Re: 405 laser intensity at the objective is 0.15% of actually intensity ... is this normal?

Posted by Peter Brunt AVR on
URL: http://confocal-microscopy-list.275.s1.nabble.com/405-laser-intensity-at-the-objective-is-0-15-of-actually-intensity-is-this-normal-tp7587264p7587265.html

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Hi Emmanuel
Are you running your lasers at full power?  What combiner are you using?  I can't comment so much on the power you have at your objective but on your combiner side the values look low.  Going into a multi-mode fibre should be like a barn door for your lasers so if we imagine a ~5% (x2) loss due to combining optics and an ~80% coupling efficiency, you should still be getting a ~72% average coupling efficiency into the fibre.  It sounds to me like the setup may need to be realigned. If you still don't see an improvement then one other possibility is that the 405nm laser has degraded your fibre due to solarisation and the fibre needs replacing.  

I hope this helps.


Kind Regards

Pete Brunt