Designing and evaluating athermal optical antenna for airborne LIDAR system

In the airborne LIDAR system, it is required that optical antenna is light weight, robust and insensitive to temperature in flight. This paper presents the designing of athermal optical antenna with CFRP (Carbon Fiber Reinforced Plastic) and the result of evaluating the optical performance with Shack-Hartmann wavefront sensor. In the range of 15~25 degrees Celsius, The change of RMS wavefront error was ± 0.006 RMS in wavelength unit of 1.55 micrometer with CFRP spacer, but on the other hand ± 0.042 RMS in wavelength unit of 1.55 micrometer with Aluminum spacer. Consequently, we demonstrated the validity of the passive athermal optical design.