Optical physical quantity measurement device and method for manufacturing optical physical quantity measurement device

Abstract

The purpose of the present invention is to improve measurement accuracy and precision, reduce cost, and reduce device size in an optical physical quantity measurement device with which it is possible to measure two or more physical quantities. For this purpose, an optical physical quantity measurement device comprises a plurality of light-emitting units that emit light having a wavelength of at least 200 nm and less than 240 nm. The light emission output of a first light-emitting unit from among the plurality of light-emitting units at each wavelength of at least 200 nm and less than 240 nm is greater than the respective light emission outputs, at the same wavelengths, of all other light-emitting units from among the plurality of light-emitting units. Additionally, it is preferable that the light emission output of a second light-emitting unit at each wavelength of at least 200 nm and less than 240 nm is less than the respective light emission outputs, at the same wavelengths, of all other light-emitting units from among the plurality of light-emitting units.

Description

Optical physical quantity measuring device and method for manufacturing an optical physical quantity measuring device

[0001] This disclosure relates to an optical physical quantity measuring device and a method for manufacturing an optical physical quantity measuring device.

[0002] Ultraviolet light with wavelengths between 200 nm and 240 nm is absorbable by various substances such as nitrogen compounds, sulfur compounds, ozone, chlorine compounds, and organic matter. By combining it with a light-receiving unit, physical information such as the concentration and type of substance can be calculated from the amount of light attenuation (Patent Document 1). In order to obtain two or more pieces of physical information from a measurement target, a method is often used in which two or more light-emitting units with different emission wavelength ranges and two or more light-receiving units having light-receiving sensitivity in wavelength ranges corresponding to the emission wavelengths from each light-emitting unit are separately arranged (Patent Document 2). However, when preparing two or more light sources in the ultraviolet range with wavelengths between 200 nm and 240 nm, it is difficult to completely separate the emission wavelength bands of the light emitted by the two or more light sources, making it difficult to calculate two or more pieces of physical information from the measurement results.

[0003] Japanese Patent Publication No. 2017-532535, Japanese Patent Publication No. 2006-284398

[0004] This disclosure aims to enable the measurement of two or more physical quantities with high accuracy and precision, and at a lower cost, using a light-emitting unit that emits light with a wavelength of 200 nm or more and less than 240 nm.

[0005] To solve the above-mentioned problems, an optical physical quantity measuring device according to one aspect of the present disclosure includes a plurality of light-emitting units that emit light with a wavelength of 200 nm or more and less than 240 nm, wherein the light emission output of the first light-emitting unit among the plurality of light-emitting units at each wavelength of 200 nm or more and less than 240 nm is greater than the light emission output of all other light-emitting units among the plurality of light-emitting units at the same wavelength.

[0006] Furthermore, in an optical physical quantity measuring device according to another aspect of the present disclosure, there are a plurality of light-emitting units that emit light with a wavelength of at least 200 nm or more and less than 240 nm, wherein the emission output of the first light-emitting unit among the plurality of light-emitting units at each wavelength between 240 nm and 280 nm is greater than the emission output of all other light-emitting units among the plurality of light-emitting units at the same wavelength.

[0007] Furthermore, in an optical physical quantity measuring system according to another aspect of the present disclosure, the optical physical quantity measuring device comprises: a first light receiving unit that receives at least a portion of the light emitted by a first light-emitting unit; a second light receiving unit that receives at least a portion of the light emitted by at least one light-emitting unit different from the first light-emitting unit among a plurality of light-emitting units; and an acquisition unit that acquires the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit; and a calculation unit that calculates physical quantities of at least two substances based on the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit acquired by the acquisition unit.

[0008] Furthermore, in an optical physical quantity measuring system according to another aspect of the present disclosure, the optical physical quantity measuring device comprises: a first light receiving unit that receives at least a portion of the light emitted by a first light-emitting unit; a second light receiving unit that receives at least a portion of the light emitted by at least one light-emitting unit different from the first light-emitting unit among a plurality of light-emitting units; and an acquisition unit that acquires the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit; and a storage unit that stores the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit acquired by the acquisition unit.

[0009] Furthermore, in a method for manufacturing an optical physical quantity measuring device according to another aspect of the present disclosure, a plurality of light-emitting units that emit light at wavelengths of 200 nm to less than 240 nm, including the first light-emitting unit, are selected and equipped with the selected plurality of light-emitting units, such that the light emission output of the first light-emitting unit at each wavelength of 200 nm to less than 240 nm is greater than the light emission output of all other light-emitting units at the same wavelength.

[0010] Furthermore, in an inspection method for an optical physical quantity measuring device according to another aspect of the present disclosure, the optical physical quantity measuring device comprises a first light-emitting unit and a second light-emitting unit whose light-emitting output at each wavelength between 200 nm and 240 nm is smaller than the light-emitting output of the first light-emitting unit at the same wavelength, and includes: acquiring the light-emitting output of the first light-emitting unit at each wavelength between 200 nm and 240 nm; calculating and acquiring the maximum possible value of the integrated light-emitting output of the optical physical quantity measuring device at wavelengths between 200 nm and 240 nm based on the light-emitting output of the first light-emitting unit; and determining that the optical physical quantity measuring device is a good product if the maximum possible value of the light-emitting output does not exceed the permissible upper limit, which is the upper limit of the light-emitting output predetermined as a good product standard.

[0011] Furthermore, in an inspection method for an optical physical quantity measuring device according to another aspect of the present disclosure, the optical physical quantity measuring device comprises a first light-emitting unit and a second light-emitting unit whose light emission output at each wavelength between 200 nm and 240 nm is smaller than the light emission output of the first light-emitting unit at the same wavelength, the method comprising: acquiring the light emission output of the second light-emitting unit at each wavelength between 200 nm and 240 nm; calculating and acquiring a minimum luminescence possibility value, which is the smallest value that the integrated light emission output of the optical physical quantity measuring device can take in the wavelength region between 200 nm and 240 nm, based on the light emission output of the second light-emitting unit; and determining that the optical physical quantity measuring device is a good product if the minimum luminescence possibility value does not fall below an allowable lower limit value, which is a predetermined lower limit value of light emission output set as a good product standard.

[0012] According to one aspect of the present disclosure, an optical physical quantity measuring device can measure two or more physical quantities with high accuracy and precision and at low cost using a light-emitting unit that emits light with a wavelength of 200 nm or more and less than 240 nm.

[0013] This is an explanatory diagram for explaining the operation of an optical physical quantity measuring device according to an embodiment of this disclosure. This is a graph showing the emission spectra of the light-emitting diodes (LED1, LED2) of the optical physical quantity measuring device according to an embodiment of this disclosure. This is a flowchart explaining the inspection method of the ultraviolet light-emitting a conventional ultraviolet light-emitting device. This is a flowchart explaining the inspection method of a conventional ultraviolet light-emitting device. This is an explanatory diagram for explaining an example of a measurement method of an optical physical quantity measuring device according to an embodiment of this disclosure.

[0014] The optical physical quantity measuring device of this disclosure will be described below through embodiments of the invention, but the following embodiments are not intended to limit the invention as defined in the claims. Furthermore, not all combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0015] 1. First Embodiment (1) Basic Structure of Optical Physical Quantity Measuring Device The optical physical quantity measuring device according to the first embodiment of this disclosure will be described below. The optical physical quantity measuring device according to this embodiment is an optical physical quantity measuring device equipped with a plurality of light-emitting units that emit ultraviolet light with a wavelength of 200 nm or more and less than 240 nm to a target for ultraviolet irradiation. The optical physical quantity measuring device may be, for example, a device for quantifying the physical quantity of a substance to be irradiated. For example, the optical physical quantity measuring device is a device that quantifies the physical quantities of nitrates, nitrites, ammonium salts, chloride salts, bromides, iodides, sulfates, sulfites, peroxomonosulfates, peroxodisulfates, thiosulfates in water, or nitrogen dioxide, nitric oxide, dinitrogen monoxide, ammonia, sulfur monoxide, sulfur dioxide, sulfur trioxide, disulfur monoxide, hydrogen sulfide, ozone, carbon monoxide dichloride, etc. in the air using ultraviolet light. Furthermore, the physical quantity of substances that absorb ultraviolet light with a wavelength of 200 nm or more and less than 240 nm (e.g., organic matter) may also be quantified. Specifically, in an optical physical quantity measuring device equipped with a light-emitting unit and a light-receiving unit, the light emitted from the light-emitting unit is received by the light-receiving unit through the water or gas to be measured. In underwater measurements, this can be used for water quality testing of tap water and sewage, seawater, aquaculture, groundwater, aquariums, and wastewater from textile and chemical factories. In air measurements, this can be used for atmospheric quality testing, exhaust gas quality testing, livestock farming, peatland, volcanoes, exhaust gas testing from textile and chemical factories, and hot spring areas.

[0016] The light-emitting unit according to this embodiment comprises a plurality of light-emitting diodes (hereinafter referred to as LEDs), which are semiconductor elements capable of emitting ultraviolet light. The light-emitting unit is not limited to LEDs, but may be a laser or the like. The light-emitting unit may have a configuration in which the LEDs are arranged in a straight line, a configuration in which the LEDs are arranged in concentric circles, or a configuration in which the LEDs are arranged on a curved surface. Furthermore, the LEDs may be configured so that each individual LED can be removed or replaced as a component from the optical physical quantity measuring device, or multiple LEDs may be mounted on a circuit board so that each individual LED cannot be removed or replaced as a component.

[0017] In the first embodiment, a case where the light emitting unit includes two light emitting diodes (LED1 (an example of the first light emitting diode) and LED2 (an example of the second light emitting diode)) as a plurality of light emitting diodes will be described. In the following description, when the two LEDs 1 and 2 are not distinguished, they may simply be referred to as LEDs.

[0018] The light emitting unit according to the present embodiment includes a plurality of light emitting diodes (LED1 and LED2) that emit light having a wavelength of 200 nm or more and less than 240 nm. In LED1, the light emission output at each wavelength of 200 nm or more and less than 240 nm of LED1 is larger than each of the light emission outputs at the same wavelength of LED2. This can also be rephrased as saying that in the range of 200 nm or more and less than 240 nm of wavelength, the emission spectrum of LED2 is included in the emission spectrum of LED1. When such LED1 and LED2 are combined and provided in an optical physical quantity measuring device, two or more physical quantities of a measurement object can be measured with high accuracy and precision.

[0019] Here, as an example, a case where the first LED and the second LED included in the light emitting unit in the present embodiment are combined with a first LED having a peak wavelength of 230 nm and an emission spectrum width of 220 nm or more and 250 nm or less, and a second LED having a peak wavelength of 226 nm and an emission spectrum width of 220 nm or more and 250 nm or less will be described. Fig. 1(a) shows the relationship between the emission wavelength and the emission intensity of the first LED and the second LED in the example. In this case, when quantifying the respective concentrations of ammonium sodium (NaNH ,

[0021] ) and sodium nitrate (NaNO ３ ) in water, from the amount of light detected by the light receiving unit, each physical quantity can be calculated by solving two equations expressed by the following arithmetic expressions of the first LED and the arithmetic expressions of the second LED.

[0020]

[0021] As a comparative example, for the LED1 and LED2 included in the light-emitting unit in the present embodiment, a case where a first LED having a peak wavelength of 230 nm and an emission spectrum width of 220 nm or more and 250 nm or less, and a second LED having a peak wavelength of 219 nm and an emission spectrum width of 210 nm or more and 240 nm or less are combined will be described. FIG. 1(b) shows the relationship between the emission wavelength and the emission intensity of the first LED and the second LED in the comparative example.

[0022] In this case, when quantifying the respective concentrations of ammonium sodium (NaNH ４ ), and sodium nitrate (NaNO ３ ), two equations expressed by the following arithmetic expressions of the first LED and the arithmetic expression of the second LED are to be solved from the amount of light detected by the light-receiving unit. At this time, since the second LED emits light at wavelengths (210 nm or more and less than 220 nm) where the first LED does not emit light, it is affected by interfering ions such as oxygen (O ２ ). Therefore, the arithmetic expressions are as follows, and since the calculation term of O ２ is added to the second LED, the accuracy and precision of measuring the respective concentrations of ammonium sodium (NaNH ４ ), and sodium nitrate (NaNO ３ ) as the quantitative concentrations decrease.

[0023]

[0024] In addition, ultraviolet light with a wavelength of 200 nm or more and less than 240 nm may be radiated outside the optical physical quantity measuring device. That is, there is a possibility that the human body is irradiated with ultraviolet light. In this case, it is preferable that the ultraviolet irradiation amounts of LED1 and LED2, and the ultraviolet irradiation amount per specified time when irradiated simultaneously, are smaller than the allowable exposure amounts defined by the ACGIH (American Conference of Governmental Industrial Hygienists) and the Japanese Society of Occupational Health. At this time, it is more preferable that the relationship between the emission spectra of LED1 and LED2 is the same as the relationship between LED1 and LED2 included in the light-emitting unit in the present embodiment described above.

[0025] Furthermore, ultraviolet light with a wavelength of 200 nm or more and less than 240 nm has the effect of keeping the outer wall of the optical physical quantity measuring device clean through ultraviolet irradiation. At this time, there is a lower limit to the amount of ultraviolet irradiation necessary to reduce the growth of viruses and bacteria, and it is more preferable that the amount of ultraviolet irradiation per specified time when LED1 and LED2 irradiate ultraviolet light simultaneously exceeds this lower limit. In addition, by suppressing the growth of viruses and bacteria, it is possible to prevent a decrease in measurement accuracy due to contamination.

[0026] Based on the light output of LED1, the maximum possible value of the integrated light output (maximum luminescence potential) of the optical physical quantity measuring device in the wavelength range of 200 nm to less than 240 nm can be more easily estimated. Here, "maximum luminescence potential" is the hypothetical light output that the optical physical quantity measuring device is expected to emit if all LEDs mounted on the device are LEDs with performance equivalent to LED1. In reality, the light output of LEDs other than LED1 mounted on the optical physical quantity measuring device is lower than that of LED1, so the light output of the optical physical quantity measuring device will be lower than the maximum luminescence potential.

