JP4127195B2 - Spectral intensity measuring device and calibration method thereof, spectral reflection characteristic measuring device and calibration method thereof - Google Patents

Description

  The present invention relates to a device for measuring the spectral intensity distribution of light to be measured and the spectral reflection characteristics of a sample to be measured, and a calibration method thereof, and more particularly to correction of humidity drift in these photometric circuits.

  A polychromator that measures the spectral intensity of all wavelengths in the measurement wavelength range at the same time has a high measurement efficiency and can measure instantaneous light. ) And spectral means of a spectrocolorimeter (spectral reflection characteristic measuring device) for measuring the spectral reflection characteristic of a sample. FIG. 6 is a cross-sectional view showing a schematic configuration of a general polychromator 1. The polychromator 1 includes an incident aperture 3 disposed in a housing 2, a light receiving sensor array 4, a diffraction grating 5 that creates a chromatic dispersion image of the incident aperture 3 by a light beam passing through the incident aperture 3 on the light receiving sensor array 4, and The imaging optical system 6 is comprised.

  Here, the light receiving sensor array 4 is roughly classified into a scanning sensor array such as a CCD and a CMOS, and a non-scanning silicon photodiode array. The scanning sensor array sequentially reads the photocurrent of each sensor accumulated in the capacitor and processes the output signals of all the pixels with a single detection circuit, so that the processing circuit can be reduced in size and size. There is a merit. However, because it is inferior in terms of performance such as noise, dynamic range, and linearity, when high sensitivity and high performance are required, a processing circuit is required for each sensor, but a silicon photodiode array is used. There are many cases.

  FIG. 7 shows a configuration example of the processing circuit 11 corresponding to the silicon photodiode array. The processing circuit 11 includes current-voltage conversion circuits A1, A2,..., An arranged for each of pixel sensors (photodiodes) of a plurality of channels CH1, CH2,. Multiplexer 12 that alternatively and sequentially selects outputs A1 to An, gain variable amplifier 13 that amplifies the output from multiplexer 12, and analog / digital conversion that performs analog / digital conversion of the output from gain variable amplifier 13 And a container 14.

  The current-voltage conversion circuits A1 to An have resistance values of the feedback resistors RF1 to RFn, and therefore have different gains, and have high performance in the noise, dynamic range, linearity, etc., and the high sensitivity (measured to low luminance). High performance has been realized. However, in such a configuration, the sensitivity of the photodiode is low (photocurrent obtained by photoelectric conversion is small even with the same incident light amount), and on the short wavelength side, the feedback resistors RF1 to RFn are often several hundred MΩ. Are used, and the current-voltage conversion circuits A1 to An have high gain.

Here, FIG. 8 shows an example of a general current-voltage conversion circuit 21 that converts the photocurrent generated by the photodiode into a voltage. The current-voltage conversion circuit 21 includes an operational amplifier A and a feedback resistor Rf, and outputs a voltage Vo = Ip * Rf corresponding to the photocurrent Ip. In order to detect the minute photocurrent Ip as described above, a high resistance of 10 ⁸ Ω is often used as the feedback resistor Rf. In that case, the influence of the leakage resistance between the substrate patterns, which is often about 10 ¹¹ Ω, cannot be ignored. The main influence is the leakage current I1 flowing from the external voltage source Ve to the input terminal of the operational amplifier A through the leakage resistance Ri and the leakage resistance Rf ′ connected in parallel to the feedback resistance Rf. Considering these, the output voltage Vo is expressed as follows.

Vo = (Ip + I1) * (Rf + Rf ′)
= Ip * (Rf + Rf ′) + I1 * (Rf + Rf ′)
Here, the second term is the contribution of the leakage current I1, and by subtracting the dark output Vd = I1 * (Rf + Rf ′) when the incident light is blocked (Ip = 0), the influence is avoided as follows. be able to.

Vo ′ = Vo−Vd = Ip * (Rf + Rf ′) = Ip * Rf + Ip * Rf ′
However, the influence of the leak resistance Rf ′ appears as a change in the gain of the circuit, and the error Ip * Rf ′ due to this is proportional to the photocurrent Ip (incident light amount) and cannot be easily corrected. The leak resistance Rf ′ changes with humidity and causes a gain fluctuation, for example, in units of several minutes, so that accuracy as well as stability is impaired. Recent miniaturization of parts and refinement of substrate patterns have reduced the leakage resistance Rf ′, and its influence tends to increase. Especially in portable devices that are required to be used in a wide range of environmental conditions including outdoors. , It becomes a big problem.

Then, as a prior art which solves such a problem, the following is mentioned, for example.
1. The feedback resistance Rf is reduced.
2. Use large-sized parts and ensure sufficient distance between patterns.
3. As shown in Non-Patent Document 1, in FIG. 8, a guard pattern GP is applied so as to surround the connection point P having a high potential, and the potential difference from the substrate is eliminated by virtual grounding.
4). Apply a moisture resistant coat to the substrate.
OP Amplifier IC Utilization Know-how (Toshio Tamamura, iQ Publishing, Field Engineer Practical Series p153-155)

  The method 1 has a problem that the sensitivity described above is sacrificed. Further, the method 2 has a problem that the product value is lowered at the expense of downsizing.

  Although the method 3 has been relatively effective in the past, it is becoming difficult with the miniaturization of parts and the refinement of patterns. Further, when the substrate surface is dirty, there is a problem that the effect is lowered.

  Specifically, the above-mentioned method 4 accumulates and forms a high-density film that does not allow moisture to pass through, for example, vacuum deposition, so that a high effect can be obtained, but there is a problem that a considerable cost increase is involved. There is.

  An object of the present invention is to provide a low-cost spectral intensity measurement device, a calibration method thereof, a spectral reflection characteristic measurement device, and a calibration method thereof that can maintain the accuracy by correcting the gain change due to humidity. It is to be.

In the spectral intensity measuring device of one aspect of the present invention, the light to be measured is separated into a plurality of wavelength components by the wavelength separating unit, and received by the plurality of light receiving units, respectively, and the spectral intensity of each wavelength component is obtained. In a spectral intensity measurement device called a spectral luminance meter, correction illumination means for illuminating each light receiving means during calibration, and during the calibration, the correction illumination means is lit and output from each illuminated light receiving means result of the level calculated with correction coefficients set in the respective light receiving means, calibrates the correction coefficient to match the reference value stored in advance, at the time of measurement was calibrated output level from the light receiving means And a calculation control means for calculating a correction coefficient and calculating a spectral intensity of each wavelength component.

