in a light source of a comparative example. [Figure 6] This table shows the results of measuring the time it takes for the light intensity drift to stabilize after the LED is turned on. [Figure 7] 5 is a flowchart showing an example of a procedure for stabilizing the amount of light in the light source according to the first embodiment. [Figure 8] FIG. 11 is a cross-sectional view showing the configuration of a light source according to a second embodiment. [Figure 9] 10 is a flowchart showing an example of a procedure for stabilizing the amount of light in a light source according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] 1 is a schematic diagram showing the overall configuration of an automatic analyzer. The automatic analyzer according to this embodiment is composed of three types of disks, a sample disk 103, a reagent disk 106, and a reaction disk 109, a dispensing mechanism for moving samples and reagents between these disks, a control circuit 201 for controlling them, a light quantity measuring circuit 202 for measuring the absorbance of the reaction liquid, a data processing unit 203 for processing data measured by the light quantity measuring circuit 202, an input unit 204 as an interface with the data processing unit 203, and an output unit 205. The dispensing mechanism includes a sample dispensing mechanism 110 and a reagent dispensing mechanism 111.

[0013] The data processing unit 203 includes an information recording unit 2031 and an analysis unit 2032. The information recording unit 2031 stores control data, measurement data, data used in data analysis, analysis result data, and the like. The data processing unit 203 may be realized using a computer. The computer includes at least a processor such as a CPU (Central Processing Unit) and the information recording unit 2031. The processing of the analysis unit 2032 may be realized by storing program codes corresponding to those data processes in the information recording unit 2031 and having the processor execute each program code.

[0014] The input unit 204 and the output unit 205 input and output data to and from the information recording unit 2031. The input unit 204 is an information input device such as a keyboard, a touch panel, a numeric keypad, etc. The output unit 205 is a device, such as a display, that allows a user of the automatic analyzer to check the analysis results.

[0015] A plurality of sample cups 102 (sample containers) that contain samples 101 are arranged on the circumference of the sample disk 103. The samples 101 are, for example, blood. A plurality of reagent bottles 105 (reagent containers) that contain reagents 104 are arranged on the circumference of the reagent disk 106. A plurality of reaction cells 108 (reaction containers) that contain reaction liquid 107 obtained by mixing the sample 101 and the reagent 104 are mounted on the circumference of the reaction disk 109.

[0016] The sample dispensing mechanism 110 is a mechanism used when transferring a fixed amount of sample 101 from the sample cup 102 to the reaction cell 108. The sample dispensing mechanism 110 is composed of, for example, a nozzle that dispenses or aspirates a solution, a robot that positions and transports the nozzle to a predetermined position, a pump that dispenses or aspirates a solution from the nozzle or into the nozzle, and a flow path that connects the nozzle and the pump.

[0017] The reagent dispensing mechanism 111 is a mechanism used when transferring a fixed amount of reagent 104 from the reagent bottle 105 to the reaction cell 108. The reagent dispensing mechanism 111 is also composed of, for example, a nozzle that discharges or aspirates a solution, a robot that positions and transports the nozzle to a predetermined position, a pump that discharges or aspirates a solution from the nozzle or into the nozzle, and a flow path that connects the nozzle and the pump.

[0018] The stirring unit 112 is a mechanism for stirring and mixing the sample 101 and the reagent 104 in the reaction cell 108. The washing unit 114 is a mechanism for discharging the reaction liquid 107 from the reaction cell 108 after the analysis process has been completed, and then washing the reaction cell 108. After washing, the next sample 101 is dispensed into the reaction cell 108 again from the sample dispensing mechanism 110, and new reagent 104 is dispensed from the reagent dispensing mechanism 111, and the reaction cell 108 is used for another reaction process.

[0019] In the reaction disk 109, the reaction cell 108 is immersed in a constant temperature fluid 115 in a constant temperature bath in which the temperature and flow rate are controlled. Therefore, the reaction cell 108 and the reaction solution 107 therein are kept at a constant temperature by the control circuit 201 even while being moved by the reaction disk 109. The constant temperature fluid 115 is, for example, water or air.

[0020] An absorbance measuring unit 113 (absorption photometer) that performs absorbance analysis in the automatic analyzer is disposed on a portion of the circumference of the reaction disk 109.

