Fig. 1. Diagrams of focus imaging of lobster eye lens. (a) Diagram of structure; (b) principle of focus imaging

Fig. 2. Schematic of fringe reflection measurement

Fig. 3. Setup for fringe reflection surface measurement

Fig. 4. Fringe intensity images from LCD screen. (a) X direction; (b) Y direction

Fig. 5. Measurement surfaces of lobster eye lens. (a) Measured fringe reflection; (b) testing results of Zygo interferometer

Fig. 6. Surface data of lobster eye lens obtained by repeated measurements based on fringe reflection method

Fig. 7. Normalized curve of surface slope distribution

Fig. 8. Simulated imaging results at focus of 375 mm under different conditions. (a) Ideal condition; (b) condition with surface error

Fig. 9. Light intensity distribution of focal spot oflobster eye lens