  According to the above configuration, when calibrating a spectral intensity measuring apparatus in which the light to be measured is separated into a plurality of wavelength components by the wavelength separating means and the spectral intensity of each wavelength component is obtained by the plurality of light receiving means, The intensity measuring device separates the light to be measured into a plurality of wavelength components by the wavelength separation means and measures to a low luminance. For example, as an output from a light receiving means comprising a photodiode and a current-voltage conversion circuit. In this case, a weak photocurrent is amplified by a high gain amplifier. Therefore, the leakage resistance due to humidity is formed and influenced by the high gain for obtaining the desired sensitivity, particularly the feedback resistance. The resistance value of the leak resistance varies depending on the humidity.

For this reason, in the above invention, in order to correct the output level from each light receiving means, a correction coefficient is set in each light receiving means, and in the calculation control means, the output level from each light receiving means is set to the correction coefficient, for example. To correct the humidity. Then, in order to calibrate the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, and each of the obtained result of output level from the light receiving means and calculating a correction coefficient set in each light receiving means, by calibrating the correction coefficient to match the reference value stored in advance, the leakage resistance at that time Correct the gain shift caused by. Then, when the actual measurement, and calculates its calibrated correction factor and output level from the light receiving means, obtaining the spectral intensity of each wavelength component.

  Therefore, the correction of the humidity drift of the spectral intensity measuring device can be realized simply and at low cost by providing the correction illumination means and partially changing the measurement sequence. In this way, gain change due to humidity can be corrected, and accuracy can be maintained under a wide range of environmental conditions. This is particularly effective for portable devices that are required to be used outdoors.

  In the above invention, the incident light to the sensor array which is the forefront of the processing system is used as an input signal, and the gain is corrected based on the digital signal output that has been subjected to signal processing and analog / digital conversion. Gain fluctuation caused by all the elements of the processing system between output signals can be corrected in a lump, and even if the fluctuation element is an amplification system following the current-voltage converter circuit, the reference voltage of the analog / digital converter Even if the fluctuation factor is not humidity but temperature and time-dependent, it can be corrected effectively together as long as there is no change in the gain of the monitor light receiving means and the processing system at the later stage. it can.

  In addition, the spectral intensity measuring apparatus according to another aspect of the present invention provides a monitor light receiving unit that is adjacent to the light receiving unit and has a smaller gain variation than the light receiving unit for monitoring illumination light from the correction lighting unit. The calculation control means relativizes the correction output obtained from the plurality of light receiving means with the output of the monitor light receiving means.

  According to the above configuration, the monitoring light receiving means is provided adjacent to the light receiving means for monitoring the illumination light from the correction lighting means, the gain of the subsequent amplifier is increased, and the resistance value of the feedback resistor The monitor light-receiving means reduces the gain fluctuation even when the gain of the monitoring light-receiving means is similar to that of the plurality of light-receiving means.

  Therefore, the monitor light receiving means detects a change in correction illumination light intensity from the correction illumination means due to aging, etc., and further makes the correction output from each light receiving means relative to the output of the monitor light receiving means. By doing so, it is possible to more accurately set the correction coefficient for canceling the change and correcting the humidity drift. Moreover, even if the fluctuation factor is the replacement of the processing system parts in the repair or production process, it is automatically made as long as there is no change in the gain of the light receiving means for monitoring and the subsequent processing system because of the relative relationship. It can be corrected.

  Furthermore, the spectral intensity measuring device according to another aspect of the present invention increases the gain of the amplifier at the subsequent stage of the monitor light receiving means, and sets the resistance value of the feedback resistor of the current-voltage conversion circuit in the monitor light receiving means, It is characterized by being 1 MΩ or less.

  According to the above configuration, in order to realize the high gain, the gain of the amplifier at the subsequent stage of the light receiving means for monitoring is increased with respect to the resistance value of the feedback resistance of each light receiving means set to, for example, several hundred MΩ. As a result, the resistance value of the feedback resistance of the light receiving means for monitoring is set sufficiently low.

  As a result, for the leak resistance of about several hundred GΩ, there is almost no gain fluctuation of the light receiving means for monitoring (sufficiently small), and the gain fluctuation of each light receiving means can be reduced to about 0.1% or less. Therefore, it is possible to detect a change in the irradiation light intensity for correction from the correction illumination unit due to the aging or the like without being affected by the leak resistance.

  The spectral intensity measuring device according to another aspect of the present invention is characterized by further comprising a blocking unit that blocks the measured light while the correction illumination unit is turned on.

  According to the above configuration, it is possible to accurately correct the gain fluctuation based only on the correction illumination light from the correction illumination means without being affected by the incident light from the outside.

  Furthermore, the spectral intensity measuring device according to another aspect of the present invention is characterized in that the illumination light from the correction illumination means is direct light from the correction illumination means.

  According to said structure, the illumination light from the correction | amendment illumination means reaches | attains a light-receiving means with direct light. Therefore, when the wavelength separation means or the short wavelength cut filter is provided, the illumination light directly reaches the light receiving means without passing through the short wavelength cut filter. It is possible to illuminate uniformly and accurately calibrate without lowering.

Further, according to one aspect of the present invention, there is provided a spectral intensity measuring apparatus that separates measured light into a plurality of wavelength components and obtains the spectral intensity of each wavelength component, wherein the measured light is separated into the wavelength components. In a method for calibrating a spectral intensity measuring device including a plurality of light receiving means for receiving measurement light and a correction illumination means for illuminating at the time of calibration, the correction illumination means is turned on, and each of the illuminated light receiving means The correction coefficient is calibrated so that the result of calculating the output level with the correction coefficient set for each light receiving means matches the reference value stored in advance, and the output level from each light receiving means is calibrated during measurement. And calculating the spectral intensity of each wavelength component.

  According to the above configuration, when calibrating a spectral intensity measuring apparatus that separates measured light into a plurality of wavelength components and obtains the spectral intensity of each wavelength component, the spectral intensity measuring apparatus converts the measured light into The wavelength separation means separates each wavelength component and measures even low luminance. For example, a weak photocurrent is a high gain amplifier as the output from the light receiving means comprising a photodiode and a current-voltage conversion circuit. Will be amplified. Therefore, the leakage resistance due to humidity is formed and influenced by the high gain for obtaining the desired sensitivity, particularly the feedback resistance. The resistance value of the leak resistance varies depending on the humidity.

For this reason, in the above invention, in order to correct the output level from each light receiving means, a correction coefficient is set for each light receiving means, and in the calculation control means, the output level from each light receiving means is set to, for example, the correction coefficient. To correct the humidity. And in order to set the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, and each of the obtained result of output level from the light receiving means and calculating a correction coefficient set in each light receiving means, by calibrating the correction coefficient to match the reference value stored in advance, the leakage resistance at that time Correct the gain shift caused by. Then, when the actual measurement, and calculates its calibrated correction factor and output level from the light receiving means, obtaining the spectral intensity of each wavelength component.

