Spectroscopic analyzer and spectroscopic analyzing method

Abstract

To provide a spectroscopic analyzer which can more accurately analyze optical characteristics of a measurement target, with the influence of an observation window in consideration.SOLUTION: A spectroscopic analyzer 1 according to the present disclosure includes: an irradiation unit 10 for irradiating a measurement target with irradiation light; a light reception unit 40 for receiving reflected light from the measurement target based on the irradiation light; and a control unit 80 for analyzing the optical characteristics of the measurement target on the basis of the reflected light. The control unit 80 acquires environmental information of a measurement environment including an observation window W for guiding irradiation light to the measurement target and corrects a parameter showing optical characteristics according to the environmental information.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a spectroscopic analysis device and a spectroscopic analysis method. [Background technology]

[0002] Conventionally, there are known techniques for analyzing the optical characteristics of a measurement target. For example, Patent Document 1 discloses a reflectance calibration method for a reflectometer or a reflection densitometer, which aims to achieve high-precision measurement in a short time without stabilizing the irradiation output by feedback control, and does not lead to an increase in cost or size of the measurement device due to the stabilization of the irradiation output. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5540354 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional technology, an optical system is assumed in which light from a light source is directly irradiated onto the object to be measured, and when analyzing the optical characteristics of the object to be measured, the influence of an observation window used to guide the irradiated light to the object to be measured is not taken into consideration.

[0005] An object of the present disclosure is to provide a spectroscopic analysis device and a spectroscopic analysis method that can more accurately analyze the optical characteristics of a measurement target by taking into account the influence of an observation window. [Means for solving the problem]

[0006] In some embodiments, a spectroscopic analysis device includes an irradiation unit that irradiates an object to be measured with irradiation light, a light receiving unit that receives reflected light from the object to be measured based on the irradiation light, and a control unit that analyzes optical characteristics of the object to be measured based on the reflected light, and the control unit acquires environmental information of a measurement environment including an observation window that directs the irradiation light to the object to be measured, and corrects parameters indicating the optical characteristics in accordance with the environmental information.

[0007] This allows the spectroscopic analysis device to more accurately analyze the optical characteristics of the object to be measured by taking into account the influence of the observation window. The spectroscopic analysis device acquires environmental information of the measurement environment including the observation window that guides irradiated light to the object to be measured, and corrects the parameters indicating the optical characteristics according to the environmental information, thereby obtaining the parameters indicating the optical characteristics of the object to be measured while eliminating the influence of the observation window. The spectroscopic analysis device can correct the parameters indicating the optical characteristics of the object to the correct values ​​even if the reference substance and the object to be measured are measured at different positions.

[0008] In one embodiment, the control unit may construct a conversion model for correcting the parameters in the measurement environment to the parameters in a reference environment not passing through the observation window.

[0009] This allows the spectroscopic analyzer to convert the parameters indicating the optical properties of the object to correct values ​​even if the reference material and the object are measured at different positions. As a result, for example, conversion from the light reflectance obtained as the optical property to another physical quantity can be performed accurately. For example, absorbance conversion and Kubelka-Munk conversion can be performed accurately.

[0010] In one embodiment of the spectroscopic analysis device, the control unit may construct the conversion model using at least one reference substance. This allows the spectroscopic analysis device to improve the accuracy of correction of parameters indicating optical characteristics of the object to be measured using the conversion model. The spectroscopic analysis device can accurately correct parameters indicating optical characteristics of the object to be measured obtained under a measurement environment using parameters indicating optical characteristics under a reference environment.

[0011] In one embodiment, the control unit may construct the conversion model using three or more of the reference substances having different optical properties.

[0012] This allows the spectroscopic analysis device to correct nonlinear relationships with optical characteristics when correcting parameters indicating optical characteristics of the object to be measured using the conversion model. Therefore, the spectroscopic analysis device can improve the accuracy of correction of parameters indicating optical characteristics of the object to be measured. For example, when optical characteristics in the reference environment have nonlinearity with respect to optical characteristics in the measurement environment, increasing the number of reference materials is expected to improve the accuracy of correction of parameters indicating optical characteristics of the object to be measured. By measuring multiple reference materials having reflectances of various values ​​over a wide range, the accuracy of the constructed conversion model is improved.

[0013] In one embodiment, the control unit may construct the conversion model as a regression model using the parameters of the reference material in the measurement environment as explanatory variables and the parameters of the reference material in the reference environment as objective variables, thereby enabling the spectroscopic analysis device to easily construct a conversion model having a function of converting parameters indicating optical characteristics of the measured object in the measurement environment into parameters indicating optical characteristics of the measured object in the reference environment.

[0014] In one embodiment, the control unit may determine a correction coefficient according to the environmental information in constructing the conversion model, thereby enabling the spectroscopic analysis device to perform a correction process for converting parameters indicating optical characteristics of the object to be measured in the measurement environment into parameters indicating optical characteristics of the object to be measured in a reference environment using a simpler arithmetic expression.

[0015] In one embodiment of the spectroscopic analysis device, the control unit may correct the parameters of the object to be measured by referring to the conversion model associated with the observation window from among the conversion models constructed for each type of observation window.

[0016] This allows the spectroscopic analyzer to more accurately correct the parameters indicating the optical characteristics of the object to be measured in accordance with the observation window being used in real time when measuring the optical characteristics of the object to be measured. The spectroscopic analyzer can more accurately correct the parameters indicating the optical characteristics of the object to be measured by using an optimal conversion model according to the observation window currently being used.

[0017] In one embodiment of the spectroscopic analysis device, when evaluating the conversion model, the control unit may notify a user to update the conversion model if it determines that the evaluation index of the conversion model has reached a threshold value.

[0018] This allows the spectroscopic analysis device to prompt the user to reconstruct the conversion model when, for example, the parameters indicating the corrected optical characteristics of the object being measured still show abnormal values ​​and the conversion model does not function accurately. The user can also cause the spectroscopic analysis device to re-execute a series of processes related to the construction of the conversion model so as to update a low-precision conversion model to a high-precision conversion model.

[0019] In one embodiment, the control unit may execute a process of updating the conversion model, thereby enabling the spectroscopic analysis device to maintain good accuracy of the conversion model.

