Re: DIY phase contrast annulus

Posted by JOEL B. SHEFFIELD on
URL: http://confocal-microscopy-list.275.s1.nabble.com/DIY-phase-contrast-annulus-tp7584253p7584256.html

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We have made Hoffman condensers using aluminum foil.  I see no reason that
you couldn't do something similar, using the mask that you have generated,
to carefully cut out the ring in a sheet of aluminum that is already tacked
down to a piece of glass.

Joel



Joel B. Sheffield, Ph.D
Department of Biology
Temple University
Philadelphia, PA 19122
Voice: 215 204 8839
e-mail: [hidden email]
URL:  *http://tinyurl.com/khbouft <http://tinyurl.com/khbouft>*

On Mon, Sep 28, 2015 at 8:56 PM, Rusty Nicovich <[hidden email]>
wrote:

> *****
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> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Ben,
>
> You could use chemical etching to reproduce your printed annulus on a piece
> of copper or brass.  Electronics DIYers make PC boards by laser printing a
> pattern onto glossy paper, using an iron to transfer the toner to a piece
> of copper-clad PC board, and the ferric chloride to etch away the copper.
> Same principle will work on brass.  Takes some trial and error and a few
> nasty chemicals, but is a great way to get high-resolution parts out of
> sheet metal.
>
> Another option is to have the annulus laser-cut.  Shouldn't cost more than
> $20 for something annulus-sized.  Usually you need to supply the operator
> with an Adobe Illustrator or other vector drawing format but you already
> have the drawing.  The cutter here is run by the architecture design school
> and their cutter has a resolution of ~300 microns.  Should be able to get
> stainless steel or even powder-coated aluminum cut without too much
> hassle.  This would be my preference since it requires less OH&S work on my
> part.
>
> Rusty
>
> On Tue, Sep 29, 2015 at 9:53 AM, Smith, Benjamin E. <[hidden email]
> >
> wrote:
>
> > *****
> > To join, leave or search the confocal microscopy listserv, go to:
> > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> > Post images on http://www.imgur.com and include the link in your
> posting.
> > *****
> >
> > Hey Microscopists,
> >     A lab here has a nice phase objective but no annulus, so I decided to
> > see if I could make one for them.  I measured the phase plate diameter at
> > the focal plane, and printed out an annulus that lined-up perfectly.
> > However, too much light gets through the ink to be of much use, so I was
> > wondering if anyone had experience with an easy way to make a fully
> opaque
> > annulus.
> >
> > Cheers,
> >    Ben Smith
> >
> > Benjamin E. Smith, Ph.D.
> > Samuel Roberts Noble Microscopy Laboratory
> > Research Scientist, Confocal Facility Manager
> > University of Oklahoma
> > Norman, OK 73019
> > E-mail: [hidden email]
> > Voice   405-325-4391
> > FAX  405-325-7619
> > http://www.microscopy.ou.edu/
>