GB/T 24981.1-2020Test methods of rare earth long afterglow phosphors—Part 1: Determination of emission dominantpeak and chromaticity coordinates (English PDF)

3.1 Spectral radiation tester

The spectral radiation tester shall meet the following conditions:

a) Wavelength accuracy: ±2 nm;

b) Accuracy of chromaticity coordinates: ±0.001;

c) Spectral range: 380 nm ~ 720 nm.

3.2 Excitation light source

The 365 nm ultraviolet low pressure mercury lamp is equipped with a color filter; the peak transmittance of the filter shall be greater than 10%; transmittance of 380 nm ~ 720 nm shall not be greater than 0.01%; the radiation intensity stability of 365 nm shall be better than 0.2%/10 min, otherwise, it shall be compensated.

3.3 Sample pan

The sample pan is black, with an inner diameter of 20 mm and a depth of 3 mm.

4.1 Test conditions

4.1.1 Ambient temperature: 22 °C ~ 27 °C

4.1.2 Relative humidity: <=70%

4.1.3 During the measurement process, in addition to the specified excitation light source, there shall be no stray light interference such as visible light or ultraviolet light.

4.2 Instrument calibration

Be stable for 10 min ~ 30 min according to the requirements of the instrument. Refer to the instrument manual to calibrate the instrument.

4.3 Test

4.3.1 Load the sample into the sample pan; compact and make the surface flat.

4.3.2 Place the sample pan in the sample chamber to be excited, so that the sample is excited by the ultraviolet lamp.

4.3.3 Irradiate the sample under an ultraviolet lamp for more than 1 min; scan from the 380 nm ~ 720 nm wavelength range; measure the relative spectral power distribution of the sample and the peak wavelength of the emission dominantpeak. The emission dominantpeak is expressed by the peak wavelength (lambda).

4.3.4 According to the measured relative spectral power distribution, calculate the chromaticity coordinates (x, y) with reference to CIE 1931.

4.3.5 Repeat the test 3 times for a sample; take the arithmetic mean value. […]