[0020] A spectroscopic analysis method according to some embodiments includes the steps of irradiating an object to be measured with irradiation light, receiving reflected light from the object to be measured based on the irradiation light, and analyzing optical characteristics of the object to be measured based on the reflected light, and in the step of analyzing the optical characteristics, a parameter indicating the optical characteristics is corrected in accordance with environmental information of a measurement environment including an observation window through which the irradiation light is guided to the object to be measured.

[0021] This allows the spectroscopic analysis device performing the spectroscopic analysis method to more accurately analyze the optical characteristics of the object being measured by taking into account the influence of the observation window. The spectroscopic analysis device acquires environmental information of the measurement environment including the observation window that guides irradiated light to the object being measured, and corrects the parameters indicating the optical characteristics according to the environmental information, thereby obtaining the parameters indicating the optical characteristics of the object being measured while eliminating the influence of the observation window. The spectroscopic analysis device can correct the parameters indicating the optical characteristics of the object being measured to the correct values ​​even if the reference substance and the object being measured are measured at different positions. Effect of the Invention

[0022] According to the present disclosure, it is possible to provide a spectroscopic analysis device and a spectroscopic analysis method that can more accurately analyze the optical characteristics of an object to be measured by taking into account the influence of an observation window. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a configuration of a spectroscopic analysis device according to an embodiment of the present disclosure. [Diagram 2] 4 is a flowchart illustrating a first example of the operation of the spectroscopic analysis apparatus of FIG. [Diagram 3] 13 is a flowchart illustrating a second example of the operation of the spectroscopic analysis apparatus of FIG. [Figure 4] 13 is a flowchart illustrating a third example of the operation of the spectroscopic analysis apparatus of FIG. [Diagram 5] 13 is a flowchart illustrating a fourth example of the operation of the spectroscopic analysis apparatus of FIG. [Figure 6] FIG. 2 is a schematic diagram showing an example of optical characteristics of a reference material. [Figure 7] 4 is a schematic diagram showing an example of optical characteristics of an object to be measured; FIG. [Figure 8] FIG. 2 is a schematic diagram showing an example of absorbance of a measurement target; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The background and problems of the prior art will now be described in more detail.

[0025] In the method for measuring reflectance and reflection density with a calibration function described in Patent Document 1, two types of calibration reflectance reference plates with known reflectance are used. The IS characteristics of the reflected light amount sensor output value S corresponding to the irradiated light amount I for each are measured in advance. The relationship between the a, b values ​​of the relational expression S=aR+b and the fluctuation factors is grasped, and the Ia, b characteristics and Sa, b characteristics, which are the causal relationships, are stored in memory. During calibration, the irradiated light amount I0 at that time is detected, and the accurate a, b values ​​at the time of calibration based on the two types of calibration reflectance reference plates are identified from the value and the stored causal relationship. This establishes the relational expression S=aR+b.

[0026] Next, the reflected light amount sensor output value S of the measurement target is measured. The reflectance R is calculated from the formula R=S / ab / a. Alternatively, the reflectance R value is used to calculate the reflection density D=-log 10 R is calculated.

[0027] However, the conventional technology described in Patent Document 1 assumes an optical system in which the light from the light source is directly irradiated onto the object to be measured. In the conventional technology, when analyzing the optical characteristics of the object to be measured, the influence of the observation window for guiding the light from the light source to the object to be measured placed inside the sample chamber is not taken into consideration. In addition, it does not assume a case in which a different observation window is used and the measurement environment, such as the material and thickness of the observation window, is changed.

[0028] In the above conventional technology, a linear relationship S=aR+b holds between the reflectance R and the reflected light amount sensor output value S, but in cases where it is necessary to correct a nonlinear relationship with respect to the reflectance R, it is necessary to use three or more types of reflectance reference plates. In addition, in the above conventional technology, the correction formula does not take into account the wavelength dependency of light.

[0029] An embodiment of the present disclosure will be mainly described below with reference to the accompanying drawings.

[0030] 1 is a schematic diagram showing an example of the configuration of a spectroscopic analysis device 1 according to an embodiment of the present disclosure. An example of the configuration and functions of the spectroscopic analysis device 1 will be mainly described with reference to FIG.

[0031] A spectroscopic analysis device 1 according to one embodiment analyzes optical characteristics of a measurement target placed inside a sample chamber S. More specifically, the spectroscopic analysis device 1 irradiates the measurement target with irradiation light through an observation window W installed in the sample chamber S. The spectroscopic analysis device 1 receives reflected light from the measurement target based on the irradiated light. The spectroscopic analysis device 1 analyzes the optical characteristics of the measurement target based on the received reflected light.

[0032] In the present disclosure, the "sample chamber S" includes, for example, any space having a function of storing or transporting a measurement target. The sample chamber S is composed of a tank, piping, and the like. The "observation window W" includes, for example, any window having a function of transmitting light at a wavelength of irradiation light used for the spectroscopic analysis device 1 to optically analyze the optical characteristics of the measurement target placed inside the sample chamber S. The observation window W is formed of a material such as acrylic resin, glass, sapphire, and diamond. The observation window W may have a thickness of 10 mm or more in order to provide sufficiently high impact resistance and pressure resistance.

[0033] The "measurement target" includes any object such as a solid, liquid, and slurry. The measurement target includes, for example, an object that generates diffuse reflection when the spectroscopic analysis device 1 analyzes the optical characteristics of the measurement target using a diffuse reflectance method. The "optical characteristics" include the wavelength dependency of the reflectance of light, and the like. As an example, the spectroscopic analysis device 1 analyzes the reflectance spectrum of light at the measurement target based on the diffuse reflectance method.

[0034] The spectroscopic analysis device 1 has an irradiation section 10, a light guiding section 20, a light collecting section 30, a light receiving section 40, a storage section 50, an input section 60, an output section 70, and a control section 80.

[0035] The irradiation unit 10 has a light source such as a lamp, a light emitting diode (LED), and a semiconductor laser. The lamp includes a halogen lamp, a tungsten lamp, a xenon lamp, and the like. The irradiation unit 10 irradiates the measurement object with irradiation light having a wavelength that matches the optical characteristics of the measurement object to be analyzed using the spectroscopic analysis device 1. The wavelength of the irradiation light irradiated by the irradiation unit 10 includes, for example, a wavelength at which the irradiation light is reflected by the measurement object. The wavelength of the irradiation light includes, for example, an ultraviolet region, a visible region, a near-infrared region, and other infrared regions.

