http://confocal-microscopy-list.275.s1.nabble.com/Reporting-laser-power-in-publication-tp7584120p7584132.html
Thanks all for your helpful suggestions. For the purposes of this
range of mW/micron2 values. If the user does require greater precision and
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>
> Hi Ian, I actually helped design the low-power version of that power meter
> head with Pina Colarusso. The S175C is for higher-power applications, while
> the original S170C is for lower power. The 170 is more accurate for sub-mW
> powers typical of confocal systems. The higher-power one is good for power
> for certain non-linear processes. Both the 175 and 170 are oil and water
> compatible, and I found using the proper immersion medium on the sensor was
> especially critical for oil lenses.
>
> Craig Brideau
>
> On Tue, Aug 18, 2015 at 3:38 AM, Ian Dobbie <
[hidden email]>
> wrote:
>
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http://www.imgur.com and include the link in your
> posting.
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> >
> > Johannes Helm <
[hidden email]> writes:
> >
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> > > To join, leave or search the confocal microscopy listserv, go to:
> > >
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> > posting.
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> > >
> > > Dear Jolien,
> > >
> > > it is not an easy task to measure the power in the focal region of the
> > > objective "exactly" and the job gets even more complicated if you want
> > > to determine the power "per pixel" in the way you describe.
> > >
> > > 1)
> > > In general:
> > >
> > > a)
> > > Unless you have a dry objective, some power will, even - and
> > > particularly - in case of "perfect" or "quasi perfect" alignment - be
> > > "lost" when measuring the laser power with the detector placed under
> > > the objective because of total reflection (unless you could "immerse"
> > > the sensitive area of the power meter in the immersion medium, which
> > > most probably would be bad for the power meter). In other words: If
> > > you have an oil immersion objective and do not have any oil on its
> > > front lens, the "outer ring" of light incident from the inside of the
> > > objective to the front lens will be lost due to total reflection (will
> > > be "sent back into the objective").
> >
> > Thorlabs have a nice new power meter head.
> >
> >
http://www.thorlabs.de/thorproduct.cfm?partnumber=S175C> >
> > It is in a slide form factor with a glass coverslip and then a
> > scattering index matched media before the sensor itself. This should
> > give you accurate readings even with a oil immersion objective. No use
> > for a 1.6 NA TIRF objective but good for normal oil objectives.
> >
> > Ian
> >
>