A document discusses the Ultra Compact Cloud Physics Lidar, a biaxial lidar with a narrow receiver field of view. It requires tight optical alignment between the transmitter and receiver paths while flying on various aircraft over various temperatures and in the presence of vibration. To achieve optical crossover as close to the lidar as possible, the transmit and receive telescopes must be built very closely to each other.
In this innovation, novel packaging has been used to achieve both objectives and is applicable to any small biaxial lidar with narrow receiver field of view and short crossover distance requirements. The alignment and close spacing requirements have been solved by cutting the transmit and receive telescope tubes from a single piece of metal. This ensures good heat flow between the optical systems, which limits thermally induced misalignments. This also ensures close mechanical coupling, which limits vibrationally induced misalignments. The transmit and receive optical axis are aligned by moving the source on the transmit telescope focal plane.
This work was done by David Lawrence and Yunhui Zheng of Sigma Space for Goddard Space Flight Center. GSC-16120-1