OPTICAL WIRELESS COMMUNICATION EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To provide a stable radio equipment without increasing the transmission power of a light signal by providing one double convex lens for a receiver and permitting the focal distance of the double convex lens and the diameter of the lens satisfy a specified relation. SOLUTION: A receiver receives light from a light source body 3c constituted of plural light-emitting elements. The center axis (optical axis) 1 of light is ideally a straight line passing through the center point of a light source body 3a and the lens 2 and a dotted line 7 shows the stretch of light transmitted from the light source body 3a. Since the distance between the light source body 3a and the lens 2 is larger than the diameter of the lens, light which is made incident on the lens 2 from the light source body 3a is only the parallel light of the optical axis 1. The lens 2 is double convex lens and the focal distance (f) of the double convex lens 2 and the diameter (d) of the lens 2 satisfy the relation of 0.6d<=f<=1.2d. Thus, the equipment can be used with good conditions that the light reception intensity of light-receiving elements is made to be the largest and the focal distance can be made minimum.