Patent ID: 8831053

Claim:
A method for monitoring a laser system comprising a plurality of laser modules connected in series, there being connected in parallel to each laser module a bypass arrangement for bridging the corresponding laser module, the method comprising: a. determining a first laser power of the laser system with two or more laser modules of the plurality of laser modules operational; b. activating the bypass arrangement of at least one operational laser module so that at least one of the operational laser modules is bypassed; c. determining a second laser power of the laser system with the at least one operational laser module bypassed; d. monitoring the laser system based on a variation between the first and second laser powers, wherein monitoring the laser system comprises determining a degradation and/or efficiency of the at least one bypassed laser module based on the variation between the first and second laser powers; and e. deactivating the activated bypass arrangement of the at least one bypassed laser module to switch the at least one bypassed laser module back on.