  Therefore, the correction of the humidity drift of the spectral intensity measuring device can be realized simply and at low cost by providing the correction illumination means and partially changing the measurement sequence. In this way, gain change due to humidity can be corrected, and accuracy can be maintained under a wide range of environmental conditions. This is particularly effective for portable devices that are required to be used outdoors.

  In the above invention, the incident light to the sensor array which is the forefront of the processing system is used as an input signal, and the gain is corrected based on the digital signal output that has been subjected to signal processing and analog / digital conversion. Gain fluctuations due to all elements of the processing system between output signals can be corrected in a lump. Even if the variable element is an amplification system following the current-voltage converter circuit, it is the reference voltage for analog / digital conversion. However, even if the fluctuation factor is not humidity but temperature or time-lapse, it can also be corrected effectively.

Furthermore, in the spectral reflection characteristic measuring apparatus according to another aspect of the present invention, a plurality of reflected lights of the sample to be measured illuminated by the illumination light from the illumination means and reference light that is the illumination light itself are each provided by the wavelength separation means. The light components are respectively received by a plurality of light receiving means provided for each of the reflected light and the reference light, and the arithmetic control means obtains the relative ratio of the light receiving levels of the corresponding wavelength components, In the spectral reflection characteristic measuring apparatus configured to obtain the spectral reflection characteristic of the sample to be measured, the spectral reflection characteristic measuring apparatus includes correction illumination means for illuminating each of the reflected light and reference light receiving means during calibration, and the calculation control means includes: wherein at the time of calibration, and lighting the correction illumination means, a result of the relative ratio of the output level from the light receiving means are illuminated computed and the correction coefficient set in each light receiving means is prestored Calibrating the correction coefficient to match the reference value, at the time of measurement, it calculates a correction coefficient which is calibrated relative ratio of the output level from the light receiving means, and characterized by determining the relative ratio of the respective wavelength components To do.

  According to the above configuration, the sample to be measured is illuminated with illumination light from the illuminating means in an integrating sphere, etc., and the reflected light is separated into a plurality of wavelength components by the wavelength separating means, and each wavelength component is separated. In the same manner, the reference light, which is the illumination light itself, is also separated into a plurality of wavelength components by the wavelength separating means and received by the light receiving means for each wavelength component, respectively, and the arithmetic control means In calibrating a spectral reflection characteristic measuring device called a spectrocolorimeter, which calculates the spectral reflection characteristic of the sample to be measured by determining the relative ratio of the light receiving levels of the respective wavelength components corresponding to each other. The spectral reflection characteristic measuring apparatus separates the light to be measured and the reference light into a plurality of wavelength components by the wavelength separating means, so that, for example, from the light receiving means comprising a photodiode and a current-voltage conversion circuit. The output will be weak photocurrent is amplified by the amplifier high gain. Therefore, the leakage resistance due to humidity is formed and influenced by the high gain for obtaining the desired sensitivity, particularly the feedback resistance. The resistance value of the leak resistance varies depending on the humidity.

For this reason, in the above invention, in order to correct the relative ratio of the output of each wavelength component, the correction coefficient of the relative ratio of each wavelength component is set, and the arithmetic control means obtains the relative ratio and, for example, corrects it. The humidity is corrected by multiplying by a coefficient. And in order to set the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, and each of the obtained results the relative ratio of the wavelength component calculated with correction coefficients set in respective wavelength components, by calibrating the correction coefficient to match the reference value stored in advance, by the leak resistance at the time Correct the gain deviation. Then, when the actual measurement, and calculates its calibrated correction coefficient and the relative ratio of each wavelength component, determine the spectral reflection characteristics of the sample to be measured.

  Therefore, the correction of the humidity drift of the spectral reflection characteristic measuring apparatus can be realized simply and at low cost by providing the correction illumination means and changing a part of the measurement sequence. In this way, gain change due to humidity can be corrected, and accuracy can be maintained under a wide range of environmental conditions. This is particularly effective for portable devices that are required to be used outdoors.

  In the above invention, the incident light to the sensor array which is the forefront of the processing system is used as an input signal, and the gain is corrected based on the digital signal output that has been subjected to signal processing and analog / digital conversion. Gain fluctuation caused by all the elements of the processing system between output signals can be corrected in a lump, and even if the fluctuation element is an amplification system following the current-voltage converter circuit, the reference voltage of the analog / digital converter Even if the variation factor is not the humidity but the temperature and the time, it can be corrected effectively.

  Furthermore, in the spectral reflection characteristic measuring apparatus which is a ratio measurement and does not require the light receiving means for monitoring in the spectral intensity measuring apparatus, a gain change due to any part replacement of the processing system is corrected, so that production and repair are possible. This reduces the recalibration associated with the replacement of parts at, thereby further reducing costs. In other words, there is no need for recalibration even if parts are replaced, so that most repairs can be made at various repair bases that do not have equipment for gain calibration, and the time required for repair can be shortened. .

  In the spectral reflection characteristic measuring apparatus according to another aspect of the present invention, the illumination light from the correction illumination unit is direct light from the correction illumination unit.

  According to said structure, the illumination light from the correction | amendment illumination means reaches | attains a light-receiving means with direct light. Therefore, when the wavelength separation means or the short wavelength cut filter is provided, the illumination light directly reaches the light receiving means without passing through the short wavelength cut filter. It is possible to illuminate uniformly and accurately calibrate without lowering.

Furthermore, in another aspect of the present invention, the reflected light of the sample to be measured illuminated by the illumination light from the illumination means and the reference light that is the illumination light itself are separated into a plurality of wavelength components and received. A spectral reflection characteristic measuring apparatus for obtaining a spectral reflection characteristic of the sample to be measured by obtaining a relative ratio of light receiving levels of each wavelength component corresponding to each other, wherein each wavelength component of the reflected light and the reference light In the method for calibrating a spectral reflection characteristic measuring apparatus provided with a correction illumination means for illuminating a plurality of light receiving means that respectively receive light to be measured separated at the time of calibration, the correction illumination means is turned on, The result of calculating the relative ratio of the received light levels of the corresponding wavelength components from the respective light receiving means for the reflected reflected light and the reference light with the correction coefficient set for each wavelength component is recorded in advance. The correction coefficient is calibrated so as to coincide with the reference value that is set, and at the time of measurement, the relative ratio of the output of each wavelength component is calculated with the calibrated correction coefficient, and the spectral reflection characteristic of the sample to be measured is obtained. It is characterized by.

