Analytical device and method for determining the state of an LED light source.

Abstract

To accurately determine the status of an LED light source and predict when to replace the LED light source, regardless of individual differences in the LED light source or the conditions of the usage environment. [Solution] To solve the problem, the present disclosure proposes an analytical device comprising an LED light source that irradiates light onto a liquid in a container that holds the liquid to be analyzed, a photodetector that detects light emitted from the liquid by irradiating the liquid with light using the LED light source, and a data processing unit that executes processing to determine the state of the LED light source based on (i) the maximum light intensity during the period from when the LED light source is turned on until a predetermined time has elapsed until the amount of light from the LED light source stabilizes, (ii) the time it takes to reach the maximum light intensity, or (iii) the rate of change of the maximum light intensity relative to the time the LED light source is turned on.

Description

[Technical Field]

[0001] The present disclosure relates to an analysis device and a method for determining the state of an LED light source. [Background technology]

[0002] Analytical instruments can be used to analyze the amounts of components, such as proteins, sugars, lipids, enzymes, hormones, inorganic ions, and disease markers, contained in biological samples such as blood and urine. Analytical instruments typically dispense specimens and reagents into liquid containers and analyze test items based on changes in optical properties such as absorbance, fluorescence, and luminescence. In absorbance analysis using an analytical instrument, light from a light source is irradiated onto a sample or a reaction solution containing a mixture of sample and reagent, and the amount of transmitted light at one or more measurement wavelengths that passes through the sample or reaction solution is measured using a light-receiving element to calculate absorbance. The amount of a component can then be determined from the relationship between the calculated absorbance and concentration.

[0003] The light source for absorption spectrometry should have a wide emission spectrum to accommodate a large number of test items, and should be able to stably emit a certain amount of light at the measurement wavelength to enable highly accurate absorbance measurements. For this reason, xenon lamps, halogen lamps, etc. have traditionally been used.

[0004] In recent years, light-emitting diodes (hereinafter referred to as "LEDs"), which are expected to have a long lifespan, have been considered as light sources for absorption spectrometry in order to reduce the frequency of light source replacement. However, like xenon lamps and halogen lamps, even when LEDs are used as light sources for absorption spectrometry, the light-emitting chip, phosphor, resin, and other materials deteriorate over time, gradually reducing the amount of light emitted. Therefore, even when LED light sources are used, a method for determining the condition of LED light sources and a method for predicting when they should be replaced are needed.

[0005] Generally, when predicting the replacement time of an LED light source used in lighting fixtures, etc., the replacement time is determined to be when the light intensity of the LED light source falls below a threshold value of the initial light intensity (e.g., 70%). For example, Patent Document 1 discloses a technology that "integrates the lighting time of an LED while it is on, and notifies the user that the LED has reached the end of its life when the integrated lighting time reaches a preset life time." Patent Document 2 also discloses an "LED degradation measurement device that determines the degree of degradation of an LED based on the forward voltage-forward current characteristics of the LED." [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 10-39836 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-32793 Summary of the Invention [Problem to be solved by the invention]

[0007] However, if the degradation state or replacement time is determined to be when the light intensity of an LED light source falls below an initial light intensity threshold (e.g., 70%), as in conventional light source condition determination and replacement time prediction, the initial light intensity may vary due to individual differences between LED light sources. For example, even if the light intensity falls below the initial light intensity threshold, the variation in the initial light intensity may cause replacement even if the light intensity is sufficient to maintain the analytical performance of the analyzer. Furthermore, if the degradation state or replacement time is determined to be when the LED light source's lighting time reaches a preset lifespan, the individual differences between LED light sources and the environmental conditions of use may cause replacement even if the light intensity is sufficient to maintain the analytical performance of the analyzer. As such, conventional condition determination and replacement time prediction were unable to determine the state of an LED light source or predict its replacement time for each LED light source, even though the state of each LED light source varies depending on the individual differences between LED light sources and the environmental conditions of use.

[0008] Furthermore, utilizing the forward voltage-forward current characteristics as described in Patent Document 2 would require a new measurement system to monitor the current and voltage applied to the LED light source. Moreover, there is a need for a means to determine the state and predict the replacement time of an LED based on its characteristics, which can be measured in the shortest possible time without requiring significant time for measuring the LED's characteristics.

[0009] In light of these circumstances, this disclosure proposes a technology that accurately determines the state of an LED light source and predicts the replacement time for an LED light source, regardless of individual differences in LED light sources or the conditions of the operating environment. [Means for solving the problem]

[0010] To solve the above problems, this disclosure proposes an analytical apparatus comprising: an LED light source that irradiates light onto a liquid in a container containing a liquid to be analyzed; a photodetector that detects light emitted from a liquid by irradiating the liquid with light using the LED light source; and a data processing unit that performs a process to determine the state of the LED light source based on (i) the maximum light intensity during a predetermined time elapsed after the LED light source is turned on, until the amount of light from the LED light source stabilizes; (ii) the time to reach the maximum light intensity; or (iii) the rate of change of the maximum light intensity with respect to the power-on time of the LED light source.

