Research progress on ultra-small self-focusing optical fiber probe

Gradient-index(GRIN) fiber probe is an all-fiber ultra-small optical lens, which has broad application prospects in endoscopic image detection in small spatial tissues such as cardiovascular. However, its development lacks a systematic theoretical system. This paper discusses the key issues of the design, fabrication and performance testing methods of the probe. Based on the characteristics parameters of GRIN fiber probe, comparative analysis is conducted between the analytical method and numerical simulation methods. An integrated high precision optical fiber welding and cutting device is presented for the fabrication of ultra-small GRIN optical fiber probe. In addition, the method and device for detecting the focusing performance of ultra-small GRIN fiber probe are analyzed. As a result, a system method for design, fabrication and performance testing is provided for the research of GRIN fiber probes.