Apparatus, method, and computer program product for controlling laser wavelength stability

A method for stabilizing a wavelength of a laser, comprising:

• providing a laser that generates a predetermined wavelength when the laser operates at room temperature, the predetermined wavelength being offset from a specific wavelength, the laser has a controlled wavelength range, the wavelength range having a first wavelength as the upper boundary and a second wavelength as the lower boundary, the first wavelength is generated when the laser operates at a first temperature of an ambient and the second wavelength is generated when the laser operates at a predetermined temperature higher than a second temperature of the ambient, the first temperature is higher than the second temperature, and the first wavelength is shorter than a long wavelength that is generated by a laser centered on the specific wavelength that operates at the first temperature;
• measuring a temperature of the ambient of the laser;
• comparing the measured temperature to a first preset temperature;
• turning on a heater provided in a vicinity of the laser when the measured temperature is lower than the first preset temperature, the heater heating the laser such that a wavelength in the controlled wavelength range that is generated by the laser when heated by the heater from the second temperature is longer than a short wavelength that is generated by the laser centered on the specific wavelength that operates at the second temperature;
• measuring the temperature of the ambient with the heater on;
• and
• turning off the heater when the measured temperature with the heater on is higher than a second preset temperature.

A computer program product storing instructions for execution on a computer system to stabilize a wavelength of a laser, which when executed by the computer system, causes the computer system to perform:

• instructions for generating a predetermined wavelength when a laser operates at room temperature, the predetermined wavelength being offset from a specific wavelength, the laser has a controlled wavelength range, the wavelength range having a first wavelength as the upper boundary and a second wavelength as the lower boundary, the first wavelength is generated when the laser operates at a first temperature of an ambient and the second wavelength is generated when the laser operates at a predetermined temperature higher than a second temperature of the ambient, the first temperature is higher than the second temperature, and the first wavelength is shorter than a long wavelength that is generated by a laser centered on the specific wavelength that operates at the first temperature;
• instructions for measuring a temperature of the ambient of the laser;
• instructions for comparing the measured temperature to a first preset temperature;
• instructions for turning on a heater provided in a vicinity of the laser when the measured temperature is lower than the first preset temperature, the heater heating the laser such that a wavelength in the controlled wavelength range that is generated by the laser when heated by the heater from the second temperature is longer than a short wavelength that is generated by the laser centered on the specific wavelength that operates at the second temperature;
• instructions for measuring the temperature of the ambient with the heater on;
• and
• instructions for turning off the heater when the measured temperature with the heater on is higher than a second preset temperature.