JPH03138538A - Method for measuring spectral distribution of light source and method for measuring spectral responsiveness of photodetector system - Google Patents

Abstract

PURPOSE:To make easy measurement by adopting the constitution to measure the photodetector output of every set wavelength via a monochrometer for the light from a sample surface and comparing the respective values of the reflection spectral radiation luminance rate, relative external fluorescent radiation efficiency and relative spectral distribution of the fluorescent component thereof and known data values. CONSTITUTION:The total spectral radiation luminance rate betaw(lambda) of the i-th fluorescent sample is determined from Yw(lambda), Yt,x,i(lambda) when the photodetector output obtd. by installing a normal standard white surface on the sample surface is designated as Yw(lambda), and the photodetector output obtd. by installing the i-th (i=1 to n) fluorescent sample as Yf,x,i(lambda) (i=1 to n), the spectral radiation luminance rate betaw(lambda) of the above-mentioned normal standard white surface and equation I. The effective excitation efficiency ND,I under the light source SD(mu) for photometry of the i-th fluorescent sample is determined from the relative external fluorescent radiation efficiency Qx,i(mu) of the i-th fluorescent sample when the spectral distribution of the light source D for photometry of the known value is designated as SD(lambda) and equation II. Further, the spectral distribution SX(lambda) of the light source X is determined from the reflected spectral radiation luminance rate betao,i(lambda) of the i-th fluorescent sample, the relative spectral distribution Fi, (lambda) of the fluorescent component, the total spectral radiation luminance rate betat,x,i(lambda), and the effective excitation efficiency ND,I and equation III.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a fluorescent object color measuring device, and more specifically,
What color does a sample containing a fluorescent dye or pigment appear under a given illumination light?

In other words, the present invention relates to a method for measuring the spectral distribution of a light source and the spectral responsivity of a light receiver system in a measuring device that supplies numerical values necessary for calculating a fluorescent object color.

(Conventional technology) Samples containing fluorescent dyes or fluorescent pigments (hereinafter referred to as:

The object color of a fluorescent sample (hereinafter referred to as fluorescent object color) differs greatly from that of a non-fluorescent sample due to its spectral radiance coefficient (apparent spectral reflection of the sample with respect to a standard white surface). rate) differs depending on the type of illumination light and receiver system.

In general, it is not possible to calculate the color of an object under arbitrary illumination light only from the spectral radiance factor measured using a single illumination light or a light receiver system.

For this reason, various methods for measuring fluorescent object colors have been proposed in the past.1 A typical method for measuring fluorescent object colors is specified in the Wood Industry Standard JIS Z 8717 (method for measuring fluorescent object colors)6. There are different methods. Further, as a general method for measuring the color of a non-fluorescent object, there is a method specified in the Wood Industry Standard JIS Z 8722 (Method for Measuring Object Color).

Various fluorescent object color measuring devices and object color measuring devices have been manufactured based on the measurement principles of these methods.

It is used.

To find the fluorescent object color under arbitrary illumination light,
Among the six types of measurement methods specified in JIS Z 8717, the one-light source fluorescence separation method or the two-light source fluorescence separation method is suitable. How are these measured?

The illumination condition is that the sample surface is irradiated with light from a light source directly or through an optical system with low wavelength selectivity or through one integrating sphere (hereinafter referred to as white light illumination), and the light from the sample surface is irradiated with light from a light source. Observation conditions (hereinafter referred to as "observation conditions") in which the light is guided through a monochromator to a light receiver and the output of the light receiver is measured for each set wavelength of the monochromator.

It mainly performs measurements in white light illumination and spectroscopic observation (referred to as spectral observation). Furthermore, in sub-measurements.

The illumination condition is that the sample surface is irradiated with light from a light source via a monochromator (hereinafter referred to as neutral color illumination), and the light from the sample surface is irradiated directly or via an optical system with less wavelength selectivity. , observation conditions leading to the receiver via the integrating sphere (hereinafter,
(referred to as non-spectroscopic observation), an object color measuring device with neutral color illumination and non-spectral observation method is required.

One of the differences between the method of measuring fluorescent object color and the method of measuring non-fluorescent object color is that when measuring fluorescent object color under white light illumination and spectroscopic observation, illumination light (hereinafter referred to as The relative spectral distribution of the sample surface illumination light (referred to as sample surface illumination light) must be known, and when measuring fluorescent object color under neutral color illumination and non-spectral observation, the relative spectral responsivity of the receiver system must be known. There are things that must be done.

In contrast, when measuring the color of a non-fluorescent object, even if the relative spectral distribution of the illumination light on the sample surface and the relative spectral response of the photodetector system are unknown, there is no problem in the measurement. On the other hand, since the optical systems of the fluorescent object color measuring device and the object color measuring device have many parts in common,
The conventional fluorescent object color measuring device is a repurposed object color measuring device.

Due to its modified structure, conventional fluorescent object color measurement devices do not take into account the user's ability to measure the spectral distribution of sample surface illumination light or the relative spectral response of the receiver. . For this reason, the above-mentioned JIS Z 8717 annex also assumes how to obtain the relative spectral distribution of the sample surface illumination light.