[0011] Further features relating to this disclosure will become apparent from the description herein and the accompanying drawings. Furthermore, aspects of this disclosure are achieved and realized by elements and various combinations of elements and the aspects of the hereafter detailed description and the accompanying claims. The descriptions herein are exemplary and illustrative only and are not intended to limit the scope or application of the present disclosure in any way. [Effects of the Invention]

[0012] According to the technology disclosed herein, it is possible to accurately determine the state of an LED light source and predict when an LED light source needs to be replaced, regardless of individual differences in LED light sources or the conditions of the operating environment. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram showing an example of the overall configuration of an automatic analyzer 100. FIG. [Figure 2] FIG. 2 is a hardware block diagram of a data processing unit 203. [Figure 3] FIG. 10 is a diagram showing the contents (one example) of history data 2033a. [Figure 4] FIG. 2 is a diagram showing an example of the configuration of an absorbance measurement unit 113 that measures absorbance in the automatic analyzer 100. [Figure 5] 10 is a flowchart illustrating the operation of the automatic analyzer 100. [Figure 6] 10 is a flowchart illustrating details of the state determination process (S506). [Figure 7] 10 is a flowchart for explaining details of the replacement time prediction process (S507). [Figure 8] FIG. 10 is a diagram showing the results of fluctuations in light intensity immediately after turning on white LEDs with different power-on times. [Figure 9] 10 is a diagram showing the correlation between the power-on time of an LED and the maximum light intensity until the light intensity from an LED light source stabilizes. FIG. [Figure 10] FIG. 10 is a diagram showing the correlation between the power-on time of an LED and the time it takes for the amount of light from an LED light source to stabilize and reach its maximum light amount. [Figure 11] FIG. 10 is a diagram showing the results of fluctuations in light intensity after the white LED is turned on (1800 seconds after being turned on) before and after data correction. DETAILED DESCRIPTION OF THE INVENTION

[0014] Embodiments of this disclosure propose determining the state of an LED light source and predicting the replacement time of an LED light source based on the maximum light intensity until the light intensity stabilizes after a certain period of time from the time the LED light source is switched on, the time to reach the maximum light intensity, or the rate of change of the maximum light intensity with respect to the power-on time of the LED light source. Embodiments of this disclosure will be described in detail below with reference to the drawings. In these embodiments, it goes without saying that the components (including element steps, etc.) are not necessarily essential unless specifically indicated or considered to be clearly essential in principle.

[0015] (Automatic analyzer 100) The outline of the automated analyzer 100 of this embodiment will be explained using Figure 1. The automated analyzer 100 in Figure 1 comprises 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; and a control unit 201 for controlling these. The automated analyzer 100 also comprises a light intensity measurement circuit 202 for measuring the absorbance of the liquid (reaction solution) to be analyzed; a data processing unit 203 for processing the measurement data measured by the light intensity measurement circuit 202; and an input unit 204 and an output unit 205 which are interfaces with the data processing unit 203. The data processing unit 203 can be configured as a computer. The dispensing mechanism includes a sample dispensing mechanism 110 and a reagent dispensing mechanism 111.

[0016] The data processing unit 203 stores the measurement data measured by the light quantity measurement circuit 202 and analyzes the stored measurement data. The analysis results are output to, for example, the output unit 205. The details of the data processing unit 203 will be described later.

[0017] The input unit 204 and output unit 205 input and output data to and from the data processing unit 203. The input unit 204 is an information input device such as a keyboard, a touch panel, or a numeric keypad. The output unit 205 is an information output device, such as a display, for outputting the analysis results of the automatic analyzer 100.

[0018] A plurality of sample cups 102, which are containers for holding 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, which are containers for holding reagents 104, are arranged on the circumference of the reagent disk 106. A plurality of reaction cells 108, which are containers for holding reaction solutions 107 to be analyzed, which are mixtures of the samples 101 and the reagents 104, are arranged on the circumference of the reaction disk 109.

[0019] The sample dispensing mechanism 110 is a mechanism used to transfer 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, and a flow path that connects the nozzle and the pump.

[0020] 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 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, and a flow path that connects the nozzle and the pump.

[0021] The solution stirring unit 112 is a mechanism that stirs and mixes the sample 101 and the reagent 104 in the reaction cell 108. The washing unit 114 is a mechanism that discharges the reaction solution 107 from the reaction cell 108 after the analysis process has been completed, and then washes the reaction cell 108. After the washing process is completed, the next sample 101 is dispensed into the reaction cell 108 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.

[0022] In the reaction disk 109, the reaction cell 108 is immersed in a constant-temperature fluid 115 in a constant-temperature bath with controlled temperature and flow rate. Therefore, the temperature of the reaction cell 108 and the reaction solution 107 within it is kept constant by the control unit 201 even while it is being moved by the reaction disk 109. For example, water or air can be used as the constant-temperature fluid 115.

[0023] An absorbance measurement unit 113 that performs absorbance analysis in the automatic analyzer 100 is disposed on a portion of the circumference of the reaction disk 109 .

[0024] (Data processing unit 203) Figure 2 is a hardware block diagram of the data processing unit 203. The data processing unit 203 includes a processor 2031, a main memory unit 2032, an auxiliary memory unit 2033, and an input / output interface 2034. The processor 2031 is a CPU (Central Processing Unit), GPU (Graphics Processing Unit), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), etc. The main memory unit 2032 is a DRAM (Dynamic Random Access Memory), etc., and is used as a working area for the processor 2031. The auxiliary memory unit 2033 is an HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof, etc., and stores various programs and various data. The input / output interface 2034 is an interface that enables communication between the data processing unit 203 and its peripheral devices (e.g., control unit 201, light intensity measurement circuit 202, input unit 204, output unit 205).

[0025] The auxiliary storage unit 2033 of this embodiment stores history data 2033a, a status determination program 2033b, and a replacement time prediction program 2033c. The status determination program 2033b is a program that determines the status of the LED light source 301 (see FIG. 4) using the maximum light intensity X (hereinafter referred to as "maximum light intensity X") until the light intensity from the LED light source 301 stabilizes. Here, "the light intensity stabilizes" refers to the LED light source 301 being in a state where analysis is possible, such as a state after a predetermined time (e.g., 30 minutes) has elapsed since the automatic analyzer 100 was started. Furthermore, when the light intensity in a stable state (a state where analysis can be properly performed) is set to 100, the light intensity in the stable state falls within a range of 100±0.2% (0.2%: 0.2% of the light intensity when 100 is used). In this embodiment and the embodiments described later, the LED light source 301 is assumed to be composed of an LED chip and a phosphor (for example, the maximum light intensity X described later refers to the maximum light intensity from the LED chip and phosphor), and the operation and other aspects will be explained accordingly. However, the technology of this disclosure is also applicable to light sources composed of an LED chip alone.