[0021] 2 is a diagram showing the configuration of an absorbance measurement unit that performs absorbance analysis in an automatic analyzer. Light generated from a light source 301 for absorbance analysis is emitted along an optical axis 401, and is collected by a collecting lens 403 and irradiated onto a reaction cell 108. At this time, a light source side slit 402 may be arranged to uniformly distribute the amount of light within the irradiation surface, thereby restricting the width of the light emitted from the light source 301.

[0022] The light transmitted through the reaction solution 107 in the reaction cell 108 is split by a diffraction grating 3021 in the spectroscope 302 and received by a detector array 3022 equipped with a large number of light receivers. At this time, the light that has not transmitted through the reaction solution 107 becomes noise, so a spectroscope-side slit 404 may be provided to prevent such stray light from entering the spectroscope 302.

[0023] Examples of measurement wavelengths received by the detector array 3022 include 340 nm, 376 nm, 405 nm, 415 nm, 450 nm, 480 nm, 505 nm, 546 nm, 570 nm, 600 nm, 660 nm, 700 nm, 750 nm, 800 nm, etc. Light reception signals from these light receivers are transmitted to an information recording unit 2031 of the data processing unit 203 through the light quantity measuring circuit 202.

[0024] The amounts of components such as proteins, sugars, and lipids contained in the sample 101 are calculated according to the following procedure. First, the control circuit 201 instructs the cleaning unit 114 to clean the reaction cell 108. Next, the control circuit 201 causes the sample dispensing mechanism 110 to dispense a fixed amount of the sample 101 in the sample cup 102 into the reaction cell 108. Next, the control circuit 201 causes the reagent dispensing mechanism 111 to dispense a fixed amount of the reagent 104 in the reagent bottle 105 into the reaction cell 108.

[0025] When dispensing each solution, the control circuit 201 rotates the sample disk 103, the reagent disk 106, and the reaction disk 109 using the corresponding drive units. At this time, the sample cup 102, the reagent bottle 105, and the reaction cell 108 are positioned at a predetermined dispensing position according to the drive timing of the corresponding dispensing mechanism.

[0026] Next, the control circuit 201 controls the stirring unit 112 to stir the sample 101 and the reagent 104 dispensed into the reaction cell 108, thereby generating a reaction liquid 107. By the rotation of the reaction disk 109, the reaction cell 108 containing the reaction liquid 107 passes through a measurement position where an absorbance measurement unit 113 is disposed. Every time the reaction cell 108 passes through the measurement position, the amount of transmitted light from the reaction liquid 107 is measured by the absorbance measurement unit 113. The measurement data is sequentially output to the information recording unit 2031 and accumulated as reaction process data.

[0027] During the accumulation of this reaction process data, if necessary, another reagent 104 is additionally dispensed into the reaction cell 108 by the reagent dispensing mechanism 111, stirred by the stirring unit 112, and further measured for a certain period of time. In this way, the reaction process data acquired at a certain time interval is stored in the information recording unit 2031. EXAMPLES

[0028] The light source 301 used in the absorbance measurement unit 113 will be described in detail. Fig. 3 is a cross-sectional view showing the configuration of a light source according to Example 1. As shown in Fig. 3, the light source 301 according to this example includes a substrate 503, a temperature adjustment unit 504 that adjusts the temperature of the substrate 503, and a first LED 501 and a second LED 502 that are mounted on the substrate 503 on the opposite side to the temperature adjustment unit 504.

[0029] Here, as a method of absorbance analysis by an automatic analyzer, there is a two-wavelength measurement method that accurately quantifies the concentration of a measurement target by simultaneously measuring light of two wavelengths. In this measurement method, the more common the fluctuation characteristics of the light amount of each wavelength are, the higher the quantitative accuracy becomes. Therefore, in this embodiment, as shown in FIG. 3, by mounting multiple LEDs on a single substrate 503, each LED has the same temperature fluctuation characteristics by temperature control of the temperature adjustment unit 504, and it is possible to realize highly quantitative absorbance analysis.