(Problem to be Solved by the Invention) The appendix shows several methods of determination, but basically the spectral coloring method based on Japanese Industrial Standards FF1JIs Z 8724 (method for measuring light source color) is used. We are hiring. In other words, in order to obtain the relative spectral distribution of the sample surface illumination light, a coloring device such as the 1-minute ray 51 and a standard light bulb as a standard for comparison of the spectral distribution are required. For users of fluorescent object color measuring devices who do not have these color embellishing devices or standard light bulbs, the method specified in the annex to JIS Z 8717 is a difficult method. In particular, in a fluorescent object color measurement device that diffusely illuminates a sample with light from a light source via an integrating sphere,
The measurement of the sample surface illumination light is further complicated by the mutual reflection of the light between the inner wall of the integrating sphere and the sample surface. In addition, changes in the relative spectral efficiency of the integrating sphere due to deterioration of the inner wall material of the integrating sphere over time and the adhesion of dust can be a major cause of measurement errors.

Conventional fluorescent object color measuring devices have had the problem of having to periodically carry out this complex measurement.

On the other hand, regarding how to determine the relative spectral responsivity of the photoreceiver system,
There is no explanation in the annex, and users of fluorescent object color measurement devices should refer to the catalog values of the receiver, or use another receiver with a pre-specified value (hereinafter referred to as the standard receiver) and a microcurrent receiver. The only way to measure the relative spectral responsivity of the photoreceiver system was to use a meter to measure the relative spectral responsivity of the photodetector system, which had problems with measurement accuracy and simplicity. Furthermore, in a fluorescent object color measuring device that diffusely receives light from the sample surface via an integrating sphere, the light receiver composed of the light receiver and the integrating sphere is Measuring the relative spectral responsivity of a system becomes even more complex. In addition, changes in the relative spectral efficiency of the integrating sphere due to deterioration of the inner wall material of the integrating sphere over time and dust (=j) deposition can cause measurement errors, so conventional fluorescent object color measurement devices regularly There was also the problem of having to perform complex measurements.

The object of the present invention is to solve such conventional problems.

Measurement of relative spectral distribution of sample surface illumination light in an object color measuring device using white light illumination and spectroscopic observation method.

One objective is to provide a method that facilitates the measurement of the relative spectral responsivity of a light receiver or a light receiver system composed of a light receiver and an integrating sphere in a monochromatic illumination/non-spectral observation type object color measuring device.

[Structure of the Invention] (First Step for Solving the Problem) In order to achieve the second object, the first invention includes an illumination means for irradiating the sample surface with light from the light source X.

The light from the sample surface is guided to a light receiver via a monochromator, and an observation means is configured to measure the output of the light receiver for each set wavelength of the monochromator, and the reflected spectral radiance for each wavelength λ or μ. n types of fluorescent samples with known values of relative external fluorescence radiation efficiency Qn (μ) and relative spectral distribution F (λ) of fluorescent components, and one spectral radiance rate βw (x) with known values. A commonly used standard white surface and a commonly used standard white surface were sequentially placed on the sample surface, and the receiver output r(λ) for each wavelength was measured.

■ The receiver output obtained by installing a standard white surface on the sample surface is γW (λ), and the receiver output obtained by installing the i-th (i-1 to n) fluorescent sample is γl, + (
λ) (i=1 to n), γW (λ), γ8.
. ,, (λ), the spectral radiance factor β of the above commonly used standard white surface
w (X) and βt, X, i (λ) and the total spectral radiance factor Q of the i-th fluorescent sample, ,
, , Find (λ).

■ Next, SD the spectral distribution of the coloring light source whose value is known.
(μ), the relative external fluorescence emission efficiency of the i-th fluorescent sample Qn, , (μ).

From ND,1=ΣSo (μ)Qn,, (μ)ΔItμ, the original effective excitation efficiency ND,l of the coloring light source SD(μ) for the i-th fluorescent sample is determined.

■ Furthermore, the reflected spectral radiance rate βo, 1 (λ) of the i-th fluorescent sample, and the relative spectral distribution of the fluorescent component F+ (λ)
, total spectral radiance factor β1. .

(λ), effective excitation efficiency ND, and so on.

It is characterized by determining the spectral distribution Sx (λ) of the light source X from Sx (λ).

Further, the second invention includes an illumination means for irradiating the sample surface with light from a light source via a monochromator, and the light from the sample surface is guided to a photoreceiver, and the output of the photoreceiver is determined for each set wavelength of the monochromator. It constitutes an observation means for measuring, and each value of the reflected spectral radiance factor βo (λ), the relative external fluorescence radiation efficiency Qn (λ), and the relative spectral distribution of the fluorescent component F (μ) for each wavelength λ or μ is known. n types of fluorescent samples and a commonly used standard white surface with a known two-spectral radiance factor βw (x) were sequentially placed on the sample surface, and the receiver output r(λ) for each wavelength was measured.

■ The receiver output obtained by installing a common standard white surface on the sample surface is γW (λ) + the receiver output obtained by installing the 1st (i-1 to n) fluorescent sample is γ. , a, + (
λ) (i=1 to n), γW (λ), γ. ,
m', i (λ), the spectral radiance coefficient βW (λ) of the above-mentioned standard white surface, and the apparent spectral radiance coefficient β of the i-th fluorescent sample
,,,,, Find (λ).

■ Next, the reflected spectral radiance of the i-th fluorescent sample 2 degree factor βo, , (λ), the relative external fluorescence radiation efficiency Qn, , (
λ) 1 spectral radiance factor βo16.1.

The method is characterized in that the spectral responsivity S, (λ) of the photodetector system is determined from S, (λ).

