This standard specifies the color measurement method. When the viewing field is within the range of 1°~4°, the colorimetric function of the XYZ colorimetric system is used; when the color measurement is greater than 4° viewing field, the colorimetric function of the X10Y10Z10 colorimetric system is used. This standard applies to the color of reflected objects and the color of transmitted objects. It is not applicable to the color of objects containing fluorescence. GB/T 3979-1997 Measurement method of object color GB/T3979-1997 Standard download decompression password: www.bzxz.net
This standard specifies the color measurement method. When the viewing field is within the range of 1°~4°, the colorimetric function of the XYZ colorimetric system is used; when the color measurement is greater than 4° viewing field, the colorimetric function of the X10Y10Z10 colorimetric system is used. This standard applies to the color of reflected objects and the color of transmitted objects. It is not applicable to the color of objects containing fluorescence.
Some standard content:
CB/T3979-1997 This standard is a revision of CI3979-83 based on the relevant provisions of the publication of the International Commission on Illumination CIF No.15.2 (1986) Colorimetry. The technical content is consistent with the CIE "Measurement Methods of Object Color in Colorimetry". When this standard was revised according to the GB/11.11993 standardization work guide, relevant reference standards were added in the compilation of the standard; in the color measurement method, the calculation formula of the three color coordinates was supplemented; and new materials such as tetrafluoroethylene that can be used as marking plates were added. This standard is a basic colorimetry standard and should be used in conjunction with GB/T3977-1997 and GB/T3978-1994. This standard will replace GB3979-83 from the date of its effectiveness. This standard was proposed and managed by the National Technical Committee for Color Standardization. This standard was drafted by the Chinese Academy of Basic Sciences. The main drafters of this standard are Teng Xiujin, Zeng Xiaodong and Hu Weisheng. 1 Scope National Standard of the People's Republic of China Methods of measuring the colour of objects Methods of measuring the colour uf materlalsGB/T 3979—1997 GB397983 This standard specifies the method of measuring colour. When the viewing field is within the range of 1°-4°, the colour function of the XYZ colourimetric system (CIE1931 standard colourimetric system) is used. When the colour measurement is within the viewing field of 4°, the colour function of the XY,21 colourimetric system (CIE1964 supplementary standard colourimetric system) is used. This standard is applicable to the colour of reflected objects and the colour of transmitted objects. It is not applicable to the colour of objects containing fluorescence. 2 Referenced Standards The provisions contained in the following referenced standards constitute the provisions of this standard through their use in this standard. When this standard is published, the versions shown are valid. All standards are subject to revision. Therefore, parties using this standard should explore the possibility of using the following standards and newer versions. GB/3977-1997 Color expression method GB/T3978-94 Standard illuminant and lighting observation conditions G5698-85 Color terminology GB/7921--195 Color space and color difference formula 3 Definitions This standard contains the following definitions: 3.1 White standards White standards are measuring instruments used to transfer reflectance and colorimetric data, calibrate color measuring instruments, and perform color measurement. White standards can be divided into transfer standard white boards, working standard boards, and reference boards: 3.2 Transfer standard white boards are reflective white boards whose spectral reflectance is calibrated with a completely reflective diffuse body as the standard. They are used as the basic standard for calibration when transferring or measuring spectral reflectance values. 3.3 Working white standards Working white standards are special accessories for instruments. Their spectral reflectance values are stable and durable. They are reflective white boards used for regular calibration of color measuring instruments. 3.4 Reference white standards Reference white boards are installed in the reference beam window and serve as reference standards for calibration or measurement. The color spectrum in this standard is in accordance with G5698. 4 Classification of object color measurement methods 4.1 Spectral photometric colorimetry 4.2 Colorimeter method Approved by the State Administration of Technology on May 4, 1997 and implemented on October 1, 1997 5 Technical requirements of standard white boards 5.1 Transfer standard concave board The transfer standard concave board should meet the following conditions: GB/T 3979-1997 a) With good diffuse reflection characteristics, as close to a complete reflector as possible; b) The spectral reflectance in the wavelength range of 380nm-780nm is above 95%, and the spectral selectivity is small; c) With certain mechanical strength and optical stability; d) When the reflectance value changes by more than 0.5%, it must be recalibrated. The transfer standard whiteboard is required to be pressed with high-purity barium sulfate (BaSO,), magnesium oxide (Mg0) or polytetrachloroethylene (Halon) and other powder materials. 