Patent ID: 7352786
Filing Date: 2008-04-01
Classification: H01S

Abstract:
1. An apparatus for driving a light emitting element in response to input data, the light emitting element caused to emit light by flowing a direct current, the apparatus comprising: a voltage source; and a switching section disposed between the voltage source and the light emitting element and controlled on a basis of the input data, wherein, (1) when the switching section connects the voltage source to the light emitting element, a resistance value from an output end of the voltage source to a drive end of the light emitting element is smaller than an internal resistance value of the internal resistor of the light emitting element, (2) the voltage source has a negative feedback loop that negatively feeds back an output and amplifies a predetermined input voltage, (3) the voltage source has a buffer amplifier and a capacitance section at an output of the buffer amplifier; and (4) the capacitance section of the voltage source has greater capacitance than the capacitance value of parasitic capacitance of the light emitting element, when being observed from the switching section.