[0026] The processor 2031 executes the state determination program 2033b to determine the state of the LED light source 301 using the maximum light intensity X until the light intensity from the LED light source 301 stabilizes, and outputs the determination result. The replacement time prediction program 2033c is a program that predicts the replacement time of the LED light source 301 based on the correlation between the maximum light intensity X and the power-on time T of the LED light source 301. The processor 2031 executes the replacement time prediction program 2033c to predict the replacement time of the LED light source 301 using the maximum light intensity X until the light intensity from the LED light source 301 stabilizes, and outputs the prediction result.

[0027] Furthermore, the auxiliary storage unit 2033 may store measurement data measured by the light intensity measurement circuit 202, an analysis program for analyzing the measurement data, and the analysis results obtained by the analysis program.

[0028] Figure 3 shows the contents of the history data 2033a. The history data 2033a stores the power-on time T of the LED light source 301 and the maximum light intensity X measured during that power-on time T, within the period until the light intensity from the LED light source 301 stabilizes (for example, during the first 30 minutes after restart), in association with each other. In the example in Figure 3, the maximum light intensity is shown calculated using the relative light intensity value (%) when the light intensity at the start of power-on (0 hours of power-on) is set to 100%. However, when showing the light intensity as a relative value, the reference light intensity used as 100% does not have to be the light intensity at the start of power-on (0 hours of power-on). Also, the light intensity does not have to be a relative value; the photocurrent value acquired by the device may be used. In the example in Figure 3, the maximum light intensity X is measured every 3000 hours, but the measurement interval for the maximum light intensity X is not limited to 3000 hours; it may be shorter or longer than 3000 hours. Furthermore, in the example in Figure 3, the maximum light intensity X is measured at equal intervals, but the measurement interval for the maximum light intensity X does not have to be equal. Also, instead of the energizing time T of the LED light source 301, or in addition to the energizing time T of the LED light source 301, the operating time of the automatic analyzer 100 may be used. As shown in Figure 3, the maximum light intensity at 1000 hours of energizing time and then every 3000 hours thereafter is recorded as history data 2033a, but the maximum light intensity may be measured each time the automatic analyzer 100 is started (restarted) and recorded as history data 2033a. By taking history data 2033a each time it is started, the amount of data can be increased when determining the approximate straight line (approximate curve) described later, and a more accurate approximate straight line (approximate curve) can be determined.

[0029] When a new maximum light amount X is measured, the measured maximum light amount X is stored in association with the power supply time T in a new record of the history data 2033a.

[0030] (Absorbance measurement section 113) 4 is a diagram showing an example of the configuration of the absorbance measurement unit 113 that measures absorbance in the automatic analyzer 100. In the automatic analyzer 100 of this embodiment, an LED light source 301 is used as the light source unit for absorbance measurement. The illumination light generated from the LED light source 301 is emitted along an optical axis 401, condensed by a condenser lens 403, and irradiated onto the reaction solution 107 in the reaction cell 108. At this time, a light source-side slit 402 may be arranged to limit the width of the light emitted from the LED light source 301 in order to uniformly distribute the light amount within the illumination surface of the light.

[0031] The light transmitted through the reaction solution 107 in the reaction cell 108 is dispersed by a diffraction grating 3021 in the spectroscope 302 and received by a detector array 3022 having a large number of light receivers. The detector array 3022 is an example of a photodetector. At this time, since light that has not transmitted through the reaction solution 107 becomes noise, a spectroscope-side slit 404 may be provided to prevent such stray light from entering the spectroscope 302. In this embodiment, the detector array 3022 detects the light transmitted through the reaction solution 107, but the detector array 3022 (photodetector) may also detect light emitted from the reaction solution 107 (for example, optical properties such as light absorption, fluorescence, and light emission).

[0032] The detector array 3022 receives light of a plurality of measurement wavelengths (capable of measuring light of a plurality of wavelengths). The light received by the detector array 3022 is converted into an electrical signal (light-receiving signal) and stored as measurement data in the auxiliary memory unit 2033 of the data processing unit 203 via the light quantity measurement circuit 202.

[0033] On the other hand, the absorbance measurement unit 113 is also used to measure the maximum light intensity X until the light intensity of the light from the LED light source 301 stabilizes. When measuring the maximum light intensity X, the reaction cell 108 is not placed on the optical axis 401, or the reaction cell 108 is placed without containing the reaction solution 107. The irradiated light generated from the LED light source 301 is emitted along the optical axis 401 and condensed by the condenser lens 403. The condensed light is dispersed by the diffraction grating 3021 and received by the detector array 3022. The light received by the detector array 3022 is converted into an electrical signal (light-receiving signal) and stored as history data 2033a in the auxiliary memory unit 2033 of the data processing unit 203 via the light intensity measurement circuit 202.

[0034] (Example of control of the automatic analyzer 100 by the control unit 201) The amounts of components such as proteins, sugars, and lipids contained in the sample 101 are calculated, for example, by the following procedure. First, the control unit 201 instructs the cleaning unit 114 to clean the reaction cell 108. Next, the control unit 201 instructs 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 unit 201 instructs the reagent dispensing mechanism 111 to dispense a fixed amount of the reagent 104 in the reagent bottle 105 into the reaction cell 108.