According to the above configuration, the reflected light of the sample to be measured illuminated by the illumination light from the illumination means and the reference light that is the illumination light itself are separated into a plurality of wavelength components, respectively, and the wavelengths corresponding to each other are separated. In calibrating the spectral reflection characteristic measuring apparatus that calculates the spectral reflection characteristic of the sample to be measured by calculating the relative ratio of the light reception levels of the components, the spectral reflection characteristic measuring apparatus uses the reflected light and the illumination light as wavelengths. The light is separated into a plurality of wavelength components by the separating means and measured to a low luminance. For example, a weak photocurrent is output by a high gain amplifier as an output from the light receiving means comprising a photodiode and a current-voltage conversion circuit. It will be amplified. Therefore, to achieve the high gain in order to obtain the sensitivity of the desired, in particular with respect to the feedback resistor, the leak resistance due to humidity is formed, will be affected in its. The resistance value of the leak resistance varies depending on the humidity.

For this reason, in the above invention, in order to correct the relative ratio of the output of each wavelength component, the correction coefficient of the relative ratio of each wavelength component is set, and the arithmetic control means obtains the relative ratio and, for example, corrects it. The humidity is corrected by multiplying by a coefficient. Then, in order to calibrate the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, and each of the obtained results the relative ratio of the wavelength component calculated with correction coefficients set in respective wavelength components, by calibrating the correction coefficient to match the reference value stored in advance, by the leak resistance at the time Correct the gain deviation. Then, when the actual measurement, and calculates its calibrated correction coefficient and the relative ratio of each wavelength component, determine the spectral reflection characteristics of the sample to be measured.

  Therefore, the correction of the humidity drift of the spectral reflection characteristic measuring apparatus can be realized simply and at low cost by providing the correction illumination means and changing a part of the measurement sequence. In this way, gain change due to humidity can be corrected, and accuracy can be maintained under a wide range of environmental conditions. This is particularly effective for portable devices that are required to be used outdoors.

  In the above invention, the incident light to the sensor array which is the forefront of the processing system is used as an input signal, and the gain is corrected based on the digital signal output that has been subjected to signal processing and analog / digital conversion. Gain fluctuation caused by all the elements of the processing system between output signals can be corrected in a lump, and even if the fluctuation element is an amplification system following the current-voltage converter circuit, the reference voltage of the analog / digital converter Even if the variation factor is not the humidity but the temperature and the time, it can be corrected effectively.

  Furthermore, in the spectral reflection characteristic measuring apparatus which is a ratio measurement and does not require the light receiving means for monitoring in the spectral intensity measuring apparatus, a gain change due to any part replacement of the processing system is corrected, so that production and repair are possible. This reduces the recalibration associated with the replacement of parts at, thereby further reducing costs. In other words, there is no need for recalibration even if parts are replaced, so that most repairs can be made at various repair bases that do not have equipment for gain calibration, and the time required for repair can be shortened. .

As described above, the spectral intensity measuring device according to each aspect of the present invention is a spectral luminance meter in which the light to be measured is separated into a plurality of wavelength components and the spectral intensity of each wavelength component is obtained by a plurality of light receiving means. When calibrating a spectral intensity measuring device referred to as above, in the spectral intensity measuring device, a weak photocurrent is amplified by a high gain amplifier in the light receiving means, and the high gain for obtaining a desired sensitivity is obtained. In particular, with respect to the feedback resistance, a leakage resistance due to humidity is formed and is affected by this. Therefore, a correction coefficient is set for each light receiving means, and the output level from each light receiving means is corrected, for example, The humidity is corrected by multiplying by a coefficient. Furthermore, in order to set the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, result of output level from the light receiving means and calculating a correction coefficient set in each light receiving means, by calibrating the correction coefficient to match the reference value stored in advance, the leakage resistance at that time Correct the gain shift caused by. Then, when the actual measurement, and calculates its calibrated correction factor and output level from the light receiving means, obtaining the spectral intensity of each wavelength component.

  Therefore, correction of the humidity drift of the spectral intensity measuring device can be realized simply and at low cost by providing the correction illumination means and changing part of the measurement sequence.

Furthermore, as described above, the spectral reflection characteristic measuring apparatus of each aspect of the present invention illuminates the sample to be measured with illumination light from the illuminating means in an integrating sphere or the like, and reflects the reflected light with a plurality of wavelength components. The reference light, which is the illumination light itself, is similarly separated into a plurality of wavelength components and received by the light receiving means for each wavelength component. Then, a spectral reflection characteristic measuring device called a spectrocolorimeter that calibrates the spectral reflection characteristic of the sample to be measured by determining the relative ratio of the light receiving levels of the corresponding wavelength components is calibrated. In this spectral reflection characteristic measuring apparatus, a weak photocurrent is amplified by a high gain amplifier in the light receiving means, and the high gain for obtaining a desired sensitivity is realized, particularly a feedback resistor. , A leakage resistance due to humidity is formed and is affected by it, so that a correction coefficient is set for the relative ratio of each wavelength component, and the relative ratio is multiplied by the correction coefficient, for example, Make corrections for humidity. Furthermore, in order to set the correction coefficient corresponding to the resistance value of the leak resistance that changes in a relatively short time, a correction illumination means is provided, which is lit during the calibration, results the relative ratio of the wavelength component calculated with correction coefficients set in respective wavelength components, by calibrating the correction coefficient to match the reference value stored in advance, by the leak resistance at the time Correct the gain deviation. Then, when the actual measurement, and calculates its calibrated correction coefficient and the relative ratio of each wavelength component, determine the spectral reflection characteristics of the sample to be measured.

  Therefore, correction of the humidity drift of the spectral reflection characteristic measuring apparatus can be realized simply and at low cost by providing the correction illumination means and partially changing the measurement sequence.

[Embodiment 1]
FIG. 1 is a cross-sectional view schematically showing a configuration of a spectral luminance meter 31 that is a spectral intensity measuring apparatus according to an embodiment of the present invention. The spectral luminance meter 31 generally includes a polychromator 32, a light receiving optical system 33, a shutter device 34, a processing circuit 35, and an arithmetic control circuit 36.

  The light to be measured converges on the entrance aperture SL of the polychromator 32 via the light receiving optical system 33. In front of the entrance aperture SL, a shutter device 34 controlled by the arithmetic control circuit 36 is provided to control the incidence of the light to be measured. Specifically, it is shielded at the time of non-measurement and at the time of calibration described later, and is opened at the time of photometry.

  The light to be measured that has entered from the entrance aperture SL is converted into a parallel light flux by the imaging optical system 39 and is incident on the diffraction grating 40, and is dispersedly reflected in different directions for each wavelength, and again through the imaging optical system 39. A dispersion image of the incident aperture SL is formed on the light receiving sensor array SA provided on the wall surface where the incident aperture SL is formed.

