Optical wavelength conversion device, an optical wavelength converting method, and an image forming apparatus using the same

PROBLEM TO BE SOLVED: To provide a light wavelength conversion device for stably controlling high gradation without depending on a modulation signal pattern and to provide a light wavelength conversion method and a control method of the device. SOLUTION: The light wavelength conversion device comprises a DBR laser 101, a light wavelength conversion element 104 which makes a fundamental wave light emitted from the DBR laser 101 incident, and outputs second harmonic light, and a control means 109 controlling the DBR laser 101. The control means 109 injects constant driving current different in two time domains to either an active region 101a or a DBR region 101c, injects binary driving current in the two time domains to the other region when one period of driving current is divided into the two equal time domains, and adjusts a current value of driving current and injection time so that a sum of heating values generated in one period becomes almost constant at every period by driving current injected to the other region. COPYRIGHT: (C)2007,JPO&INPIT