[0036] The light guiding unit 20 includes any optical element for guiding light. The optical element includes an optical fiber, an optical coupler, a mirror, and the like. The light guiding unit 20 guides the irradiation light irradiated from the light source of the irradiation unit 10 to the light collecting unit 30. The light guiding unit 20 guides the irradiation light to the object to be measured placed inside the sample chamber S through the light collecting unit 30 and the observation window W. The light guiding unit 20 receives the reflected light from the object to be measured placed inside the sample chamber S through the observation window W and the light collecting unit 30. The light guiding unit 20 guides the received reflected light from the object to be measured to the light receiving unit 40. The light guiding unit 20 has a function of guiding the irradiation light from the irradiation unit 10 to the object to be measured and a function of guiding the reflected light from the object to be measured to the light receiving unit 40.

[0037] The light collecting unit 30 includes any optical element for collecting light. The optical element includes an optical lens, an integrating sphere, and the like. The light collecting unit 30 collects the irradiation light from the irradiation unit 10 guided by the light guiding unit 20, and efficiently irradiates the measured object placed inside the sample chamber S with the light. The light collecting unit 30 efficiently collects the reflected light from the measured object, which is emitted from the sample chamber S through the observation window W, into the light guiding unit 20.

[0038] The light receiving unit 40 has a photodetector including a light receiving element such as a photodiode. The light receiving unit 40 receives reflected light based on the irradiated light irradiated to the object to be measured by the irradiating unit 10, and the reflected light indicates the optical characteristics of the object to be measured. The photodetector of the light receiving unit 40 receives the reflected light from the object to be measured guided by the light collecting unit 30 and the light guiding unit 20, converts it into an electrical signal, and outputs it to the control unit 80 or the like. The wavelength band that can be received by the photodetector of the light receiving unit 40 includes the wavelength band of the reflected light. The photodetector of the light receiving unit 40 has detection sensitivity at the wavelength of the reflected light. The light receiving unit 40 has a function of detecting the intensity of the reflected light. In addition to this, the light receiving unit 40 may further have a spectroscopic function such as a diffraction grating, an interferometer, and a filter.

[0039] The storage unit 50 includes storage devices such as a hard disk drive (HDD), a solid state drive (SSD), an electrically erasable programmable read-only memory (EEPROM), a read-only memory (ROM), and a random access memory (RAM). The storage unit 50 stores information necessary to realize the operation of the spectroscopic analysis device 1. The storage unit 50 stores information obtained by the operation of the spectroscopic analysis device 1. For example, the storage unit 50 stores system programs, application programs, and various data acquired by any means such as communication.

[0040] The storage unit 50 may function as a main storage device, an auxiliary storage device, or a cache memory. The storage unit 50 is not limited to being built into the spectroscopic analysis device 1, and may include an external storage device connected via a digital input / output port such as a Universal Serial Bus (USB).

[0041] The input unit 60 includes one or more input interfaces that detect user input and acquire input information based on the user's operation. The input interfaces include physical keys, capacitive keys, a touch screen that is integrated with the display of the output unit 70, an imaging module such as a camera, and a microphone that accepts voice input.

[0042] The output unit 70 includes one or more output interfaces that output information to notify the user. The output interfaces include a display that outputs information as an image, a speaker that outputs information as sound, and a vibrator that outputs information as vibration. The display includes an LCD (Liquid Crystal Display) and an organic EL (Electro Luminescence) display.

[0043] The control unit 80 includes one or more processors. In the present disclosure, a "processor" refers to, but is not limited to, a general-purpose processor or a dedicated processor specialized for a specific process. The control unit 80 includes, for example, a CPU (Central Processing Unit). The control unit 80 is communicably connected to each component constituting the spectroscopic analysis device 1 and controls the operation of the spectroscopic analysis device 1 as a whole. The control unit 80 analyzes the optical characteristics of the object to be measured based on the reflected light received by the light receiving unit 40. In addition to such analysis processing, the control unit 80 executes various calculation processing such as correction processing of parameters indicating optical characteristics described later.

[0044] Fig. 2 is a flowchart illustrating a first example of the operation of the spectroscopic analysis device 1 of Fig. 1. An example of a spectroscopic analysis method executed by the spectroscopic analysis device 1 of Fig. 1 will be mainly described with reference to Fig. 2. The flowchart shown in Fig. 2 illustrates an example of a basic process flow when the control unit 80 of the spectroscopic analysis device 1 analyzes the optical characteristics of a measurement target.

[0045] In step S101, the control unit 80 of the spectroscopic analysis device 1 acquires environmental information of the measurement environment including the observation window W that guides the irradiation light from the irradiation unit 10 from the outside of the sample chamber S to the object to be measured inside. For example, the control unit 80 acquires the environmental information as input information input by a user using the input unit 60 of the spectroscopic analysis device 1.

[0046] In the present disclosure, the "environmental information" includes the type of the observation window W. Regarding the types of the observation window W, for example, the observation windows W having different elements such as surface roughness, thickness, and components are defined as different types. For example, the observation windows W manufactured by the same manufacturer using the same manufacturing method and numbered by an operator as 1, 2, etc. are called types. In addition, the environmental information may include the focal length of the light collecting unit 30, the wavelength of the irradiation light irradiated from the irradiation unit 10, and the measurement position where the object to be measured is placed inside the sample chamber S. The "measurement environment" includes, for example, the inside of the sample chamber S where the object to be measured is placed and the surrounding environment when the spectroscopic analysis device 1 tries to analyze the optical characteristics of the object to be measured.

[0047] In step S102, the control unit 80 of the spectroscopic analysis device 1 controls the irradiating unit 10 so that the irradiating unit 10 irradiates the object to be measured with irradiation light.

[0048] In step S103, the control unit 80 of the spectroscopic analysis device 1 causes the light receiving unit 40 to receive reflected light that is based on the irradiated light irradiated in step S102 and indicates the optical characteristics of the object to be measured.