  As shown in FIG. 2, the light receiving sensor array SA includes the silicon photodiode array in which n (for example, n = 32) pixel sensors S1, S2,..., Sn are arranged at equal intervals. In S2 to Sn, for example, a dispersion image of the incident aperture SL is formed by monochromatic light of 400 to 700 nm. The outputs of the pixel sensors S1 to Sn of the light receiving sensor array SA are sent to the arithmetic control circuit 36 through the processing of the processing circuit 35 comprising the processing circuit 11 shown in FIG. The light receiving sensor array SA and the processing circuit 35 constitute light receiving means. The arithmetic control circuit 36 which is an arithmetic control means calculates | requires and outputs the spectral intensity of the to-be-measured light from the output signals s1-sn of each light-receiving means as mentioned later.

  It should be noted that the polychromator 32 is provided with a gain correction LED 42 as an illumination means. The gain correction LED 42 is controlled to be turned on by the arithmetic control circuit 36. Specifically, the gain correction LED 42 is turned on during calibration, which will be described later, and is turned off during non-measurement and measurement. Further, the arithmetic control circuit 36 corrects the humidity drift of the operational amplifier A by the feedback resistor Rf 'shown in FIG. 8, as will be described later, from the output signals s11 to s1n of the respective light receiving means at the time of lighting.

  In the spectral luminance meter 31 configured as described above, the calibration operation for the humidity drift will be described below. The arithmetic control circuit 36 opens the shutter, and sequentially receives the output signals s21 to s2n of each light receiving means for the light to be measured by the multiplexer 12 and stores them. Immediately thereafter, the shutter is closed to cause the correction LED 42 to emit light, and the output signals s11 to s1n of the respective light receiving means illuminated with the output light are sequentially captured and stored in the same manner.

  The correction LED 42 is arranged to illuminate all the pixel sensors S1 to Sn of the light receiving sensor array SA substantially uniformly. Further, since the output light of the correction LED 42 is directly irradiated to the light receiving sensor array SA without passing through the diffraction grating 40, the output signals s11 to s1n of the respective light receiving means are the imaging optical system 39 and the diffraction grating 40. It is not affected by the spectral characteristics of the spectroscopic optical system and the change thereof and the wavelength change of the output light.

  On the other hand, as the output level of the correction LED 42 changes, the illuminance level changes, but the relative illuminance distribution does not change. Therefore, when the spectral luminance meter 31 is calibrated at the manufacturing factory, the arithmetic control circuit 36 closes the shutter and causes the correction LED 42 to emit light, and outputs the output signals s01 to s0n of the respective light receiving means of the light receiving sensor array SA to the initial values. Remember as.

If the illuminance level of the correction LED 42 does not change, the gain correction coefficient Ci of an arbitrary pixel sensor Si (i is a natural number from 1 to n) can be obtained by Ci = s0i / s1i, but is corrected as described above. The illuminance level may change due to a change in the emission intensity of the LED 42 for this purpose. For this reason, the pixel sensor S1 with i = 1 is used as the reference pixel (monitoring light receiving means), and its relative correction coefficient C1 = s01 / s11. Correct by ratio. That is, if the corrected gain correction coefficient of an arbitrary pixel is Ci ′,
Ci ′ = Ci / C1 = (s0i / s1i) * (s01 / s11)
It becomes. As a result, the output signal s2i for the light to be measured is corrected by the following equation using the gain correction coefficient Ci ′.

s2i ′ = s2i * Ci ′ = s2i * (s0i / s1i) * (s01 / s11)
By the way, in the above description, the pixel of i = 1 is selected as the reference pixel, but the change of the gain of this pixel due to the humidity must be sufficiently small. Therefore, referring to the processing circuit 11 shown in FIG. 7, the feedback resistor Rf1 of the current-voltage conversion circuit A1 corresponding to the reference pixel is formed to be small enough not to be affected by the leakage resistor Rf ′ shown in FIG. Has been. For example, the feedback resistors Rf2, Rf3,... Corresponding to the pixel sensors S2, S3,... That receive the short wavelength side where the sensitivity (current-voltage conversion characteristic) of the photodiode is low is about several hundred MΩ. On the other hand, it is 1 MΩ or less, for example, about several hundreds kΩ in this embodiment.

  On the other hand, when the resistance value of the feedback resistor Rf1 is reduced in this way, the gain of the current-voltage conversion circuit A1 is significantly lower than the gains of the current-voltage conversion circuits A2 to An of other channels. This can be compensated by making the gain of the variable gain amplifier 13 at the subsequent stage larger than that of the other channels. Even with the same gain in total, the gain of the current-voltage conversion circuit A1 is low, so the S / N of this reference pixel is significantly lower than other pixels, so the output signal s1 of this pixel is used only for gain correction and is used for measurement. Is not used.

In addition to the method for reducing the feedback resistance Rf, there are the following methods as a method for suppressing the change in the gain of the reference pixel due to humidity to a sufficiently small level that does not cause a problem. Any combination of the methods may be used.
1. The input terminal of the operational amplifier of the reference pixel is floated in the air without being connected to the pattern on the substrate, and the signal line from the pixel sensor S1 and the feedback resistor Rf1 are so-called air-wired. In this case, since the input terminal is insulated by air, the influence of humidity can be ignored.
2. The input terminal of the operational amplifier of the reference pixel and the feedback resistor Rf1 are potted with a resin such as epoxy that hardly transmits moisture. However, this resin coat is easy and low-cost, unlike the moisture-proof coat by vapor deposition described in the above-mentioned prior art.
3. In addition to the light receiving sensor array SA, a reference sensor having a larger light receiving area than the pixel sensors S2 to Sn of the light receiving sensor array SA is disposed in the vicinity. The reference sensor has a sufficiently large output current as compared with the light receiving sensor array SA, and the feedback resistance Rf can be made small enough not to be affected by the leakage resistance Rf ′.

  In this way, when correcting the spectral luminance meter 31 that separates the light to be measured into a plurality of wavelength components and obtains the spectral intensity of each wavelength component, a correction LED 42 is provided, and a part of the measurement sequence is provided. Humidity drift correction can be realized simply and at low cost simply by changing. Thus, accuracy can be maintained over a wide range of environmental conditions. This is particularly effective for portable devices that are required to be used outdoors.

