Patent ID: 6943333
Filing Date: 2005-09-13
Classification: G01J

Abstract:
1. A lighting arrangement for providing a predetermined illumination on an object illuminated by a varying ambient light, comprising: a light source disposed in optical proximity to the object for illuminating the object with a supplied light of a certain intensity in response to a light control signal; an illumination sensor disposed in optical proximity to the object for detecting the total illumination resulting from both the supplied light and the ambient light, the illumination sensor producing an illumination signal proportional to the total illumination; and a light controller electrically connected to the illumination sensor and the light source, the light controller having a negative feedback circuit for producing the light control signal in response to the illumination signal so as to maintain the predetermined illumination on the object, the light controller further including an input configured to receive from an external device an illumination command specifying the predetermined illumination.