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

Posted by Emmanuel Levy 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-tp7587264p7587266.html

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Dear Peter,

Thank you for this information.

Are you running your lasers at full power?


Yes we are.


> What combiner are you using?


It is a custom made combiner, from the company that assembled the
microscope.


> 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.
>

Thanks a lot for this info, I'll discuss it with the company.

If there are other opinions, in particular regarding the loss between te
fiber-output and the objective, I'd be glad to hear them.

Best wishes,

Emmanuel





>
> I hope this helps.
>
>
> Kind Regards
>
> Pete Brunt
>