Verfahren und Vorrichtung zur Steuerung eines Halbleiterlasers

A method and apparatus for driving a semiconductor laser device (SLD1) in a laser recorder to produce a substantially constant optical power output over a range of temperatures while preserving a high optical switching frequency. A semiconductor laser device (SLD1) and a current sink (SLD2) are used in combination in driver circuit. A bias current (Ib1) maintains the semiconductor laser device (SLD1) at a first operating state, below a selected optical power threshold, and another bias current (Ib2) maintains the current sink (SLD2) at a first state also below a selected threshold. An information current (Im) is added to the bias current (Ib1) to drive the semiconductor laser device (SLD1) at a second state having a higher optical power. The information current (Im) is then steered to the current sink (SLD2), adding to the other bias current (Ib2), to drive the current sink (SLD2) at a second state such that the semiconductor laser device (SLD2) returns to the first state. A feedback signal (E1) adjusts the information current (Im) according to the output power of the semiconductor laser device (SLD1) when operating at the second state and according to the conditions of the current sink (SLD2).