[0049] In step S104, the control unit 80 of the spectroscopic analyzer 1 analyzes the optical characteristics of the object to be measured based on the reflected light received in step S103. In the step of analyzing the optical characteristics in step S104, the control unit 80 corrects parameters indicating the optical characteristics of the object to be measured according to the environmental information acquired in step S101. For example, the control unit 80 corrects parameters indicating the optical characteristics of the object to be measured actually measured in the measurement environment to parameters indicating the optical characteristics of the object to be measured in a reference environment not passing through the observation window W, using a conversion model described later with reference to FIG. 3. In the present disclosure, the "reference environment" includes, for example, an environment outside the sample chamber S that is not affected by the measurement environment. The "parameters indicating the optical characteristics" include at least one of the values ​​of the reflectance or absorbance of light for each wavelength, the reflected light power, and the like. The "reflected light power" includes, for example, the power of the light after the light is reflected by a predetermined object.

[0050] Fig. 3 is a flowchart for explaining a second example of the operation of the spectroscopic analysis device 1 of Fig. 1. The flowchart shown in Fig. 3 shows an example of a process flow when a conversion model used in the process of step S104 of Fig. 2 is constructed in advance before analyzing the optical characteristics of the object to be measured.

[0051] In step S201, the control unit 80 of the spectroscopic analysis device 1 uses the light receiving unit 40 to measure the first reflected light power P1 at the reference material located at the reference position.

[0052] In the present disclosure, the "reference position" includes, for example, a predetermined position in a reference environment. As shown in Fig. 1, the reference position includes, for example, a position L1 between the light collecting unit 30 of the spectroscopic analysis device 1 and the observation window W, and a position L2 on the outer surface of the observation window W located outside the sample chamber S. The "reference material" includes any material having a light reflectance of approximately 100%. The reference material includes a standard white plate, barium sulfate, a gold mirror, and the like that have the function of reflecting light with a high reflectance.

[0053] For example, the reference substance may be attached to the tip of the observation window W side of a cylindrical outer frame covering the optical path in the spectroscopic analysis device 1 from the tip of the light guiding unit 20 to the light collecting unit 30 and placed at position L1, or may be attached to any other optical mount and placed at position L1. The reference substance may be placed at position L2 by being fixed to the outer surface of the observation window W by any method.

[0054] In step S202, the control unit 80 of the spectroscopic analysis device 1 measures the second reflected light power P2 at the reference material at the reference position using the light receiving unit 40. In this disclosure, the "reference material" includes a material that has a function of reflecting light at an arbitrary reflectance. The reference material may include a solid material such as a standard reflector, or may include a fluid material such as a liquid.

[0055] The control unit 80 measures the second reflected light power P2 for each of a plurality of reference materials having different optical characteristics. The plurality of reference materials include materials having various reflectivities, from materials that reflect light with a relatively high reflectivity to materials that hardly reflect light, so as to cover the range of reflectivities that the measurement target can have. A conceivable method for measuring the second reflected light power P2 for a plurality of reference materials is to place a plurality of reference materials having different reflectivities on a disk and rotate the disk to change the reference material located on the optical path.

[0056] In step S203, the control unit 80 of the spectroscopic analysis device 1 uses the light receiving unit 40 to measure the third reflected light power P3 of the reference material located at the measurement position where the measured object is placed inside the sample chamber S. When measuring the first reflected light power P1, the second reflected light power P2, and the third reflected light power P3, the control unit 80 adjusts the output of the irradiating unit 10 so that the light power of the irradiation light irradiated from the irradiating unit 10 immediately after exiting the light guiding unit 20 is all the same. In step S203, the same reference materials as those used in step S202 are used.

[0057] The process in step S203 is performed using the sample chamber S and the observation window W before the measured object is stored or transported, or is performed using a simulated measurement environment that mimics the arrangement of the sample chamber S and the observation window W when the measured object is stored or transported. For example, the reference substance may be placed at the measurement position as a solid such as a standard reflector, by being pressed against the observation window W inside the sample chamber S, or by being fixed by any method inside the sample chamber S at a distance from the observation window W. Alternatively, the reference substance may be placed at the measurement position as a fluid such as a liquid, by filling the inside of the sample chamber S.

[0058] The process in step S203 is performed according to the type of observation window W. That is, when analysis of the optical characteristics of the object to be measured is performed for a plurality of observation windows W having characteristics different from each other, the process in step S203 is performed for each of the plurality of observation windows W.

[0059] In step S204, the control unit 80 of the spectroscopic analysis device 1 constructs a conversion model for correcting parameters indicating the optical characteristics of the object to be measured in the measurement environment to parameters indicating the optical characteristics of the object to be measured in a reference environment not through the observation window W.

[0060] For example, the control unit 80 constructs a conversion model using a plurality of reference substances having different optical properties used in steps S202 and S203. The control unit 80 constructs a conversion model using, for example, three or more reference substances. The control unit 80 constructs the conversion model as a regression model, using parameters indicating the optical properties of the reference substances in the measurement environment as explanatory variables and parameters indicating the optical properties of the reference substances in the reference environment as objective variables.

[0061] For example, the control unit 80 calculates the reflectance P2 / P1 of the reference material at the reference position by dividing the second reflected light power P2 by the first reflected light power P1. The control unit 80 calculates the reflectance P3 / P1 of the reference material at the measurement position by dividing the third reflected light power P3 by the first reflected light power P1. The control unit 80 constructs a conversion model for converting the reflectance P3 / P1 to the reflectance P2 / P1. The control unit 80 constructs a conversion model such as a linear regression model and a nonlinear regression model using the reflectance P3 / P1 as an explanatory variable and the reflectance P2 / P1 as a target variable.

[0062] The control unit 80 determines a correction coefficient according to the environmental information in constructing the conversion model. That is, similar to the process in step S203, the control unit 80 constructs a conversion model for each of the multiple observation windows W and determines a correction coefficient according to the observation window W.

[0063] In step S205, the control unit 80 of the spectroscopic analysis device 1 stores the conversion model constructed in step S204 in the storage unit 50. The control unit 80 stores in the storage unit 50 a database generated by associating the conversion models constructed for each type of observation window W with the corresponding observation windows W.

[0064] Fig. 4 is a flowchart for explaining a third example of the operation of the spectroscopic analysis device 1 of Fig. 1. The flowchart shown in Fig. 4 shows an example in which the process in step S104 of the flowchart shown in Fig. 2 is further subdivided.

