http://confocal-microscopy-list.275.s1.nabble.com/Re-SHG-tp592071p592073.html
> Search the CONFOCAL archive at
>
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal I've interspersed a
> few of my own comments below:
>
> >
> > You have to make sure you carefully filter the remaining of the Ti:Sa
> laser after doubling, so you won't have 2P events
> > as well.
>
> Typically a good short pass filter centered at 600 or 650 will do the job.
> Keep it at right-angles to the beam.
>
> >
> > If the doubling crystal is your own "home built" addition, you don't place
> it in the Ti:Sa cavity but rather after it.
> >
>
> Yeah, a doubling crystal in the cavity will potentially wreck the laser if
> it's not built for it.
>
> > I guess you're using a BBO or LBO, in which case a 5mm by 5mm
> > piece will be enough, coming to it at a tight focus.
>
> Typically you get a very thin slip of crystal, almost like a microscope
> cover slip. Normally this comes mounted in a 1" metal circle or some
> 'frame' that you can place in an optical mount.
>
> >
> > Finding the "mismatch" axis and aligning it is a bit tricky and requires 6
> degrees of freedom (x-y-z rotational and angular).
>
> If you have a 1/2 waveplate to rotate the polarization of your laser it
> takes one degree of freedom out of the equation (or that is to say transfers
> it to the waveplate, which is simple to rotate). In the case of the
> waveplate you want to rotate it around the optical axis. That is to say
> pretend your laser beam is an axle and the waveplate is a wheel rotating
> around it. Adjust the polarization of your laser beam such that it is
> perpendicular to the table surface. If you are very lucky your laser might
> already be this way naturally. This means you might be able to get away
> without the waveplate. The crystal, on the other hand, you want to first
> align so that it's preferred polarization is the same as the laser, i.e.
> perpendicular to the table if that's the laser's polarization (or you made
> it that way with the waveplate). Usually there's a mark for this on the
> crystal mount/frame. You then want to turn the crystal on an axis which is
> also perpendicular to the table. Thorlabs and Newport both carry
> appropriate mounts for doing this sort of thing. Again, the crystal
> manufacturers, or even the technical support guys at Thor or Newport, can
> generally help you out. Once you get SHG just gently play with all the
> degrees of freedom until you get a maximum. Measure the power after the
> short pass filter and seek the highest value.
>
> Craig
>
>
>
> >
> >
> >
> > Hope this helped- good luck,
> >
> > Eli
> >
> >
> > 6 degreess
> >
> >
> >
> >
> >
> > ---- Original message ----
> > >Date: Thu, 8 May 2008 09:34:58 +0800
> > >From: Peng Xi <
[hidden email]>
> > >Subject: Re: SHG
> > >To:
[hidden email]
> > >
> > >Search the CONFOCAL archive at
> > >
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal> > >
> > >Hi Sarah,
> > > Just like you asked, it will be an one-photon excitation. So,
> > >although it is possible that you create a femtosecond 400nm laser pulse,
> > >it is still linear excitation -- one photon process. Thank you!
> > > I am very interested in the experiment itself -- have you tried to
> > >put a SHG crystal inside the Ti:Sa laser cavity and see the 400nm
> emission?
> > >
> > >Best regards,
> > >Peng Xi
> > >Associate Professor
> > >Institute for Laser Medicine and Biophotonics
> > >Shanghai Jiao Tong University
> > >800 Dongchuan Rd.
> > >Shanghai 200240, China
> > >Tel: (86) 21-3420-4076
> > >
http://biophotonics.sjtu.edu.cn/> > >
> > >
> > >
> > >Sarah Kefayati wrote:
> > >> Search the CONFOCAL archive at
> > >>
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal> > >> Hello all,
> > >>
> > >> I appreciate if you could help me with my question:
> > >>
> > >> I just want to make sure about this fact that by using a non-linear
> > >> crystal in the path of my Ti-sapphire laser I will have the frequency
> > >> doubled beam which excites my sample via traditional one-photon
> > >> excitation.
> > >> But dose the intensity of the emitted fluorescence depend on
> > >> excitation power linearly or quadratically?
> > >>
> > >> any information in this regard is highly appreciated.
> > >>
> > >> Thanks
> > >> Sarah
> > ________________________________
> > Eli Rothenberg, Ph.D.
> > Post Doctoral Research Associate,
> > Howard Hughes Medical Institute,
> > Department of Physics,
> > University of Illinois,
> > Urbana-Champaign. 61801.
> > Illinois, USA
> > Tel: +217-333-3393;
> > Fax: +217-244-7187;
> > Email:
[hidden email]
> >
>
>