*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
*****
Hi, yes you are thinking about it correctly. The "beam dump" will be your second system.
We are using AOMs from Carl Zeiss. The AOMs are controlled from the Zeiss operating software so that you can easily adjust power in the software.
An alternative method is using a Pockel's Cell to adjust percent power (you would need 2). There are different sources for Pockel's Cells, Thorlabs etc. *They are lambda specific so make sure to match the lambda range you wish to use.
Best wishes,
Brian D Armstrong PhD
Assistant Research Professor
Director, Light Microscopy Core
Beckman Research Institute
City of Hope
Dept of Neuroscience
1450 E Duarte Rd
Duarte, CA 91010
626-256-4673 x62872
http://www.cityofhope.org/research/support/Light-Microscopy-Digital-Imaging/Pages/default.aspx
-----Original Message-----
From: Confocal Microscopy List [mailto:[log in to unmask]] On Behalf Of yuansheng sun
Sent: Tuesday, January 29, 2013 1:57 PM
To: [log in to unmask]
Subject: Re: A question about splitting a TiSa laser beam and controlling its power
*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
*****
Thank you all so much for the great suggestions. Following the
suggested direction, I searched and found an application note from Newport
(no competing interest). There are two beams out of the Glan-Laser prism -
one is the main beam output and the other is called the beam dump. I am
wondering if I can achieve any split between the main output and the dump
by varying the degree of the half wave plate. I assume the sum of the main
output power and the dump power is close to the Ti:Sa laser power (~1.3 W
for our system at 800 nm).
Brian, can you share your AOM information? Thanks.
Sheng
On Tue, Jan 29, 2013 at 4:36 PM, Armstrong, Brian <[log in to unmask]>wrote:
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> Hi, yes, and for a rotation mount we used: Newport RSP-IT (
> http://www.newport.com/Optic-Rotation-Mounts/177122/1033/info.aspx) [no
> competing interest].
> We can adjust the percent power sent to each microscope this way. (The
> beam then goes through an AOM which adjusts the percent remaining power to
> the microscope, [so we have two AOMs]).
>
> Cheers,
>
> Brian D Armstrong PhD
> Assistant Research Professor
> Director, Light Microscopy Core
> Beckman Research Institute
> City of Hope
> Dept of Neuroscience
> 1450 E Duarte Rd
> Duarte, CA 91010
> 626-256-4673 x62872
>
>
> http://www.cityofhope.org/research/support/Light-Microscopy-Digital-Imaging/Pages/default.aspx
>
>
> -----Original Message-----
> From: Confocal Microscopy List [mailto:[log in to unmask]]
> On Behalf Of Craig Brideau
> Sent: Tuesday, January 29, 2013 1:19 PM
> To: [log in to unmask]
> Subject: Re: A question about splitting a TiSa laser beam and controlling
> its power
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> As Johannes says, you need optomechanics to rotate the waveplate. You can
> either use a manual rotation mount (you don't need very fine control, so a
> thumb-wheel is fine), or if you are adverse to sticking your hand anywhere
> near the beam you can use a motorized mount. In systems with other safety
> mechanisms, (i.e. laser blocks and such) I have used manual mounts. In
> situations where it will be used by inexperienced users I tend to motorize
> things to keep untrained hands away from the laser and optics.
>
> Craig
>
>
> On Tue, Jan 29, 2013 at 2:05 PM, Johannes Helm <[log in to unmask]
> >wrote:
>
> > *****
> > To join, leave or search the confocal microscopy listserv, go to:
> > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> > *****
> >
> > Good evening,
> >
> > Craig has already provided the answer, see below.
> >
> > I just would like to mention in addition that one can buy lambda/2
> plates,
> > which show the lambda/2 effect with minor deviations, only, i.e.: are
> > achromatic, over the entire wavelength range of the usual approx. 680nm -
> > approx. 1060nm Ti:Sap lasers common in non linear laser scanning
> > microscopy (and have AR coatings for that entire wavelength range). They
> > are possibly somewhat more expensive than lambda/2 plates but may
> > nevertheless be the item of choice. I do not have ANY commercial
> > affiliations and, hence, allow myself to mention that I personally have
> > experienced that the achromatic lambda/2 plates from Halle are excellent
> > units for the purpose, www.b-halle.de .
