David,  We get our holographic notch filters from Kaiser Optical systems Inc. 371
Parland Plaza, PO Box 983, ann Arbor, MI 48106 313 665-8033. They have similar
sensitivity to angle of incidencs as do interference filters, but I cannot answer
any of \your other questions except we have single line ones  and have been using
them without degradation for several years.

Jim

[log in to unmask] wrote:

> Could you suggest a good source for holographic notch filters?  Are they
> available off-the-shelf, or only as custom orders?  Personally, I have been
> chasing Rugate filters as a high throughput solution, but have struggled to
> find a vendor who can make them.  After a few years of trying, we still
> haven't got a good multiline notch into our instruments.  Do holographic
> filters come in three and four notch combinations?  How robust are they, i.e.
> how sensitive to mechanical damage, incident angle, temperature, humidity,
> power density?
>
> Thanks in advance,
>
> David Carter
> oQQQQQ@
>
> In a message dated 11/1/99 9:03:09 AM, [log in to unmask] writes:
>
> << The best but most expensive solution is holographic notch filters. They
> have
> very strong, up to 6 orders of magnitude attenuation of the laser line, with
> 75-85% transmission of all other wavelentghs. They are really nice and pass
> all
> the emitted signal as they don't even attenuate the tails of the specta. The
> cost about $1500 each. However when you improve the front end signal being
> measured by a $100,000+ instrument you have to ask yourself if it is worth it.
> Obviously we do.
>
> Jim Turner
>
> Milton Charlton wrote:
>
> > Is there any consensus on which manufacturer's emission filters have the
> > highest transmittance?  I want to replace emission filters on our Biorad
> > 600.  Has anyone noticed any improvement when emission filters were
> replaced?
> >  I have also noticed that the 488nm excitation filter looks burnt at
> > a particular viewing angle.  Replacing this gave a little more light but
> > we always use the densest ND filter for excitation anyway so this did not
> > help much.
> > Thanks
> > Milton Charlton >>