5.2 Working standard whiteboard The working standard whiteboard should meet the following conditions: 8) With good mechanical strength and optical stability; b) With good diffuse reflection characteristics; c) With a spectral reflectance in the wavelength range of 380nm-~780nm, the spectral selectivity should be above 80%, and the spectral selectivity should be small. Small selectivity: d) sticky to clear. Working standard plate can be made of porcelain white plate, porcelain white plate or opal glass and other materials: 5.3 Reference white plate The technical conditions and materials used for the reference plate are the same as those for the standard concave plate. 6 Spectral photometric colorimetry 6.1 Spectral photometer The spectrophotometer used for color measurement must meet the following conditions: a) The wavelength range is generally 380nm~780nm and at least 400t~70)nm; b) Passband half width: The passband half width of the radiation emitted by the exit slit of the spectrophotometer is generally not more than 10; c) The photometric accuracy should be within 0.5 of the full scale within the photometric range; d) The deviation between the nominal wavelength and the actual instrument wavelength does not exceed (.5nm, 6.2 Measurement method of reflected color 6.2.1 Geometric conditions of illumination and detection Should comply with GB/T 8978, Chapter 5. 6.2.2 Measurement of spectral reflectance ratio 6.2.2.1 Dual-light path measurement method a) Use a dual-light path spectrophotometer b) Place a reference white plate in the reference beam window ) Place the working standard plate in the measurement beam window and measure its spectral response reading. d) Replace the working standard white plate with the sample and measure the spectral response reading of the sample. e) Use formula (1) to calculate the spectral reflectance value of the sample: P() -= () r(a pr(a) Wherein: e(a)—spectral reflectance value of the sample: ()—spectral reflectance value of the working standard white plate! 1) Taking the measurement of spectral reflectance (a> under U/d conditions as an example, (l ()—spectral response reading of the sample: GB/T 3979—1997 \()—spectral response reading of the working standard white plate 6.2.2.2 Single optical path measurement method a) Use a single optical path spectral photometer. b) Measure the spectral response readings of the working standard white plate and the sample>) and (1). And calculate the spectral reflectance of the sample according to formula (1). c) To meet the measurement accuracy requirements, if necessary, the spectral reflectance of the sample (^) can be calculated according to the following linear correction formula (2): 1 - pw(a) · (1 -: 2f.) p(a) -r(a) 1- w(a).(1 -Df) - s(μ(a) -r() Where: u(a)- --Spectral reflectance of the working standard white plate; ow()--Spectral reflectance of the integrating sphere wall under the condition of 0/a:,--Percentage area of the first hole on the integrating sphere (accounting for the total area); fs--Percentage area of the sample hole. 6.2.3 Calculation method of tristimulus values The tristimulus values of the sample are calculated by the equal wavelength interval method, and the calculation wavelength range is ^=380nm~780mm. 6.2.3.1 The calculation formula of the tristimulus values XY.Z of the XYZ colorimetry system is as follows (3): X-ZS(A)E(A)R(A)AA Y =KS()P(A)R()AA Z =KS()E()R(A)AA Wu Zhong: Normalization coefficient, K- Relative spectral auxiliary power distribution of the standard light source (illuminant);)),()--XYZ Chromaticity function in the colorimetric system: R()--Spectral reflectance factor of the sample, including spectral reflectance and spectral radiance factor:--Wavelength interval. 6.2.3.2 The calculation formula of the three stimulus values Xu, Y, 2m of the XY12 colorimetric system is as follows (4): X: =K ES(A)Fa(A)R(A)A Yu=KIES(A)(A)R(A)A Zu -KL S(EHG)R(A)AA Ku—Normalization coefficient, K1:—S(a) y1s()100 Wu Zhong: (A).()), gram (A)--Chromaticity function in the XYZn colorimetric system. (2) (4) Weighting coefficients S()()S()(), S()() and S(A))S():(),The S()() value selects corresponding data according to the wavelength interval. Generally, 10 nm wavelength interval is used for chromaticity calculation. When high-precision measurement is required, 5 nm wavelength interval is used. When the measurement accuracy requirement is not high, 20 nm wavelength interval can also be used. The option coefficient values are shown in Table 2 and Table 3. 6.2.4 Calculation method of trichromatic color coordinates 6.2.4.1 The calculation formula of trichromatic color coordinates * and V in XYZ colorimetry system is as shown in formula (5): GB/T 3979-1997 y-x+Y+z -x+Yz 6.2.4.2 The calculation formula of blue color coordinate 18312 in X1Y1\Z1 colorimetry system is as shown in formula (6) Xie T=X#+Y+Zu y1o-X+Y+2 6. 3 Measurement method of transmission color 2n = X + Y+ Zfe = 1 — 3 — 3 6.3.1 The geometric conditions of illumination and detection shall comply with the provisions of Chapter 6 of GB/T3978. 6.3.2 Measurement of spectral transmittance (5) The spectral transmittance of the transmission sample shall be measured by using a palm gas or reference liquid of the same thickness as the sample as a standard for comparative measurement. 6.3.3 The calculation method of the stimulus value shall adopt the equal wavelength interval method. The range of calculated wavelength is =380m~-780nm. The calculation formula is as follows (7) and (8): XK s(()t()AA Y =K s(d)3()r(a)aa 2 --K SS(A)a(A)t(A)AA XIc =K,S(A)EI()r(A)A YIt =Ki, ES(A)VI(A)T(A)AA Zi. =K..FS(A)2n(A)(A)AA Where: (>)——Spectral transmittance of the sample. 