[0035] When dispensing each solution, the control unit 201 instructs the drive units of each disk to rotate the sample disk 103, the reagent disk 106, and the reaction disk 109. At this time, the sample cup 102, the reagent bottle 105, and the reaction cell 108 are positioned at predetermined dispensing positions according to the drive timing of the corresponding dispensing mechanism.

[0036] Next, the control unit 201 instructs the solution stirring unit 112 to stir the sample 101 and reagent 104 dispensed into the reaction cell 108 to generate the reaction solution 107. As the reaction disk 109 rotates, the reaction cell 108 containing the reaction solution 107 passes through the measurement position where the absorbance measuring unit 113 is located. Each time it passes through the measurement position, the amount of light transmitted from the reaction solution 107 is measured via the absorbance measuring unit 113. The measurement data is sequentially output to the auxiliary storage unit 2033 and stored as reaction process data.

[0037] 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 solution stirring unit 112, and further measured for a certain period of time. As a result, the reaction process data acquired at certain time intervals is stored in the auxiliary memory unit 2033.

[0038] (Operation of the automatic analyzer 100) Figure 5 is a flowchart illustrating an example of the operation of the automated analyzer 100. When the power of the automated analyzer 100 is turned ON (S501), it starts a warm-up process (S502). The warm-up process includes starting various software and checking the operation of each part before analysis. The time required for this warm-up process is called the warm-up time. In Figure 5, the processes from S502 to S507 correspond to the warm-up process.

[0039] The automated analyzer 100 turns on the LED light source 301 during the warm-up process (S503). The amount of light emitted from the LED light source 301 requires time (a predetermined time: for example, 30 minutes) to stabilize after the LED light source 301 is turned on. At least until the warm-up process is complete (until the LED light source 301 stabilizes), the light from the LED light source 301 is not used for absorbance analysis. The maximum light intensity X is due to the rise characteristics of the LED light source 301 and differs for each LED used in the LED light source 301. In this embodiment, we focus on these rise characteristics of the LED light source 301 and use the maximum light intensity X due to the rise characteristics of the LED light source 301 to predict the state of the LED light source 301 and the timing of its replacement.

[0040] The absorbance measurement unit 113 measures the light intensity of the LED light source 301 during the warm-up process (a period of 30 minutes from the start-up of the automatic analyzer 100 (turning on of the LED light source 301)). Then, the data processing unit 203 calculates the maximum light intensity X based on the measured light intensity (S504).

[0041] The data processing unit 203 associates the calculated maximum light intensity X with the power-on time T of the LED light source 301 (the total power-on time up to the current startup of the automatic analyzer 100) and stores them in the history data 2033a (S505). The power-on time T of the LED light source 301 is stored, for example, in the auxiliary storage unit 2033 of the data processing unit 203. The data processing unit 203 acquires the power-on time T of the LED light source 301 stored in the auxiliary storage unit 2033, and associates the calculated maximum light intensity X with the acquired power-on time T of the LED light source 301 and stores them in the history data 2033a.

[0042] Then, the data processing unit 203 executes a state determination process (S506) to determine the state of the LED light source 301. Details of the state determination process will be described later (see FIG. 6).

[0043] Furthermore, the data processing unit 203 executes a replacement time prediction process (S507) for predicting when to replace the LED light source 301. Details of the replacement time prediction will be described later (see FIG. 7).

[0044] The automatic analyzer 100 of this embodiment executes both the state determination process (S506) and the replacement time prediction process (S507), but may execute only one of the state determination process (S506) or the replacement time prediction process (S507).

[0045] Once the warm-up process is complete and the automatic analyzer 100 is ready to perform analysis, the automatic analyzer 100 irradiates the reaction solution 107 with light from the LED light source 301 and begins absorbance analysis to measure the absorbance of the reaction solution 107 in the reaction cell 108 (S508).

[0046] (Details of S506: LED light source 301 status determination method) Fig. 6 is a flowchart showing details of the state determination process. For example, the processor 2031 of the data processing unit 203 executes the state determination program 2033b stored in the auxiliary storage unit 2033, thereby executing each step of the flowchart in Fig. 6.

[0047] The data processing unit 203 compares the maximum light intensity X calculated in S504 with a preset reference value (set as a value that will not interfere with analysis) (S601). The reference value is stored in advance in, for example, the auxiliary storage unit 2033 of the data processing unit 203.

[0048] The data processing unit 203 determines whether the maximum light amount X is equal to or less than a reference value according to the comparison result of S601 (S602).

[0049] If it is determined that the maximum light intensity X is equal to or less than the reference value (S602: Yes), the data processing unit 203 identifies the state of the LED light source 301 (S603). For example, the data processing unit 203 may identify the state of the LED light source 301 based on the magnitude of the difference between the maximum light intensity X and the reference value, or may identify the state of the LED light source 301 based on the maximum light intensity X. The state of the LED light source 301 may be, for example, a degradation state indicating the degree of degradation of the LED light source 301, a usage state indicating the degree of use of the LED light source 301, or the like.

[0050] The data processing unit 203 outputs (displays) the identified state of the LED light source 301 to the output unit 205 (display) (S604).

[0051] On the other hand, if the maximum light intensity X is determined to be greater than the reference value (S602: No), the data processing unit 203 outputs (displays) a warning to the output unit 205 (display) (S605). For example, the data processing unit 203 may display a warning on the output unit 205 (display) prompting the replacement of the LED light source 301, or a warning indicating that it is time to replace the LED light source 301. The data processing unit 203 may also output light or sound from the output unit 205 (lamp or speaker) that outputs the status of the LED light source 301, prompting the replacement of the LED light source 301, or light or sound indicating that it is time to replace the LED light source 301. In addition, upon receiving such a warning, the user can check whether there is a problem with the LED light source 301.