[0027] Furthermore, by combining LED1 and LED2 in this way and installing them in an optical physical quantity measuring device, it becomes easier to estimate the minimum value (minimum possible luminescence) that the integrated luminescence output of the optical physical quantity measuring device can take in the wavelength region of 200 nm to less than 240 nm, based on the luminescence output of LED2. Here, the "minimum possible luminescence" is a hypothetical luminescence output that the optical physical quantity measuring device is expected to emit if all LEDs mounted on the optical physical quantity measuring device are LEDs with performance equivalent to LED2. In reality, the luminescence output of LEDs other than LED2 mounted on the optical physical quantity measuring device is higher than that of LED2, so the luminescence output of the optical physical quantity measuring device will be higher than the minimum possible luminescence.

[0028] Figure 2 shows the emission spectra of LED1 and LED2, which represent an example of a specific combination in the optical physical quantity measuring device according to this embodiment. Note that in Figure 2, the emission output of each LED below 10 μW is excluded from the discussion because the difference from the measurement noise is not clear. As shown in Figure 2, in the region of wavelengths from 200 nm to less than 240 nm, the emission output of LED1, shown by the dashed line, is greater than the emission output of LED2, shown by the solid line, at all wavelengths. In this case, the emission output obtained by integrating the emission outputs of each wavelength in the region of wavelengths from 200 nm to less than 240 nm for the optical physical quantity measuring device equipped with LED1 and LED2 is lower than when two LEDs with performance equivalent to LED1 are installed, and higher than when two LEDs with performance equivalent to LED2 are installed. As a result, when setting an upper limit standard for the emission output of the optical physical quantity measuring device, by selecting LED1 such that the maximum possible emission value does not exceed the upper limit standard, it is possible to manufacture an optical physical quantity measuring device equipped with LED1 and LED2 in which the emission output of the optical physical quantity measuring device does not exceed the upper limit standard.

[0029] Here, the "permissible upper limit" is the upper limit of the emission output that an optical physical quantity measuring device may emit, which is set considering the impact on the ultraviolet irradiation target (safety, etc.) when the optical physical quantity measuring device is actually used. Similarly, when setting a standard for the permissible lower limit of the emission output of an optical physical quantity measuring device, if we assume an optical physical quantity measuring device equipped with two LEDs with performance equivalent to LED2, by selecting LED2 such that the minimum possible emission value of the optical physical quantity measuring device does not fall below the permissible lower limit, it is possible to manufacture an optical physical quantity measuring device equipped with LED1 and LED2 in which the emission output of the optical physical quantity measuring device does not fall below the lower limit standard.

[0030] Here, the "permissible lower limit" is the lower limit of the emission output that the optical physical quantity measuring device must emit, which is set considering, for example, the effect on the ultraviolet irradiation target during the actual use of the optical physical quantity measuring device (such as guaranteeing the effect of inactivating viruses or bacteria on the outer wall or window of the optical physical quantity measuring device). In an optical physical quantity measuring device using LED1 and LED2, the effort of checking whether the emission output in the wavelength range of 200 nm to less than 240 nm after the optical physical quantity measuring device has been manufactured exceeds the permissible upper limit or falls below the permissible lower limit can be eliminated.

[0031] Ultraviolet light emitted from LEDs becomes more harmful to human skin and eyes when the emission wavelength exceeds 240 nm, as the permissible upper limit of irradiation decreases. Therefore, it is undesirable for the emission output of one of the two LEDs used in the optical physical quantity measuring device to be greater depending on the wavelength in the region above 240 nm. In other words, it is preferable that the emission output of LED 1 is greater than that of LED 2 at all wavelengths in the region between 240 nm and 280 nm. This is because, when setting a standard for the permissible upper limit of emission output in the region between 240 nm and 280 nm of the optical physical quantity measuring device, it is possible to compare the emission output at each wavelength assumed based on the emission spectral shape of LED 1 with the actual emission output of the optical physical quantity measuring device. In other words, when an optical physical quantity measuring device is manufactured using LED 1 and LED 2 as described in this embodiment, the effort of checking whether the emission output at wavelengths between 240 nm and 280 nm exceeds the permissible upper limit after the optical physical quantity measuring device is manufactured can be eliminated. Furthermore, when an optical physical quantity measuring device is manufactured using LED1 and LED2 as described in this embodiment, the number of measurement points when measuring the emission spectrum can be reduced, which leads to a reduction in inspection time.

[0032] In this embodiment, the emission peak wavelength of LED1 may be greater than the emission peak wavelength of LED2. For example, in Figure 2, the emission peak wavelength of LED1 is 230 nm, and the emission peak wavelength of LED2 is 229 nm. By combining LED1 and LED2 such that the emission peak wavelength of LED1 is greater than the emission peak wavelength of LED2, it becomes easier to suppress the emission output of LED2 in the wavelength range of 240 nm to 280 nm from being higher than the emission output of LED1 in the same wavelength range for a portion of the wavelength. This is because the shape of the emission spectrum, which is normally defined by the emission output with respect to the wavelength of an LED, shifts without a large change in its external shape when the emission peak wavelength is changed. Therefore, by making the emission peak wavelength of LED1, which has a large emission output, greater than the emission peak wavelength of LED2, it becomes easier for the emission output of LED1 in the wavelength range of 240 nm to 280 nm to be higher than the emission output of LED2 at the same wavelength.

[0033] Furthermore, for ultraviolet light with wavelengths between 200 nm and 240 nm, the absorption coefficient increases with decreasing wavelength for many materials. Therefore, by making the emission peak wavelength of LED1, which has high emission intensity, greater than the emission peak wavelength of LED2, which has low emission intensity, the difference in influence due to interfering ions can be reduced.

[0034] In this embodiment, the peak emission wavelength of LED1 is 200 nm or more and less than 240 nm. By setting the peak emission wavelength of LED1 to less than 240 nm, it becomes easier to select a preferred combination of LEDs as LED1 and LED2. More specifically, it becomes easier to select LED1 and LED2 that emit light in the wavelength range of 200 nm or more and less than 240 nm, where the emission output of LED1 in both the wavelength range of 200 nm or more and less than 240 nm and the wavelength range of 240 nm or more and 280 nm is greater than the emission output of LED2 at the same wavelength, and the peak emission wavelength of LED1 is greater than the peak emission wavelength of LED2. Furthermore, by setting the peak emission wavelength of LED1 to less than 240 nm, it is possible to reduce the influence of interfering ions that absorb a lot of light in the wavelength range of 240 nm or more, such as organic substances that have conjugated bonds in their molecular structure.

[0035] As mentioned above, it is preferable that the peak wavelength of LED2 is shorter than the peak wavelength of LED1. When the peak wavelength of ultraviolet light emitted from an LED is 200 nm or more and less than 240 nm, the luminous efficiency of the LED generally decreases as the peak wavelength of ultraviolet light decreases. For this reason, when the peak wavelength of LED1 is 200 nm or more and less than 240 nm, it is easier to select LED2 in this embodiment if the peak wavelength of LED2 is also 200 nm or more and less than 240 nm. When the peak wavelengths of LED1 and LED2 are 240 nm or more and 280 nm or less, it becomes difficult to determine whether the light emission output conditions for the combination of LED1 and LED2 described in this embodiment are met based on the peak wavelength alone. For this reason, it becomes necessary to compare the light emission output at each wavelength of LED1 and LED2, making it difficult to select the combination of LED1 and LED2.

[0036] On the other hand, when the peak wavelength of ultraviolet light emitted from the LED is between 240 nm and 280 nm, the luminous efficiency of the LED does not necessarily improve as the peak wavelength of ultraviolet light decreases, and selecting the combination of LED1 and LED2 described in this embodiment requires considerable effort. Therefore, it is preferable that the peak emission wavelength of LED1 is between 200 nm and 240 nm.

[0037] In this embodiment, LED 1 emits only light with a wavelength of 220 nm or longer. This means that LED 1 does not emit light in the wavelength range below 220 nm. Ultraviolet light emitted by optical physical quantity measuring devices is absorbed by oxygen in the atmosphere at wavelengths of 240 nm or less, generating ozone, a harmful substance. The amount of ozone exposure is defined by organizations such as ACGIH (American Conference of Governmental Industrial Hygienists) and the Japan Society for Occupational Health, and it is required that the concentration in the usage space not exceed the permissible limit. Furthermore, by preventing the absorption of oxygen itself, it is possible to prevent oxygen from becoming an interfering ion during measurement, which would reduce the accuracy and precision of the measurement.

[0038] The amount of oxygen absorbed by ultraviolet light and the amount of ozone produced increase as the wavelength of ultraviolet light decreases. For this reason, when the wavelength of ultraviolet light is less than 220 nm, the interference effect by oxygen is large and the amount of ozone produced is large; when the wavelength of ultraviolet light is less than 210 nm, the interference effect by oxygen is even greater and the amount of ozone produced is large; and when the wavelength of ultraviolet light is less than 200 nm, the interference effect by oxygen is even greater and the amount of ozone produced is large. For this reason, it is not advisable to emit light with a wavelength of less than 220 nm from an optical physical quantity measuring device.

[0039] Here, if LED1 is an LED that emits only light with a wavelength of 220 nm or longer, the light emission output of LED2 in the wavelength range of 200 nm to less than 240 nm will be lower than the light emission output of LED1. Therefore, LED2 will also inevitably be an LED that emits only light with a wavelength of 220 nm or longer. In this case, LED2 will have a peak emission wavelength of 220 nm or longer, just like LED1. In other words, if LED1 is an LED that emits only light with a wavelength of 220 nm or longer, LED2 will also be an LED that emits only light with a wavelength of 220 nm or longer, and the optical physical quantity measuring device equipped with LED1 and LED2 will also emit only light with a wavelength of 220 nm or longer. Therefore, the interference effect of oxygen when using the optical physical quantity measuring device is small and the amount of ozone generated is reduced.

[0040] The probability of failure due to ultraviolet light in the wavelength range of 230 nm to less than 240 nm emitted from an optical physical quantity measuring device exceeding the permissible upper limit is higher than the probability of failure due to ultraviolet light in the wavelength range of 220 nm to less than 230 nm emitted from an optical physical quantity measuring device exceeding the permissible upper limit. This is because, according to the permissible exposure limits stipulated by ACGIH (American Conference of Governmental Industrial Hygienists) and the Japan Society for Occupational Health, the permissible exposure limit for the wavelength range of 220 nm to less than 230 nm is lower than the permissible exposure limit for the wavelength range of 230 nm to less than 240 nm. In order to prevent malfunctions in the optical physical quantity measuring device, it is preferable that the relative value calculated by dividing the light emission output obtained by integrating the light emission output of LED1 at each wavelength in the wavelength range of 220 nm to less than 230 nm by the light emission output obtained by integrating the light emission output of LED2 (any light-emitting diode other than LED1 among the multiple light-emitting diodes) at each wavelength in the wavelength range of 220 nm to less than 230 nm is smaller than the relative value calculated by dividing the light emission output obtained by integrating the light emission output of LED1 at each wavelength in the wavelength range of 230 nm to less than 240 nm by the light emission output obtained by integrating the light emission output of LED2 at each wavelength in the wavelength range of 230 nm to less than 240 nm.

[0041] To suppress the occurrence of defective products, the light emission output of the optical physical quantity measuring device must be precisely controlled. The permissible upper limit is higher as the wavelength of ultraviolet light emitted by the optical physical quantity measuring device decreases, based on the permissible exposure levels stipulated by organizations such as ACGIH (American Conference of Governmental Industrial Hygienists) and the Japan Society for Occupational Health. In the optical physical quantity measuring device according to this embodiment, the light emission output of LED 1 can be estimated based on the maximum possible emission value. In this case, the larger the relative value of the light emission output of LED 1 to the light emission output of LED 2, the lower the actual light emission output of the manufactured optical physical quantity measuring device will be compared to the estimated maximum possible emission value, and the lower the probability of exceeding the permissible upper limit.

[0042] In this embodiment, an optical physical quantity measuring device equipped with two LEDs, LED1 and LED2, has been described, but the device is not necessarily limited to this configuration. For example, the optical physical quantity measuring device may be equipped with three or more LEDs, such as LED1, LED2, LED3, etc. In an optical physical quantity measuring device equipped with three or more LEDs, the emission output of LED1 in the wavelength range of 200 nm to less than 240 nm is greater than the emission output of all other LEDs (LED2, LED3, etc.) at the same wavelength. The emission output of ultraviolet light at wavelengths of 200 nm to less than 240 nm emitted from such an optical physical quantity measuring device is smaller than the emission output of ultraviolet light at wavelengths of 200 nm to less than 240 nm emitted from an optical physical quantity measuring device in which all LEDs have been replaced with LEDs of equivalent performance to LED1. Therefore, the probability that the emission output of the optical physical quantity measuring device will exceed the upper limit of the allowable emission output is reduced.

[0043] Furthermore, in an optical physical quantity measuring device equipped with three or more LEDs, the emission output of LED2 at each wavelength between 200 nm and 240 nm is smaller than the emission output of all other LEDs (LED1, LED3, ...) at the same wavelength. The emission output of ultraviolet light between 200 nm and 240 nm emitted from such an optical physical quantity measuring device will be higher than the emission output of ultraviolet light between 200 nm and 240 nm emitted from an optical physical quantity measuring device in which all LEDs have been replaced with LEDs of equivalent performance to LED2. Therefore, the probability that the emission output of the optical physical quantity measuring device will fall below the lower limit of the allowable emission output is reduced.

[0044] (2) Inspection Method for Optical Physical Quantity Measuring Devices The inspection method for optical physical quantity measuring devices according to this embodiment will be explained using Figures 3 and 4. Figure 3 is a flowchart showing a method for inspecting optical physical quantity measuring devices by estimating the maximum possible emission value of the optical physical quantity measuring device. Figure 4 is a flowchart showing a method for inspecting optical physical quantity measuring devices by estimating the minimum possible emission value of the optical physical quantity measuring device.

[0045] (2-1) Estimation of maximum potential emission and determination of good / defective products The light emission output of LED1 is greater than that of LED2 in all wavelengths in the range of 200 nm to less than 240 nm. Therefore, if, for example, an allowable upper limit (details will be described later), which is the maximum value of the light emission output of an optical physical quantity measuring device that is permitted to emit light to the outside, is set, it is possible to determine whether the optical physical quantity measuring device is good or defective by comparing the light emission output of LED1 with the allowable upper limit.