7 Colorimeter method 7.1 Colorimeter The colorimeter must meet the following conditions: ) Use photoelectric integration element for detection, the spectral sensitivity of the system meets the color two numbers in the standard colorimetry system: and can directly measure the three stimulus values or color coordinates of the object. b) The measurement complexity of the selected medium gray should satisfy the color △F point = (.1. The color difference shall be calculated in accordance with GB/T 7921: 7.2 Measurement method 7.2.1 Geometric conditions of illumination and detection When measuring the mother reflective sample, the geometric conditions of illumination and detection shall be carried out in accordance with 6.2.1. When measuring the sample, the geometric conditions of illumination and detection shall be carried out in accordance with 6.3.1. 7.2.2 Graduation calibration ) Graduation calibration of measuring reflected color When measuring reflected color, the working standard white board is generally used to calibrate the instrument. When it is necessary to reduce the measurement error, the working standard color board with a spectral reflectance similar to that of the GB/T 39791997 sample can be used to calibrate the instrument. The tristimulus values of the working standard color plate should be measured by spectral photometry, and the geometric conditions of its illumination and detection should be consistent with the measurement conditions of the colorimetric instrument used. b) Graduation calibration of transmission color measurement When measuring transmission color, the air layer is generally used as the standard, and the instrument is calibrated according to the tristimulus values of the standard light source. When it is necessary to reduce the measurement error, the transmission working standard color plate (or reference liquid) with a spectral transmittance similar to that of the product can be used to calibrate the instrument. The tristimulus detection of the transmission working standard color plate should be measured by spectral photometry, and the geometric conditions of its illumination and detection should be consistent with the measurement conditions of the colorimetric instrument used. 8 Method of expressing measurement results 8.1 Expression of measured values The expression of measured values shall comply with the provisions of Chapter 4 of GB/T3977. 8.2 Additional records of measured values Additional records of measured values include: measurement method, standard light source type, geometric conditions of illumination and detection, sample placement, etc. 8.3 Records and forms of measurement results 8.3.1 The measurement results shall be recorded in the following ways: a) The measurement results using the harmonic photometric method shall record the spectral reflectance factor, tristimulus values and tricolor coordinates; b) The measurement results using the colorimeter method shall record the tristimulus values and tricolor coordinates. 8.3.2 The relevant additional records and symbols are shown in Table 1. Table 1 Additional records and symbols Measurement method Illumination and detection conditions Light photometric colorimetry Reflected color Transmitted color Reflected color Colorimeter Transmitted color Single light path method Double light path method Vertical/diffuse Diffuse/vertical Vertical/45° 45/vertical Direct Vertical/Vertical Direct/Diffuse Diffuse/Diffuse When measuring the color of an object, if the CIE1931 standard colorimetric observer data is used, no additional explanation is required; if the CIE1964 supplementary standard colorimetric observer data is used, it must be explained in the additional record. 8.3.3 Example of measurement result recording The measurement result can be recorded in symbolic form or in text. The following are examples: Example 1 The measurement base is 1) standard light source, using the direct/diffuse lighting detection condition, the measurement method is the double light path method in the spectral photometric colorimetric method, and the wavelength interval is 10nm: use the light-3 type photoharmonic colorimeter. The measurement results are as follows: Yrsr28 50.T 0. 583 4.y 0. 272 30/d Straight 10 light 3 plastic spectrophotometer Example 2 The measurement conditions are C standard light source. The illumination detection conditions of heavy straight/45° are adopted, and the colorimeter method of JQ-1 photoelectric colorimeter is adopted: Measurement result record: 98.4.2104.9 0/45PJQ-1 photoelectric colorimeter GB/T 3979—1997 699°0 trr(r)s —1997 CB/T 3979 000 *0 (000*0 000 *0 000-001 100'℃ 220°0 S01811 E 91-0 lao '0 000 -0 000“0 878*601 A(nra) GB/T3979—1997 Table 2.2 Weighting coefficient (standard illuminator A, wavelength interval△=5nm)sca) 0- 515 6 0.469 center 0, 000 3 0: 237 5 0- 519 6 : 0. 681 3 SA)z(A) 2: 558 1 GB/T 39791997 Table 2.2 (End) s()a(A) 6-335 2 0-5368 109.851 0 3 -773 4 , 362 5 0- 195 8 0-000 0 100. 000 0 心, Q0心心 35. 581 9 GB/T 3979-1997 Table 2.3 Weighting coefficients (standard illuminant C. wavelength interval A1=5nm) se(a) 1:392 4 - 316 9 3-661 4 S()z(A) 10. 334 7 7- 486 1 6-0718 0- 194 2 GB/T 3979--1997 Table 2.3 (end) 3-8865 3- 535 0 0- 196 4 C)- 002 9 S(A)y(a)wwW.bzxz.Net . 092 9 0- 000 6 C- G 3 0 000 0 - 00 0 100.000 0 S(a)(a) 0,00 0 118- 226 5 Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.