(Function) According to the method for measuring the spectral distribution of a light source according to the first invention, the relative spectral distribution of the sample surface illumination light 8 can be measured without using a spectroradiometer or a standard light bulb, so it is representative of the conventional measurement method. J
It can be determined more easily than the method for measuring sample surface illumination light specified in the annex to IS Z 8717. In addition, due to the measurement principle of not distinguishing between the integrating sphere efficiency and the properties of the light source,
It can be similarly applied to a type in which light from a light source is diffused by an integrating sphere and irradiated onto the sample. From this, if it becomes necessary to check changes in the light source and integrating sphere over time, the relative spectral distribution of the sample surface illumination light on the container can be recalculated at any time.

Furthermore, according to the method for measuring the spectral responsivity of the photoreceiver system of the second invention, the relative spectral responsivity of the photoreceiver 13 or the photoreceiver system can be measured without using a standard photoreceptor or a microcurrent detector. It can be determined relatively easily than the measurement method.

Furthermore, since the measurement principle does not distinguish between the integrating sphere efficiency and the properties of the light receiver, it can be similarly applied to a type in which light from the sample surface is diffused by an integrating sphere and observed with a light receiver.

From this, if it becomes necessary to check changes in the light receiver and integrating sphere over time, the relative spectral responsivity of the light receiver system can be easily recalculated at any time.

Moreover, the optical system of the n1 determination method shown in the first and second inventions supplies a plurality of types of fluorescent samples with known values to a conventional fluorescent object color measuring device, and the optical system for the measurement data processing attached to the device. Since it can be easily modified by adding a program based on the measurement procedure shown in the present invention to a computer program, it can be applied to most conventional devices.

(Embodiment) FIG. 1 is a schematic diagram of an optical system showing an embodiment of a fluorescent object color measuring device equipped with means for estimating the relative spectral distribution of sample surface illumination light according to the first invention. In Figure 1, drawing number 1 is a light source such as a halogen bulb or a xenon lamp;
Reference numeral 2 represents a frame for mounting a sample to be measured, 3 represents a sample (fluorescent sample or commonly used standard white surface), 4 represents a monochromator, 15 represents a light receiver, and one or more parts 1 to 5 are attached to a cover 6, This constitutes a fluorescent object color measuring device 7.

First, the principle of measuring the relative spectral distribution of sample surface illumination light using this measuring device will be described.

The total spectral radiance factor of the n types of fluorescent samples 3 under the sample surface illumination light 8 generated by the light source 1 and the optical system (not shown) extending from the light [1 to the sample surface 3a is approximately expressed by a linear equation. be done.

5 β a, l (λ) − βo21 (λ) Here, β+, *, + (λ) is the sample surface illumination light S
The total spectral radiance rate of the first (i=1− to n) fluorescent sample 3 depending on the type of 8, β01. (λ) is the reflection spectral radiance factor for the reflection component of the first fluorescent sample 3, F
, (λ) is the relative spectral distribution of the fluorescent component, Qn, , (μ) is the relative external fluorescence radiation efficiency for the fluorescent component, SX (λ) and Sx (μ) are the relative spectral distribution of the sample surface illumination light 8, λ
and μ represents the wavelength, and Δμ represents the wavelength interval of integration (Σ).

By transforming equation (1), equation 2 (2) is obtained.

(2) N x I = ΣSx (μ)Qn,, (μ) A
μ“ (3
) Here, Nt,+ represents the relative value of the effective excitation radiation flux for the first fluorescent sample 3 at the sample surface illumination light 8 (Sx).

6 Ntl is a value independent of wavelengths λ and μ.

It becomes a proportionality constant regarding Sx (λ). For the inside of the cylinder, we can set it as N,, + -1.

Therefore, if the total spectral radiance factor β11, (λ) of the fluorescent sample 3 is measured with the fluorescent object color measuring device shown in FIG. 1, the values βo(λ) and Fl (λ) of the fluorescent sample 3 are The relative spectral distribution SX (λ) of the sample surface illumination light 8 can be estimated from equation (2) using .

The estimated value Sx (λ) at this time depends on the properties of the fluorescent sample 3 (ill). In order to estimate the sample surface illumination light 8 having average properties for n types of fluorescent samples 3, the coloring light [So (λ)] shown in Equation 1 (4) is used.
Equation (5) with the effective excitation efficiency Nol and the weight
Find from.

NO,l −ΣSo (μ)Qn,, (μ)Δμt'
(4) Here, SO(λ) is the colorimetric light 1, for example, the standard light D6
5 relative spectral distribution. if you can.

It is desirable that the illumination light has a relative spectral distribution similar to the sample surface illumination light 8 to be estimated.

Sx (λ) When n-1 is used in equation (5), estimated value S from equation (5) 1
x (λ) agrees with the estimate from equation (2).

In the wavelength range where the relative spectral distribution FI (λ) of the fluorescent component is 0, from equation (1), β+, x, l (λ) − β
o, , (λ) also becomes 0, and Equation 9 (5) cannot be calculated.
A method for estimating Sx (λ) in this wavelength range is shown below.

The estimated value obtained by equation (5) is expressed as SX・(λ).

Equation (1) can be expressed by the following equation.

Here, λ,1 to λ,2 are the wavelength ranges of Fl (λ)\0, and μ old is the value at the short wavelength end where Qn, , (μ) is 0.

The left side of equation (6) is expressed as a function N [1,il : (i=
1 to n), the right side Sx (λ) is the function S[1, μ]
= (μ-μQ1~λF, -Δμ), right side Q-,i(/
7) When Aμ is expressed as a function Q[μ+1], the relationship in Equation 1 (6) is expressed by determinant (7). When only one i-th fluorescent sample 3 is used as in equation (2), it becomes n-1. Here, one matrix N is the wavelength range λF as shown in equation (8).
The average value is 1 to λr2.