  Further, in the spectral luminance meter 31, the incident light to the light receiving sensor array SA which is the forefront part of the processing system is used as an input signal, based on the digital signal output subjected to signal processing and analog / digital conversion by the processing circuit 35. Since the calculation control circuit 36 corrects the gain, it is possible to collectively correct the gain fluctuation caused by all the elements of the processing system between the input and output signals, and the fluctuation elements are the current-voltage conversion circuits A1 to An. Even if it is an amplification system such as a gain variable amplifier 13 that follows the reference voltage of the analog / digital converter 14, the monitor described later is used regardless of whether the variation factor is not humidity but temperature or time-lapse. As long as there is no change in the gains of the light receiving means for use and the processing system at the subsequent stage, the correction can be made effectively together.

  Further, in the light receiving sensor array SA, the pixel sensor S1 is provided for monitoring the illumination light from the correction LED 42 adjacent to the measurement pixel sensors S2 to Sn. Change of the illumination light intensity for correction, and the corresponding current-voltage conversion circuit A1 is formed with a sufficiently small gain fluctuation compared to the other current-voltage conversion circuits A2 to An, and the correction LED 42 is turned on. The correction outputs s12 to s1n obtained in this way are relativized by the output s11 of the current / voltage conversion circuit A1 for monitoring, so that the change is canceled out. Therefore, the correction coefficients C2 ′ to Cn ′ used for correcting the humidity drift Can be more accurately calibrated. Further, even if the fluctuation factor is the replacement of parts of the processing system in the repair or production process, the pixel sensor S1 and the current-voltage conversion circuit A1, which are the light receiving means for monitoring, and the processing system in the subsequent stage are obtained because of the relativeization. As long as there is no change in the gain, it can be automatically corrected.

  Furthermore, the resistance value of the feedback resistor Rf1 of the monitoring current / voltage conversion circuit A1 is compared with the resistance value of the feedback resistors Rf2, Rf3,... Of the remaining high gain current / voltage conversion circuits A2, A3,. By making it sufficiently small, there is almost no gain variation of the light receiving means for monitoring with respect to the leakage resistance Rf ′ of about several hundred GΩ (sufficiently small), and it is about 0.1% or less of the gain variation of each light receiving means. It can be. Therefore, a change in the intensity of irradiation light for correction from the correction LED 42 due to the aging or the like can be detected more accurately without being affected by the leak resistance.

  Further, the correction coefficients C2 ′ to Cn ′ are derived for each of the pixel sensors S2 to Sn, which are light receiving means for measurement, and the corresponding current-voltage conversion circuits A2 to An, and gain fluctuations due to the leak resistance Rf ′ are derived. Since the correction is performed, the spectral intensity can be obtained by accurately correcting the influence of the gain fluctuation due to the humidity.

  Furthermore, immediately after obtaining the output signals s21 to s2n of each light receiving means (or immediately before), the correction LED 42 is turned on to obtain correction coefficients C2 ′ to Cn ′, and the corrected output signals s22 ′ to s2n ′. Therefore, even if the gain fluctuation due to humidity is rapid, the influence can be eliminated.

  In the above description, although the LED 42 has been described as the light source for correction, other light sources may be used, and the entire elongated light receiving sensor array SA can be uniformly irradiated with light, and the heat generation is small and the change with time is not caused. Less is preferred. For example, organic EL etc. can be used. The LED 42 requires almost no replacement of the correction light source due to its life.

  The correction LED 42 preferably has a wavelength with which the pixel sensors S1 to Sn have sufficient sensitivity, for example, a long wavelength region from red to near infrared. Furthermore, in FIG. 1, as indicated by reference numeral 43, in order to remove the influence of the secondary light by the diffraction grating 40, a short wavelength cut filter is disposed close to a part of the light receiving sensor array SA. The wavelength of the correction LED 42 is preferably a wavelength that passes through the short wavelength cut filter, and from this point, the red to the near infrared are desirable. Although many LEDs have a package with a lens, thermal deformation of the LED can cause a change in light distribution. Therefore, it is desirable to suppress the drive current and drive time of the correction LED 42 as much as possible. A diffusion plate may be disposed in the vicinity of the correction LED 42 so that the light distribution change of the correction LED 42 does not directly cause the illuminance distribution on the light receiving sensor array SA. The correction LED 42 directly illuminates the sensor array SA. However, the correction LED 42 may illuminate the housing of the spectroscopic means and scatter and reflect the light inside the light receiving sensor array SA. Furthermore, a plurality of correction LEDs 42 may be provided.

[Embodiment 2]
FIG. 3 is a cross-sectional view schematically showing a configuration of a spectrocolorimeter 51 which is a spectral reflection characteristic measuring apparatus according to another embodiment of the present invention, and FIG. 4 shows the vicinity of the polychromator 32a in the spectrocolorimeter 51. FIG. The spectrocolorimeter 51 is similar to the spectral luminance meter 31 described above, and corresponding portions are denoted by the same reference numerals, and description thereof is omitted. The spectrocolorimeter 51 generally includes a polychromator 32a, the light receiving optical system 33, a processing circuit 35a, and an arithmetic control circuit 36a, a xenon flash light source 52, an integrating sphere 53, and the xenon. An optical fiber 54 that guides illumination light from the flash light source 52 and the integrating sphere 53 directly to the polychromator 32a is provided.

  Since the spectrocolorimeter 51 measures the spectral characteristics of the sample 55 to be measured placed on the placing table 53 a, the diffuse illumination light produced by the multiple reflection of the irradiation light from the xenon flash light source 52 by the integrating sphere 53. The spectral characteristic is measured from the ratio of the measurement results of the respective received light levels of the reflected light from the sample 55 illuminated in step 1 and the reference light that is the irradiation light itself. As shown in FIG. 4, the polychromator 32a is a dual beam system that separates these two incident lights independently. Therefore, although it has basically the same configuration as the polychromator 32 described above, when the incident aperture side is viewed from the diffraction grating 40, as shown in FIG. 5, the incident aperture SL1 for the sample light and the reference light is used. , SL2 and the light receiving sensor arrays SA1 and SA2 for sample light and reference light corresponding to them are different.

  The illuminating means for illuminating the sample 55 to be measured includes the integrating sphere 53 and a xenon flash light source 52 which is inside and driven by the arithmetic control circuit 36a. The integrating sphere 53 is coated with white paint, and when the arithmetic and control circuit 36a causes the xenon flash light source 52 to emit light, the light beam is reflected in the integrating sphere 53 to diffusely illuminate the sample. A component (hereinafter, sample light) in a specific direction of reflected light from the sample (in the figure, the normal direction of the sample surface) is incident on the sample light incident aperture SL1 of the polychromator 32a by the light receiving optical system 33. At the same time, part of the illumination light enters the reference optical fiber 54 having an incident end in the integrating sphere 53 and is guided to the reference light entrance aperture SL2 of the polychromator 32a.