[0046] The following describes a method for inspecting an optical physical quantity measuring device based on the maximum possible emission value of an optical physical quantity measuring device, which comprises LED 1 and LED 2, the LED whose emission output at each wavelength between 200 nm and 240 nm is smaller than the emission output of LED 1 at the same wavelength, with reference to Figure 3A. As shown in Figure 3A, first, the emission output of LED 1 at each wavelength between 200 nm and 240 nm is obtained (step S11). In step S11, the emission output at each predetermined wavelength between 200 nm and 240 nm of LED 1 can be measured to obtain the emission output at each of the above wavelengths. At this time, the numerical values ​​of the measured emission output may be processed to obtain the emission output at each wavelength.

[0047] For example, as shown in Figure 3B, step S11, which obtains the light emission output of LED 1 at each wavelength between 200 nm and 240 nm, may include measuring the light emission output of LED 1 at predetermined wavelengths between 200 nm and 240 nm (step S111), creating primary data based on the measured light emission output of LED 1 (step S112), and estimating the light emission output at each wavelength in an optical physical quantity measuring device using only the primary data of LED 1 (step S113). That is, when processing the numerical values ​​of the measured light emission output, the light emission output at each wavelength in the optical physical quantity measuring device estimated in step S113 is considered to be the light emission output of LED 1 at each wavelength between 200 nm and 240 nm. Here, "creating primary data" means, for example, processing the numerical values ​​of the measured light emission output into primary data such as a table or graph.

[0048] Furthermore, at this time, a predicted emission output may be obtained by using the emission output of LED1 at each wavelength that was actually measured, to predict the emission output of LED1 at wavelengths that were not actually measured, and the emission output may be supplemented with the predicted emission output. Specifically, for example, the emission output at 200 nm and the emission output at 202 nm may be measured, and the emission output at 201 nm may be obtained by approximating the midpoint between the emission output at 200 nm and the emission output at 202 nm. In other words, the emission output of LED1 at each wavelength that was actually measured and the predicted emission output of LED1 at wavelengths that were not actually measured may be considered as the emission output of LED1 at each wavelength between 200 nm and 240 nm.

[0049] Next, when LED1 is mounted on the optical physical quantity measuring device, the maximum possible emission value is estimated based on the emission output of LED1, which is the maximum value that the integrated emission output of the optical physical quantity measuring device can take for wavelengths between 200 nm and 240 nm (step S12). The "emission output" used here may be the measured emission output of LED1, as described above, or it may be primary data based on the measured emission output of LED1, or it may include the predicted emission output of LED1 at wavelengths that have not actually been measured. This calculation is performed, for example, to predict the total emission output of the optical physical quantity measuring device from only the emission output of LED1. In this case, "calculation" means multiplying the values ​​of the emission output of LED1 for each wavelength obtained in step S11 by a predetermined coefficient. The coefficient in this case may be a different value for each wavelength, or it may be a different value depending on the placement position of LED1 mounted on the optical physical quantity measuring device.

[0050] Another example of this calculation is a calculation performed to predict, for example, the amount of ultraviolet light with a wavelength of 200 nm or more and less than 240 nm emitted from an optical physical quantity measuring device that reaches a predetermined position from the light emission output of LED 1. In this case, "calculation" means multiplying the light emission output of LED 1 for each wavelength by a predetermined set of coefficients. In this case, the coefficients may differ depending on, for example, the position where LED 1 is placed, or depending on the structure of the device on which the optical physical quantity measuring device is mounted as a component, such as the light shielding or reflection structure.

[0051] The inspection method for optical physical quantity measuring devices according to this embodiment is particularly effective when applied to optical physical quantity measuring devices used as components of a device in which a reference value for the light emission output of the optical physical quantity measuring device that is permitted to be emitted to the outside is specified. Examples of such reference values ​​include the maximum value (permissible upper limit) of the light emission output of the optical physical quantity measuring device that is permitted to be emitted to the outside, and the minimum value (permissible lower limit) of the light emission output of the optical physical quantity measuring device that is permitted to be emitted to the outside. The permissible upper limit is the upper limit of the light emission output predetermined as a standard for good products, and the permissible lower limit is the lower limit of the light emission output predetermined as a standard for good products.

[0052] In such cases, during the manufacturing process of the optical physical quantity measuring device, the light output of the LED is compared with the aforementioned reference value under specified driving conditions to determine whether the optical physical quantity measuring device is a good product or a defective product. For example, when an optical physical quantity measuring device is used in a manner that may expose the human body to ultraviolet light, there is generally an upper limit of permissible time within which ultraviolet light exposure is permitted, determined considering the harmful effects on the human body.

[0053] In the manufacturing process of the optical physical quantity measuring device, in step S12, the maximum possible luminescence value calculated based solely on the light output of LED1 under specified driving conditions is compared with the permissible upper limit to determine whether the optical physical quantity measuring device is a good product or a defective product (steps S13 to S15). Specifically, in step S13, the maximum possible luminescence value calculated based solely on the light output of LED1 is compared with the permissible upper limit. If the maximum possible luminescence value is less than or equal to the permissible upper limit (Yes in step S13), the optical physical quantity measuring device is judged to be a good product (step S14). Also, in step S13, the maximum possible luminescence value calculated based solely on the light output of LED1 is compared with the permissible upper limit. If the maximum possible luminescence value exceeds this permissible upper limit (No in step S13), the optical physical quantity measuring device is judged to be a defective product (step S15).

[0054] (2-2) Estimation of the minimum possible emission value and determination of good / defective products The light emission output of LED2 is lower than that of LED1 in all wavelengths in the range of 200 nm to less than 240 nm. For this reason, if, for example, an acceptable lower limit is set, which is the minimum value of the light emission output of a standard optical physical quantity measuring device within a standard time period for inactivating viruses and bacteria on the outer wall or window of the optical physical quantity measuring device, it is possible to determine whether the optical physical quantity measuring device is good or defective by comparing the light emission output of LED2 with the acceptable lower limit.

[0055] The following describes a method for inspecting an optical physical quantity measuring device based on the minimum possible emission value of the optical physical quantity measuring device, with reference to Figure 4. As shown in Figure 4A, first, the emission output of LED2 at each wavelength between 200 nm and 240 nm is obtained (step S21). In step S21, the emission output of LED2 at predetermined wavelengths between 200 nm and 240 nm is measured, thereby obtaining the emission output of each wavelength as described above. At this time, the numerical values ​​of the measured emission output may be processed to obtain the emission output of each wavelength.

[0056] For example, as shown in Figure 4B, step S21, which obtains the emission output of LED2 at each wavelength between 200 nm and 240 nm, may include measuring the emission output of LED2 at predetermined wavelengths between 200 nm and 240 nm (step S211), creating primary data based on the measured emission output of LED2 (step S212), and estimating the emission output at each wavelength in an optical physical quantity measuring device using only the primary data of LED2 (step S213). That is, when processing the numerical values ​​of the measured emission output, the emission output at each wavelength in an optical physical quantity measuring device estimated using only the primary data of LED2 estimated in step S213 is considered to be the emission output of LED2 at each wavelength between 200 nm and 240 nm.

[0057] Furthermore, at this time, a predicted emission output may be obtained by using the emission output of LED2 at each wavelength that was actually measured, to predict the emission output of LED2 at wavelengths that were not actually measured, and the emission output may be supplemented with the predicted emission output. In other words, the emission output of LED2 at each wavelength that was actually measured and the predicted emission output of LED2 at wavelengths that were not actually measured may be considered as the emission output of LED2 at each wavelength between 200 nm and 240 nm.

[0058] Similarly, the minimum possible emission value is estimated by calculating the emission output for each wavelength when LED2 is mounted on the optical physical quantity measuring device using only the emission output of LED2 (step S22). As described above, the "emission output" may be the measured emission output of LED2, or it may be primary data based on the measured emission output of LED2, or it may include the predicted emission output of LED2 at wavelengths that have not been actually measured. In this case as well, similar to the case in which the maximum possible emission value is estimated, the minimum possible emission value can be estimated by performing a calculation in which a predetermined coefficient is multiplied by the emission output of LED2 for each wavelength.

[0059] In such cases, during the manufacturing process of the optical physical quantity measuring device, the light output of the LED is compared with the aforementioned reference value under specified driving conditions to determine whether the optical physical quantity measuring device is a good or defective product. For example, in order to perform measurements without being overwhelmed by noise in the measuring instrument, there is generally a reference light output value (permissible lower limit) within a reference time.

[0060] In the manufacturing process of the optical physical quantity measuring device, in step S22, under specified driving conditions, the minimum possible emission value calculated based solely on the light output of LED2 is compared with the allowable lower limit to determine whether the optical physical quantity measuring device is a good product or a defective product (steps S23 to S25). Specifically, in step S23, the minimum possible emission value calculated based solely on the light output of LED2 is compared with the allowable lower limit. If the minimum possible emission value is greater than or equal to the allowable lower limit (Yes in step S23), the optical physical quantity measuring device is judged to be a good product (step S24). Also, in step S23, the minimum possible emission value calculated based solely on the light output of LED2 is compared with the allowable lower limit. If the minimum possible emission value falls below this allowable lower limit (No in step S23), the optical physical quantity measuring device is judged to be a defective product (step S25).

[0061] In conventional optical physical quantity measuring devices, in the wavelength range of 200 nm to less than 240 nm, the light emission output of LED 1 may be greater than or less than that of LED 2 at the same wavelength at some wavelengths. Therefore, with conventional optical physical quantity measuring devices, it is necessary to inspect the optical physical quantity measuring device in a different way than the optical physical quantity measuring device according to the embodiment described above.

[0062] The following describes the inspection method of a conventional optical physical quantity measuring device using Figures 5A and 5B. Figure 5A is a flowchart showing a method for inspecting a conventional optical physical quantity measuring device by estimating the maximum possible emission value, and Figure 5B is a flowchart showing a method for inspecting a conventional optical physical quantity measuring device by estimating the minimum possible emission value. In a conventional optical physical quantity measuring device, first, the emission output of LED1 for each wavelength is obtained (step S31). Next, the emission output of LED2 for each wavelength is obtained (step S32). The "emission output" used here may be the measured emission output of LED1, as described above, or it may be primary data based on the measured emission output of LED1, or it may include the predicted emission output of LED1 at wavelengths that have not actually been measured. The same applies to LED2.

[0063] Next, the emission output for each wavelength of LED1 obtained in step S31 and the emission output for each wavelength of LED2 obtained in step S32 are compared for each wavelength, and the emission output with the larger output for each wavelength is extracted (step S33). Subsequently, the maximum emission potential is estimated by calculating the emission output for each wavelength when mounted on an optical physical quantity measuring device using the extracted emission output for each wavelength (the emission output with the larger output among the emission outputs of LED1 and LED2) (step S34). Alternatively, the emission output with the larger output for each wavelength among the emission outputs of LED1 and LED2 extracted in step S34 may be processed into secondary data such as a table or graph. In this case, the maximum emission potential is estimated by multiplying the secondary data by a coefficient.

[0064] Next, in step S34, the maximum luminescence potential estimated under specified driving conditions is compared with the allowable upper limit to determine whether the optical physical quantity measuring device is good or defective (steps S35 to S37). Specifically, in step S35, the maximum luminescence potential calculated based on the light output of LED1 and LED2 is compared with the allowable upper limit. If the maximum luminescence potential is less than or equal to the allowable upper limit (Yes in step S35), the optical physical quantity measuring device is judged to be good (step S36). Also, in step S35, the maximum luminescence potential calculated based on the light output of LED1 and LED2 is compared with the allowable upper limit. If the maximum luminescence potential exceeds the allowable upper limit (No in step S35), the optical physical quantity measuring device is judged to be defective (step S37).

[0065] Furthermore, as shown in Figure 5B, in a conventional optical physical quantity measuring device, first, the emission output of LED 1 for each wavelength is obtained (step S41). Next, the emission output of LED 2 for each wavelength is obtained (step S42). Then, the emission output of LED 1 obtained in step S31 and the emission output of LED 2 obtained in step S32 are compared for each wavelength, and the emission output with the smaller output for each wavelength is extracted (step S43). Next, the emission output for each wavelength when mounted on the optical physical quantity measuring device is calculated using the extracted emission outputs for each wavelength (the emission output with the smaller output among the emission outputs of LED 1 and LED 2) to estimate the minimum possible emission value (step S44).

[0066] Next, in step S44, the minimum possible luminescence value estimated under specified driving conditions is compared with the allowable lower limit to determine whether the optical physical quantity measuring device is good or defective (steps S45 to S47). Specifically, in step S45, the minimum possible luminescence value calculated based on the light output of LED1 and LED2 is compared with the allowable lower limit. If the minimum possible luminescence value is greater than or equal to the allowable lower limit (Yes in step S45), the optical physical quantity measuring device is judged to be good (step S46). Also, in step S45, the minimum possible luminescence value calculated based on the light output of LED1 and LED2 is compared with the allowable lower limit. If the minimum possible luminescence value is less than the allowable lower limit (No in step S45), the optical physical quantity measuring device is judged to be defective (step S47).

[0067] As described above, when inspecting a conventional optical physical quantity measuring device, it is necessary to compare the light emission output of LED1 and LED2 for each wavelength and extract the light emission output that is high or low for each wavelength. On the other hand, when inspecting the optical physical quantity measuring device according to this embodiment, it is not necessary to compare the light emission output of LED1 and LED2 for each wavelength and extract the light emission output that is high or low for each wavelength. In other words, in the inspection method of the optical physical quantity measuring device according to this embodiment, the step of comparing the measured light emission outputs of LED1 and LED2 with each other, or their primary data with each other, is unnecessary, so the data processing time can be shortened, and the maximum and minimum possible values ​​of light emission can be estimated more easily than in the conventional method.