N-S Q (
7) Fl (λ) μ ” μ 01 (6) The function S[1, μ] can also be obtained from equation (9), but the slope with respect to the wavelength changes rapidly.

9 The value is quite different from the actual spectral distribution.

However, this value is applicable to fluorescent object color measurement.

Published by S-('QQ)'QN (9) Here, "Q is the transposition matrix of matrix Q ['Q(i.

μ)-Q(μ+1), ('QQ)-' is the inverse matrix of the matrix ('QQ).

Variation method of Takahama et al. [References: Kotabu Takahama, Yoshinobu Naya: Research on color rendering properties and metamerism (part 7) - A new method for synthesizing conditionally isochromatic object colors.

Reference magazine vol, 5B, No, 6+ pp, 29-8
B. (1972).

K, Takahama and Y, Nayata
nl: New Method or Genera
ting Metameric Stimuli of
' 0bjectColors, J, Opt, So
c, Am,, Vol, 62. No, 12°pI)
, 1516-1520 (1972)], S8
By determining (λ), a value that is relatively close to the actual spectral distribution can be estimated. The detailed method of determination will be described later in Step 6 of 1.

In this estimation method, measurements are performed using only an ordinary spectrophotometer and a fluorescent sample 3 whose value is known.

0 Also, as can be seen from the estimation method described above, in this measurement principle, the relative spectral distribution of light source 1 and the integrating sphere (figure omitted)
It is not treated separately from the relative spectral efficiency of . In other words, the estimation calculation described above can be similarly applied to a type of fluorescent object color measuring device (spectrophotometer) that irradiates the sample 3 with light from the light source 1 via an integrating sphere (not shown). can be expected.

The above is the measurement principle.

Next, the procedure for measuring and calculating the relative spectral distribution of the sample surface illumination light 8 using this measuring device 7 will be specifically described. Although the procedure is shown using all n types of fluorescent samples 3, estimation is possible even with only one type.

Step 1. Setting of Estimated Wavelength Range For all n types of fluorescent samples 3, the relative spectral distribution F(λ) of the fluorescent component is (λF1 to λP2).

The relative external fluorescence radiation efficiency Qn (μ) is n Wavelength range -1 where [Σ Qn,, (μ) ya 0] 1Lo: Find (μ., −μ.2).

The relative spectral distribution S, (λ) of the sample surface illumination light 8 in the wavelength range 1to+ to λr2 can be estimated from the following procedure. If the target wavelength range is not satisfied, use another fluorescent sample.

Step 2. Measurement of the receiver output with respect to the commonly used standard white surface.
While scanning the set wavelength λ of the monochromator 4, the output γW (λ) of the light receiver 5 is read. At this time, the receiver output γ1. It can be seen that the wavelength λ at which (λ) becomes O is the relative spectral distribution S of the sample surface illumination light 8 and the relative spectral distribution S (λ) becomes 0 at this wavelength, so it is excluded from the estimation calculations below.

Step 3. Measuring receiver output for fluorescent samples The value [βo, 1 (λ)] is placed on the measurement sample mounting frame 2.

Light receiving cuff + when n types of fluorescent samples 3 with known Fl (λ) and Qn, , (μ) Δμ] are sequentially installed
, y, l(λ): (i-1 to n) are determined.

Step 4. Jii of total spectral radiance factor The total spectral radiance rate of fluorescent sample 3 of "No. 1" is:

It is calculated from the following formula.

(10) Here, βW (λ) is the spectral radiance factor of the commonly used standard white surface 3 determined on a 1-1 scale under conditions equivalent to the geometric conditions of illumination and light reception used for measurement.

Step 5. Estimation of Sx (λ) in the wavelength range λP Calculate the measured value β in step 4 for the wavelength range λ obtained in step 1.
1. y, + (λ), and known data [βo, I (
λ), Fl(λ)] from Equation 9 (5) using
λ).

However, at the wavelength λ which becomes Fl(λ)-0.

3 F, (λ) Use the value for the j-th fluorescent sample 3 that is 0.

β1. x, + (λ) −βo, 1 (λ)”
fNn, I Fl (λ゛) [β1. y, l (
λ °)βo, + (λ')]Fl(λ))F,
(λ °) [β1. x, + (λ °) − βa
, i(λ ”)] [β1.., + (λ) − βo, +
(λ)] (11) Here, λ゛ is Fl (λ゛)K0 and F.

(λ°) is the wavelength at which Ki is 0.

Step 6. Wavelength range μ. Wavelength range μ obtained in Step 1 of estimation calculation of Sx (λ) in Sx (λ). Within the wavelength λ, less than 1, the measured value of step 4 β1. x, l (λ).

The estimated value Sx (λ) in step 5 and the known data [βo
, + (λ), Fl(λ), Qn, , (μ)] to estimate Sx(λ).

4 Procedure 6.1 Initial value setting function S For example, from step 1 and step 2, the short wavelength end μ becomes SX (λ)−0.
. When approximately known, the value of the linear expression is used as the initial value.

S x, In1lls+ [1+ μkoQ [μ,
i]: from [-Qn,,(,μ)Δμ].

Matrix B[i, j] = (i-1~n1 j-1
-n).

B-('QQ)-' (I8) Step 6
．． 3 Calculate the effective excitation efficiency N[1,il from the effective excitation efficiency formula (8).

