The article mainly focuses on the new research abeut incident angle of optical signal and optical device characteristics.By combining experimental and theoretical methods

discussed the dispersion and return loss caused by the optteal signal which the transmission rate is 2.5Gb / s in the 1550nm wavelength enter FA end face made by the single mode fiber which the model is g.652 and the length is 1000KM at different incident angles respectively.Through changing the incident angle of the laser

to obtain the total dispersion coefficients of optical signat at the outpul terminal and the return loss of optical signal at the input terminal at the same time.The results showed that the total dispcrsion coefficients of optical signal can be minimized and return loss can be rnaximized when the fiber array made by g.652 single-mode liber transmit al the incidenl of 8 degrees angle.It plays an important role in the optical communications research

especially in the targe-scate promotion of FTTH engineering applications.It laid solid theoretical foundation ol optical devices R & D business.PLC optical device grinding production business

AWG

DWDM-PON optical device testing business and other aspects of the business.Which also has a positive role in promoting the development of optical fiber transmission and optical devices.