Design and optimization of long-wavelength pass filter in 3D imaging system

In this paper, a kind of long wave pass filter in 3d imaging system is proposed. When the ray incidence Angle is $0\sim 30^{\circ}$ on K9 glass, the long wave pass filter can meet the requirements of 330-370nm transmittance less than 1%, 400- 625nm transmittance more than 93% and 720-1100nm transmittance less than 1%. The variable scale optimization function and needle optimization function of TFCalc film system design software were used to design the film system. The results show that the average transmittance of 330-370nm band film layer is 0.861%, the average transmittance of 400- 625nm band film layer is 93.152% and the average transmittance of 720-1100nm band film layer is 0.94263%. The design results meet the technical requirements.