METHOD FOR CONTROLING WAVELENGTH TUNABLE LASER, AND WAVELENGTH TUNABLE LASER

摘要

A lasing wavelength is controlled so that a wavelength detection result becomes a first target value; selection is made to select either a step of calculating a second target value as a wavelength detection result with a shift of the lasing wavelength, or a step of calculating a third control value of a wavelength characteristic of an etalon for letting a laser lase at a wavelength with a shift of the lasing wavelength; in the former step, the lasing wavelength is controlled so that the wavelength detection result becomes the second target value; in the latter step, the lasing wavelength is controlled so that the wavelength detection result becomes the first target value.

主权项

1. A method for controlling a wavelength tunable laser having a wavelength detection unit including an etalon, the method comprising:
a first step of acquiring information of a first control value to define a wavelength characteristic of the etalon in the drive condition corresponding to a first wavelength, a first target value of the wavelength detection unit corresponding to the first wavelength, a value of a second wavelength different from the first wavelength, and a value of a shift amount; a second step of calculating a second control value from the first control value to define a wavelength characteristic of the etalon to acquire the second wavelength when the wavelength detection unit detects the first target value; a third step of selecting either A) shifting wavelength of the laser by changing the first target value to a second target value corresponding to the shift amount, or B) shifting wavelength of the laser by changing the second control value of the wavelength characteristics of the etalon to a third control value of the wavelength characteristics of the etalon corresponding to the shift amount; and a fourth step of driving the laser by using either A) second control value of the wavelength characteristics of the etalon, and the second target value, or B) third control value of the wavelength characteristics of the etalon, and the first target value.