Fig. 1. Schematic diagram of BTDF geometry

Fig. 2. Distribution characteristics of transmission and scattering angle. (a) Ground glass; (b) Engineering diffuser

Fig. 3. Structure of scattering sampling attenuation unit

Fig. 4. Comparison of the simulation results of the scattering angle characteristics of transmitted materials. (a) Ground glass; (b) Engineering diffuser

Fig. 5. Three-dimensional spatial distribution of the emitted light from the combined sampling attenuation structure

Fig. 6. Experimental optical path diagram of transmission and scattering characteristics of sampling materials

Fig. 7. Grid processing of experimental spots. (a) Acquired spot image; (b) Gridded spot image

Fig. 8. Comparison of simulation and experiment of transmitted scattered light distribution. (a) Single piece of ground glass; (b) Combin-ation of ground glass and engineering diffuser

Fig. 9. Response linearity of combined scattering sampling attenuation structure