[0030] The first LED 501 is a blue LED that emits light with a wavelength of about 385 nm, and the second LED 502 is an ultraviolet LED that emits ultraviolet light with a wavelength of about 340 nm. Furthermore, around the first LED 501, a phosphor 506 is provided that converts the excitation light of the first LED 501 into broadband light with a wavelength of 370 nm to 800 nm and emits the light.

[0031] In addition, the light source 301 of this embodiment has a dichroic filter 507 on the straight optical path of the first LED 501, which is incident at an angle of 45°, and further has a reflector 508, such as a mirror, on the straight optical path of the second LED 502, which is incident at an angle of 45°. The ultraviolet light from the second LED 502 reflected by the reflector 508 is reflected again by the dichroic filter 507, and is emitted from the light source 301 as a composite light along one optical path together with the light of 370 nm to 800 nm that is wavelength-converted by the phosphor 506 by the excitation light of the first LED 501. As a result, it is possible to obtain light of a wide wavelength band of 340 nm to 800 nm required for an automatic analyzer. Note that the light composition method shown in FIG. 3 is one example, and a method in which the positions of the dichroic filter 507 and the reflector 508 are mutually exchanged, a method in which another reflector is used, a method in which a light rod that mixes the light of two LEDs is used, and the like can be considered.

[0032] The substrate 503 has a role of supplying power to the first LED 501 and the second LED 502 and balancing the temperatures of the two LEDs and the temperature adjustment unit 504. When supplying power to the two LEDs, it is possible to reduce the noise difference between the LEDs by shorting the cathode side. In addition, from the viewpoint of promoting the thermal conduction between the temperature adjustment unit 504 and each LED, it is preferable that the substrate 503 is made of a metal such as aluminum or copper. In this way, the first LED 501 and the second LED 502 are mounted on a single metal substrate 503 with high thermal conductivity, and a common temperature fluctuation characteristic is obtained by the temperature control of the temperature adjustment unit 504. That is, the temperature of the first LED 501 and the second LED 502 can be relatively easily controlled by the temperature adjustment unit 504.

[0033] However, in the light source 301 of this embodiment, a phosphor 506 for converting the excitation light of the first LED 501 into wideband light and emitting it is provided on the substrate 503 so as to cover the first LED 501. Unlike the first LED 501, the temperature of this phosphor 506 is not easily adjusted by the temperature adjustment unit 504 alone. Therefore, in this embodiment, a temperature sensor 505 is embedded in the phosphor 506 together with the first LED 501. This makes it possible to directly measure the temperature of the phosphor 506, and facilitates temperature control including the phosphor 506, making it possible to stabilize the amount of light in a wide range of wavelength bands. The temperature sensor 505 is, for example, a thermistor, a thermocouple, a resistance temperature detector, a semiconductor sensor, etc. Also, it is possible to reduce the noise difference between the temperature sensor 505 and the LED by short-circuiting the ground side of the temperature sensor 505 and the cathode side of the LED.

[0034] The temperature adjustment unit 504 may be, for example, a metal block having a constant temperature fluid or a Peltier element. In the case of a Peltier element, the substrate 503 side of the temperature adjustment unit 504 may be controlled to a high degree of accuracy, for example, about 37±0.01° C., by feedback control of the temperature sensor 505 via the control circuit 201. In this case, it is preferable to place the temperature sensor 505 near the LED element to be controlled in order to improve the control accuracy. However, since the light source 301 of this embodiment is configured such that the first LED 501 and the second LED 502 are provided on the same substrate 503, the temperature sensor 505 is placed between these two LEDs, thereby enabling control with one temperature sensor 505. As a result, the amount of emitted light wavelength-converted by the phosphor 506 due to the excitation light of the first LED 501 and the amount of emitted light from the second LED 502 tend to have a common fluctuation characteristic.

