Patent ID: 6347105
Filing Date: 2002-02-12
Classification: H01S

Abstract:
A laser control apparatus comprising:a light source; light amount detecting means for detecting an amount of light emitted from said light source and outputting a light amount detection value; sample and hold means for sampling and holding said light amount detection value; light amount control means for carrying out a negative feedback control of said light amount according to a difference between said light amount detection value and a light amount reference value during a control period in which said light source emits the light and in which said sample and hold means is in a sample state; first comparing means for comparing said light amount detection value with a maximum permissible light amount and outputting a first effective comparison output during a period of said negative feedback control; current detecting means for detecting an electric current flowing to said light source and outputting a current detection value; current detection value holding means for holding an increased value of said current detection value during the period of said negative feedback control; second comparing means for comparing said increased value with a present value of said current detection value during periods except for the period of said negative feedback control and outputting a second effective comparison output; and current interrupting means for interrupting the current flowing to said light source in accordance with said first or second effective comparison output.