Re: [ATM] Bench star test

["Vladimir Galogaza" <vladimir.galogaza1@zg.t-com.hr>]

Dale,

> Laser diode's without their lens make a very good point source.

I have my doubts about this.

If a "point source" (an oxymoron in itself) is a source that has
small physical size. than laser diode is really small source (few microns).

If "point source" is considered to be good approximation for
source of spherical wavefront than, I  think,
laser diode (lensless) has lot of aberrations in spite of its small size.
Astigmatism, for example.

I have used it in Foucault tester and had problems. I will try spatial
filtering to see if this  can improve on wavefront sphericity and thus
verify my assumption.
But  required spatial filter is not a trivial thing to construct, at least 
for me.

Regards
Vladimir.



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