Step 64 Error Calculation Initial value SX of Step 6.1, 1 using lnllllml
Find ΔN[1,il in the following equation.

AN [1, i] = N [1 j] S x, 11111111 Q (14) Step 6.5 Modify initial values The estimated value Sx (λ) is obtained from the following equation.

Sx (λ) −8x, lnllllml [1+ λ] + ΔN
B'Q (15) Step 6.6 Resetting the initial value If the value of Sx (λ) seems abnormal [such as a sudden change in the slope of Sx (λ) and O1), perform a moving average of 5 wavelength points. , with that value as the initial value (16) Also, Sx (λ) at the wavelength revealed by step 1 and step 2 is
Set to 0.

Using the above estimated value SX (λ), JISZ8717
It is possible to measure the fluorescent object color specified in .

Next, an actual measurement example based on this embodiment will be described.

The geometrical conditions of the optical system of the fluorescent object color measuring device 7 are O0
Illumination and 45° light reception.

As the light source 1, a light source similar to a xenon standard white light source defined in Japanese Industrial Standards JIS Z 8902 (xenon standard white light source) was used. As the relative spectral distribution SX (λ) of the sample surface illumination light generated by this light source,
The values determined according to the annex of JIS Z 871.7 are shown in solid lines in Figure 3. here.

The value represented by this solid line is regarded as the true value, and compared and evaluated with the estimated value (dotted line) obtained later.

For fluorescent sample 3, one light source fluorescence separation method (JIS Z
See 8717. ), and the following seven types of samples were used. Further, as the commonly used standard white surface 3, a pressure-bonded surface of barium sulfate powder was used.

(1) Fluorescent brightener-coated paper (2) Fluorescent red-coated paper (3) Fluorescent yellow-coated paper (4) Fluorescent green-coated paper (5) PVC color chart containing fluorescent yellow-red 7 (6) Fluorescent yellow-green and semi-white Transparent plastic (7) Fluorescent pink translucent plastic Reflection spectral radiance factor βo (λ), relative external fluorescence radiance efficiency Qn, , (μ), and relative spectral distribution of fluorescent components F'+ (λ) of each fluorescent sample 3 The values of are shown in FIGS. 4 to 6.

According to steps 1 to 6 described above, the relative spectral distribution Sx (λ) of the sample surface illumination light 8 is set in the wavelength range of 300 to 780 nm,
It was estimated using the value of 1onIl1 interval. The estimated value at this time is shown by a dotted line in FIG. Each value shown by a solid line and a dotted line in FIG. 3 is normalized so that Y of the tristimulus value of the light source color is 100.

The correlation value e2 between the true value and the estimated value is expressed by the following equation.

As can be seen from the comparison between the solid line and the dotted line in FIG. 3, when the measuring device 7 based on the present invention is used,
It can be seen that the relative spectral distribution of the sample surface illumination light 8 that approximates the true value can be estimated.

(17) 8 Here, + The standard deviation 1m is the number of wavelength points for calculating the correlation value e2,
The subscript j represents each wavelength point.

Next, as an example of fluorescent object color measurement, JISZ 8
In the case where fluorescent object color measurement is performed using the total spectral radiance factor synthesis method specified in 717, the effects of these true values and estimated values on the respective results will be described.

In order to measure the embellishment value under the standard light D65 using the total spectral radiance factor synthesis method using the same apparatus 7 as described above, the sample surface illumination light 8 in this apparatus is as follows:
Two types of color filters whose spectral transmittances are shown in FIG. 7 are suitable.

This is because the standard light D65 is not an actual illumination light.

It is difficult to actually measure the embellishment value under standard light D65. Therefore, the following two spectrometer measurement data for the following four types of fluorescent samples [References: It, former NATO, M, Nanjo and YNayat]
ani, Colorimetry and i
ts Accuracy 1nthe Meas
urement of fluorescent
Materialsby tbe Two M
onochroIIlator Methorl, C
o1or Res.

Appl,, Vol, IO, No, 2. pp, 84
-91. (1,985)] using JIS Z
This is a value calculated using the same calculation method as the fluorescence coloring error index specified in the annex to 871.7 (hereinafter referred to as the fluorescence coloring error index), and the true value and estimated value of the sample surface illumination light 8 are calculated for each measurement. Evaluate the impact on color values.

(1) Fluorescent red coated paper (R) (2) Fluorescent orange coated paper (0) (3) Fluorescent yellow coated paper (Y) (4) Fluorescent coated paper (G) Symbols RG in parentheses are 1 each This is the abbreviation for Fluorescent Sample 3.

When the true value of the relative spectral distribution of the sample surface illumination light 8 was used, the fluorescence colorimetry error index had the following value.

(CIEl, AI3 units) On the other hand, when the value of the relative spectral distribution of the sample surface illumination light 8 estimated based on the present invention was used, the fluorescence coloring error index had the following value.

(C1l, L A I3 , ++ in place) Therefore, the estimation method based on the present invention can practically provide a sufficient relative spectral distribution of the sample surface illumination light 8 necessary for measuring the body color of the fluorescent substance 1. This was confirmed.

FIG. 2 is a schematic diagram of an optical system showing an embodiment of the fluorescent object color measuring device according to the second invention. In Figure 2, drawing number 9 is a light source such as a halogen bulb or a xenon lamp;
10 is a monochromator, 111 is a frame for mounting a sample to be measured, 12
13 represents a sample (a fluorescent sample or a commonly used standard white surface), and 13 represents a light receiver, and one or more parts 9 to 13 are attached to a cover 14 and constitute a fluorescent object color measuring device 15.