[0065] In step S301, in a step of analyzing the optical characteristics of the object to be measured, the control unit 80 of the spectroscopic analysis device 1 refers to a database related to the conversion models stored in the storage unit 50 in step S205 of Fig. 3. For example, the control unit 80 refers to the conversion model associated with the observation window W specified by the user as environmental information using the input unit 60 in step S101 of Fig. 2, from among the conversion models constructed for each type of observation window W in step S204 of Fig. 3.

[0066] In step S302, the control unit 80 of the spectroscopic analysis device 1 corrects the parameters indicating the optical characteristics of the object to be measured using the conversion model referred to in step S301. For example, the control unit 80 uses the same measurement environment as the measurement environment used in step S203 of Fig. 3 to measure the fourth reflected light power P4 of the object to be measured at the measurement position using the light receiving unit 40. The control unit 80 calculates the reflectance P4 / P1 of the object to be measured at the measurement position by dividing the fourth reflected light power P4 by the first reflected light power P1. The first reflected light power P1 used here is not measured in the construction process of the conversion model shown in the flowchart of Fig. 3, but is measured using a reference material at a reference position when the control unit 80 of the spectroscopic analysis device 1 analyzes the optical characteristics of the object to be measured.

[0067] The control unit 80 applies the conversion model referred to in step S301 to the reflectance P4 / P1, thereby correcting it to a parameter indicating the optical characteristics of the object to be measured in the reference environment not through the observation window W. For example, the control unit 80 applies a correction coefficient according to the observation window W to the reflectance P4 / P1, thereby correcting it to a parameter indicating the optical characteristics of the object to be measured in the reference environment not through the observation window W.

[0068] Fig. 5 is a flowchart illustrating a fourth example of the operation of the spectroscopic analysis device 1 of Fig. 1. The flowchart shown in Fig. 5 shows the flow of processing related to evaluation of the conversion model stored in the storage unit 50 in step S205 of Fig. 3.

[0069] In step S401, the control unit 80 of the spectroscopic analysis device 1 determines whether or not the evaluation index of the conversion model stored in the storage unit 50 in step S205 of Fig. 3 has reached a threshold value. If the control unit 80 determines that the evaluation index has reached the threshold value, it executes the process of step S402. If the control unit 80 determines that the evaluation index has not reached the threshold value, it ends the process.

[0070] In the present disclosure, the "evaluation index" may be, for example, MSE (Mean Squared Error), RMSE (Root Mean Squared Error), MAE (Mean Absolute Error), and R 2 The conversion model may include an index for evaluating a regression model such as the above, or may include the parameters themselves indicating the optical characteristics of the object under measurement after being corrected by the conversion model.

[0071] In step S402, when the control unit 80 of the spectroscopic analysis device 1 determines that the evaluation index has reached the threshold value in step S401, the control unit 80 notifies the user to update the conversion model. For example, the control unit 80 notifies the user using the output unit 70 to update a conversion model with a low evaluation based on the evaluation index and low accuracy to a conversion model with high accuracy. When the user confirms the notification output from the output unit 70, the user causes the spectroscopic analysis device 1 to execute again a series of processes related to the construction of the conversion model according to the flowchart shown in FIG. 3. As a result, the control unit 80 of the spectroscopic analysis device 1 executes a process of updating the conversion model.

[0072] An example of the optical characteristics of a reference material obtained when constructing a conversion model according to the flowchart shown in Fig. 3 will be described below with reference to Fig. 6 to Fig. 8. Similarly, an example of the optical characteristics of a measured object before and after correction by a conversion model and the corresponding absorbance of the measured object will be described below with reference to the flowchart shown in Fig. 4. In the following, the wavelength dependency of the reflectance of light will be shown as an example of the optical characteristics.

[0073] FIG. 6 is a schematic diagram showing an example of optical characteristics of a reference material. FIG. 6 shows an example of optical characteristics of a reference material obtained when constructing a conversion model according to the flowchart shown in FIG. 3. FIG. 6(a) shows the wavelength dependency of light reflectance (P2 / P1×100) at a reference position for a plurality of reference materials. Numbers 1 to 7 are assigned to the graphs corresponding to the plurality of reference materials. FIG. 6(b) shows the wavelength dependency of light reflectance (P3 / P1×100) at a measurement position for a plurality of reference materials. Numbers 1 to 7 are similarly assigned to the graphs corresponding to FIG. 6(a).

[0074] Fig. 7 is a schematic diagram showing an example of the optical characteristics of the object to be measured. Fig. 7 shows an example of the optical characteristics of the object to be measured before and after correction by the conversion model according to the flowchart shown in Fig. 4. Fig. 7(a) shows the wavelength dependency of the light reflectance (P4 / P1×100) before correction by the conversion model. Fig. 7(b) shows the wavelength dependency of the light reflectance after correction by the conversion model.

[0075] Fig. 8 is a schematic diagram showing an example of absorbance of a measurement target. Fig. 8(a) shows an absorbance spectrum corresponding to the reflectance spectrum of Fig. 7(a). Fig. 8(b) shows an absorbance spectrum corresponding to the reflectance spectrum of Fig. 7(b).

[0076] As described above, the reflectance of light is calculated by dividing the fourth reflected light power P4 at the object to be measured by the first reflected light power P1 at the reference material with a known reflectance. In this case, if the reference material and the object to be measured are placed at the same positions, the same environment is obtained. Therefore, a correct value is obtained as the reflectance of light.

[0077] However, once the process has started, it is not easy to place the reference material at the same position as the object to be measured, as this may require line cleaning and disassembly. Therefore, for periodic calibration, it is necessary to measure the reference material at a position different from the object to be measured. For example, it is assumed that the object to be measured is inside the sample chamber S, and the reference material is at position L1 outside the sample chamber S.

[0078] At this time, the reflectance of the light at the object to be measured may not show a correct value due to differences in the position relative to the focus of the light collecting unit 30 and the presence or absence of the observation window W. For example, as shown in FIG. 7(a), the reflectance of the light may show a value of 100% or more. As a result, the absorbance conversion and Kubelka-Munk conversion may be hindered and a correct value may not be obtained. For example, as shown in FIG. 8(a), the absorbance of the object to be measured may show a negative value. In addition, when the observation window W is changed to a different one and the measurement environment is changed, the reflectance spectrum obtained as the optical characteristic of the object to be measured also changes, so that it is not easy to compare the measured values ​​regarding the optical characteristics of the object to be measured.