[0052] In the example shown in Figure 6, although the absorbance analysis in S508 can be performed after the warning is issued (S605), the performance of the absorbance analysis in S508 may be prohibited if the warning is issued. Alternatively, the results of the absorbance analysis performed after the warning is issued may be managed separately from the results of the absorbance analysis performed without the warning.

[0053] Furthermore, in the process shown in Figure 6, the state of the LED light source 301 is determined using the maximum light intensity X, but the time t from the start (restart) of the automatic analyzer 100 until the maximum light intensity X is reached is also considered. max and a preset time reference value t TH (S601'), and time t max is the time reference value t TH In the above case (the state in which the upper time limit in FIG. 10 has already been reached) (S602'), a warning may be output (S605).

[0054] (Method for predicting replacement time of LED light source 301) Figure 7 is a flowchart showing the details of the replacement timing prediction process. For example, the processor of the data processing unit 203 executes each step of the flowchart in Figure 7 by executing the replacement timing prediction program 2033c stored in the auxiliary storage unit 2033.

[0055] First, the data processing unit 203 refers to the history data 2033a in the auxiliary storage unit 2033 (S701).

[0056] The data processing unit 203 acquires the maximum light intensity X for each power-on time T of the LED light source 301 from the history data 2033a, and derives an approximate line using the acquired maximum light intensity X for each power-on time T of the LED light source 301 (in the case of Example 1 described below) or using the time t until the maximum light intensity X for each power-on time T is reached (in the case of Example 2 described below) (S702). This approximate line is derived using the least squares method or the like. Note that, although linear approximation is performed in the example of FIG. 7, exponential approximation, logarithmic approximation, polynomial approximation, power approximation, or moving average approximation may also be performed. Furthermore, the accuracy of the approximation can be further improved by correcting the light intensity data by multiplying it by a coefficient based on environmental data such as temperature and humidity.

[0057] The data processing unit 203 predicts the replacement timing for the LED light source 301 from the derived approximation line (S703). For example, the data processing unit 203 calculates the energizing time T until the approximation line reaches the upper limit of the maximum light intensity X, and sets the calculated energizing time T as the replacement timing.

[0058] Then, the data processing unit 203 outputs (displays) the replacement timing on the output unit 205 (display) (S704). For example, the data processing unit 203 outputs (displays) on the output unit 205 (display) as the replacement timing the remaining power-on time until the LED light source 301 is replaced, the remaining operating time of the automatic analyzer 100, the replacement date and time when replacement of the LED light source 301 is recommended, etc.

[0059] (Effects of this embodiment) In this embodiment, by using the maximum light intensity X (rise-time characteristic) of the LED light source 301, it is possible to determine the condition of each individual LED light source 301 and predict the replacement time, while reflecting the state of the LED light source 301 that changes over time with the power supply duration. This makes it possible to reduce the frequency of LED light source 301 replacement, thereby reducing the maintenance costs required for light source replacement and the workload of operators beyond routine tasks. Furthermore, it reduces the number of light sources that are discarded simply because their operating time has exceeded a certain period, even if the light intensity is still sufficient, thus contributing to a reduction in environmental impact.

[0060] Furthermore, unlike the aforementioned Patent Document 2, this embodiment does not require a new measurement system for monitoring the current and voltage applied to the LED light source 301.

[0061] Next, the method for determining the state of the LED light source 301 and predicting its replacement time will be described below with reference to Examples 1 and 2. In this disclosure, the state of the LED light source 301 and the replacement time are predicted by utilizing the knowledge that there is a difference in the maximum light output from the time the LED lights up until the light output stabilizes, depending on the power-on time of the LED light source 301. [Example]

[0062] Example 1 proposes predicting the replacement timing of the LED light source 301 based on the phenomenon that there is a difference in the maximum light intensity until the light intensity from the LED light source 301 stabilizes, depending on the energizing time T of the LED. Therefore, the light intensity fluctuation from the time of ignition until the light intensity stabilizes sufficiently for the LED used in the light source unit (LED light source 301) was measured using an integrating sphere. Here, a white LED was used in which light is emitted from a light-emitting chip that emits ultraviolet light and a phosphor placed on the light-emitting chip, emitting light with a wide range of wavelengths (approximately 370 nm to 800 nm). In order to keep the LED temperature constant, a Peltier element was used to control the temperature of the LED mounting substrate to a constant temperature.

[0063] FIG. 8 shows the results of the light intensity fluctuations immediately after the white LED was turned on (120 seconds after turning it on) for each power-on time (4,000 hours, 7,000 hours, and 10,000 hours). The horizontal axis represents the time (seconds) since the LED was turned on, and the vertical axis represents the relative light intensity (%), where the light intensity at the start of power-on (power-on time 0) is 100%. In Example 1, the light intensity fluctuations during 120 seconds after the LED was turned on were used as an example of the light intensity fluctuations until the light intensity stabilizes after a certain time has elapsed since the LED light source was turned on. Here, the light intensity from the LED light source is defined as stabilizing 30 minutes after turning it on, and the light intensity fluctuations during 120 seconds after turning it on were used, which is significantly shorter than that. However, the definitions of "after a certain time has elapsed" and "until the light intensity stabilizes" are not limited to these and may be determined depending on the size of the automated analyzer. For example, the certain time is much shorter than the warm-up time required for the automated analyzer 100 to be ready for measurement after startup. In this way, the state of the LED light source 301 and the timing of its replacement can be determined during the initial stages of the warm-up period, thereby preventing a decrease in the throughput of the absorbance analysis.

