Imaging Analysis of Photonic Integrated Interference Imaging System Based on Compact Sampling Lenslet Array Considering On-Chip Optical Loss

Abstract

A photonic integrated interference imaging system (PIIIS) is a computational imager based on Michelson interference and photonic integrated circuits (PICs). In this paper, a PIIIS based on a compact sampling lenslet array that can sample the zero spatial frequency through a single lenslet, densely sample the frequency in the azimuth direction through the configuration of a hierarchical multistage lenslet array, and continuously sample the frequency in the radial direction through a Langford sequence is proposed. We introduce the design process of the compact sampling lenslet array in detail and simulate the imaging of the system. The simulation results demonstrate that the lenslet array can effectively improve the imaging quality of a PIIIS. In addition, we design a silicon PIC and a silicon nitride transition PIC that match the compact sampling lenslet array and simulate the imaging of the system under the influence of the on-chip optical loss of PICs (the average interference baseline loss is 15.4 dB at 1550 nm). The results show that on-chip optical loss mainly affects the brightness and contrast of the reconstructed image but has little effect on the structure.