[0068] To improve measurement accuracy and precision, reduce costs, and lower prices, it is necessary to minimize defective products. By using the optical physical quantity measuring device of this embodiment, the occurrence of defective products can be reduced. Specifically, when LED1 and LED2 of this embodiment are used in combination, it is possible to suppress the manufacture of optical physical quantity measuring devices that have a light emission output exceeding the permissible upper limit. Furthermore, when LED1 and LED2 of this embodiment are used, it is possible to suppress the manufacture of optical physical quantity measuring devices that have a light emission output below the permissible lower limit.

[0069] Furthermore, by using LED1 and LED2 of this embodiment in combination, it becomes possible to simplify the inspection of the optical physical quantity measuring device and reduce manufacturing costs. Conventionally, the characteristics of each LED had to be inspected before being mounted on the optical physical quantity measuring device, and then the luminescence characteristics of the optical physical quantity measuring device had to be inspected again. However, with the optical physical quantity measuring device of this embodiment, the maximum and minimum possible luminescence values ​​at each wavelength of LED1 and LED2 can be estimated with high accuracy, eliminating the need for further inspection of the luminescence characteristics.

[0070] If the combination of LED1 and LED2 described in this embodiment is not used, the light emission output of LED2 will be greater than that of LED1 in some wavelength ranges between 200 nm and 240 nm. In this case, it becomes difficult to confirm that the light emission output of the optical physical quantity measuring device does not exceed the standard in this wavelength range. This is because the light emission output of the optical physical quantity measuring device equipped with two LEDs is not necessarily less than or equal to the maximum possible emission value when assuming an optical physical quantity measuring device equipped with two LEDs of the same performance as LED1. Similarly, in this wavelength range, it becomes difficult to confirm that the light emission output of the optical physical quantity measuring device does not fall below the standard. This is because the light emission output of the optical physical quantity measuring device equipped with two LEDs is not necessarily greater than or equal to the minimum possible emission value when assuming an optical physical quantity measuring device equipped with two LEDs of the same performance as LED2. In other words, if the combination of LED1 and LED2 described in this embodiment is not used, it becomes difficult to estimate the emission spectrum of a single optical physical quantity measuring device from the emission spectrum of the LEDs.

[0071] Furthermore, the characteristics of the optical physical quantity measuring device are determined by the characteristics of the mounted LED 1 and LED 2. Therefore, if the combination of LED 1 and LED 2 described in this embodiment is not used, different calculation formulas would have to be used for each optical physical quantity measuring device depending on the characteristics of each mounted LED when estimating the light emission output of the optical physical quantity measuring device at wavelengths of 200 nm to less than 240 nm. On the other hand, as described above, in the optical physical quantity measuring device of this embodiment, the maximum possible light emission at each wavelength can be easily estimated from the characteristics of LED 1, and the minimum possible light emission value can be easily estimated from the characteristics of LED 2. Therefore, in the optical physical quantity measuring device according to this embodiment, there is no need to perform complex calculations for each wavelength based on the light emission output of LED 1 and LED 2, and inspection of the optical physical quantity measuring device can be omitted.

[0072] Furthermore, it is possible to determine whether an optical physical quantity measuring device is a good product simply by comparing the maximum luminescence potential of the optical physical quantity measuring device, calculated from the light emission output of LED1 at wavelengths between 200 nm and 240 nm, with the permissible upper limit. Specifically, if the maximum luminescence potential of LED1 does not exceed the permissible upper limit, the optical physical quantity measuring device is determined to be a good product, and if the maximum luminescence potential of LED1 exceeds the permissible upper limit, the optical physical quantity measuring device is determined to be a defective product. Similarly, for LED2, it is also possible to determine whether an optical physical quantity measuring device is a good product simply by comparing the minimum luminescence potential of the optical physical quantity measuring device, calculated from the light emission output of LED2 at wavelengths between 200 nm and 240 nm, with the permissible lower limit. Specifically, if the minimum luminescence potential of LED2 does not fall below the permissible lower limit, the optical physical quantity measuring device is determined to be a good product, and if the minimum luminescence potential of LED2 falls below the permissible lower limit, the optical physical quantity measuring device is determined to be a defective product.

[0073] Furthermore, when using an optical physical quantity measuring device, both LED1 and LED2 degrade over time, and their light output decreases. The light output of LEDs generally decreases along an arbitrary life curve. In the case of LEDs used for the same amount of time under the same temperature and humidity conditions, LEDs with higher initial light output will maintain higher light output after use. In other words, after use, LED1 will always have a higher light output than LED2. Therefore, the maximum possible light output of the optical physical quantity measuring device after use can be estimated by measuring the light output of LED1 at each wavelength after use. Similarly, the minimum possible light output of the optical physical quantity measuring device after use can be estimated by measuring the light output of LED2 at each wavelength after use.

[0074] These characteristics are particularly useful when it is difficult to measure the light emission output of an optical physical quantity measuring device, for example, when the optical physical quantity measuring device itself is incorporated as a component into a larger device, making it difficult to inspect the degradation of the optical physical quantity measuring device alone. Alternatively, an ultraviolet sensor for evaluating the light emission output may be installed near LED 1 to monitor the degradation of LED 1. Or, LED 1 may be positioned inside the optical physical quantity measuring device at a location where the light emission of the LED is easiest to evaluate, and the emission spectrum of LED 1 may be acquired using another inspection device that uses an ultraviolet sensor.

[0075] In order to omit the inspection process of the optical physical quantity measuring device according to this embodiment, the light emission measurement of LED1 and LED2 may be performed at the LED manufacturing site, and the measurement results may be provided to the manufacturing site of the optical physical quantity measuring device. This allows the manufacturing site of the optical physical quantity measuring device to omit the inspection process of the optical physical quantity measuring device after assembly.

[0076] Furthermore, when manufacturing the optical physical quantity measuring device of this embodiment, it is preferable to manufacture and store in advance groups of LED1 containing multiple LED1s and groups of LED2 whose emission output at each wavelength between 200 nm and 240 nm is always smaller than the emission output at the same wavelength of any LED (LED1) in the group of LED1. This allows for the random selection of LED1 from the group of LED1 and the random selection of LED2 from the group of LED2 to create combinations. Therefore, during inspection of the optical physical quantity measuring device, it is not necessary to perform complex calculations such as comparing the emission output at each wavelength according to the combination of LED1 and LED2, and the inspection of the optical physical quantity measuring device can be omitted. Moreover, by managing the inventory of LED1 within the group of LED1 and the inventory of LED2 within the group of LED2, it is possible to prioritize the production of the group of LED1 or LED2 that is in short supply, thereby improving the production efficiency of the optical physical quantity measuring device.

[0077] Furthermore, in order to reduce the selection and assembly costs at the manufacturing site of the optical physical quantity measuring device, sorting of LED1 or LED2 may be performed at the LED manufacturing site. By separating LED1 and LED2 into separate containers (e.g., bottles) at the LED manufacturing site and providing them to the manufacturing site of the optical physical quantity measuring device, it is possible to suppress the possibility of workers at the optical physical quantity measuring device manufacturing site mixing up LED1 and LED2, and to manage the inventory of LED1 and LED2 separately, thereby reducing the selection costs of LED1 and LED2 or the assembly costs of the optical physical quantity measuring device.

[0078] (3) Configuration of each part of the optical physical quantity measuring device The following describes in more detail the light-emitting unit and other functional units that constitute the optical physical quantity measuring device. <Optical physical quantity measuring device> The optical physical quantity measuring device according to this embodiment includes a plurality of light-emitting units that emit light with a wavelength of 200 nm or more and less than 240 nm. It may also have a plurality of light-receiving units corresponding to each of the plurality of light-emitting units, or a single light-receiving unit that receives separate light-receiving signals for the light emitted from the plurality of light-emitting units. It may also be provided with a filter for the purpose of limiting or attenuating the wavelength of the light emitted from the light-emitting units. Furthermore, it may be provided with an acquisition unit that acquires the amount of light received by the light-receiving unit from the light-emitting unit. Furthermore, it may be provided with a calculation unit that calculates at least two physical quantities of substances based on the amount of light received acquired by the acquisition unit. Furthermore, it may have a recording unit that records the calculation results such as the physical quantities calculated by the calculation unit and various data, or a storage unit that stores data. In addition, the optical physical quantity measuring device and external equipment may be connected by wire or wireless to construct an optical physical quantity measuring system. For example, data acquired by the acquisition unit and data calculated by the calculation unit may be stored on an external server. Furthermore, the data stored on the external server may be notified to the optical physical quantity measuring device. The calculation unit may be located externally, or it may read data stored in the memory unit from an external source and perform calculation processing, or it may perform calculation processing in an external calculation unit based on data stored on an external server.

[0079] The optical physical quantity measuring device according to this embodiment may be a device for quantifying the physical quantity of a substance to be irradiated. A physical quantity refers to the concentration, density, absorbance, size, purity, turbidity, and degree of mixing of a substance. The physical quantity of the irradiated substance may be that of one substance, or it may be that of two or more substances. The physical quantity of the irradiated substance may be that of a single substance, or it may be that of a mixture. The physical quantity of the irradiated substance may be measured solely from the signal corresponding to the emission from the light-emitting unit, or it may be calculated by multiplying the signal corresponding to the emission from the light-emitting unit by other information.

[0080] The optical physical quantity measuring device according to this embodiment may quantify the physical quantities of nitrates, nitrites, ammonium salts, chloride salts, bromides, iodides, sulfates, sulfites, peroxomonosulfates, peroxodisulfates, thiosulfates in water, or nitrogen dioxide, nitric oxide, dinitrogen monoxide, ammonia, sulfur monoxide, sulfur dioxide, sulfur trioxide, disulfur monoxide, hydrogen sulfide, ozone, and carbon monoxide in the air. In the case of salts dissolved in water, the cations include sodium ions, lithium ions, potassium ions, magnesium ions, calcium ions, boron ions, and aluminum ions, while the anions include fluoride ions, chloride ions, bromide ions, and iodide ions. The device may also quantify the physical quantities of substances that absorb ultraviolet light with wavelengths of 200 nm or more and less than 240 nm (e.g., organic matter). The optical physical quantity measuring device may receive light emitted from a light-emitting unit through the water or gas being measured using a light-receiving unit. Optical physical quantity measuring devices may be used for water quality testing of tap water and sewage, seawater, aquaculture, groundwater, aquariums, wastewater, and in air measurements, for atmospheric quality testing, exhaust gas quality testing, livestock farming, peatland, volcanoes, exhaust gas testing, and hot spring areas.

[0081] The optical physical quantity measurement device is such that the optical path of the light passing through the measurement target may be 250 nm or more and may be 100 m or less. By making the optical path of the light 250 nm or more and longer than the ultraviolet emission wavelength, the accuracy can be improved. By making the optical path length 100 m or less, the attenuation of the light in the measurement target can be reduced to improve the accuracy. The light emitting part and the light receiving part may or may not have the light receiving part in the direction in which the light distribution intensity of the light emitting part is maximum. The light receiving part may directly receive the light emitted from the light emitting part, or may conduct the light by providing a fiber or the like, and may be reflected by a dielectric multilayer film formed by laminating materials such as aluminum, rhodium, ruthenium, iridium, SiO ２ or HfO ２ and the like. The light emitting part and the light receiving part may have the light receiving part at a position where the light distribution intensities of a plurality of light emitting parts overlap in the direction where the light distribution intensity is large. Alternatively, there may be a plurality of light receiving parts in the direction where the light distribution intensity of the light emitting part is large.

[0082] The optical physical quantity measurement device may use a material with strong ultraviolet resistance at the portion where the light emitted from the light emitting part hits. Specifically, metals such as aluminum, iron, cobalt, and copper may be used. Alternatively, by using a material that absorbs ultraviolet rays such as carbon or silicon carbide, the reflection of light may be suppressed to improve the measurement accuracy. When using a material with lower ultraviolet resistance than metal, such as resin or plastic, the use location may be limited so that the ultraviolet light emission to be irradiated is minimized and used in combination with metal, or it may be a replaceable part.

[0083] In an optical physical quantity measuring device, the optical path (sample optical path) through which the light emitted from the light-emitting part passes when measuring the object to be measured may be exposed outside the optical physical quantity measuring device. This exposure eliminates the need for preparatory work such as opening the housing or lid, allowing measurements to begin immediately. Alternatively, the optical physical quantity measuring device may be separated from the outside by a housing or lid. Separation prevents contamination of the sample optical path by fingerprints or other marks, which can reduce measurement accuracy, and prevents damage to the sample optical path by bumping it against the floor or wall. If the optical physical quantity measuring device is separated from the outside, the sample may be introduced only during measurement by opening the housing or lid, or by using a pump. The housing or lid may also have a partial through-hole connecting to the outside of the optical physical quantity measuring device. The presence of a through-hole allows for the dissipation of heat generated by the electrical circuits within the optical physical quantity measuring device, preventing it from remaining inside the device; allows for the introduction of a sample into the sample optical path via the through-hole; and enables visual inspection of the inside of the optical physical quantity measuring device.

[0084] An optical physical quantity measuring device may be equipped with a temperature sensor. The temperature sensor may be a thermocouple thermometer, resistance thermometer, radiation thermometer, glass thermometer, filled thermometer, bimetallic thermometer, etc. By equipping the optical physical quantity measuring device with a temperature sensor, temperature correction can be performed in the optical measurement, enabling highly accurate measurements. Specifically, when the change in the characteristics of the mounted component with respect to temperature is known in advance, the measurement result can be corrected using the temperature measured by the temperature sensor. In this context, mounted components may include light-emitting units, light-receiving units, or components described later such as humidity sensors, illuminance sensors, radiation sensors, clocks, airflow sensors, vibration sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD (chemical oxygen demand), BOD (biochemical oxygen demand), TOD (total oxygen consumption) measurement components, position sensors, weather measurement components, still image / video capture components, user authentication components, scanning components, direction measurement components, carbon dioxide concentration measurement components, oxygen concentration measurement components, sound generation components, sound recording components, components for storing information other than the physical quantity being measured, communication components, lighting, components for measuring the intensity of ultraviolet light in the external environment, biometric measurement components, atmospheric pressure measurement components, window cleaning components, pumps, etc. Furthermore, temperature correction may also be applied to the relationships between mounted components. For example, in the relationship between a light-emitting unit and a humidity sensor, if the relationship between the amount of light emitted and humidity is known in advance, further temperature correction may be applied. Alternatively, temperature correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and the relationship between the second light-emitting unit and the light-receiving unit. Applying such corrections enables more accurate measurements. Alternatively, it eliminates the need to consider the effect of temperature when checking measurement results and avoids the need to perform correction calculations later. Furthermore, it prevents incorrect corrections from being made when measuring ambient temperature using a temperature sensor other than the optical physical quantity measuring device, without realizing the discrepancy between the measured temperature and the actual temperature measured by the optical physical quantity measuring device. When the temperature exceeds or falls below a specified value, the measurement error increases, so the optical physical quantity measuring device may be prevented from taking measurements, or the measured data may be removed as anomalous data. Alternatively, temperatures other than those measured by the optical physical quantity measuring device may be detected. In short, using the optical physical quantity measuring device as a portable temperature measuring device reduces the number of items that need to be carried during fieldwork.