[0064] In Example 1, the maximum light intensity X was calculated for each power-on time T. In the example shown in Figure 8, the values ​​were 100.55%, 102.33%, and 102.83% after 4,000, 7,000, and 10,000 hours of power-on, respectively. This confirms the phenomenon that the maximum light intensity increases with increasing power-on time from when the LED is turned on until the light intensity stabilizes. The wavelength used here is 376±5 nm, which is close to the wavelength of the light-emitting chip that constitutes the white LED used in automated analyzers. The above findings are believed to reflect the aging of both the light-emitting chip and the phosphor that constitute the white LED. The light-emitting chip and the phosphor are thought to age at different rates, and it is speculated that the light emission from the phosphor is more likely to decrease with power-on than the light emission from the chip. Here, a portion of the light emitted from the chip is absorbed by the phosphor as excitation light, but as the power is applied, the absorption by the phosphor decreases, and it is believed that this phenomenon has been confirmed, resulting in an increase in the amount of light emitted at 376±5 nm, which is a wavelength relatively close to that of the chip. Therefore, it is desirable to limit the use of wavelengths close to that of the light-emitting chip among the wavelengths of an LED consisting of a light-emitting chip and a phosphor, as in Example 1.

[0065] Figure 9 shows the correlation between the LED energizing time T and the maximum light intensity X from LED ignition to stabilization. Regarding wavelength, as above, the maximum light intensity X was calculated for light intensity fluctuations at a wavelength close to the wavelength of the light-emitting chip, 376±5nm. Similar to the results in Figure 8, it was confirmed that the maximum light intensity from LED ignition to stabilization increases as the energizing time increases, indicating an approximately linear correlation between the LED energizing time T and the maximum light intensity X. Therefore, even in the LED light source 301 mounted on the automated analyzer, the correlation between the maximum light intensity X and the energizing time T can be represented by an approximate straight line calculated from multiple actual data, as shown by the solid line in Figure 9. From this approximate straight line, the energizing time T1 at which the maximum light intensity X exceeds a predetermined upper limit (the maximum light intensity value when the LED is in a state requiring replacement (degraded state)) is calculated, and this T1 is designated as the replacement time. Note that in some cases, an approximate curve may yield a higher correlation coefficient than an approximate straight line; therefore, the method of calculating the correlation can be appropriately changed depending on the operation of each device. It is believed that there are individual differences in the initial light output and internal state of LED elements. In Example 1, by deriving the correlation between the maximum light output X and the energizing time T from actual data for each LED used in the LED light source 301, the optimal replacement time for each individual can be calculated, making it possible to reduce the frequency of replacement of the LED light source 301. [Example]

[0066] Example 2 demonstrates an example of predicting the replacement timing based on the phenomenon that there is a difference in the time it takes to reach the maximum light intensity from the LED light source 301 until the light intensity stabilizes, depending on the energizing time T of the LED. Similar to Example 1, a white LED was used in which light is emitted from a light-emitting chip that emits ultraviolet light and a phosphor placed on the light-emitting chip, emitting light with a wide range of wavelengths (approximately 370 nm to 800 nm). The light intensity fluctuation of the LED used in the light source (LED light source 301) from the time of ignition until the light intensity stabilized was measured using an integrating sphere. In order to keep the LED temperature constant, a Peltier element was used to control the temperature of the LED mounting substrate.

[0067] Figure 10 shows the correlation between the LED power-on time T and the time t required for the LED to reach maximum light intensity after activating and stabilizing. As in Example 1, the time t required for the LED to reach maximum light intensity was calculated for fluctuations in light intensity at 376±5 nm, a wavelength close to the wavelength of the light-emitting chip. As a result, it was confirmed that the time t required for the LED to reach maximum light intensity after activating and stabilizing increased with increasing power-on time. As in Example 1, this is likely due to aging of the light-emitting chip and phosphor, resulting in a characteristic change dependent on the power-on time T. Therefore, this result indicates that there is a difference in the fluctuation in light intensity when the LED is lit depending on the power-on time, and this value can be used as a criterion for determining when to replace the LED. For the LED light source 301 installed in an automated analyzer, the correlation between the time t required for the LED to reach maximum light intensity and the power-on time T can be expressed by an approximate straight line calculated from multiple actual data, as shown by the solid line in Figure 10. From this approximate line, the power-on time T1 at which the time t until the maximum light output exceeds a predetermined upper limit is calculated (when the approximate line function is expressed as time t = a × power-on time T + b, the T obtained when t = upper limit is substituted becomes T1), and T1 can be set as the replacement time. Note that in some cases, the correlation coefficient may be higher with an approximate curve rather than an approximate line, so the method of calculating the correlation can be changed appropriately depending on the operation of each device.

[0068] Furthermore, even if the maximum light intensity is equal to or less than the upper limit in Example 1, if the time taken to reach the maximum light intensity exceeds the upper limit in Example 2, the system may be configured to interrupt the absorption analysis. That is, by combining a comparison of the measured value of the maximum light intensity with the upper limit and a comparison of the measured value of the time taken to reach the maximum light intensity with the upper limit, it is possible to realize prediction of the replacement time in accordance with the analytical performance required for absorption analysis. [Example]

[0069] Example 3 demonstrates an example in which more accurate predictions are possible by correcting the light intensity data after lighting based on LED temperature data. It is known that the luminous efficiency and light intensity of an LED's light-emitting chip and phosphor change depending on the temperature of the mounting substrate and the ambient temperature. Because these changes in luminous efficiency and light intensity affect the stability of the light intensity, it is believed that highly accurate predictions are possible by acquiring the light intensity in a sufficiently stable temperature environment. In Example 3, to maintain a constant LED temperature, a Peltier element was used to control the LED mounting substrate at a constant temperature. Furthermore, the light intensity data after lighting of the LED was corrected based on temperature data acquired from a thermistor on the mounting substrate. As in Examples 1 and 2, a white LED was used, which emits ultraviolet light from a light-emitting chip and a phosphor mounted on the light-emitting chip, emitting light over a wide wavelength range (approximately 370 nm to 800 nm). The fluctuations in light intensity of the LED used in the light source unit (LED light source 301) from lighting until the light intensity stabilized were measured using an integrating sphere.