[0079] As described above, the difference in the environment, including the optical path, between the measurement of the reference substance and the measurement of the object to be measured causes an abnormal value of the spectrum in the optical characteristics. Such an abnormal value is eliminated by the conversion model constructed using the reference substance according to the flowchart shown in Fig. 3. At this time, as described above, in step S203 of Fig. 3, the sample chamber S and the observation window W before the object to be measured are used, or a pseudo measurement environment that mimics the arrangement of the sample chamber S and the observation window W when the object to be measured is stored or transported is used. By correcting the difference in the environment based on the above conversion model, the correct value of the spectrum in the optical characteristics can be obtained.

[0080] For example, a plurality of reference materials having the optical characteristics shown in FIG. 6 are used to construct a conversion model. As shown in FIG. 6(a), when the optical characteristics of the reference material are measured at the same reference position as the reference material, the light reflectance shows a correct value. On the other hand, as shown in FIG. 6(b), when the optical characteristics of the reference material are measured at a measurement position different from the reference position, an abnormal value occurs for the same reason as above. The control unit 80 of the spectroscopic analysis device 1 constructs a conversion model such as a linear regression model and a nonlinear regression model using the reflectance P3 / P1 shown in FIG. 6(b) as an explanatory variable and the reflectance P2 / P1 shown in FIG. 6(a) as an objective variable.

[0081] When the parameters indicating the optical characteristics of the object to be measured as shown in (a) of Fig. 7 are corrected by the constructed conversion model, the light reflectance is 100% or less and the normal correct value is shown as shown in (b) of Fig. 7. Correspondingly, the absorbance of the object to be measured becomes positive and the normal correct value is shown as shown in (b) of Fig. 8.

[0082] According to the spectroscopic analysis device 1 of the embodiment described above, the optical characteristics of the object to be measured can be analyzed more accurately by taking into account the influence of the observation window W. The spectroscopic analysis device 1 acquires environmental information of the measurement environment including the observation window W that guides irradiated light to the object to be measured, and corrects the parameters indicating the optical characteristics in accordance with the environmental information, thereby making it possible to obtain the parameters indicating the optical characteristics of the object to be measured while eliminating the influence of the observation window W. The spectroscopic analysis device 1 can correct the parameters indicating the optical characteristics of the object to the correct values ​​even if the reference substance and the object to be measured are measured at different positions.

[0083] In addition, even when the optical characteristics of the object to be measured are measured while changing the measurement environment, such as the observation window W, the spectroscopic analysis device 1 can correct the signal values ​​obtained regarding the optical characteristics for each different measurement environment to match them with the reference environment. Therefore, the spectroscopic analysis device 1 can easily compare signal values ​​that would otherwise be difficult to compare due to different measurement environments, as if they were measured under the same reference environment.

[0084] The spectroscopic analysis device 1 constructs a conversion model for correcting parameters indicating the optical characteristics of the object to be measured in the measurement environment to parameters indicating the optical characteristics in a reference environment not passing through the observation window W. This allows the spectroscopic analysis device 1 to convert the parameters indicating the optical characteristics of the object to correct values ​​even if the reference substance and the object to be measured are measured at different positions. As a result, for example, conversion from the reflectance of light obtained as the optical characteristics to other physical quantities can be accurately performed. For example, absorbance conversion and Kubelka-Munk conversion can be accurately performed.

[0085] The spectroscopic analysis device 1 can improve the accuracy of correction of parameters indicating optical characteristics of a measured object by using the conversion model by constructing the conversion model using at least one reference substance. The spectroscopic analysis device 1 can accurately correct parameters indicating optical characteristics of a measured object obtained under a measurement environment using parameters indicating optical characteristics under a reference environment.

[0086] The spectroscopic analysis device 1 constructs a conversion model using three or more reference substances having different optical properties, and when correcting parameters indicating the optical properties of the object to be measured using the conversion model, it is possible to correct nonlinear relationships with the optical properties. This allows the spectroscopic analysis device 1 to improve the accuracy of correction of parameters indicating the optical properties of the object to be measured. For example, when the optical properties in the reference environment are nonlinear with respect to the optical properties in the measurement environment, increasing the number of reference substances is expected to improve the accuracy of correction of parameters indicating the optical properties of the object to be measured. The accuracy of the constructed conversion model is improved by measuring multiple reference substances having reflectances of various values ​​over a wide range.

[0087] The spectroscopic analysis device 1 uses parameters indicating the optical characteristics of the reference material in the measurement environment as explanatory variables and parameters indicating the optical characteristics of the reference material in the reference environment as objective variables to construct a conversion model as a regression model. This enables the spectroscopic analysis device 1 to easily construct a conversion model having a function of converting parameters indicating the optical characteristics of the measured object in the measurement environment into parameters indicating the optical characteristics of the measured object in the reference environment.

[0088] In constructing the conversion model, the spectroscopic analysis device 1 determines the correction coefficients according to the environmental information, which enables the spectroscopic analysis device 1 to execute the correction process for converting the parameters indicating the optical characteristics of the object to be measured in the measurement environment into the parameters indicating the optical characteristics of the object to be measured in the reference environment, using a simpler arithmetic expression.

[0089] The spectroscopic analysis device 1 corrects the parameters indicating the optical characteristics of the object to be measured by referring to the conversion model associated with the observation window W from among the conversion models constructed for each type of observation window W. This allows the spectroscopic analysis device 1 to more accurately correct the parameters indicating the optical characteristics of the object to be measured in accordance with the observation window W being used in real time when measuring the optical characteristics of the object to be measured. The spectroscopic analysis device 1 can more accurately correct the parameters indicating the optical characteristics of the object to be measured by using the optimal conversion model according to the observation window W currently being used.

[0090] When the spectroscopic analysis device 1 determines that the evaluation index of the conversion model has reached the threshold, it notifies the user to update the conversion model. In this way, the spectroscopic analysis device 1 can prompt the user to reconstruct the conversion model when, for example, the parameter indicating the corrected optical characteristics of the measured object still indicates an abnormal value and the conversion model does not function accurately. The user can also cause the spectroscopic analysis device 1 to re-execute a series of processes related to the construction of the conversion model so as to update a low-accuracy conversion model to a high-accuracy conversion model.

