1.The observation angle of the instrument α is 1.05 °; angle of incidence β is 88.76 ° (complementary angle of 1.24)

2.The color temperature of the light source is 2856K±50K (CIEA light source) 

3.The detector is a silicon diode + V (N) corrector, corrected by the filter to meet the CIE standard photometric observer spectral light visual efficiency V (N) requirements 

4.Retroreflection coefficient (R'') measurement range of 0 ~ 1999 mcd lx-1 m-2