Laser light generator control circuit and laser light generator control method

摘要

The laser light generator control circuit comprises a load section, a control section, a bias current circuit section, and a modulation current circuit section. The load section generates a monitor voltage V₁ that corresponds to the optical current corresponding to the amount of light received by a monitor light receiving element for receiving light from the laser light generator. The control section selects a combination (Db, Dm) in accordance with the result of comparing a value corresponding to the monitor voltage V₁, and a reference value, from a group of combinations (Db, Dm)_n that comprises a plurality of combinations (Db, Dm) of a value Db that corresponds to the bias current and a value Dm that corresponds to the modulation current, these combinations being specified so that the light emission power and the extinction ratio are constant, and generates a first control signal V₂ and a second control signal V₃ on the basis of the selected combination (Db, Dm).