> >
> > Of course, one also will need a suitable polarization beam splitter and
> > the opto mechanics to position and adjust both, the lambda/2 plate and
> the
> > polarization beam splitter in the appropriate way. Glan prisms, as Craig
> > mentioned, will be excellent for the purpose but they usually will emit
> > not one but one main and one minor deflected beam under an angle
> different
> > from 90 degrees, while conventional polarization beam splitters will emit
> > the deflected beam at roughly 90 degrees. Also, check out before buying
> > any beam splitter about potential "un-flatnesses" on the lateral surfaces
> > of the Glan prism or Polarization beam splitter. A Foster prism might
> also
> > be a good item if you want one beam to continue straight forward and the
> > other to continue at 45 degrees or so.
> >
> >
> >
> > Also, if you want to install that lambda/2 plate on an optical table with
> > a lot of other elements like EOMs, photodiodes, spatial filters, beam
> > expanders and the like and if all will be "hidden" behind a metal curtain
> > to protect laser radiation from becoming dangerous in the lab, then you
> > should consider to install the lambda/2 plate in a motor driven rotator,
> > which you can control from a PC.
> >
> > Best wishes,
> >
> > Johannes
> >
> >
> > > *****
> > > To join, leave or search the confocal microscopy listserv, go to:
> > > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> > > *****
> > >
> > > A Glan-Laser prism and half-waveplate (NIR Achromatic) will work. The
> > > prism splits the laser into two beams, with the amount of power going
> > into
> > > each beam governed by the angle of the waveplate. Note you may need
> > > another waveplate to rotate the polarization of one of the beams back
> > into
> > > your microscope.
> > >
> > > Craig
> > >
> > >
> > > On Tue, Jan 29, 2013 at 11:41 AM, yuansheng sun
> > > <[log in to unmask]>wrote:
> > >
> > >> *****
> > >> To join, leave or search the confocal microscopy listserv, go to:
> > >> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> > >> *****
> > >>
> > >> Dear Listers,
> > >>
> > >> I want to split the laser beam from a TiSa laser (700~1000 nm, 1.3W at
> > >> 800
> > >> nm). I know some people did this way to feed one TiSa laser to two
> > >> microscopes. I am wondering if I can get a simple beam splitter for
> > >> this
> > >> purpose. And also, what would be the simple (and reliable) device you
> > >> would suggest to control the TiSa laser power? Thanks a lot in
> advance
> > >> for
> > >> any suggestion.
> > >>
> > >> Best regards,
> > >> Yuansheng Sun,
> > >> Keck Center for Cellular Imaging
> > >> University of Virginia
> > >>
> > >
> >
> >
> > --
> > P. Johannes Helm
> >
> > Voice: (+47) 228 51159 (office)
> > Fax: (+47) 228 51499 (office)
> >
>
>
> ---------------------------------------------------------------------
> *SECURITY/CONFIDENTIALITY WARNING:
> This message and any attachments are intended solely for the individual or
> entity to which they are addressed. This communication may contain
> information that is privileged, confidential, or exempt from disclosure
> under applicable law (e.g., personal health information, research data,
> financial information). Because this e-mail has been sent without
> encryption, individuals other than the intended recipient may be able to
> view the information, forward it to others or tamper with the information
> without the knowledge or consent of the sender. If you are not the intended
> recipient, or the employee or person responsible for delivering the message
> to the intended recipient, any dissemination, distribution or copying of
> the communication is strictly prohibited. If you received the communication
> in error, please notify the sender immediately by replying to this message
> and deleting the message and any accompanying files from your system. If,
> due to the security risks, you do not wish to receive further
> communications via e-mail, please reply to this message and inform the
> sender that you do not wish to receive further e-mail from the sender.
> (fpc5p)
> ---------------------------------------------------------------------
>
|
