Calibration of laser systems
View Patent ↗A method for determining a condition of the laser system includes determining a change in a laser current from a preset value. The method includes determining the preset value based on a temperature signal and a supply voltage signal for the laser. The preset value can be determined from a table or from a function.
1. A method for laser system to determine a condition of the laser system, comprising:
generating a temperature signal corresponding to a temperature of a laser;
generating a supply voltage signal corresponding to a supply voltage to the laser system;
determining a present value of a current to the laser;
determining a preset value of the current based on the temperature signal and the supply voltage signal; and
determining a change in the current, wherein the change in the current indicates the condition.
2. The method of claim 1 , wherein said determining a preset value of the current comprises using a relationship of values of the current, the temperature signal, and the supply voltage signal in a memory, the relationship is stored in a manner selected from the group consisting of a table and a function.
3. The method of claim 1 , wherein said determining a change in the current comprises a step selected from the group consisting of calculating a difference between the present value and the preset value of the current, and calculating a ratio between the present value and the initial value of the current.
4. The method of claim 1 , wherein said determining a present value of a current comprises adjusting the present value of the current according to a difference between a reference signal and a feedback signal proportional to an output power of the laser.
5. The method of claim 1 , wherein the condition is selected from the group consisting of a degradation of the laser system and a malfunction of the laser system.
6. The method of claim 1 , further comprising outputting the change in the current to a host.
7. A laser system, comprising:
a memory, the memory storing a relationship between a plurality of preset values of a current to a laser for a first plurality of values of a temperature signal and a second plurality of values of a supply voltage signal, the supply voltage signal corresponding to a supply voltage to the laser system;
a controller, the controller being coupled to receive (1) the temperature signal, (2) the supply voltage signal, (3) a preset value of the current from the memory based on the temperature signal and the supply voltage signal, the controller being programmed to determine a change in the current.
8. The laser system of claim 7 , wherein the relationship is stored in a manner selected from the group consisting of a table and a function.