[0070] Figure 11 shows the results of the light intensity fluctuation after the white LED was turned on (1800 seconds after turning it on) before and after data correction. The horizontal axis represents the time (seconds) since the LED was turned on, and the vertical axis represents the relative light intensity (%) when the light intensity 1800 seconds (30 minutes) after the LED was turned on is set to 100%. In Example 3, the light intensity from the LED light source is defined as stabilizing 30 minutes after turning it on. As an example of the light intensity fluctuation until the light intensity stabilizes after a certain time has elapsed since the LED light source was turned on, the light intensity fluctuation 1800 seconds after the LED was turned on is used. As with Examples 1 and 2, the light intensity fluctuation at 376±5 nm, which is close to the wavelength of the light-emitting chip, is shown. The figure before correction also shows the temperature fluctuation after the LED was turned on. The horizontal axis represents the time (seconds) since the LED was turned on, and the vertical axis represents the temperature (°C) obtained from the thermistor on the mounting board.

[0071] In Example 3, although a Peltier element is used to control the LED mounting substrate to a constant temperature, it can be seen that the thermistor temperature on the mounting substrate fluctuates by approximately ±0.15°C (Figure 11(a)). Before data correction, a decrease in light intensity was observed after 480 seconds, when the temperature of the mounting substrate began to rise. This is thought to be because the forward voltage of the LED element decreases as the temperature rises, reducing its luminous efficiency, and consequently, the light intensity at 376±5nm, a wavelength close to the wavelength of the light-emitting chip, decreased.

[0072] For state determination and replacement timing prediction using the rise time light intensity characteristics of the LED light source disclosed in this disclosure, it is essential to isolate these temperature-induced light intensity fluctuations and evaluate only the rise time light intensity fluctuations. The correlation between the mounting substrate temperature and light intensity for each wavelength is known from actual measurement data on the device. The light intensity fluctuation rate due to substrate temperature was calculated, and the "corrected" light intensity was evaluated assuming a constant substrate temperature. The light intensity fluctuation rate due to substrate temperature can be calculated by recording the temperature and light intensity of the mounting substrate when the light intensity stabilizes after a sufficient amount of time has elapsed since the LED light source was turned on, and then performing a linear approximation of the temperature change and the light intensity change.

[0073] The method for calculating the rate of change in light intensity due to temperature is not limited to this, and exponential approximation, logarithmic approximation, polynomial approximation, power approximation, or moving average approximation may also be used. Furthermore, the temperature variable used is not limited to the temperature of the mounting board, and the ambient temperature within the device or the temperature of peripheral components may also be used.

[0074] In the corrected light intensity fluctuations shown in Figure 11(b), it is confirmed that the light intensity remains stable even after 480 seconds, when a decrease in light intensity was observed before correction, demonstrating that it is possible to eliminate the effects of temperature. Such temperature-based data correction is very effective in accurately evaluating the rise light intensity immediately after LED illumination used in the prediction method of this disclosure, and is expected to further improve the accuracy of the approximate derivation.

[0075] Furthermore, in the third embodiment, correction is performed using temperature data, but it is also possible to correct the light intensity data by multiplying it by a coefficient based on environmental data such as humidity.

[0076] (i) Variation 1 In the state determination process of this embodiment shown in Fig. 6, the state of the LED light source 301 is determined based on the comparison result between the reference value and the maximum light intensity X (S601 → S602), but the absolute value of the rate of change of the maximum light intensity may be compared with a predetermined reference change rate threshold value, and the state determination may be performed based on the comparison result. k (Total power-on time T until the device is started up this time) k ) and the maximum light intensity X at the time of the previous device startup. k-1 (Total power-on time T until the last device startup) k-1 If the following equation holds, there is a possibility that the condition of the LED light source 301 is deteriorating, so a warning may be output (S605). This warning is to address situations such as sudden cracks occurring in the LED chip or phosphor.

[0077] |(X k -X k-1 ) / (T k -T k-1 )|≧ Reference rate of change threshold

[0078] Upon receiving the warning, the user can interrupt the analysis performed by the automated analyzer 100, check the LED light source 301 included in the automated analyzer 100, and replace the LED light source 301 with a new LED light source if necessary.

[0079] (ii) Variation 2 In the above embodiment, the maximum light intensity X of the LED light source 301 or the time t until the maximum light intensity is reached is calculated during the warm-up process, and the state determination process and replacement time prediction process for the LED light source 301 are executed, but the timing for executing the state determination process and replacement time prediction process is not limited to during the warm-up process. For example, the state determination process and replacement time prediction process for the LED light source 301 may be executed during the maintenance mode, or may be executed after a certain time has elapsed or after a certain number of inspections have been performed.

