Patent Number: 6,254,264

Title: Lighting system for light guides

Abstract: An apparatus and method is disclosed which stabilizes the light incident a light guide end over a guaranteed operating lifetime of a lamp used to illuminate the light guide end. The apparatus and method minimize variation in illumination incident a light guide end without, for example, controlling the electrical input to the lamp. The invention is especially effective for light guides having a narrow outer diameter, and compensates not only for movement of a region of maximum luminosity, as occurs in lamps where the cathode is partially consumed during operation of the lamp, but also for the lamp luminosity decreasing with age.

Inventors: Koshikawa; Yutaka (Hachioji, JP), Tomioka; Makoto (Hachioji, JP), Suzuki; Takayuki (Hachioji, JP), Hasegawa; Akira (Musashino, JP)

Assignee: Olympus Optical Co., Ltd.

International Classification: F21V 8/00 (20060101); F21V 008/00 ()

Expiration Date: 07/03/2018