  Similar to the polychromator 32, the incident sample light and the reference light are incident on the light incident sensor arrays SA1 and SA2 for the sample light and the reference light by the imaging optical system 39 and the diffraction grating 40, respectively. , SL2 is created. Output signals s1 to sn and r1 to rn of the pixel sensors S1 to Sn and R1 to Rn of the light receiving sensor arrays SA1 and SA2 are arithmetically controlled through a processing circuit 35a having two systems of the processing circuit 11 of FIG. It is sent to the circuit 36a. The arithmetic and control circuit 36 processes the output signals s1 to sn and r1 to rn from the pixel sensors S1 to Sn and R1 to Rn of the light receiving sensor arrays SA1 and SA2 for the sample light and the reference light, and spectroscopically measures the sample to be measured. Obtain the reflection characteristics and output. In the light receiving sensor arrays SA1 and SA2, a gain correction LED 42 controlled by the arithmetic control circuit 36a illuminates all pixels substantially uniformly.

  In the spectrocolorimeter 51 configured as described above, a general spectral reflection characteristic calculation operation will be described below. First, prior to the measurement of the sample 55 to be measured, a white sample for calibration whose spectral reflectance coefficient W (λ) is known is placed on the mounting table 53a, the xenon flash light source 52 is caused to emit light, and its spectral reflection is measured. Characteristics are measured. The arithmetic control circuit 36a outputs the output signal s0i of each pixel sensor Si (i = 1 to n) of the sample light receiving sensor array SA1 and the output signal r0i of each pixel sensor Ri of the reference light receiving sensor array SA2. Ratio D0i = s0i / r0i is obtained and stored together with the spectral reflectance coefficient W (λ).

  Next, the sample 55 to be measured is placed on the mounting table 53a, and the same measurement is performed. The output signal s2i of the pixel sensor Si of each sample light receiving sensor array SA1 and the reference light receiving sensor array. A ratio D2i = s2i / r2i with the output signal r2i of each pixel sensor Ri of SA2 is obtained and stored. Further, Ei = D2i / D0i is obtained, and this is interpolated based on the separately obtained correspondence table of the pixel number i and the wavelength λi, and E (λ) corresponding to the wavelength λ is obtained. Thereby, the reflection characteristic F (λ) of the sample can be obtained by the following equation.

F (λ) = W (λ) * E (λ)
Next, the calculation operation of the spectral reflection characteristic with the humidity drift calibrated according to the present invention will be described. As described above, the spectrocolorimeter 51 that measures the reflection characteristics reflects the reflection characteristics from the output ratios D0i and D2i of the two light receiving sensor arrays SA1 and SA2 for the sample light and the reference light for the white calibration sample and the sample to be measured. Therefore, if the gain ratio G2i with respect to the output signals si and ri from the corresponding two pixel sensors Si and Ri of the sample light and reference light receiving sensor arrays SA1 and SA2 does not change, the reflection characteristic measurement value has an effect. Not receive. Further, since white calibration performed by the user is a reference, the gain ratio G2i is corrected to be equal to the ratio G0i at the time of white calibration.

  However, if the gain ratio G2i at the time of measurement deviates from the gain ratio G0i at the time of white calibration due to the humidity drift, the reflection characteristic measurement value is affected. In particular, in the configuration using the two beams for the sample light and the reference light, errors generated in the respective light receiving sensor arrays SA1 and SA2 act synergistically to generate a large error. Here, if white calibration is frequently performed, the influence of the humidity drift on the reflection characteristic measurement value can be reduced. However, normally, white calibration is performed only once before the measurement work for one day, and such frequent calibration is not practical.

  Therefore, in the present invention, it is noted that the gain ratios G0i and G2i can be monitored by the output ratios D10i and D12i of the output signals si and ri from the corresponding two pixel sensors Si and Ri illuminated at a constant illuminance ratio. Then, the spectral reflection characteristic calculation operation including correction of humidity drift is performed as follows. That is, the illumination light from the correction LED 42 does not change the relative illuminance between the pixels even if the illuminance level changes, so that the gain ratio of the corresponding two pixels can be monitored by the output ratios D10i and D12i at that time.

  First, at the time of the white calibration, the calibration white sample is placed on the mounting table 53a, the xenon flash light source 52 is caused to emit light, and the output of the pixel sensor Si of each sample light receiving sensor array SA1 as described above. A ratio D0i = s0i / r0i between the signal s0i and the output signal r0i of each pixel sensor Ri of the reference light receiving sensor array SA2 is obtained and stored together with the known spectral reflectance coefficient W (λ). In the present invention, immediately after this, the xenon flash light source 52 is turned off, the correction LED 42 is turned on, the same measurement is performed, and the output ratio D10i = s10i / r10i is obtained and stored.

  Next, the xenon flash light source 52 is caused to emit light to the sample 55 to be measured, and the output ratio D2i is obtained in the same manner as described above. In the present embodiment, immediately after this, the correction LED 42 is turned on, the same measurement is performed, and the output ratio D12i = s12i / r12i is obtained and stored.

  From the output ratios D10i and D12i thus determined, the arithmetic control circuit 36a calibrates the gain ratio D2i determined for the sample to be measured as follows.

D2i ′ = D2i (D10i / D12i)
Then, from the gain ratio D2i ′, the spectral reflection characteristic is obtained by the above-described procedure.

  In this calibration method, the change in the illuminance distribution of the illumination light on the sensor arrays SA1 and SA2 by the correction LED 42 becomes a correction error. However, the orientation of the LED 42 that affects the illuminance distribution and the reflection characteristics inside the housing are at least 1. Since there is no change during the white calibration performed once a day, the calibration error is smaller than that of the spectral luminance meter 31. The amount of light and wavelength are highly temperature dependent and change in a short time, but do not affect the illuminance distribution.

  In this way, the calibration of the spectrocolorimeter 51 that determines the spectral reflection characteristics of the sample to be measured from the reflected light of the sample to be measured illuminated by the illumination light and the reference light that is the illumination light itself is performed. The humidity drift correction can be realized easily and at low cost by providing the correction LED 42 and changing only part of the measurement sequence.

  Further, in the spectrocolorimeter 51, incident light to the light receiving sensor arrays SA1 and SA2, which are the forefront of the processing system, is used as an input signal, and a digital signal output subjected to signal processing and analog / digital conversion by the processing circuit 35a. Since the gain is corrected by the arithmetic control circuit 36a based on this, it is possible to collectively correct the gain fluctuation caused by all the elements of the processing system between the input and output signals, and the fluctuation element is the current-voltage conversion circuit. Even if it is an amplification system such as a gain variable amplifier 13 following A1 to An, or the reference voltage of the analog / digital converter 14, even if the fluctuation factor is not humidity but temperature or time-dependent, It can also be corrected effectively.