First, the principle of measuring the relative spectral responsivity of the photodetector system according to this measuring device 15 will be described.

The apparent spectral radiance factor of the n types of fluorescent samples 12 observed under the photoreceiver system consisting of the photoreceiver 13 and the optical system (not shown) extending from the sample surface 12a to the photoreceiver 13 is 1.
It is approximately expressed by the following equation.

'132 βo1.1 (λ) = βo21 (λ) (18) Here, βo, m, i (λ) is the i-th (i = 1 to n) fluorescence that depends on the type of photoreceiver system S. The apparent spectral radiance factor of sample 12, βo, 1 (λ) is the reflected spectral radiance factor for the reflected component of the i-th fluorescent sample 12, Qn
, , (λ) is the relative external fluorescence radiation efficiency for the fluorescent component,
Fl (μ) is the relative spectral distribution of the fluorescent component, S, (λ) and S, (μ) are the relative spectral responsivity of the receiver system, λ and μ
represents the wavelength, and Δμ represents the wavelength interval of addition (Σ).

When formula (18) is transformed, formula 1 (19) is obtained.

(19) R1,l=ΣF+ (μ)S7 (μ) Aμ (
20) μ R11 is a value independent of wavelength λ and μ.

S, is a proportionality constant regarding (λ). For simplicity, R
,,,xl can be written.

Therefore, if the apparent spectral radiance factor β6.6 (λ) of the fluorescent sample [2] is measured using the measurement optical system shown in FIG.
The values βo, + (λ) and Qn, , (
Using λ), the relative spectral responsivity S,(λ) of the photoreceiver system can be estimated from equation (19).

The estimated values S and (λ) at this time depend on the properties of the (i-th) fluorescent sample 12. In order to measure the relative spectral responsivity with average properties for n types of fluorescent samples, it is determined from Equation 1 (21).

(21) In the wavelength range where the relative external fluorescence radiation efficiency Q−,+(λ) of the fluorescent component is 0, βC,s,+
(λ)−βo,l (λ) also becomes O, making it impossible to calculate Equation 9 (19) and Equation (21). S in this wavelength range,
The method for estimating (λ) is shown below.

The estimated value obtained by equation (19) is expressed as S, °(λ).

Equation (18) can be expressed as the following equation.

Qn (λ) where λ. 1~λ. 2 is the wavelength range of Qn, .

The left side of equation (22) is defined as a function R[1,i] : (i=
1 to n), the right side S, (λ) is the function S[], μ] :(
loose. 2+Δμ~μ, 2), and when F and (μ) Aμ on the right side are expressed as a function F[μ+ 1], the relationship in Equation 1 (22) is expressed by determinant (23). When only one i-th fluorescent sample 12 is used as in equation (19), 5 becomes n-1. Here, one matrix R has a wavelength range λ as shown in equation (24). 1 to λQ2.

The function S[1,μ] can also be obtained from equation (25), but the slope with respect to the wavelength changes rapidly.

The value is quite different from the actual spectral responsivity.

However, this value is applicable to fluorescent object color measurement.

S-('FF)-” FR(25) Here, lp is the transposition matrix of matrix F ['r(i.

μ)-F(μ,i)], ('FF)-1 is the matrix ('FF
) is the inverse matrix of

Applying the variation method of Takahama et al., S, (λ)
6, a value relatively close to the actual spectral responsivity can be estimated. The detailed method of determination will be described later in Step 6 of 1.

In this estimation method, measurements are performed using an ordinary spectrophotometer and one fluorescent sample with known values.

Further, as can be seen from the estimation method described above, in this measurement principle, the relative spectral responsivity of the light receiver system and the relative spectral efficiency of the integrating sphere (not shown) are not particularly treated separately.

In other words, the above-mentioned estimation calculation is similar to the fluorescent object color measuring device (spectrophotometer) 15 of the type that guides the reflected light from the sample surface 12a to the light receiver 13 via an integrating sphere (not shown). It is expected that it can be applied to

The above is the measurement principle.

Next, the procedure for measuring and calculating the relative spectral responsivity of the light receiving system according to this measuring device 15 will be specifically described. Although the procedure is shown using all n types of fluorescent samples 12, estimation is possible even with only one type.

Step 1. Setting the estimated wavelength range For all n types of fluorescent samples 12, the relative external fluorescence radiation efficiency Qn, , (λ) or (λQ1 to λQ2) and the relative external fluorescence radiation efficiency Q8 (μ
) calculates (μr1 to μF2).

Wavelength range λ. The relative spectral responsivity S7 (λ) of the photoreceptor system at 1 to 11F2 can be estimated from the following procedure. [”
If the target wavelength range is not satisfied.

Use another fluorescent sample.

Step 2. Measuring the receiver output with respect to a commonly used standard white surface. Place the commonly used standard white surface 12 on the measurement sample mounting frame 11,
While scanning the set wavelength λ of the monochromator 10, the output γW (λ) of the light receiver 13 is read.

Step 3. Measuring receiver output for fluorescent samples The number of samples to be measured j is the value [βo, +　<λ) in frame 11.

Receiver output γ when n types of fluorescent samples 12 with known Qn, , (λ)Δλ and Fi(lz)] are sequentially installed
(, s, 1(λ): (i=1 to n) is measured.