[0035] FIG. 4 is a plan view showing an example of the arrangement of the temperature sensor. First, the positions of the first LED 501 and the second LED 502 on the substrate 503 are determined under the restrictions of the arrangement of optical components such as a dichroic filter, a mirror, and a lens. Next, the position of the temperature sensor 505 is determined based on the balance between the amount of heat generated by the first LED 501 and the amount of heat generated by the second LED 502. Specifically, the temperature sensor 505 is disposed so as to be closer to the one of the two LEDs that generates the larger amount of heat. Desirably, the temperature sensor 505 is disposed at a position where L is divided from O1 toward O2 at a ratio of Q2:Q1, where Q1 is the amount of heat generated by the first LED 501, Q2 is the amount of heat generated by the second LED 502, O1 is the center position of the first LED 501, O2 is the center position of the second LED 502, and L is the center distance. However, the premise is that the thermal conductivity of the substrate 503 is high enough to easily bring the heat generated by the first LED 501 and the heat generated by the second LED 502 into thermal equilibrium. In this way, the position where the temperature sensor 505 is placed is close to the temperature center of gravity, that is, the position corresponding to the average temperature of the light source 301, which is a structure consisting of each LED and its mounting substrate. Therefore, by feeding back this average temperature to the temperature adjustment unit 504 such as a Peltier element via the control circuit 201, the temperature of the light source 301 as a whole can be controlled with high precision, and the amount of light can be stabilized. In this embodiment, the light source having two LEDs has been described, but even if the light source has three or more LEDs, the temperature sensor may be placed in a position taking into account the ratio of the amount of heat generated by each LED, as described above.

[0036] Next, the experimental results when the light quantity is stabilized using the light source of this embodiment will be described. As experimental conditions, a blue LED (driven at a current of 600 mA) with a central wavelength of 385 nm was used for the first LED 501, and white light was emitted from the phosphor 506 by the excitation light, while an ultraviolet LED (driven at a current of 160 mA) with a central wavelength of 340 nm was used for the second LED 502. In addition, a dichroic filter 507 and a reflector 508 were arranged in the same manner as in the configuration shown in FIG. 3. Furthermore, a Peltier element having a cooling surface of 20 mm×20 mm was used for the temperature adjustment unit 504, and the temperature of the cooling surface was controlled to 37±0.01° C. Then, pattern wiring was applied via an insulating film (resist) on the aluminum substrate 503 on which each LED was mounted.

[0037] In this experiment, under such conditions, the placement location of the thermistor as the temperature sensor 505 is changed (in the comparative example and in the example 1), and the time until the light amount is stabilized is measured and compared. As a specific index, the light amount drift for 10 minutes at a single wavelength (how much the light amount changes in 10 minutes) is adopted, which is an index of stable absorption analysis. The single wavelengths are 340 nm, 376 nm, 415 nm, 450 nm, 480 nm, 505 nm, 546 nm, 570 nm, 600 nm, 660 nm, 700 nm, 750 nm, and 800 nm.

[0038] Fig. 5 is a plan view showing the arrangement of the temperature sensor in the light source of the comparative example. As shown in Fig. 5, in the light source of the comparative example, the temperature sensor 505 is not embedded in the phosphor 506, unlike in Example 1, but is located outside the phosphor 506.

[0039] Fig. 6 is a table showing the results of measuring the time from when the LED is turned on until the light quantity drift stabilizes. As shown in Fig. 6, it is understood that the time until the light quantity stabilizes is shorter in Example 1 than in the Comparative Example. It is considered that this result supports the idea that by embedding the temperature sensor 505 in the phosphor 506, the amount of light emitted from the phosphor 506 can be controlled with high precision, and the stabilization of the light quantity is accelerated.

[0040] Here, the means for stabilizing the light intensity will be described. As described above, in order to stably obtain the analytical performance of the absorption analysis of the automatic analyzer, it is preferable that the light intensity of the light source is constant. In this embodiment, the means for keeping the light intensity constant includes temperature control of the substrate 503 by the temperature adjustment unit 504 and drive current control of the LED.

[0041] For example, AlGaN crystals, which are compound semiconductors, are used as LEDs that generate ultraviolet light with wavelengths of 340 nm or less. When AlGaN crystals are used as the light-emitting layer, the light-emitting efficiency of ultraviolet LEDs is several times lower than that of InGaN crystals, which are used in the light-emitting layers of general white LEDs, and the light-emitting layer of AlGaN crystals has the characteristic that most of the input power becomes heat. In addition, the higher the temperature at which the LED is used and the longer the time it is used, the more defects are formed in the semiconductor crystals, and the more the light output of the LED decreases over time. Therefore, the life of LEDs using AlGaN crystals tends to be shorter than that of LEDs using InGaN crystals. In commercially available LEDs, the specification value of L70, the time it takes for the light output to decrease to 70%, is usually determined when the temperature of the bottom surface of the package is used at 25°C. For example, L70 is 10,000 hours or more, but it is known that L70 becomes shorter according to the Arrhenius model when the temperature of the LED increases. That is, by using a temperature adjustment unit 504 such as a Peltier element to lower the temperature of the board itself on which the LED is mounted, the light output can be increased and the life of the LED can be extended. The light output of the LED can also be increased by increasing the drive current.