[0085] An optical physical quantity measuring device may be equipped with a humidity sensor. The humidity sensor may be driven by an electrical, wet-bulb, hair, electrolyte, ceramic, or thermoelectric method. By equipping an optical physical quantity measuring device with a humidity sensor, humidity correction can be performed in the optical physical quantity measurement, enabling highly accurate measurements. Specifically, when the change in the characteristics of mounted components in relation to humidity is known in advance, the measurement results can be corrected using the humidity measured by the humidity sensor. In this context, mounted components may include light-emitting units, light-receiving units, or, as described later, temperature sensors, illuminance sensors, radiation sensors, clocks, airflow sensors, vibration sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD, BOD, TOD measurement components, position sensors, weather measurement components, still image / video capture components, user authentication components, scanning components, direction measurement components, carbon dioxide concentration measurement components, oxygen concentration measurement components, sound generation components, sound recording components, components for storing information other than the physical quantity being measured, communication components, lighting, components for measuring the intensity of ultraviolet light in the external environment, biometric measurement components, atmospheric pressure measurement components, window cleaning components, pumps, etc. Furthermore, humidity correction may also be applied to the relationships between mounted components. For example, when the relationship between the light-emitting unit and the temperature sensor is known in advance, humidity correction may be applied to the relationship between the light-emitting unit and the temperature sensor. Alternatively, humidity correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and the relationship between the second light-emitting unit and the light-receiving unit. By applying such corrections, more accurate measurements become possible. Alternatively, it is possible to avoid the need to perform correction calculations later by considering the effect of humidity when checking measurement results. Alternatively, it is possible to avoid making incorrect corrections by measuring ambient humidity using a humidity sensor other than the optical physical quantity measuring device, without realizing that the result differs from the actual humidity measured by the optical physical quantity measuring device. When the humidity exceeds a specified value, the measurement error becomes large, so the optical measuring device may be prevented from taking measurements, or the measured data may be removed as abnormal data. Alternatively, the humidity of electrical equipment other than the optical measuring device may be detected. In short, by using the optical measuring device as a portable humidity measuring device, the number of items to carry during fieldwork can be reduced.

[0086] An optical measuring device may be equipped with an illuminance sensor. The illuminance sensor may be a phototransistor or a photodiode. By equipping an optical measuring device with an illuminance sensor, illuminance correction can be performed in optical measurements, enabling highly accurate measurements. Specifically, when the change in the characteristics of mounted components in relation to illuminance is known in advance, the measurement results can be corrected using the illuminance measured by the illuminance sensor. In this case, mounted components may refer to light-emitting parts, light-receiving parts, or, as described later, temperature sensors, humidity sensors, radiation sensors, clocks, airflow sensors, vibration sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD, BOD, TOD measuring components, position sensors, weather measuring components, still image / video capturing components, user authentication components, scanning components, direction measuring components, carbon dioxide concentration measuring components, oxygen concentration measuring components, sound generation components, sound recording components, components that store information other than the physical quantity being measured, communication components, lighting, external environment ultraviolet intensity measuring components, biometric measurement components, atmospheric pressure measuring components, window cleaning components, pumps, etc. Furthermore, illuminance correction may also be applied to the relationships between mounted components. For example, if the relationship between the light-emitting unit and the temperature sensor is known in advance, illuminance correction may be applied to that relationship. Alternatively, illuminance correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and to the relationship between the second light-emitting unit and the light-receiving unit. Applying such corrections enables more accurate measurements. Alternatively, it eliminates the need to consider the effect of illuminance when checking measurement results and to perform correction calculations later. Alternatively, it prevents the erroneous correction that occurs when measuring ambient illuminance using an illuminance sensor other than an optical measuring device, without realizing that it differs from the actual illuminance measured by the optical measuring device. When the illuminance measurement value exceeds the standard, the measurement error becomes large, so the optical physical quantity measuring device may be prevented from taking measurements, and the measured data may be removed as abnormal data. Alternatively, by using the optical physical quantity measuring device as a portable illuminance measuring device, the number of items to carry during fieldwork can be reduced.

[0087] Optical measuring devices may be equipped with radiation sensors. These radiation sensors may include dosimeters, Geiger-Müller tube radiation detectors, ionization chamber radiation detectors, and scintillation radiation detectors. By incorporating radiation sensors into optical measuring devices, radiation correction can be performed during optical measurements, enabling highly accurate measurements. Specifically, when the changes in the characteristics of mounted components in response to radiation are known in advance, the measurement results can be corrected using radiation measured by the radiation sensor. In this context, mounted components may include light-emitting units, light-receiving units, or, as described later, temperature sensors, humidity sensors, illuminance sensors, clocks, airflow sensors, vibration sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD, BOD, TOD measurement components, position sensors, weather measurement components, still image / video capture components, user authentication components, scanning components, direction measurement components, carbon dioxide concentration measurement components, oxygen concentration measurement components, sound generation components, sound recording components, components for storing information other than the physical quantity being measured, communication components, lighting, components for measuring the intensity of ultraviolet light in the external environment, biometric measurement components, atmospheric pressure measurement components, window cleaning components, pumps, etc. Furthermore, radiation correction may also be applied to the relationships between mounted components. For example, when the relationship between the light-emitting unit and the temperature sensor is known in advance, radiation correction may be applied to the relationship between the light-emitting unit and the temperature sensor. Alternatively, radiation correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and the relationship between the second light-emitting unit and the light-receiving unit. By applying such corrections, more accurate measurements become possible. Alternatively, it is possible to avoid the need to perform correction calculations later by considering the effects of radiation when checking measurement results. Alternatively, it is possible to avoid making incorrect corrections by measuring radiation in the environment that does not come into contact with the optical physical quantity measuring device using a radiation sensor other than the optical physical quantity measuring device, without realizing that the measured radiation differs from the actual radiation dose of the optical physical quantity measuring device. Alternatively, it is possible to estimate the timing of component replacement based on the cumulative radiation dose. When radiation is detected, the measurement error becomes large, so the optical physical quantity measuring device may be prevented from taking measurements, or the measured data may be removed as abnormal data. Alternatively, radiation from electrical equipment other than the optical physical quantity measuring device may be detected.In other words, by using an optical physical quantity measuring device as a portable radiation measuring device, the number of items to carry during fieldwork and other similar activities can be reduced.

[0088] Optical physical quantity measuring devices may be equipped with a clock. The clock may be an analog quartz clock, satellite radio-controlled clock, cuckoo clock, carousel watch, mechanical clock, chronograph, recommended clock, solar-powered clock, electric clock, or electronic clock. Equipping the device with a clock allows for recording the time of measurement, organizing fluctuations in measurement results in graphs or tables, and searching logs. The clock may or may not display numerical values ​​visible on the optical physical quantity measuring device. Using the optical physical quantity measuring device as a portable clock reduces the number of items carried during fieldwork.

[0089] An optical physical quantity measuring device may be equipped with an airflow sensor. The airflow sensor may be of the rotary, pressure, ultrasonic, thermal, or thermal-wire type. By equipping the optical physical quantity measuring device with an airflow sensor, airflow correction can be performed in the optical measurement, enabling highly accurate measurements. Specifically, when the change in the characteristics of the mounted component in relation to airflow is known in advance, the measurement results can be corrected using the airflow measured by the airflow sensor. In this context, mounted components may include light-emitting units, light-receiving units, or, as described later, temperature sensors, humidity sensors, illuminance sensors, clocks, radiation sensors, vibration sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD, BOD, TOD measurement components, position sensors, weather measurement components, still image / video capture components, user authentication components, scanning components, direction measurement components, carbon dioxide concentration measurement components, oxygen concentration measurement components, sound generation components, sound recording components, components that store information other than the physical quantity being measured, communication components, lighting, components that measure the intensity of ultraviolet light in the external environment, biometric measurement components, atmospheric pressure measurement components, window cleaning components, pumps, etc. Furthermore, airflow correction may also be applied to the relationships between mounted components. For example, in the relationship between a light-emitting unit and a temperature sensor, if the relationship between the amount of light emitted and the temperature is known in advance, airflow correction may be applied. Alternatively, airflow correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and the relationship between the second light-emitting unit and the light-receiving unit. By applying such corrections, more accurate measurements become possible. Alternatively, it is possible to avoid the need to perform correction calculations later by considering the effect of airflow when checking measurement results. Alternatively, it is possible to avoid making incorrect corrections by measuring the airflow in the environment that does not come into contact with the optical physical quantity measuring device using an airflow sensor other than the optical physical quantity measuring device, without realizing that the measured airflow differs from the actual airflow measured by the optical physical quantity measuring device. Alternatively, by measuring airflow simultaneously, more information about the environment at the measurement point can be obtained. When the airflow exceeds a specified value, the measurement error will be large, so the optical physical quantity measuring device may be prevented from taking measurements, or the measured data may be removed as abnormal data. Alternatively, airflow other than that measured by the optical physical quantity measuring device may be detected. In short, by using the optical physical quantity measuring device as a portable airflow measuring device, the number of items to carry during fieldwork can be reduced.

[0090] An optical physical quantity measuring device may be equipped with a vibration sensor. The vibration sensor may be of frequency-changing, piezoelectric, electrodynamic, servo, eddy current, capacitive, or optical type. By equipping the optical measuring device with a vibration sensor, vibration correction can be performed during optical measurement, enabling highly accurate measurements. Specifically, when the changes in the characteristics of mounted components in response to vibration are known in advance, the measurement results can be corrected using vibrations measured by the vibration sensor. In this context, mounted components may include light-emitting units, light-receiving units, or, as described later, temperature sensors, humidity sensors, illuminance sensors, clocks, radiation sensors, airflow sensors, leakage sensors, motion sensors, shock sensors, microwave sensors, COD, BOD, TOD measurement components, position sensors, weather measurement components, still image / video capture components, user authentication components, scanning components, direction measurement components, carbon dioxide concentration measurement components, oxygen concentration measurement components, sound generation components, sound recording components, components for storing information other than the physical quantity being measured, communication components, lighting, components for measuring the intensity of ultraviolet light in the external environment, biometric measurement components, atmospheric pressure measurement components, window cleaning components, pumps, etc. Furthermore, vibration correction may also be applied to the relationships between mounted components. For example, in the relationship between a light-emitting unit and a temperature sensor, if the relationship between the amount of light emitted and the temperature is known in advance, vibration correction may be applied further. Alternatively, vibration correction may be applied to the relationship between the first light-emitting unit and the light-receiving unit, and the relationship between the second light-emitting unit and the light-receiving unit. By applying such corrections, more accurate measurements become possible. Alternatively, it is possible to avoid the need to perform correction calculations later by considering the effects of vibration when checking measurement results. Alternatively, it is possible to avoid making incorrect corrections by using vibration sensors other than the optical physical quantity measuring device to measure vibrations in the environment that do not come into contact with the optical device, without realizing that the measured vibration differs from the actual vibration amount of the optical physical quantity measuring device. Alternatively, by measuring vibration simultaneously, it is possible to obtain more information about the environment at the measurement point. Alternatively, since the measurement error will be large when vibration is detected, the optical measuring device may be prevented from taking measurements, and the measured data may be removed as abnormal data. Alternatively, vibrations of electrical equipment other than the optical physical quantity measuring device may be detected. In short, by using the optical physical quantity measuring device as a portable vibration detection device, the number of items to carry during fieldwork and other activities can be reduced.

[0091] An optical physical quantity measuring device may be equipped with a leakage current sensor. The leakage current sensor may detect leakage current and also detect leakage current in the optical physical quantity measuring device. When leakage current is detected, the measurement error will increase, so the optical physical quantity measuring device may be prevented from taking measurements, or the measured data may be removed as abnormal data. Alternatively, leakage current may be detected in electrical equipment other than the optical physical quantity measuring device. In other words, by using an optical physical quantity measuring device as a portable leakage current detection device, the number of items to carry during fieldwork can be reduced.

[0092] Optical physical quantity measuring devices may be equipped with motion sensors. These motion sensors may include infrared sensors, ultrasonic sensors, microwave sensors, image recognition sensors with cameras, millimeter-wave sensors, etc. Equipping an optical physical quantity measuring device with a motion sensor allows it to be activated without pressing buttons, eliminating the need for preparation work during measurement. Alternatively, it can limit ultraviolet radiation, preventing exposure to ultraviolet light. Furthermore, the motion sensor can detect when suspicious individuals or animals approach the optical physical quantity measuring device, thus contributing to security in public facilities and buildings. This is particularly effective when the optical physical quantity measuring device is stationary and the user is not nearby.

[0093] An optical physical quantity measuring device may be equipped with a shock sensor. The shock sensor may be a piezoelectric sensor, a MEMS sensor, a train gauge sensor, etc. When a shock is detected, the measurement error will increase, so the optical physical quantity measuring device may be designed not to perform measurements, or the measured data may be removed as abnormal data. Alternatively, when a shock is detected, the optical physical quantity measuring device may be damaged, potentially causing ultraviolet light to leak to the user and exposing them to radiation, so the device may be designed so that the power is not turned on until the prescribed operation is completed.

