Patent ID: 6897623
Filing Date: 2005-05-24
Classification: H05B

Abstract:
1. An electric power supply system for LED lighting unit that constitutes a work imaging system to take an image of a work as an object to be taken by an imaging device such as a CCD camera and to process the image so as to inspect a flaw formed on a surface of the work or to read a mark such as an alignment mark, and characterized by comprising an LED lighting unit that has an LED conducting circuit including at least an LED and a resistor for type identification having resistance corresponding to a specification or a characteristics of use of the LED conducting circuit and that irradiates light on the work and an electric power supply unit that has a type identify portion consisting of a resistor measuring circuit that can be connected with the resistor for type identification and a constant current control portion that supplies a control current in an arbitrary range not over the maximum allowable current of the LED conducting circuit set based on the resistance of the resistor for type identification measured by the type identify portion to the LED conducting circuit.