NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Galilean eyepiece description?
From: Peter Monta
Date: 2021 Apr 23, 19:25 -0400
From: Peter Monta
Date: 2021 Apr 23, 19:25 -0400
Hi Paul,
I am certain that someone posted a pdf of description of the function of a Galilean eyepiece and its design here - and likely more than once! But try as I might, I can't find the document. Thus, hoping someone can help!
The Wikipedia page for "refracting telescope" has a ray diagram for a Galilean telescope if that's of any help. For the design of the eyepiece specifically, I don't know of much design guidance beyond making it an achromat (if the objective is achromatic, which was not the case for the early telescopes). Barlow lenses (or "teleconverters" in photography lingo) are similar to Galilean eyepieces, and they're probably carefully computer-designed these days for their application cases, although they're much less complex than a multi-group lens.
Cheers,
Peter
