Laser drive device that drives laser diode, method of controlling the same, and storage medium

A method of controlling a laser drive device that drives a laser diode, comprising:

• detecting a light amount of a laser beam output from the laser diode, using a detection unit;
• controlling the light amount of the laser beam output from the laser diode to a plurality of set light amounts by controlling a drive current supplied to the laser diode according to a detection output from the detection unit;
• calculating a threshold current according to the detection output from the detection unit and a drive current supplied to the laser diode;
• and
• switching and selecting the plurality of set light amounts, comparing a plurality of threshold currents with each other which are obtained from said calculating the threshold current with respect to the plurality of set light amounts, respectively, and determining a set light amount among the plurality of set light amounts as a determined set light amount for use in light amount control of the laser diode according to whether a difference in threshold currents corresponding to the determined set light amount and another set light amount among the plurality of set light amounts is not less than a predetermined value.

A non-transitory computer-readable storage medium storing a computer-executable control program for causing a computer to execute a method of controlling a laser drive device that drives a laser diode,

• wherein the method comprises:
• detecting a light amount of the laser beam output from the laser diode, using a detection unit;
• controlling the light amount of the laser beam output from the laser diode to a plurality of set light amounts by controlling a drive current supplied to the laser diode according to a detection output from the detection unit;
• calculating a threshold current according to the detection output from the detection unit and a drive current supplied to the laser diode;
• and
• switching and selecting the plurality of set light amounts, comparing a plurality of threshold currents with each other which are obtained from said calculating the threshold current with respect to the plurality of set light amounts, respectively, and determining a set light amount among the plurality of set light amounts as a determined set light amount for use in light amount control of the laser diode according to whether a difference in threshold currents corresponding to the determined set light amount and another set light amount among the plurality of set light amounts is not less than a predetermined value.