[0042] FIG. 7 is a flowchart showing an example of a procedure for stabilizing the amount of light in the light source according to the first embodiment. As shown in FIG. 7, after the automatic analyzer is started (step S601), the light source 301 starts to turn on (step S602). Next, the dispensing mechanism dispenses water into any reaction cell 108 (step S603). Then, the absorbance measurement unit 113 executes the drive current control of the LED and the temperature control of the substrate 503 by the temperature adjustment unit 504 based on the temperature data acquired by the temperature sensor 505 (step S604). At this time, the absorbance measurement unit 113 performs the absorbance measurement for the reaction cell 108 (step S605) and judges whether or not the amount of light that satisfies the specified value is obtained (step S606). If the amount of light that satisfies the specified value is not obtained, the process returns to step S604, and the absorbance measurement unit 113 executes the drive current control of the LED and the temperature control of the substrate 503 by the temperature adjustment unit 504. Then, in step S606, if the amount of light obtained satisfies the specified value, absorbance analysis is started (step S607).

[0043] The absorbance measuring unit 113 is controlled by the control circuit 201, and the light amount data of the light amount measuring circuit 202 is acquired from the information recording unit 2031. As the temperature data, not only the temperature sensor 505 embedded in the phosphor 506 but also a temperature measured by another temperature sensor not embedded in the phosphor 506, for example, a temperature sensor that measures the installation environment temperature of the automatic analyzer, may be used. EXAMPLES

[0044] In the second embodiment, as a means for keeping the light quantity constant, in addition to temperature control of the substrate 503 by the temperature adjustment unit 504 and drive current control of the LED, heating control of the phosphor 506 by the heater 601 is provided. This embodiment is particularly effective when the temperature of the entire light source 301, particularly the temperature of the phosphor 506, is not sufficiently controlled only by the drive current control of the LED and the temperature adjustment unit 504 such as a Peltier element. Note that examples of the types of the heater 601 include a rubber heater, a film heater, a cartridge heater, and a sheath heater.

[0045] Fig. 8 is a cross-sectional view showing the configuration of a light source according to Example 2. As shown in Fig. 8, the light source 301 according to this example includes a substrate 503, a temperature adjustment unit 504 for adjusting the temperature of the substrate 503, a first LED 501 and a second LED 502 mounted on the substrate 503 on the opposite side of the temperature adjustment unit 504, and a heater 601 for directly heating the phosphor 506. Therefore, by feeding back temperature data acquired by the temperature sensor 505 to the control of the heater 601, the time from when the LED is turned on until the light amount becomes stable can be shortened.

[0046] Furthermore, after a certain period of time has elapsed since the automatic analyzer started operating, the light intensity of light source 301 becomes stable, and the temperature data at this time is measured by temperature sensor 505 and pre-recorded in information recording unit 2031. Therefore, if phosphor 506 is heated by heater 601 to reach that temperature, it is possible to efficiently stabilize the light intensity. In particular, if phosphor 506 is heated (pre-heated) by heater 601 before the LED starts to light up, the time until the light intensity becomes stable is further shortened.