Step 4. Calculation of total spectral radiance factor No. 1: The total spectral radiance factor of the fluorescent sample 12 is calculated from the linear equation.

(26) Here, βW (λ) is the spectral radiance factor of the commonly used standard white surface 12 determined by L1 under conditions equal to the geometric conditions of illumination and light reception used for measurement.

Step 5. Wavelength range λ. The wavelength range λ obtained by estimation subtraction procedure 1 of S, (λ) in . Measured value β of step 1 for
o, +, + (λ), and known data 9 [βo, + (λ), Qn, , (λ)].
19) or estimate S and (λ) from equation (21).

Step 6. Estimation of S, (λ) in the wavelength range μ, within the wavelength range μm obtained in the old calculation procedure 1 and the wavelength λ. Measured value βo of 1 procedure 4 for 2 or more, 1.1 (λ).

The estimated value S, (λ) in step 5 and the known data [βo,
1 (λ), Qn, , (λ), F+(μ)],
Estimate S, (λ).

Step 6I Initial value setting function Sv, 1fillsl[1+X'co: (loose.20Aμ~7Zp2) is substituted with an appropriate initial value. For example, from step 2, S, (λ) ζ0 becomes the long wavelength end μ. When approximately known, the value of the linear expression is used as the initial value.

S t, In1ll*l [1-+ II ]0th-order matrix B [t, j]: <1-1 to n+J
−1 to n).

B-('FF)-' (28) Step 6.3 Calculate the matrix R[],i] by 81 from the formula (24) of R[1,il.

Step 6.4 Error Calculation Use the initial values ST, 1IllllI+ from Step 6.1 to find the linear equation AR[1,il.

AR[1,il =R[1,il Sv 1nll
lsl F (29) Step 6.5 The corrected estimated value S, (λ) of the initial value is obtained from the following equation.

S, (λ) = S v, lff1111m+ [1λ] + ΔR
B'F (30) Step 6.6 Resetting the initial value If the value of S, (λ) seems to be abnormal [S, (λ) < O, sudden change in slope, etc.], move the 5 wavelength points. Perform the average and use that value as the initial value for hand F [μ, i]: [
=F1 (μ)Aμ].

(31) Next, an actual measurement example based on this example will be described.

The geometrical conditions of the optical system of the fluorescent object color measuring device 15 are O
O illumination and 45° light reception.

A halogen light bulb was used as the light source 9. Further, the values of the relative spectral responsivity S, (λ) of the photodetector 13 used are shown by solid lines in FIG. Here, the value represented by this solid line is regarded as the true value, and compared and evaluated with the estimated value (dotted line) obtained later.

For fluorescent sample 12, one light source fluorescence separation method (JIS Z
See 8717. ) was priced in advance. The following seven types of samples were used. Further, as the commonly used standard white surface 12, a pressure-bonded surface of barium sulfate powder was used.

(1) Fluorescent brightener-coated paper (2) Fluorescent red-coated paper (3) Fluorescent yellow-coated paper (4) Fluorescent green-coated paper (5) PVC color chart containing fluorescent yellow-red (6) Fluorescent yellow-green translucent Plastic (7) Fluorescent pink translucent plastic Each prize photogenic sample] Reflection spectral radiance rate βo, 1 (λ
), the relative external fluorescence radiation efficiency Q8 (λ), and the relative spectral distribution F+ (μ) of the fluorescent components are shown in FIGS. 4 to 6.

According to steps 1 to 6 described above, the relative spectral responsivity S, (λ) of the photoreceiver system is set in the wavelength range 300 to 780 nm, l0n
Estimated using the value of i+interval. The estimated value at this time is shown by a dotted line in FIG. Each value shown by a solid line and a dotted line in FIG.
The values are normalized and shown so that the value at a wavelength of 600 nm is 1.

The correlation value e2 between the true value and the estimated value expressed by equation (■8) is approximately 1.
3, which seems to be a rather poor correlation, but this is
As can be seen from the comparison between the solid line and the dotted line in the figure, this is because the estimation accuracy is poor at wavelengths of 600 nm or more, which do not have much influence on the final measured value of the fluorescent object color. If a moving average is performed to smooth the estimated 3 values, there will be almost no problem with the measurement results. Therefore, it can be seen that by using the measuring device according to the present invention, it is possible to estimate the relative spectral responsivity of the photoreceptor system that approximates the true value.

(7) (Effect of the invention) As is clear from the above explanation, according to the method for measuring the spectral distribution of a light source of the first invention, the relative spectral distribution of the sample surface illumination light 8 can be measured using a spectroradiometer or a standard light bulb. JIS Z 8717, which represents the conventional measurement method because it can be measured without
It can be determined more easily than the method for measuring sample surface illumination light specified in the annex. In addition, due to the measurement principle of not distinguishing between integrating sphere efficiency and light source properties, there is also a type in which the light from the light source is diffused by an integrating sphere and irradiated onto the sample.

The same can be applied. From this.

If it becomes necessary to check changes in the light source and integrating sphere over time, the relative spectral distribution of the sample surface illumination light can be easily recalculated at any time.

Furthermore, according to the method for measuring the spectral responsivity of the photoreceptor system of the second invention, the relative spectral responsivity of the photoreceiver 13 or the photoreceptor system 4 can be measured without using a standard photoreceptor or a microcurrent meter. It can be determined relatively easily than the measurement method of . Furthermore, since the measurement principle does not distinguish between the integrating sphere efficiency and the properties of the light receiver, it can be similarly applied to a type in which light from the sample surface is diffused by an integrating sphere and observed with a light receiver. From this, if it becomes necessary to check the changes over time in the light receiver and integrating sphere, the relative spectral responsivity of the light receiver system can be easily recalculated at any time.

