Zoltan,

to me it sounds more like a problem with overheating. The system I was 
working with had quite similar troubles, and it turned out that the 
laser itself was getting to hot and switched off at some point. There is 
a temperature security switch close to the Argon laser. To evaluate 
this, try stepwise laser-power measurements from 0 to 100% laser power 
(AOTF at 100%). In my case power increased until 50% and then dropped 
slightly towards 100% - clear sign for overheating.

Another candidate might be related to the AOTF, if the temperature 
control of this one fails it could also switch on and off due to 
overheating. But then the problems would also appear with other visible 
lines not coming from the Argon.

Michael


Zoltan Cseresnyes wrote:
> Dear List Members,
> 
> We have a fairly new Leica SP5 system (15 months old) that has a Lasos 
> multi-line argon laser, part number LGK 7872 ML05, which now has failed 
> for the second time within a year.  The error appears if we turn the 
> total power slider to 30% or more, in which case the laser starts to 
> "stutter" (i.e. cuts out randomly during scanning) that produces 
> randomly distributed blank lines and bands in the acquired image.  If we 
> then move the power slider back to below 30%, the laser performance 
> returns to normal. Upon the first appearance of this error, Leica simply 
> replaced the head and the power supply, but now the same error appeared 
> again, making us more than suspicious that this is a common form of 
> failure for this laser in the Leica system.
>   Did anyone experience the same or similar problem?  If so, how did you 
> resolve it?  Was it laser specific, manufacturer related or Leica related?
>   Any information will be much appreciated!  Thank you very much,
>  
> Zoltan
> 
> --
> Zoltan Cseresnyes
> Facility Manager, Imaging Suite
> Department of Zoology, University of Cambridge
> Downing Street Cambridge CB2 3EJ
> United Kingdom