A Measurement Method for Equivalent Spectral Transmittance of a Spherical Photometer
This paper proposes an in-situ measurement method for equivalent spectral transmittance ratio of a spherical photometer.While using a spherical photometer to measure the total luminous flux of the light source,spectral mismatch correction is required due to the spectral difference between the standard lamp and the tested lamp.The equivalent spectral transmittance ratio is one of the input parameters for calculating this correction.To avoid disassembling and installing of the cosine corrector glass and the coating sample,an in-situ method is used to measure the equivalent spectral transmittance by comparing the spectral differences between outlet spectral irradiance and the standard lamp at the center of the integrating sphere.Applying this method,a spherical photometer is used to test the total luminous flux of white,red,green,and blue LED samples.The results are compared with those obtained from a goniophotometer.Experimental data showed that both results are consistent within the uncertainty range,validating the feasibility of the proposed equivalent spectral transmittance ratio measurement method.
万方数据
维普
