Re: Query: Longer working distance objectives?

From: Kevin Cunningham (smskjd_at_mindspring.com)
Date: 06/28/04 

Date: Mon, 28 Jun 2004 18:35:50 GMT

"Charlie+" <charlie@xxx.net> wrote in message
news:tbi0e09cjb5ejh1m0lbjt4amd49s5mrn5h@4ax.com...
> I wonder if any experts out there know if there are longer working
> distance objectives that were produced for 160mm tubelength
> microscopes in the 20x and 40x powers? And if so what I should look
> out for on Ebay etc in the way of makes and specific markings on the
> objectives.
> Presumably NA figure would be a tradeoff of some description on this
> type of lens? I also presume there is no work-around to get longer
> distance to subject from a standard 160 / - objective!?
> - TIA
> Charlie+

There are quite a number of long working distance objectives. Most are for
semi-conductor instruments so some of them are not 160mm. Your description
of a "160/-" is mostly correct, semi-conductor objectives don't use cover
glass. There are a few biological objectives. The big advantage is that
everybody is using infinity correction so there is less of a market for
160mm objectives.

Kevin

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  • Query: Longer working distance objectives?
    ... I wonder if any experts out there know if there are longer working ... distance objectives that were produced for 160mm tubelength ... microscopes in the 20x and 40x powers? ...
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  • Re: Query: Longer working distance objectives?
    ... Such objectives were made by Olympus for the older 160 tube length Olympus ... objectives and standing for ultra-long working distance. ... > I wonder if any experts out there know if there are longer working ...
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