[0080] (iii) Other The technology of the present disclosure is not limited to the above-described embodiments, examples, and modifications, but includes various other modifications. The above-described embodiments and examples have been described in detail to clearly explain the present disclosure, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one example with the configuration of another example, or to add the configuration of another example to the configuration of one example. Furthermore, it is possible to add, delete, or replace part of the configuration of each example with other configurations. [Explanation of symbols]

[0081] 101 Samples 102 sample cups 103 Sample Disc 104 Reagents 105 Reagent Bottle 106 Reagent Disks 107 Reaction Solution 108 reaction cells 109 Reaction Disc 110 Sample dispensing mechanism 111 Reagent dispensing mechanism 112 Solution stirring section 113 Absorbance measurement section 114 Cleaning section 115 Constant temperature fluid 201 Control Unit 202 Light intensity measurement circuit 203 Data Processing Unit 2031 processor 2032 Main memory 2033 Auxiliary storage unit 2033a Historical Data 2033b State determination program 2033c Replacement Timing Prediction Program 2034 Input / Output Interface 204 Input section 205 Output section 301 LED 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

Claims

1. an LED light source that irradiates light onto a liquid in a container that contains the liquid to be analyzed; a photodetector that detects light emitted from the liquid by irradiating the liquid with light using the LED light source; a data processing unit that executes a process for determining a state of the LED light source based on (i) a maximum light intensity during a period from when the LED light source is turned on until a predetermined time has elapsed until the light intensity from the LED light source is stabilized, (ii) a time period until the maximum light intensity is reached, or (iii) a rate of change of the maximum light intensity with respect to the power-on time of the LED light source; An analytical device comprising:

2. In claim 1, The data processing unit further performs a process to predict the replacement timing of the LED light source based on the correlation between the maximum light intensity and the energizing time of the LED light source, as an analytical device.

3. In claim 2, The process of predicting the replacement time of the LED light source includes: a process of measuring the maximum light amount for each power-on time of the LED light source; A process of deriving an approximate straight line from the maximum light amount for each power-on time of the LED light source; a process of predicting a replacement time for the LED light source based on the approximation line and a predetermined upper limit value of the maximum light amount; 12. An analytical device comprising:

4. In claim 1, The data processing unit further performs an analysis device that predicts the replacement time of the LED light source based on the correlation between the time it takes to reach the maximum light intensity and the energizing time of the LED light source.

5. In claim 4, The process of predicting the replacement time of the LED light source includes: a process of measuring the time it takes for the LED light source to reach the maximum light amount for each power-on time of the LED light source; A process of deriving an approximate straight line from the time it takes for the LED light source to reach the maximum light amount for each power-on time of the LED light source; a process of predicting when to replace the LED light source based on the approximation line and a predetermined upper limit value of the time until the maximum light amount is reached; 12. An analytical device comprising:

6. In claim 1, The LED light source has a light-emitting chip and a phosphor, and emits light in a wide wavelength range including a wavelength range from 370 nm to 800 nm.

7. In claim 1, The photodetector is capable of measuring the amount of light of a plurality of wavelengths, The wavelength used to measure the maximum light intensity is the wavelength closest to the wavelength of the light-emitting chip included in the LED light source.

8. In claim 1, An analyzer in which, with the light intensity after the predetermined time has elapsed since the LED light source was turned on being defined as 100%, and the definition of light intensity stability is that the amount of light intensity fluctuation is within 100 ± 0.2%, the maximum light intensity is the largest value of the light intensity detected within the time until the definition of light intensity stability is satisfied.

9. In claim 1, The data processing unit further calculating correlation data between environmental fluctuations in environmental data including the temperature and humidity of the LED light source and fluctuations in the amount of light of the LED light source; a process of correcting the light intensity data of the LED light source based on the correlation data to generate an approximate straight line; a process of predicting when to replace the LED light source based on the approximation line and a predetermined upper limit value of the time until the maximum light amount is reached; Perform the analysis on the device.

10. 1. A method for determining a state of an LED light source included in an analysis device, comprising: activating the analyzer and turning on the LED light source; measuring the light amount of the LED light source by a measurement unit; The computer calculates the maximum light output of the LED light source during the period from when the LED light source is turned on until a predetermined time has elapsed, and until the light output from the LED light source stabilizes. The computer determines the state of the LED light source based on (i) the maximum light intensity, (ii) the time to reach the maximum light intensity, or (iii) the rate of change of the maximum light intensity with respect to the power-on time of the LED light source. An LED light source state determination method, comprising:

11. In claim 10, further comprising: An LED light source status determination method, which includes predicting the replacement time of the LED light source based on the correlation between the maximum light intensity and the energizing time of the LED light source using the computer.

12. In claim 11, Predicting the replacement time for the aforementioned LED light source is: measuring the maximum light amount for each power-on time of the LED light source; deriving an approximate straight line from the maximum light amount for each power-on time of the LED light source; predicting a replacement time for the LED light source based on the approximate straight line and a predetermined upper limit value of the maximum light amount; An LED light source state determination method, comprising:

13. In claim 10, further comprising: An LED light source status determination method, which includes predicting the replacement time of the LED light source based on the correlation between the time it takes to reach the maximum light intensity and the power-on time of the LED light source, using the aforementioned computer.

14. In claim 13, Predicting the replacement time for the aforementioned LED light source is: measuring the time it takes for the LED light source to reach the maximum light amount for each power-on time; Deriving an approximate straight line from the time it takes for the LED light source to reach the maximum light amount for each power-on time of the LED light source; predicting a replacement time for the LED light source based on the approximate straight line and a predetermined upper limit value of the time required for the maximum light amount to be reached; An LED light source state determination method, comprising:

15. In claim 10, The LED light source comprises a light-emitting chip and a phosphor, and emits light with a broadband wavelength including the wavelength range from 370 nm to 800 nm. This is an LED light source state determination method.

16. In claim 10, a method for determining the state of an LED light source, wherein the light amount after the predetermined time has elapsed since the LED light source was turned on is defined as 100%, and a stable light amount is defined as a fluctuation in the light amount being within 100±0.2%, and the maximum light amount is the largest value of the light amount detected within the time until the definition of stable light amount is met.

17. In claim 10, further comprising: calculating correlation data between environmental fluctuations in environmental data including the temperature and humidity of the LED light source and fluctuations in the amount of light of the LED light source; correcting the light intensity data of the LED light source based on the correlation data to generate an approximate straight line; predicting a replacement time for the LED light source based on the approximate straight line and a predetermined upper limit value of the maximum light amount; An LED light source state determination method, comprising:

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