Analysis of the Characteristics of Optical-Fiber Image Slicers

Using image slicer is an important method to effectively improve the light transmission of an astronomical high-resolution spectrograph.At present, Bowen, Bowen-Wairaven, Richardson, and optical-fiber image slicers are the major types of image slicers.This paper considers optical-fiber image slicers using 40/45μm, 50/55μm, 60/65μm, and 70/75μm High-OH core fibers, and calculates the light transmission efficiencies of the HiRES (High-Echelle Spectrograph ) to be mounted on the LAMOST (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope) both with and without a fiber image slicer.This paper also analyzes the relation between the accuracy of position matching to the front image and the light transmission efficiency for an optical-fiber image slicer.The results show that an optical-fiber image slicer can effectively improve the light transmission of an astronomical high-resolution spectrograph, and have the advantages of little defocusing, simple structure, easy fabrication, and easy installation.