Angled illumination tube

Abstract

An angled illumination tube is capable of reducing a dark spot behind the reflector, while illuminating the tube uniformly over the length of the tube. The tube is used in combination with a light source providing a light beam and comprises an angled transparent tubular conduit having a first end and a second end on opposite longitudinal ends of the conduit. The conduit has a bend between the first and second longitudinal ends, and is used with the first end receiving the light beam from the light source in order to guide the light beam along the length of the conduit. A reflector is disposed within the bend to reflect the light beam from the first end to direct a reflected light beam towards the second end. The reflector defines an incident light axis along which the light beam is guided to the reflector, and a reflected light axis along which the reflected light beam is directed to said second end. The reflector is composed of a plurality of mirrors arranged in a parallel array along a bisector that divides an included angle between the incident and reflected light axes at an angle (.theta.) with respect to the incident light axis. Two adjacent ones of the mirrors are spaced at a fixed distance (d) along the bisector and of uniform length (L) measured within a plane including the incident and reflected light axes. The mirrors are arranged to satisfy the following relation: ##EQU1##

Dependencies are inferred from the claim text.