A self-light-emitting indicating apparatus including an enclosure formed by combining a pair of opposing semi-tubular bodies, each having first and second support members positioned at both ends; first and second panels fixed on the first and second support members respectively, at least one ...http://www.google.ca/patents/US5727103?utm_source=gb-gplus-sharePatent US5727103 - Optical leakage preventing apparatus and self-light-emitting indicating apparatus using the same 
