Back to results
US 6,717,526 B2Granted
Light degradation sensing LED signal with light pipe collector
AssigneeGELcore, LLC
InventorsPatrick Martineau, Jean-Simon Bourgault, Eden Dubuc
Life of this patent
Estimating the term…
Abstract
An LED signal with an LED light pipe collector and intelligent light degradation sensor. The light pipe collector captures LED light normally lost in a generally horizontal direction and redirects it into a generally vertical direction through use of total internal reflection. The light degradation sensor monitors LED signal light output. When light output degrades to a preset level, an electrical circuit triggers a disabling short circuit to deactivate the LED signal.
Claims50
An LED signal comprising:
- a housing having an interior area and an open end,
- at least one LED,
- a light sensing means;
- a comparator means;
- said at least one LED arranged and configured within said interior area of said housing;
- said light sensing means located within said interior area of said housing, having an output value relative to a light level within said housing;
- said comparator means comparing said output value to a reference value;
- if said output value is below said reference value said comparator initiates a disablement means.
5 more elements
An LED signal comprising:
- a housing having an interior area and an open end;
- at least one LED;
- a light pipe collector for use with at least one LED comprising:
- an optical member composed of light transmissive material,
- at least one total internal reflection surface, and
- a receiving chamber for receiving said at least one LED;
- said at least one LED emitting light in a main direction and a non-main direction;
- said at least one LED arranged and configured within said interior, of said housing;
- said total internal reflection surface operating to redirect said non-main direction emitted light to said main direction through total internal reflection.
6 more elements
Dependencies are inferred from the claim text.