[0047] 9 is a flow chart showing an example of a procedure for stabilizing the light quantity in the light source according to the second embodiment. First, the automatic analyzer is started (step S701). Next, based on data acquired by the temperature sensor 505, initial values ​​of the LED drive current value, the temperature setting value of the temperature adjustment unit 504 that controls the temperature of the substrate 503, and the temperature setting value of the heater 601 that preheats the phosphor 506 are determined (step S702). Next, when the light source starts to be turned on (step S703), the absorbance measurement unit 113 executes the LED drive current control, the temperature control of the substrate 503 by the temperature adjustment unit 504, and the temperature control of the phosphor 506 by the heater 601 based on the temperature data acquired by the temperature sensor 505 (step S704). Here, the analysis unit 2032 performs analysis using the data change over time of the temperature acquired from the temperature sensor 505 in step S705 and the change over time of the absorbance (amount of light) measured by the absorbance measurement unit 113 in step S706. Then, if the absorbance measurement unit 113 determines in step S707 that the amount of light does not satisfy the specified value, the LED drive current value, the temperature setting value of the temperature adjustment unit 504, and further the temperature setting value of the heater 601 are adjusted based on the analysis result of the analysis unit 2032. On the other hand, if the absorbance measurement unit 113 determines in step S707 that the amount of light satisfies the specified value, absorbance analysis is started (step S708).

[0048] For example, when the temperature setting value of the Peltier element, which is the temperature adjustment unit 504, is adjusted by PID control based on the analysis result of the analysis unit 2032, the PID parameters are determined using the temperature data measured by the temperature sensor 505. Here, when the environmental temperature is 25°C and the temperature setting value (target value) of the temperature adjustment unit 504 is 37°C, it takes time for the light amount to stabilize with temperature control targeting 37°C. Therefore, when the temperature data changes slowly over time (i.e., it seems that it will take time for the light amount to stabilize), it may be preferable to perform temperature control of PID parameters with a target value of, for example, 42°C. In this way, by acquiring and analyzing the temperature data changes over time at any time, it is possible to shorten the time until the light amount stabilizes.

[0049] The present invention is not limited to the above-described embodiment, but includes various modified examples. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration. [Explanation of symbols]

[0050] 101: sample, 102: sample cup, 103: sample disk, 104: reagent, 105: reagent bottle, 106: reagent disk, 107: reaction liquid, 108: reaction cell, 109: reaction disk, 110: sample dispensing mechanism, 111: reagent dispensing mechanism, 112: stirring unit, 113: absorbance measuring unit, 114: cleaning unit, 115: constant temperature fluid, 201: control circuit, 202: light quantity measuring circuit, 203: data processing unit, 2031: information recording unit, 2032 : Analysis section, 204: Input section, 205: Output section, 301: Light source, 302: Spectrometer, 3021: Diffraction grating, 3022: Detector array, 401: Optical axis, 402: Light source side slit, 403: Condenser lens, 404: Spectrometer side slit, 501: First LED, 502: Second LED, 503: Substrate, 504: Temperature adjustment section, 505: Temperature sensor, 506: Phosphor, 507: Dichroic filter, 508: Reflector, 601: Heater

Claims

1. A substrate; A first LED provided on the substrate; A phosphor that converts the excitation light of the first LED into broadband light; a second LED provided on the substrate; a temperature sensor is embedded in the phosphor together with the first LED; the temperature sensor is disposed between the first LED and the second LED and close to one of the first LED and the second LED which generates a larger amount of heat; The light source further comprises a heater for heating the phosphor.

2. 2. The light source according to claim 1, The light source according to claim 1, wherein the phosphor is heated by the heater before the first LED is turned on.

3. A substrate; A first LED provided on the substrate; A phosphor that converts the excitation light of the first LED into broadband light; A heater for heating the phosphor; a temperature adjustment unit located on the opposite side of the substrate from the first LED; a temperature sensor is embedded in the phosphor together with the first LED; A light source in which the first LED, the heater, and the temperature adjustment unit are controlled using the temperature measured by the temperature sensor.

4. 4. The light source according to claim 3, an environmental temperature sensor that is not embedded in the phosphor, separate from the temperature sensor; The light source according to claim 1, wherein the first LED, the heater, and the temperature adjustment unit are controlled using temperatures measured by the temperature sensor and the environmental temperature sensor.

5. 4. The light source according to claim 3, The light source according to claim 1, wherein the first LED, the heater, and the temperature adjustment unit are controlled in response to a change over time in temperature measured by the temperature sensor.

6. an absorbance measuring unit having the light source according to claim 1 or 3; and a reaction disk on which a reaction vessel containing a reaction liquid to be measured by the absorbance measuring unit is mounted.

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