Detector input dark current offset calibration in an optical disk drive

An optical disk drive, comprising:

• an optical pick-up unit;
• an analog processor coupled to receive input signals from detectors in the optical pick-up unit and provide digital signals, the analog processor including an input signal gain and an input signal offset;
• at least one processor coupled to receive the digital signals, the at least one processor calculating control signals;
• and
• a driver coupled to control positions of the optical pick-up unit in response to the control signals,
• wherein the at least one processor executes an algorithm that calibrates the input signal offset, the algorithm including instructions that
• sets a laser in the optical pick-up unit off, and
• sets the input parameter offsets such that the digital signals are at predetermined values.

A method of correcting for thermal drift, comprising:

• setting laser power off;
• averaging digitized input signals over time with operating parameters set for read mode to form read mode offsets;
• averaging digitized input signals over time with operating parameters set for write mode to form write mode offsets;
• and
• adjusting input offsets for the read mode offsets and the write mode offsets.