Abstract: A method and apparatus is disclosed for operating a multi-color LED domelight employing color blinking as a visibility enhancement technique. In the method, light is emitted having a first color, upon which light is intermittently emitted having a second color during the step of emitting light having a first color. All light is emitted through a common light-emitting surface defined by a domelight housing. The intermittent blinking of a different color light during or between the emission of the first color light enhances the visual perceptibility of the domelight device. In one embodiment, the first color is substantially red and the second color is substantially yellow. In another embodiment, the first color is substantially green and the second color is substantially magenta. In yet another embodiment, the first color is substantially blue and the second color is substantially white.

Abstract: The twin sensor laser probe and the method are for absolute depth measurement of two distinct points on an object surface. Two light beams emitted by a light source are directed toward the object surface at acute angles relative thereto, to illuminate two distinct points of the object surface having positions depending on depth thereof. The light beams extend on opposite sides of a plane separating the probe in two longitudinal portions and intersecting the object surface. Two optical sensors are positioned above the object surface and extend on the opposite sides of the plane respectively. The two illuminated points are imaged on the sensors by a lens and two parallel mirrors optically arranged to fold the fields of view of the optical sensors. The signals produced by the sensors provide information for the absolute depth measurement of the two points.