[0094] Optical physical quantity measuring devices may be equipped with microwave sensors. By incorporating microwave sensors, it is possible to detect when suspicious individuals or animals approach the optical physical quantity measuring device. Therefore, this is useful for security in public facilities and buildings. This is particularly effective when the optical physical quantity measuring device is stationary and the user is not nearby. Optical physical quantity measuring devices may also be equipped with COD, BOD, and TOD sensors. By using the values ​​detected by the COD, BOD, and TOD sensors for correction, the measurement accuracy of the optical physical quantity measuring device can be improved.

[0095] Optical physical quantity measuring devices may be equipped with position sensors. By equipping an optical physical quantity measuring device with a position sensor, location information shown on a map or coordinate system can be saved along with the measurement results. This is particularly useful when conducting measurements while moving, such as during fieldwork. Optical physical quantity measuring devices may also be equipped with weather measurement components. By equipping a weather measurement component, information can be linked without needing to separately refer to the weather for that day. Furthermore, local weather conditions can be recorded. This is particularly useful when the optical physical quantity measuring device is stationary and the user is not nearby.

[0096] Optical physical quantity measuring devices may be equipped with still image and video capture components. This can reduce the number of items carried during fieldwork, for example. Alternatively, it allows for precise determination of the measurement location when remotely controlling the device with a robot such as a drone. Optical physical quantity measuring devices may also be equipped with user authentication components. This is particularly effective when limiting the use or maintenance of the optical physical quantity measuring device to specific individuals. Furthermore, it becomes possible to store the number of uses, duration, and device load for each user, enabling corresponding billing and usage allocation.

[0097] Optical physical quantity measuring devices may be equipped with scanning components. User information and location information may be read by reading barcodes, 2D codes, 3D codes, etc. Optical physical quantity measuring devices may also be equipped with direction-measuring components. Using an optical physical quantity measuring device as a portable direction-measuring device can reduce the number of items carried during fieldwork.

[0098] Optical physical quantity measuring devices may be equipped with a carbon dioxide concentration measuring component. Non-dispersive infrared absorption methods, semiconductor methods, thermal methods, etc., may be used to measure carbon dioxide concentration. By adding carbon dioxide measurement to the optical physical quantity measuring device, the error in the emission absorption in the ultraviolet region can be reduced by correcting for carbon dioxide concentration. Alternatively, if carbon dioxide needs to be measured separately from the object being measured by the optical physical quantity measuring device, only the optical physical quantity measuring device needs to be carried, thus reducing the number of items to be transported during fieldwork. Optical physical quantity measuring devices may also be equipped with an oxygen concentration measuring component. For measuring oxygen concentration, oxygen concentration systems for measuring oxygen concentration in gases, dissolved oxygen systems for measuring oxygen concentration in liquids, pulse oximeters for measuring blood oxygen saturation, etc., may be used. By measuring oxygen concentration with the optical physical quantity measuring device, the number of items to be transported during fieldwork can be reduced. Alternatively, by correcting for oxygen concentration, the error in the emission absorption in the ultraviolet region can be reduced.

[0099] An optical physical quantity measuring device may be equipped with a voice generation component or a voice recording component. By equipping it with a voice generation component, it can generate sound, allowing users to hear instructions on how to use the optical physical quantity measuring device during use, hear the details of the problem in case of an anomaly, or communicate with someone located far from the device. Furthermore, it eliminates the need to carry a separate voice generation device during fieldwork, reducing the number of items carried. An optical physical quantity measuring device may also be equipped with components for storing information other than the physical quantity being measured, and communication components. By equipping it with components for storing information other than the physical quantity, information such as the time, user, and surrounding images can be stored in conjunction with the physical quantity information, and further data utilization such as data linking and searching can be performed. Additionally, by equipping the optical physical quantity measuring device with a communication component, data can be transmitted to a distant data server, or the user of the optical physical quantity measuring device can connect it to other communication devices such as smartphones. Furthermore, the optical physical quantity measuring device can receive information from other communication devices.

[0100] Optical physical quantity measuring devices may be equipped with illumination. Illumination in an optical physical quantity measuring device makes it easier to see the surrounding environment when measuring in dark places. Alternatively, it eliminates the need to carry a separate light source during fieldwork, reducing the number of items carried. Optical physical quantity measuring devices may also be equipped with components for measuring biological data. Examples of biological data include electromyography, electrocardiography, brain waves, blood pressure, blood oxygen saturation, exhaled oxygen saturation, exhaled alcohol concentration, blood alcohol concentration, body temperature, step count, and heart rate. Measuring biological data with an optical physical quantity measuring device eliminates the need to carry a separate device for measuring biological data during fieldwork, reducing the number of items carried. Alternatively, it can be used to manage the health of the user of the optical physical quantity measuring device and can serve as a guideline for undergoing health checkups.

[0101] Optical physical quantity measuring devices may also be equipped with a pressure measuring component. Pressure measuring components include mercury barometers, aneroid barometers, and digital barometers. Measuring atmospheric pressure with an optical physical quantity measuring device eliminates the need to carry a separate pressure measuring component during fieldwork, thus reducing the number of items carried. Optical physical quantity measuring devices have a window, and may further include a window cleaning component. The window is provided to prevent the gas or liquid being measured from coming into contact with the light-emitting or light-receiving part, and cleaning the window with the window cleaning component reduces measurement errors by cleaning the window when it becomes dirty with algae or particles. The window cleaning component may be a brush-scrubbing method or a wiper-cleaning method. By including a window dirt detection component, it is possible to know when the window needs to be replaced.

[0102] The optical physical quantity measuring device may also be equipped with a pump. By equipping the optical physical quantity measuring device with a pump, gases or liquids located some distance away from the device can be transported to the device by suction. In this case, a filter may be provided between the sample collection point and the optical measurement point to remove or reduce foreign matter, particles, or noise-generating substances in the gas or liquid. The optical physical quantity measuring device may also be equipped with a display component. By equipping the optical physical quantity measuring device with a display component, the measurement result can be immediately confirmed by the operator at the measurement point. The display method may include using a component that emits visible light to display the result in color, or it may include displaying text or images.

[0103] Optical physical quantity measuring devices may be equipped with a power supply component. The power supply component may include dry cell batteries or lithium-ion batteries. By equipping an optical physical quantity measuring device with a power supply component, the need to receive power from other power supply devices is eliminated. Furthermore, it is desirable that the electrical path of the power supply component is not exposed to the external environment. The absence of exposed parts reduces the risk of electric shock to the user. This is especially preferable when measuring in aquatic environments such as the sea or rivers to prevent electric shock. Optical physical quantity measuring devices may be equipped with a protective housing. The protective housing may be made of plastic, metal, ceramic, glass, etc. It is preferable to use UV-resistant materials for parts that are irradiated with ultraviolet light, such as the light-emitting part and the sample path. UV-resistant parts may be UV-reflective parts such as aluminum, or UV-transmitting parts such as glass.

[0104] The optical physical quantity measuring device may be equipped with a component that converts seawater or muddy water into drinking water in an emergency. The conversion component may be a filtration membrane, a component that sterilizes water with ultraviolet light, or a component that vaporizes and condenses pure water with heat. The optical physical quantity measuring device may be equipped with a handle for easy carrying. Alternatively, it may be equipped with a component that connects to other equipment or fasteners such as a hook or chain. Furthermore, the weight may be between 10g and 10kg for easy portability, or between 10kg and 1000kg to prevent movement due to wind or waves.

[0105] <Light-emitting section> The light-emitting section emits ultraviolet light with a wavelength of 200 nm or more and less than 240 nm. Specifically, examples include deuterium lamps, krypton-chlorine lamps, tungsten lamps, ultraviolet LEDs, ultraviolet laser diodes, and frequency conversion lasers that convert the wavelength of YAG's fifth harmonic or 460 nm blue laser diode light to 230 nm using an AlN element. Among these, it is preferable to use an LED as the light source because it is small, lightweight, can be turned on and off instantly, can be driven with low power, has a wide emission spectral width, and is inexpensive. The light-emitting section in the embodiment of the present invention may consist of two or more light-emitting sections. The light-emitting section according to this embodiment comprises a plurality of light-emitting sections that emit light with a wavelength of 200 nm or more and less than 240 nm, and the emission output of the first light-emitting section among the plurality of light-emitting sections at each wavelength of 200 nm or more and less than 240 nm is greater than the emission output of all other light-emitting sections among the plurality of light-emitting sections at the same wavelength.

[0106] The following describes an example configuration in which an LED is mounted as a light-emitting part in an optical physical quantity measuring device. The LED comprises a substrate having a first main surface and a second main surface located opposite the first main surface, a first conductivity type semiconductor layer disposed on the first main surface of the substrate, an active layer disposed on the first conductivity type semiconductor layer, a block layer disposed on the active layer, and a second conductivity type semiconductor layer disposed on the block layer.

[0107] (Substrate) The substrate has a first main surface and a second main surface located on the opposite side of the first main surface. The material constituting the substrate is not particularly limited as long as it is possible to arrange a first conductivity type semiconductor layer on the first main surface. Specifically, examples of substrates include aluminum nitride substrates, sapphire substrates, and gallium nitride substrates. In order to make the light emission output of LED1 at wavelengths of 200 nm to less than 240 nm higher than the light emission output of LED2 at wavelengths of 200 nm to less than 240 nm, for example, the substrate used for LED1 and the substrate used for LED2 may be made of different materials. Specifically, an aluminum nitride substrate can be used as the substrate for LED1 and a sapphire substrate can be used as the substrate for LED2.

[0108] To make each LED emit light at wavelengths between 200 nm and 240 nm, it is common to use AlGaN, a mixed crystal of aluminum nitride (AlN) and gallium nitride (GaN), as the material for the light-emitting layer. The difference in lattice constants between the AlGaN used in the active layer and the aluminum nitride used in the substrate is smaller than the difference in lattice constants between the AlGaN used in the active layer and the sapphire used in the substrate. Similarly, the difference in thermal expansion coefficients between the AlGaN used in the active layer and the aluminum nitride used in the substrate is also smaller than the difference in thermal expansion coefficients between the AlGaN used in the active layer and the sapphire used in the substrate. Therefore, in LED 1, which uses aluminum nitride as the substrate, the number of defects generated during thin-film growth of AlGaN can be reduced compared to LED 2, which uses sapphire as the substrate. The number of these defects directly affects the luminous efficiency of the LED and reduces its luminous efficiency. In other words, LED 1, which uses aluminum nitride as the substrate, can have a higher light emission output at wavelengths between 200 nm and 240 nm than LED 2, which uses sapphire as the substrate.

[0109] In the description of the LED embodiment, "B is placed on A" means both a form in which B is placed directly on the surface of A and a form in which B is placed indirectly from the surface of A via another material. For example, even if a first conductivity type semiconductor layer is placed on the substrate via another material (for example, an aluminum nitride (AlN) layer) from the surface of the substrate, and the first conductivity type semiconductor layer is placed indirectly on the substrate, this is also considered to be "the first conductivity type semiconductor layer is placed on the substrate."

[0110] Furthermore, the LED used in the optical physical quantity measuring device of this embodiment may have protrusions or recesses on the second main surface of the substrate in order to improve light extraction efficiency. The protrusions or recesses may be provided directly on the second main surface of the substrate. Alternatively, the protrusions or recesses may be provided on the surface of a layer of a different material provided on the second main surface of the substrate. In other words, the protrusions or recesses may be provided directly or indirectly on the second main surface of the substrate.

[0111] The protrusions may be provided in a variety of shapes and densities, such as cones, pyramidal shapes, hemispherical shapes, and frustums. When the substrate is an aluminum nitride single crystal substrate, it is preferable to include pyramidal shapes with (10-1-1) planes as protrusions, from the viewpoint of achieving a convex shape with high physical and chemical resistance due to stable crystal planes. The size of the protrusions is not particularly limited, but it is preferable that the height is 0.05 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 3 μm or less.

[0112] The recesses may be provided in a variety of shapes and densities, such as cones, pyramidal shapes, hemispherical shapes, and frustum shapes. When the substrate is an AlN single crystal substrate, it is preferable that the recesses include a pyramidal shape with (10-1-1) planes on the sides, from the viewpoint of achieving a recess with high physical and chemical resistance due to stable crystal planes. The size of the recesses is not particularly limited, but it is preferable that the depth be 0.05 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 3 μm or less. When protrusions or recesses are provided on the LED substrate, only protrusions may be provided, only recesses may be provided, or a mixture of protrusions and recesses may be provided. Furthermore, the protrusions may consist of multiple protrusions with different shapes. Similarly, the recesses may consist of multiple recesses with different shapes.

[0113] (First Conductivity Semiconductor Layer) The first conductivity semiconductor layer is a layer that transports electrons or holes to the active layer for converting ultraviolet light into electricity. Here, the first conductivity semiconductor layer means that it is a semiconductor layer exhibiting a different conductivity type than the second conductivity semiconductor layer. That is, if one is a semiconductor layer exhibiting n-type conductivity, the other is a semiconductor layer exhibiting p-type conductivity. The material constituting the semiconductor layer exhibiting n-type conductivity is not particularly limited, but for example, n-AlGaN using Si as an n-type dopant is an example. Similarly, the material constituting the semiconductor layer exhibiting p-type conductivity is not particularly limited, but for example, p-AlGaN using Mg as a p-type dopant is an example. Although not particularly limited, it may be preferable for the first conductivity semiconductor layer to be an n-type semiconductor layer from the viewpoint of crystallinity and surface flatness.

[0114] The material constituting the first conductivity semiconductor layer is not particularly limited as long as it is possible to arrange the active layer on its surface. Examples of specific film compositions for the first conductivity semiconductor layer include AlGaN and GaN. From the viewpoint of arranging a highly crystalline active layer, it is sometimes preferable for the first conductivity semiconductor layer to be n-AlGaN. When n-AlGaN is used as the first conductivity semiconductor layer, it is sometimes more preferable for the Al composition to be 0.70 or more and 1.0 or less from the viewpoint of electrical conductivity and light absorption in the first conductivity semiconductor layer. The Al composition refers to the ratio of Al atoms to the total of Al atoms and Ga atoms. The thickness of the first conductivity semiconductor layer is not particularly limited, but it is sometimes preferable for it to be 300 nm or more and 1.5 μm or less from the viewpoint of driving voltage or crystallinity.