[0091] The spectroscopic analysis device 1 can maintain the accuracy of the conversion model by executing a process of updating the conversion model. In addition, since the optical characteristics include the wavelength dependency of the reflectance of light, the spectroscopic analysis device 1 can configure a correction formula that depends on the wavelength for the reflectance of light, and can improve the accuracy when correcting the parameters indicating the optical characteristics of the object to be measured.

[0092] It is obvious to those skilled in the art that the present disclosure can be realized in other specific forms other than the above-described embodiments without departing from the spirit or essential characteristics thereof. Therefore, the above description is illustrative and not limiting. The scope of the disclosure is defined by the appended claims, not by the above description. Any modifications within the scope of the equivalents of all modifications are intended to be included therein.

[0093] For example, the shape, pattern, size, arrangement, orientation, type, number, etc. of each of the above-mentioned components are not limited to the above description and the contents illustrated in the drawings. The shape, pattern, size, arrangement, orientation, type, number, etc. of each component may be configured arbitrarily as long as the function can be realized. Each component of the illustrated spectroscopic analysis device 1 is a functional concept, and the specific form of each component is not limited to that illustrated.

[0094] The functions contained in each of the above-mentioned components or steps can be rearranged so as not to cause logical inconsistencies, and multiple components or steps can be combined into one or divided.

[0095] For example, it is also possible to cause a general-purpose electronic device such as a smartphone or a computer to function as the spectroscopic analysis device 1 according to the embodiment described above. Specifically, a program describing the processing contents for realizing each function of the spectroscopic analysis device 1 according to the embodiment is stored in a memory of the electronic device, and the program is read and executed by a processor of the electronic device. Thus, the present disclosure can also be realized as a program executable by a processor.

[0096] Alternatively, the present disclosure may be realized as a non-transitory computer-readable medium storing a program executable by one or more processors to cause the spectroscopic analysis device 1 according to an embodiment to execute each function. It should be understood that these are also included within the scope of the present disclosure.

[0097] In the above embodiment, the spectroscopic analysis device 1 has been described as constructing a conversion model for correcting parameters indicating optical characteristics in a measurement environment to parameters indicating optical characteristics in a reference environment not passing through the observation window W, but is not limited to this. The spectroscopic analysis device 1 may execute a correction process for parameters indicating optical characteristics of the object to be measured by any other method other than the construction of a conversion model.

[0098] In the above embodiment, the spectroscopic analysis device 1 constructs a conversion model using a plurality of reference substances having different optical properties, but the present invention is not limited to this. The spectroscopic analysis device 1 may construct a conversion model using only one reference substance. For example, if the optical properties of the reference substance can be changed by changing a condition such as temperature, the spectroscopic analysis device 1 may change the condition to realize a plurality of different optical properties using only one reference substance.

[0099] In the above embodiment, the spectroscopic analysis device 1 constructs a conversion model using three or more reference substances having different optical properties, but the present invention is not limited to this. The spectroscopic analysis device 1 may construct a conversion model using two reference substances having different optical properties.

[0100] In the above embodiment, the spectroscopic analysis device 1 is described as constructing a conversion model as a regression model using parameters indicating optical characteristics of the reference material in the measurement environment as explanatory variables and parameters indicating optical characteristics of the reference material in the reference environment as objective variables, but is not limited thereto. The spectroscopic analysis device 1 may construct a conversion model as any other model based on machine learning, other statistical processing, or the like.

[0101] In the above embodiment, the spectroscopic analysis device 1 determines the correction coefficient according to the environmental information in constructing the conversion model, but is not limited to this. The spectroscopic analysis device 1 may execute the correction process of the parameters indicating the optical characteristics of the object to be measured based on any other correction formula different from the correction formula using the correction coefficient.

[0102] In the above embodiment, the spectroscopic analysis device 1 corrects the parameters indicating the optical characteristics of the object to be measured by referring to the conversion model associated with the observation window W from among the conversion models constructed for each type of observation window W, but is not limited to this. The spectroscopic analysis device 1 may automatically identify the observation window W by any other method and refer to the optimal conversion model instead of or in addition to the input information from the user using the input unit 60. The spectroscopic analysis device 1 may not need to generate a database in which the conversion models constructed for each type of observation window W and the corresponding observation window W are associated with each other. In this case, the spectroscopic analysis device 1 may execute the correction process of the parameters indicating the optical characteristics of the object to be measured by using the same conversion model regardless of the observation window W.

[0103] In the above embodiment, the spectroscopic analysis device 1 notifies the user to update the conversion model when it is determined that the evaluation index of the conversion model has reached the threshold value, but this is not limited to the above. The spectroscopic analysis device 1 does not need to execute such a determination process and notification process. Accordingly, the spectroscopic analysis device 1 does not need to execute a process of updating the conversion model.

[0104] In the above embodiment, the optical characteristics include the wavelength dependency of the reflectance of light, but are not limited thereto. The optical characteristics may include the reflectance of light at a specific wavelength, instead of the wavelength dependency as in the reflectance spectrum. The optical characteristics may include any other characteristics related to the absorption, transmission, scattering, etc. of light, instead of or in addition to the characteristics related to the reflection of light. For example, the optical characteristics may include the wavelength dependency of the absorptance, transmittance, and scattering coefficient of light, or may include the absorptance, transmittance, and scattering coefficient of light at a specific wavelength.

[0105] In the above embodiment, the spectroscopic analysis device 1 has been described as acquiring the environmental information as input information input by the user using the input unit 60, but is not limited thereto. The spectroscopic analysis device 1 may acquire the environmental information by any other method. For example, the spectroscopic analysis device 1 acquires the product model name of the optical probe including the light collecting unit 30 attached to the light guiding unit 20 as information input by the user using the input unit 60. The spectroscopic analysis device 1 may refer to the product information of the corresponding optical probe stored in advance in the storage unit 50 based on the acquired product model name, and acquire the environmental information based on the product information. Alternatively, the spectroscopic analysis device 1 may acquire the product information of the corresponding optical probe by any method such as communication based on the acquired product model name, and acquire the environmental information based on the product information.

