LIGHT SOURCE DEVICE FOR OPTICAL TRANSMISSION SYSTEM COMPRISING LIGHT GUIDE

摘要

PROBLEM TO BE SOLVED: To obtain a required illumination distribution on a light receiving face of a light guide so as to reduce a loss in the light guide by appropriately condensing a reflected light beam on the light receiving face of the light guide. SOLUTION: This device comprises a light source 11 facing to a light receiving face 17 formed at an end of a light guide and a reflector having an inner reflective surface 14 on which light from the light source 11 is reflected so that a light beam incident on the light receiving face 17 of the light guide is formed. The inner reflective surface 14 of the reflector consists of a number of ringed reflecting areas formed along circumferences of closed curves defined on a number of planes perpendicular to a line connecting the center of the light receiving face 17 and the light source 11. The reflecting areas are smoothly joined each other and have respective condensing characteristics wherein respective rays reflected on the different reflecting areas reach different areas on the light receiving face 17 while all the rays have respective incident angles to the light receiving face 17 such that the incident rays are totally reflected in the light guide.