[0115] (Second Conductivity Semiconductor Layer) The second conductivity semiconductor layer is a layer for converting ultraviolet light into electricity. Here, the second conductivity semiconductor layer means a semiconductor layer that exhibits a different conductivity type than the first conductivity semiconductor layer. The material constituting the second conductivity semiconductor layer is not particularly limited as long as it can be placed on the active layer. Examples of specific film compositions for the second conductivity semiconductor layer include AlN, GaN, AlGaN, InN, and mixed crystals thereof. From the viewpoint of electrical conductivity and contact resistance, the second conductivity semiconductor layer may preferably be p-AlGaN. The thickness of the second conductivity semiconductor layer is not particularly limited, but from the viewpoint of achieving high optical output, it is preferably 5 nm to 1000 nm, and more preferably 15 nm to 200 nm. The second conductivity semiconductor layer may contain impurities such as C, H, Si, and Mg. The types of impurities are not limited to these.

[0116] (Active layer) The active layer is Al ｘ Ga １－ｘ A quantum well layer composed of N and Al ｙ Ga １－ｙIt has a multiple quantum well structure in which barrier layers composed of N (y > x) are repeatedly stacked with N periods (where N is a natural number). The active layer functions as part of the light-emitting part of the LED. In general, among the repeating structures of a multiple quantum well structure, the layer with the smaller band gap is called the quantum well layer or simply the well layer, and the layer with the larger band gap is called the barrier layer. ｙ Ga １－ｙ The thickness of the N layer (y > x) is not particularly limited, but from the viewpoint of internal quantum efficiency, it may be preferable to have a thickness of 1 nm to 20 nm.

[0117] To make the emission output of LED1 at wavelengths between 200 nm and 240 nm higher than that of LED2 at wavelengths between 200 nm and 240 nm, the structure of the quantum well layer of LED1 and the quantum well layer of LED2 may be changed. The emission wavelength of an LED is largely influenced by the Al composition x and film thickness t [nm] of the quantum well layer. There are many combinations of Al composition x and film thickness t that result in the same emission peak wavelength for the LEDs, and the luminous efficiency of the LED can be changed by changing the combination of Al composition x and film thickness t. In other words, it is possible to create different versions of LED1 and LED2 by changing the Al composition x and film thickness t values ​​of the quantum well layer.

[0118] (Blocking Layer) The LED used in the optical physical quantity measuring device of this embodiment may further include a blocking layer between the active layer and the second conductivity semiconductor layer, from the viewpoint of blocking carriers (electrons or holes) injected from the first conductivity semiconductor and allowing more carriers to be injected into the active layer. When the carriers injected from the first conductivity semiconductor layer are electrons, this blocking layer is also called an electron blocking layer. When the carriers injected from the first conductivity semiconductor layer are holes, this blocking layer is also called a hole blocking layer. The blocking layer may be made of, for example, Al ｂ Ga １－ｂ It is composed of N (b > x). The rate of carrier overflow into the second conductivity type semiconductor layer depends on the Al composition b or film thickness t2 of the block layer. In other words, the Al that constitutes the block layer ｂ Ga １－ｂBy changing the Al composition b of N and the thickness t2 of the block layer, it is possible to create LED1 and LED2 separately.

[0119] (Electrodes) The LED used in the optical physical quantity measuring device of this embodiment may be equipped with electrodes to efficiently inject electrons and holes into the active layer. The electrodes are not particularly limited, but may be a first electrode electrically connected to a first conductivity type semiconductor layer and a second electrode electrically connected to a second conductivity type semiconductor layer. It is preferable that the electrodes are ohmic connected to the layers with which they are in physical contact. Examples of materials constituting the first electrode or the second electrode include metals such as Al, Au, Ti, Ni, Va, Cr, Rh, Mo, Pt, and Ta, or mixed crystals thereof.

[0120] (Insulating layer) The LED used in the optical physical quantity measuring device according to this embodiment may have at least a portion of its surface covered with an insulating layer from the viewpoint of reliability. The material of the insulating layer is not particularly limited, but examples include silicon oxide, silicon nitride, and aluminum oxide.

[0121] <Light Receiving Section> The light receiving section receives ultraviolet light with a wavelength of 200 nm or more and less than 240 nm. Specifically, this includes photodiodes made of Si or AlGaN, phototransistors made of Si or AlGaN, gas discharge sensors, fluorescence sensors that measure the fluorescence of ultraviolet light, and spectrometers. Among these, it is preferable to use a photodiode as the light receiving element because it is small, lightweight, can be driven with low power, has a wide light-receiving spectral width, and is inexpensive. There may be one light receiving section, two light receiving sections, or more than two light receiving sections.

[0122] An optical physical quantity measuring device may or may not have a filter that attenuates ultraviolet light in the direction of emission. To achieve miniaturization and cost reduction of the optical physical quantity measuring device, it is preferable to omit the filter. The filter may cut out harmful light in the deep ultraviolet region having a specific range of wavelengths. The filter may be a wavelength-selective filter. The filter may transmit light with wavelengths between 200 nm and 240 nm, and block light with wavelengths below 200 nm and above 240 nm. The filter may transmit light with wavelengths between 200 nm and 235 nm, and block light with wavelengths below 200 nm and above 235 nm. The filter may transmit light with wavelengths between 200 nm and 230 nm, and block light with wavelengths below 200 nm and above 230 nm. The filter may be, for example, a dielectric multilayer filter. The filter may be, for example, HfO ２ Layers and SiO ２ It may also be a dielectric multilayer filter having layers, SiO ２ Layer and Al ２ O ３ It may also be a dielectric multilayer filter having layers.

[0123] <Memory Unit> The optical physical quantity measuring device may have a memory unit for storing the amount of ultraviolet light emitted. The memory unit may store irradiation time or emission output set so that the amount of light emitted from each LED meets a predetermined irradiation standard. These irradiation times or emission outputs may be set so that the amount of irradiation meets the predetermined irradiation standard, taking into account the individual differences of each LED and filter. When the memory unit stores the emission output set in this way, it may also store the irradiation time specified in advance by the administrator or manufacturer of the optical physical quantity measuring device along with the emission output.

[0124] Here, the "irradiation standard" in this embodiment may be a standard defined by, for example, ACGIH (American Conference of Governmental Industrial Hygienists), JIS C7550, or BEI (Biological Exposure Indices). By using the ACGIH standard for the optical physical quantity measuring device, it is possible to prevent users of the optical physical quantity measuring device from being mistakenly exposed to an amount exceeding the standard value from the light emission part. According to the ACGIH standard, first, the cumulative effective irradiance (Eeff) is calculated by integrating the value obtained by multiplying the irradiation intensity (Eλ) for each wavelength by the relative spectral effect value (S value). Then, the product of this cumulative effective irradiance (Eeff) and time (texp) is 3 mJ / cm² for 8 hours of use per day. ２ It is stipulated that the amount used should not exceed a certain limit. The irradiation intensity (Eλ) for each wavelength of light and its safety for the human body are not one-to-one; even a 1 nm difference in wavelength can change the level of harmfulness. Therefore, the S value is used as a correction value when the level of harmfulness changes. In other words, for each wavelength, the irradiation intensity (Eλ) at that wavelength is multiplied by the S value at that wavelength, and the result is integrated over a predetermined wavelength width Δλ (for example, 1 nm) to represent the cumulative effective illuminance, which indicates the level of safety for the human body. The S value varies greatly depending on the wavelength. If the emission wavelength of the light source deviates from the design value, and the emission spectrum shifts to a shorter or longer wavelength side than the reference emission spectrum, the level of harmfulness will be 3 mJ / cm² with 8 hours of use per day. ２The usable time will vary to avoid exceeding the limit. Light in the wavelength range of 200 nm to less than 240 nm exhibits large changes in S value, and if the emission spectra of multiple LEDs mounted on an optical physical quantity measuring device are different, the emission spectrum of the optical physical quantity measuring device equipped with multiple LEDs may deviate from the expected value. For this reason, in order to meet the standards specified by ACGIH, JIS C7550, BEI, etc., it is preferable to combine LED1 and LED2 such that the emission output of LED1 at each wavelength in the wavelength range of 200 nm to less than 240 nm is greater than the emission output of LED2 at the same wavelength. This is effective in further reducing the probability of the optical physical quantity measuring device becoming a defective product.

[0125] The optical physical quantity measuring device may have a function to detect the presence of a substance in a region facing the optical physical quantity measuring device. The optical physical quantity measuring device may, for example, prevent ultraviolet light from being emitted in a region facing the optical physical quantity measuring device if a substance is present in that region. Specifically, the optical physical quantity measuring device may have a human presence sensor that detects whether a person is present in the direction of the light emitted from the optical physical quantity measuring device, and a proximity sensor that detects whether a substance is present in a region within a predetermined distance in the direction of the light emitted from the optical physical quantity measuring device.

[0126] Furthermore, the optical physical quantity measuring device may have a function to recognize the presence of a substance by receiving a signal emitted by another device that detects the presence of a substance and is positioned separately from the optical physical quantity measuring device when that device detects the presence of a substance. For example, as another device, a camera with an image recognition processing unit that images the area facing the optical physical quantity measuring device and performs image recognition processing may be provided. The optical physical quantity measuring device may receive a signal indicating the approach of a substance transmitted from the camera when image recognition processing is performed on the image of the area facing the optical physical quantity measuring device captured by the camera and the approach of a substance is detected. Furthermore, as another device, a carbon dioxide concentration measuring device that measures the concentration of carbon dioxide in a closed or semi-closed space may be provided. The optical physical quantity measuring device may receive a signal indicating the presence of an animal transmitted from the carbon dioxide concentration measuring device when the presence of an animal is detected when the carbon dioxide concentration exceeds a predetermined value.

[0127] <Control Unit> The optical physical quantity measuring device may have a control unit that controls the power supply to each light-emitting unit. The control unit may have a timer. For example, in response to a signal input from the sensor described above, the control unit may read a preset irradiation time or a preset light emission output and a specified irradiation time from the memory unit and output a start signal to the power supply unit to start the optical measurement. In response to the elapsed preset irradiation time or specified irradiation time, or in response to the sensor ceasing to input a signal or receiving any other different signal as described above before these irradiation times have elapsed, the control unit may output an end signal to the power supply unit to turn off the power to the optical physical quantity measuring device when the optical physical quantity measuring device detects the presence of a substance, thereby preventing the emission of ultraviolet light.

[0128] Furthermore, the control unit may control the emission of ultraviolet light when it detects the presence of a substance. For example, the optical physical quantity measuring device has a shutter located in the ultraviolet light emission unit, and the control unit may control the shutter to close when the optical physical quantity measuring device detects the presence of a substance, thereby preventing the emission of ultraviolet light to the outside. Alternatively, the optical physical quantity measuring device may have a mechanism to change the direction in which ultraviolet light is emitted from the ultraviolet light emission unit, and the control unit may control the direction of ultraviolet light irradiation when the optical physical quantity measuring device detects the presence of a substance, thereby preventing the detected substance from being irradiated with ultraviolet light.

[0129] Furthermore, the optical physical quantity measuring device may have a control unit that controls the device to transmit a signal to the outside indicating that it has detected the presence of a substance when it detects the presence of a substance. For example, the optical physical quantity measuring device may have a function that, when it detects the presence of a substance, emits one or more of the following to draw the attention of people in the vicinity: visible light emission, sound, smell, vibration, heat, cold, wind, etc. The optical physical quantity measuring device may also have a display unit that displays text to draw the attention of people in the vicinity when it detects the presence of a substance.

[0130] An optical physical quantity measuring device may be used independently or as a component incorporated into other devices. Examples of other devices into which an optical physical quantity measuring device may be incorporated include, for example, drones that float in the air, autonomous robots that clean floors, electrical appliances such as refrigerators and humidifiers, airplanes, and trains. An optical physical quantity measuring device incorporated into other devices may be mounted in a position that allows ultraviolet light to be irradiated to the outside of the device, or in a position that allows ultraviolet light to be irradiated to the inside of the device. Specifically, an optical physical quantity measuring device incorporated into a drone or an autonomous robot that cleans floors may be mounted in a position that allows ultraviolet light to be irradiated to the outside of the device, and ultraviolet light may be irradiated to the optical path outside the device. In addition, an optical physical quantity measuring device incorporated into electrical appliances such as refrigerators and humidifiers, airplanes, and trains may have the ultraviolet light path limited to the inside of the device. An optical physical quantity measuring device may be used individually or multiple identical optical physical quantity measuring devices may be installed.

[0131] When an LED is used in the light-emitting part, the physical quantities of each layer are measured as follows: (Film Thickness Measurement) The film thickness of each layer of the light-emitting diode in the embodiment can be measured by cutting out a predetermined cross section perpendicular to the first main surface of the substrate, observing this cross section with a transmission electron microscope (TEM), and using the TEM length measurement function. As for the measurement method, first, a cross section perpendicular to the first main surface of the nitride semiconductor element substrate is observed using the TEM. Specifically, for example, the observation width is set to a range of 2 μm or more in the direction parallel to the first main surface of the substrate in the TEM image showing a cross section perpendicular to the first main surface of the nitride semiconductor element substrate. Within this observation width range, contrast is observed at the interface of two layers with different compositions, so the thickness up to this interface is observed in a continuous observation area with a width of 200 nm. The average value of the thickness of each layer included in this 200 nm wide observation area is calculated from five locations arbitrarily extracted from the observation width of 2 μm or more as described above, thereby obtaining the film thickness of each layer.

[0132] (Composition Measurement) The composition of each layer of the light-emitting diode in the embodiment can be measured by reciprocal space mapping (RSM) using X-ray diffraction (XRD). Specifically, the Al composition can be obtained by analyzing the reciprocal space mapping data near the diffraction peak obtained using the asymmetric plane as the diffraction plane. Examples of diffraction planes include the (10-15) plane and the (20-24) plane. Furthermore, for layers such as the quantum well layer and the first composition gradient layer, where sufficient reflectance cannot be obtained by XRD, the composition can be measured by X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), and electron energy loss spectroscopy (EELS).