[0106] In the above embodiment, the reference position has been described as including, for example, position L1 between the light collecting unit 30 and the observation window W of the spectroscopic analysis device 1 and position L2 on the outer surface of the observation window W located outside the sample chamber S, but is not limited thereto. The reference position may include any other position at which the optical path of the irradiated light in the light guiding unit 20 can be branched and a part of the irradiated light can reach.

[0107] In the above embodiment, the spectroscopic analysis device 1 executes the process of step S202 in the flowchart shown in Fig. 3, but is not limited to this. When the reflectance of light from a reference substance is known, the spectroscopic analysis device 1 may omit the process of step S202 and use the known reflectance as a response variable to construct a conversion model.

[0108] In the above embodiment, the spectroscopic analysis device 1 constructs a conversion model for converting the reflectance P3 / P1 to the reflectance P2 / P1, but is not limited to this. The spectroscopic analysis device 1 may construct a conversion model for converting the third reflected light power P3 to the second reflected light power P2.

[0109] Some of the embodiments of the present disclosure will be described below as examples. However, it should be noted that the embodiments of the present disclosure are not limited to these examples. [Appendix 1] an irradiation unit that irradiates an object to be measured with irradiation light; a light receiving unit that receives reflected light from an object to be measured based on the irradiated light; A control unit that analyzes optical characteristics of the object to be measured based on the reflected light; Equipped with the control unit acquires environmental information of a measurement environment including an observation window that guides the irradiated light to the object to be measured, and corrects a parameter indicating the optical characteristic in accordance with the environmental information. Spectroscopic analyzer. [Appendix 2] 2. The spectroscopic analyzer according to claim 1, The control unit constructs a conversion model for correcting the parameters in the measurement environment to the parameters in a reference environment not passing through the observation window. Spectroscopic analyzer. [Appendix 3] 3. The spectroscopic analyzer according to claim 2, The control unit constructs the conversion model using at least one reference substance. Spectroscopic analyzer. [Appendix 4] 4. The spectroscopic analyzer according to claim 3, The control unit constructs the conversion model using three or more reference substances having different optical properties. Spectroscopic analyzer. [Appendix 5] 5. The spectroscopic analyzer according to claim 3 or 4, the control unit uses the parameters of the reference substance in the measurement environment as explanatory variables and the parameters of the reference substance in the reference environment as objective variables, and constructs the conversion model as a regression model. Spectroscopic analyzer. [Appendix 6] 6. The spectroscopic analyzer according to claim 2, The control unit determines a correction coefficient according to the environmental information in constructing the conversion model. Spectroscopic analyzer. [Appendix 7] 7. The spectroscopic analyzer according to claim 2, the control unit corrects the parameters of the object to be measured by referring to the conversion model associated with the observation window from among the conversion models constructed for each type of the observation window. Spectroscopic analyzer. [Appendix 8] 8. The spectroscopic analyzer according to claim 2, When the control unit determines that an evaluation index of the conversion model has reached a threshold value when evaluating the conversion model, the control unit notifies a user to update the conversion model. Spectroscopic analyzer. [Appendix 9] 9. The spectroscopic analyzer according to claim 8, The control unit executes a process of updating the transformation model. Spectroscopic analyzer. [Appendix 10] A step of irradiating an object to be measured with irradiation light; receiving light reflected from the object based on the irradiated light; analyzing an optical characteristic of the object to be measured based on the reflected light; Including, In the step of analyzing the optical characteristics, a parameter indicating the optical characteristics is corrected in accordance with environmental information of a measurement environment including an observation window through which the irradiated light is guided to the object to be measured. Spectroscopic analysis method. [Explanation of symbols]

[0110] 1 Spectrometer 10 Irradiation unit 20 Light guide section 30 Light collecting section 40 Light receiving part 50 Storage section 60 Input section 70 Output section 80 Control section L1 position L2 position P1 First reflected light power P2 Second reflected light power P3 Third reflected light power P4 4th reflected light power S Sample chamber W Observation window

Claims

1. an irradiation unit that irradiates an object to be measured with irradiation light; a light receiving unit that receives reflected light from the object to be measured based on the irradiated light; A control unit that analyzes optical characteristics of the object to be measured based on the reflected light; Equipped with the control unit acquires environmental information of a measurement environment including an observation window that guides the irradiated light to the object to be measured, and corrects a parameter indicating the optical characteristic in accordance with the environmental information. Spectroscopic analyzer.

2. The spectroscopic analysis device according to claim 1 , The control unit constructs a conversion model for correcting the parameters in the measurement environment to the parameters in a reference environment not passing through the observation window. Spectroscopic analyzer.

3. The spectroscopic analysis device according to claim 2, The control unit constructs the conversion model using at least one reference substance. Spectroscopic analyzer.

4. The spectroscopic analysis device according to claim 3, The control unit constructs the conversion model using three or more reference substances having different optical properties. Spectroscopic analyzer.

5. The spectroscopic analysis device according to claim 3 or 4, the control unit uses the parameters of the reference substance in the measurement environment as explanatory variables and the parameters of the reference substance in the reference environment as objective variables, and constructs the conversion model as a regression model. Spectroscopic analyzer.

6. The spectroscopic analysis device according to any one of claims 2 to 4, The control unit determines a correction coefficient according to the environmental information in constructing the conversion model. Spectroscopic analyzer.

7. The spectroscopic analysis device according to any one of claims 2 to 4, the control unit corrects the parameters of the object to be measured by referring to the conversion model associated with the observation window from among the conversion models constructed for each type of the observation window. Spectroscopic analyzer.

8. The spectroscopic analysis device according to any one of claims 2 to 4, When the control unit determines that an evaluation index of the conversion model has reached a threshold value when evaluating the conversion model, the control unit notifies a user to update the conversion model. Spectroscopic analyzer.

9. The spectroscopic analysis device according to claim 8, The control unit executes a process of updating the transformation model. Spectroscopic analyzer.

10. A step of irradiating an object to be measured with irradiation light; receiving light reflected from the object based on the irradiated light; analyzing an optical characteristic of the object to be measured based on the reflected light; Including, In the step of analyzing the optical characteristics, a parameter indicating the optical characteristics is corrected in accordance with environmental information of a measurement environment including an observation window through which the irradiated light is guided to the object to be measured. Spectroscopic analysis method.

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