Fig. 1. Phase vector height diagram of diffractive optical elements

Fig. 2. The relationship between the diffraction efficiency of DOE and (a) the number of steps (m=1), (b) the diffraction order (N = 8)

Fig. 3. Dispersion characteristics of DOE

Fig. 4. The filtering characteristic diagram of DOE combined with single mode fiber and multimode fiber

Fig. 5. The relationship between filter half width and fiber core diameter

Fig. 6. Coil-in energy analysis of traditional lens combined with single-mode fiber and DOE combined with single-mode fiber

Fig. 7. (a) Concept map of laser radar ranging system based on DOE receiving; (b) DOE with a diameter of 50 mm

Fig. 8. (a) The receiving optical path coupled to the 0.5 nm filter; (b) The specific structure diagram of the optical fiber end and the APD target surface

Fig. 9. Distance measurement result

Fig. 10. Experimental results. (a) Single-mode fiber; (b) Single-mode fiber (with 0.5 nm filter); (c) Multimode fiber; (d) Multimode fiber (with 0.5 nm filter)