Moreover, the optical system of the measurement method shown in the first and second inventions is
Simply supply multiple types of fluorescent samples with known values to a conventional fluorescent object color measurement device, and add a program based on the measurement procedure shown in the present invention to the old computer program for processing measurement data attached to the device. Since it can be easily modified, it has the advantage that it can be applied to most conventional equipment.

i issue Rokuichi-←奔

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an optical system for implementing the measuring method according to the first invention, FIG. 2 is a schematic diagram of an optical system for implementing the measuring method according to the second invention, and FIG. Graphs of estimated values and true values of the relative spectral distribution of sample surface illumination light measured using the embodiments of the invention, and Figures 4 to 6 show the fluorescence used in each embodiment of the first and second inventions. A graph of the reflected spectral radiance factor, relative external fluorescence radiance efficiency, and relative spectral distribution of fluorescent components of a sample, and FIG. 7 shows a color filter when the embodiment of the first invention is applied to the total spectral radiance factor synthesis method. FIG. 8 is a graph of the estimated value and true value of the relative spectral responsivity of the photodetector system measured using the embodiment of the second invention. 1... Light source, 3... Sample (fluorescent sample or commonly used standard white surface), 3a... Sample surface. 4... Monochromator-15... Light receiver. 7... Fluorescent object color measuring device, 8... Sample surface illumination light 9...
...Light source, 10...Monochromator-12...Sample (
Fluorescent sample or commonly used standard white surface), 12a...sample surface, 13...light receiver. 15... Fluorescent object color measuring device 7 8 Wavelength (nm) Figure wavelength (nm) Figure wavelength (nm) Figure wavelength (nm) Figure

Claims (2)

[Claims] (1) Illumination means that irradiates the sample surface with light from the light source X;
The light from the sample surface is guided to a light receiver via a monochromator, and the observation means measures the output of the light receiver for each set wavelength of the monochromator, and the reflection spectral radiance factor β_o for each wavelength λ or μ is configured. (λ) Relative external fluorescence radiation efficiency Q_n (μ) and relative spectral distribution of fluorescent components F (λ)
n types of fluorescent samples, each of which has a known value, and a commonly used standard white surface, whose spectral radiance factor β_W(x) is known, are sequentially placed on the sample surface to determine the receiver output γ(λ) for each wavelength. [1] The receiver output obtained by installing a common standard white surface on the sample surface is γ_W (λ), and the receiver output obtained by installing the i-th (i = 1 to n) fluorescent sample is The output is γ_t_, x_,
When _i(λ) (i=1 to n), γ_W(λ),
γ_t_, x_, _i(λ), spectral radiance factor β_W(λ) of the above-mentioned standard white surface and β_t_, _x_, _i(λ) = β_W(λ)・γ_t
Total spectral radiance factor β_t_,_x_,_i of the i-th fluorescent sample from _,_x_,_i(λ)/γ_W(λ)
(λ), [2] Next, the spectral distribution of the colorimetric light source D whose value is known is SD
(λ), the relative external fluorescence radiation efficiency Q_n_,_i(μ) of the i-th fluorescent sample, and ▲There are mathematical formulas, chemical formulas, tables, etc.▼ From Find the effective excitation efficiency N_D_,_i under S_D(μ), [3] Furthermore, calculate the reflection spectral radiance rate β_o_,_i(λ) of the i-th fluorescent sample, and the relative spectral distribution of the fluorescent component F_
i(λ), total spectral radiance factor β_t_,_x_,_i(λ), effective excitation efficiency N_D_
A method for measuring the spectral distribution of a light source, characterized by determining the spectral distribution S_X(λ) of the light source (2) An illumination means that irradiates the sample surface with light from a light source via a monochromator, and an observation means that guides the light from the sample surface to a light receiver and measures the output of the light receiver at each set wavelength of the monochromator. reflected spectral radiance factor β_o(λ) for each wavelength λ or μ, relative external fluorescence radiation efficiency Q_a
(λ) and the relative spectral distribution F (μ) of the fluorescent component, respectively, with respect to n types of known fluorescent samples and the spectral radiance rate β
A commonly used standard white surface with a known W(x) is sequentially installed on the above sample surface, and the receiver output γ (λ) for each wavelength is measured. The obtained photoreceiver output is γ_W(λ), and the photoreceiver output obtained by installing the i-th (i=1 to n) fluorescent sample is γ_c_,_a_
,_i(λ) (i=1~n), γ_W(λ)
, γ_c_, _a_, _i(λ), the spectral radiance factor β_W(λ) of the above-mentioned standard white surface and β_c_, _a_, _i(λ) = βw(λ)・γ_c_
,_a_,_i(λ)/γ_W(λ) and the apparent spectral radiance rate β_c_,_a_, of the i-th fluorescent sample from
Calculate _i(λ) [2] Next, calculate the reflected spectral radiance factor β_o_, _i(λ) of the i-th fluorescent sample, the relative external fluorescence radiance efficiency Q_■_, _i(λ), and the apparent spectral radiance factor A method for measuring the spectral responsivity of a photoreceptor system, characterized by determining the spectral responsivity S_r(λ) of the photoreceptor system from β_c_, _a_, _i, and ▲There are mathematical formulas, chemical formulas, tables, etc.▼.