  Furthermore, in the spectrocolorimeter 51 that performs measurement from the relative ratio of the output signals si and ri of the pixel sensors Si and Ri of the sensor arrays SA1 and SA2, a reference pixel such as the above-described spectral luminance meter 31 is unnecessary. Therefore, since a gain change due to any part replacement of the processing system is corrected, recalibration accompanying part replacement in production or repair can be reduced, and further cost reduction can be achieved. In other words, there is no need for recalibration even if parts are replaced, so that most repairs can be made at various repair bases that do not have equipment for gain calibration, and the time required for repair can be shortened. .

It is sectional drawing which shows typically the structure of the spectral luminance meter which is the spectral intensity measuring apparatus of one Embodiment of this invention. It is a front view explaining the light reception sensor array in the spectral luminance meter shown in FIG. It is sectional drawing which shows typically the structure of the spectral colorimeter which is the spectral reflection characteristic measuring apparatus of the other form of implementation of this invention. FIG. 4 is a perspective view of the vicinity of a polychromator in the spectrocolorimeter shown in FIG. 3. FIG. 4 is a front view for explaining a light receiving sensor array in the spectrocolorimeter shown in FIG. 3. It is sectional drawing which shows schematic structure of a general polychromator. It is a block diagram which shows one structural example of the processing circuit corresponding to the silicon photodiode array in the said polychromator. It is a block diagram which shows the example of a general current-voltage conversion circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Processing circuit 12 Multiplexer 13 Variable gain amplifier 14 Analog / digital converter 21 Current-voltage conversion circuit 31 Spectral luminance meter 32, 32a Polychromator 33 Light-receiving optical system 34 Shutter device 35, 35a Processing circuit 36, 36a Operation control circuit 39 Imaging Optical system 40 Diffraction grating 42 Gain correction LED
51 Spectral Colorimeter 52 Xenon Flash Light Source 53 Integrating Sphere 54 Optical Fiber A Operational Amplifiers A1 to An Current Voltage Conversion Circuit Ri Leakage Resistance RF1 to RFn Feedback Resistance Rf Feedback Resistance Rf ′ Leakage Resistance R1 to Rn Pixel Sensors S1 to Sn Pixel Sensor SA ; SA1, SA2 light receiving sensor array SL; SL1, SL2 entrance aperture

Claims (9)

In the spectral intensity measuring device in which the light to be measured is separated into a plurality of wavelength components by the wavelength separating means, and received by each of the plurality of light receiving means, and the spectral intensity of each wavelength component is obtained.
Correction illumination means for illuminating each light receiving means during calibration;
At the time of the calibration, the correction illumination means is turned on, and the result obtained by calculating the output level from each illuminated light receiving means and the correction coefficient set in each light receiving means matches the reference value stored in advance. And a calculation control means for calculating the output level from each light receiving means and the corrected correction coefficient to obtain the spectral intensity of each wavelength component at the time of measurement. measuring device. Adjacent to the light receiving means, for monitoring the illumination light from the correction lighting means, further comprising a monitoring light receiving means having a smaller gain variation than the light receiving means,
2. The spectral intensity measuring apparatus according to claim 1, wherein the arithmetic control means relativizes correction outputs obtained from the plurality of light receiving means by outputs of the monitor light receiving means.   3. The spectral intensity according to claim 2, wherein the gain of the amplifier at the subsequent stage of the light receiving means for monitoring is increased and the resistance value of the feedback resistor of the current-voltage conversion circuit in the light receiving means for monitoring is 1 MΩ or less. measuring device.   The spectral intensity measuring device according to any one of claims 1 to 3, further comprising a blocking unit that blocks the light to be measured while the correction illumination unit is turned on.   The spectral intensity measurement apparatus according to any one of claims 1 to 4, wherein the illumination light from the correction illumination unit is direct light from the correction illumination unit. A spectral intensity measuring device that separates measured light into a plurality of wavelength components and obtains the spectral intensity of each wavelength component, and receives a plurality of measured lights separated into the respective wavelength components. In a method for calibrating a spectral intensity measuring device comprising a correction illumination means for illuminating at the time of calibration ,
The correction coefficient is turned on so that the result of calculating the output level from each illuminated light-receiving means and the correction coefficient set in each light-receiving means matches the reference value stored in advance. Calibrate the
At the time of measurement, a calibration method for a spectral intensity measuring device, wherein the output level from each light receiving means is calculated as a calibrated correction coefficient to obtain the spectral intensity of each wavelength component. The reflected light of the sample to be measured illuminated by the illumination light from the illumination means and the reference light that is the illumination light itself are separated into a plurality of wavelength components by the wavelength separation means, and provided for each of the reflected light and the reference light. Spectral reflection characteristic measurement for obtaining the spectral reflection characteristic of the sample to be measured by receiving the light by each of the plurality of light receiving means and obtaining the relative ratio of the received light levels of the corresponding wavelength components by the arithmetic control means. In the device
A correction illumination means for illuminating the light receiving means for reflected light and reference light at the time of calibration,
At the time of the calibration, the calculation control means turns on the correction illumination means, and the calculation result of the relative ratio of the output level from each illuminated light receiving means and the correction coefficient set in each light receiving means is stored in advance. The correction coefficient is calibrated so as to match the reference value, and at the time of measurement, the relative ratio of the output levels from each light receiving means is calculated with the calibrated correction coefficient to obtain the relative ratio of each wavelength component. Spectral reflection characteristic measuring device.   8. The spectral reflection characteristic measuring apparatus according to claim 7, wherein the illumination light from the correction illumination unit is direct light from the correction illumination unit. The reflected light of the sample to be measured illuminated by the illumination light from the illumination means and the reference light, which is the illumination light itself, are separated into a plurality of wavelength components and received, and the light reception levels of the respective wavelength components corresponding to each other are received. A spectral reflection characteristic measuring apparatus for obtaining a spectral reflection characteristic of the sample to be measured by obtaining a relative ratio, and receiving the light to be measured separated into wavelength components of the reflected light and the reference light, respectively. In a method for calibrating a spectral reflection characteristic measuring apparatus including a correction illumination unit that illuminates a plurality of light receiving units during calibration,
The correction illumination unit is turned on, and the relative ratio of the received light levels of the corresponding wavelength components from the illuminated reflected light and reference light receiving units is set to the correction coefficient set for each wavelength component. The correction coefficient is calibrated so that the calculated result matches the reference value stored in advance,
At the time of measurement, a calibration method for a spectral reflection characteristic measuring apparatus, wherein the relative ratio of the output of each wavelength component is calculated as a calibrated correction coefficient to obtain a spectral reflection characteristic of the sample to be measured.

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