[0133] In EELS, the composition of a sample is analyzed by measuring the energy lost when an electron beam passes through the sample. Specifically, for example, in a thinned sample used for TEM observation, the energy loss spectrum of the intensity of the transmitted electron beam is measured and analyzed. By utilizing the fact that the peak position of the peak that appears around 20 eV of energy loss changes according to the composition of each layer, the composition can be determined from the peak position. Similar to the layer thickness calculation method using TEM observation described above, the Al composition of each layer is obtained by calculating the average value of the Al composition in an observation width of 200 nm from five locations arbitrarily extracted from an observation area of ​​2 μm or more. In EDX, characteristic X-rays generated by the electron beam are measured and analyzed in a thinned sample used for TEM observation, as described above. Similar to the layer thickness calculation method using TEM observation described above, the Al composition of each layer is obtained by calculating the average value of the Al composition in an observation width of 200 nm from five locations arbitrarily extracted from an observation area of ​​2 μm or more.

[0134] XPS allows for depth-direction evaluation by performing XPS measurements while sputter etching using an ion beam. Ar+ is generally used as the ion beam, but other ion species such as Ar cluster ions can be used as long as they can be irradiated by the etching ion gun mounted on the XPS apparatus. The depth-direction distribution of the Al composition in each layer is obtained by measuring and analyzing the XPS peak intensities of Al, Ga, and N. Instead of sputter etching, the light-emitting diode can be obliquely polished so that a cross section perpendicular to the first main surface of the substrate is magnified and exposed, and the exposed cross section can be measured with XPS.

[0135] The composition of each layer can be measured not only by XPS but also by Auger electron spectroscopy (AES). In this case, the composition can be measured by performing Auger electron spectroscopy on a cross-section exposed by sputter etching or oblique polishing. Furthermore, the composition of each layer can also be measured by SEM-EDX (Scanning Electron Microscope-Energy Dispersive X-ray spectroscopy) measurement on a cross-section exposed by oblique polishing. The number of repeating periods of the multiple quantum well structure of the light-emitting diode in the embodiment is defined by the number of quantum well layers and can be measured by TEM observation in the same manner as described above.

[0136] (Measurement of Emission Spectrum) The emission wavelength from the light-emitting part of the embodiment can be calculated by measuring the emission spectrum emitted when an electric current is passed through it. The emission peak wavelength is the wavelength at which the emission output is maximized in the emission spectrum. The following explanation will use the case where an LED is used as the light-emitting part as an example. To measure the emission spectrum of LED1 or LED2 after fabricating the optical physical quantity measuring device, the tip of a fiber connected to the spectrometer can be brought close to the vicinity of LED1 or LED2, and the emission from LED1 or LED2 can be received to perform the measurement.

[0137] <Calculation Unit> The calculation unit may calculate at least two physical quantities of a substance based on the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit, which are acquired by the acquisition unit. In this embodiment, up to N physical quantities can be calculated from N measured values. As a calculation method, for example, absorbance A calculated based on the Lambert-Beer equation (1) shown below can be used. In equation (1), I １ I is the measured value measured by the light receiving unit when the object to be measured is in the optical path. ０ The optical path contains a reference sample (for example, water if the substance being measured is in water, or a gas composed of 21% oxygen and 79% nitrogen if the substance is in the atmosphere).

[0138]

[0139] An example of an embodiment is described below. As shown in Figure 6(a), the optical physical quantity measuring device according to the embodiment includes LEDs 1, 2, 3, and 4 (first light-emitting unit, second light-emitting unit, third light-emitting unit, and fourth light-emitting unit) with peak wavelengths of 215 nm, 235 nm, 265 nm, and 450 nm. It also includes photodiodes for receiving the emitted light, with sensors a, b, c, and d (first light-receiving unit, second light-receiving unit, third light-receiving unit, and fourth light-receiving unit) having higher light-receiving sensitivity at wavelengths of 215 nm, 235 nm, 265 nm, and 450 nm, respectively. LEDs 1, 2, 3, and 4 are positioned opposite sensors a, b, c, and d, respectively, so that the light emitted from LEDs 1, 2, 3, and 4 can be received by sensors a, b, c, and d, respectively.

[0140] When the light emitted from LEDs 1, 2, 3, and 4 is received by sensors a, b, c, and d, the absorbance Axy (x = 1, 2, 3, 4, y = a, b, c, d) is calculated based on equation (1). The measurement target is NO in the atmosphere. ２ In this case, since it absorbs light below 250 nm, A1a, A2a, A1b, and A2b are NO ２ Different values ​​are calculated depending on the concentration. A3a, A4a, A3b, A4b, A1c, A2c, A3c, A4c, A1d, A2d, A3d, A4d are NO ２ It is calculated with a value that does not change with respect to the concentration of NO. ２ Since the absorption coefficient is greater at 215 nm than at 235 nm, A1a < A1b and A2a < A2b. Here, NO has an ultraviolet absorption coefficient below 250 nm. ３ And, NH with an ultraviolet absorption coefficient of 220 nm or less ３ If it is present as an impurity, A1a (NO ２ And NO ３ (absorbed) and A2a (NO ２ And NO ３ and NH ３ By performing operations such as the difference, division, or combination of arithmetic operations on two numbers (which are absorbed), NH ３ The concentration can be calculated. Furthermore, by adding the two values ​​A1b and A2b and performing arithmetic operations, NO ２ NO ３The concentration of NH can be calculated. ３ NO ２ NO ３ This is because it has different absorption coefficients for each wavelength of ultraviolet light.

[0141] Furthermore, by adding the values ​​of A3y and Axc calculated from the measurement of LED3 or sensor c to the calculation process, the concentrations of volatile organic compounds that absorb at a wavelength of 265 nm, such as toluene and xylene, and organic compounds in water such as amino acids and fatty acids can also be calculated, and NO ２ NO ３ NH ３ This improves the accuracy and precision of concentration measurement. Furthermore, by adding the values ​​of A4y and Axd calculated from the measurement of LED4 or sensor d to the calculation process, it is possible to measure light attenuation due to foreign matter such as particles, NO ２ NO ３ NH ３ This improves the accuracy and precision of concentration measurements. Thus, while the conventional method shown in Figure 6(b), which places one sensor opposite one LED, limits the number of measurement values ​​to four, by using multiple combinations between the LED and sensor, this example allows for obtaining up to 16 measurement values, and also allows for calculating up to 16 physical quantities.

[0142] In this example, the number of measured values ​​was increased by changing the combination of LEDs and sensors. However, it is also possible to increase the number of measured values ​​by changing the distance between the LEDs and sensors, changing the orientation of the LEDs and sensors (this will change the measured values ​​due to the light distribution and reception distribution), simultaneously receiving the light emitted from one or more LEDs with one or more sensors, or receiving the light in segments with a time difference or shutter, or controlling the amount of light emitted by the LEDs or the amount of light received by the sensors with a filter.

[0143] Furthermore, when measuring the intensity of each wavelength in the emission spectrum from the LED at the light receiving unit, the number of measurement values ​​can be increased according to the number of wavelengths being measured. The spectral width can also be used as the measurement value. Additionally, the drive current and drive time (pulse width in the case of pulse measurement) of the LED and light receiving element may be changed. In this case, the number of measurement values ​​can be increased. Also, measurements between LED1 and sensor a may be performed sequentially, followed by measurements between LED1 and sensor b, or measurements of other combinations, or they may be performed simultaneously. When performed sequentially, the timing of the LED and sensor drives may be staggered, separated by a shutter, or measurements may be made possible by the movement of the LED or sensor.

[0144] <System> As an example of a solution, by using the optical physical quantity measuring device according to this embodiment, input power can be fed back to the catalytic resource utilization associated with the component analysis of exhaust gas, and power consumption in the sewage treatment system associated with the component analysis of wastewater can be reduced.

[0145] While embodiments of the present disclosure have been described above, these embodiments are merely illustrative examples of devices and methods for realizing the technical concept of the present disclosure, and the technical concept of the present disclosure does not specify the material, shape, structure, arrangement, etc., of the components. The technical concept of the present disclosure can be modified in various ways within the technical scope defined by the claims described in the patent claims.

[0146] 1-4 LED a-d Sensor

Claims

1. An optical physical quantity measuring device comprising a plurality of light-emitting units that emit light with a wavelength of 200 nm or more and less than 240 nm, wherein the emission output of the first light-emitting unit among the plurality of light-emitting units at each wavelength of 200 nm or more and less than 240 nm is greater than the emission output of all other light-emitting units among the plurality of light-emitting units at the same wavelength.

2. An optical physical quantity measuring device comprising a plurality of light-emitting units that emit light with a wavelength of at least 200 nm or more and less than 240 nm, wherein the emission output of the first light-emitting unit among the plurality of light-emitting units at each wavelength between 240 nm and 280 nm is greater than the emission output of all other light-emitting units among the plurality of light-emitting units at the same wavelength.

3. The optical physical quantity measuring device according to claim 1 or 2, wherein the emission peak wavelength of the first light-emitting unit is greater than the emission peak wavelengths of all other light-emitting units among the plurality of light-emitting units.

4. The optical physical quantity measuring device according to claim 3, wherein the emission peak wavelength of the first light-emitting part is 200 nm or more and less than 240 nm.

5. The optical physical quantity measuring device according to claim 3, wherein the first light-emitting unit emits only light with a wavelength of 220 nm or longer.

6. The optical physical quantity measuring device according to claim 5, wherein the relative value calculated by dividing the light emission output obtained by integrating the light emission output at each wavelength in the wavelength range of 220 nm to less than 230 nm of the first light-emitting unit by the light emission output obtained by integrating the light emission output at each wavelength in the wavelength range of 220 nm to less than 230 nm of any of the plurality of light-emitting units other than the first light-emitting unit is smaller than the relative value calculated by dividing the light emission output obtained by integrating the light emission output at each wavelength in the wavelength range of 230 nm to less than 240 nm of the first light-emitting unit by the light emission output obtained by integrating the light emission output at each wavelength in the wavelength range of 230 nm to less than 240 nm of any of the light-emitting units.

7. The optical physical quantity measuring device according to claim 1, wherein the emission output of the second emission unit, which is an emission unit other than the first emission unit among the plurality of emission units, at each wavelength between 200 nm and 240 nm is smaller than the emission output of all other light-emitting diodes at the same wavelength.

8. An optical physical quantity measuring device according to claim 1 or 2, comprising: a first light receiving unit that receives at least a portion of the light emitted by the first light-emitting unit; a second light receiving unit that receives at least a portion of the light emitted by at least one light-emitting unit from among the plurality of light-emitting units that is different from the first light-emitting unit; and an acquisition unit that acquires the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit.

9. An optical physical quantity measuring device according to claim 8, and an optical physical quantity measuring system comprising: a calculation unit that calculates physical quantities of at least two substances based on the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit acquired by the acquisition unit.

10. An optical physical quantity measuring device according to claim 8, and a storage unit that stores the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit, acquired by the acquisition unit.

11. An optical physical quantity measurement system according to claim 10, comprising: a calculation unit that calculates at least two physical quantities of a substance based on the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit, wherein the calculation result of the calculation unit is stored in the storage unit.

12. The optical physical quantity measuring system according to claim 11, wherein the storage unit is provided outside the optical physical quantity measuring device, and the calculation unit is configured to be able to write to and read from the storage unit.

13. A method for manufacturing an optical physical quantity measuring device, comprising selecting a plurality of light-emitting units that emit light at wavelengths of 200 nm to less than 240 nm, including the first light-emitting unit, such that the emission output of the first light-emitting unit at each wavelength between 200 nm and less than 240 nm is greater than the emission output of all other light-emitting units at the same wavelength, and equipping the selected plurality of light-emitting units.

14. A method for manufacturing an optical physical quantity measuring device according to claim 13, wherein a group of first light-emitting units including a plurality of the first light-emitting units and a group of second light-emitting units including a plurality of second light-emitting units whose light emission output at each wavelength between 200 nm and 240 nm is always smaller than the light emission output at the same wavelength of any light-emitting unit in the group of first light-emitting units are stored separately in advance.

15. An optical physical quantity measuring device comprising: a first light-emitting unit and a second light-emitting unit whose light emission output at each wavelength between 200 nm and 240 nm is smaller than the light emission output of the first light-emitting unit at the same wavelength, comprising: acquiring the light emission output of the first light-emitting unit at each wavelength between 200 nm and 240 nm; calculating and acquiring a maximum luminescence potential value, which is the maximum value that the integrated light emission output of the optical physical quantity measuring device at wavelengths between 200 nm and 240 nm can take, based on the light emission output of the first light-emitting unit; and determining that the optical physical quantity measuring device is a good product if the maximum luminescence potential value does not exceed an allowable upper limit, which is a predetermined upper limit of light emission output as a good product standard.

16. The method for inspecting an optical physical quantity measuring device according to claim 15, wherein acquiring the light emission output of the first light-emitting unit comprises: measuring the light emission output of the first light-emitting unit; creating primary data based on the measured light emission output of the first light-emitting unit; and estimating the light emission output for each wavelength of the optical physical quantity measuring device using only the primary data of the first light-emitting unit.

17. An optical physical quantity measuring device comprising: a first light-emitting unit and a second light-emitting unit whose light emission output at each wavelength between 200 nm and 240 nm is smaller than the light emission output of the first light-emitting unit at the same wavelength, wherein the method for inspecting an optical physical quantity measuring device comprises: acquiring the light emission output of the second light-emitting unit at each wavelength between 200 nm and 240 nm; calculating and acquiring a minimum luminescence probability value, which is the minimum value that the integrated light emission output of the optical physical quantity measuring device can take in the wavelength region between 200 nm and 240 nm, based on the light emission output of the second light-emitting unit; and determining that the optical physical quantity measuring device is a good product if the minimum luminescence probability value does not fall below an allowable lower limit value, which is a predetermined lower limit value of light emission output set as a standard for good products.

18. The method for inspecting an optical physical quantity measuring device according to claim 17, wherein acquiring the light emission output of the second light-emitting unit comprises: measuring the light emission output of the second light-emitting unit; creating primary data based on the measured light emission output of the second light-emitting unit; and estimating the light emission output for each wavelength of the optical physical quantity measuring device using only the primary data of the second light-emitting unit.

Images