A folded Cassegrain telescope saves up space and a whole world of troubles

A folded Cassegrain type telescope objective is nothing new, but given present advancements in optical manufacturing, a worth reconsidering.

Cutting the optical tube length in half with a flat mirror and moving the secondary to the center of primary mirror hole is not a new idea and does nothing to help manufacture and assembly. Instead making a single mirror with a binary surface, i.e. one radius at inner zone and another in outer zone, a whole world of manufacture and assembly problems can be avoided. Assembly problems would eliminate themselves, and manufacturing would get easier by making traditional manufacturing near impossible and forcing more advanced techniques.

Published 30.10.2016 by Jani Achrén, who explains more here.

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Fast F/1 reflective Maksutov microscope objective

20150206_2Originally suggested by Maksutov, a Maksutov microscope objective (or eyepiece) is a reverse Gregorian type reflective objective. It has high numerical aperture and has corrected spherical, coma and color aberrations. It requires a field flattener to correct the field curvature, but for on-axis observations, it has a long working distance and short total track.

Originally published 6.2.2015 by Jani Achrén. Read the rest from here.

Ways to trip by using stock optical components

20141107_1Stock optical components are very attractive option for a developer. You get parts ASAP, keep prototyping costs down and one gets fitting optomechanical parts to go, and you can do all by yourself as well. Then again, there are whole factories spewing out same parts to your competitor, with same instructions and howto’s. So it comes down to this: what SPECIAL can you do with stock optical parts? Turns out, quite a lot. However, they might need an optical engineer to pull them off. I’ll go through some examples of common tripping points of stock optical components, and a short description on how an optical designer can overcome them.

Published 7.11.2014 by Jani Achrén, and he invites you to read the rest here.

Building an optical system with stock optics

Several manufacturers can provide pre-fabricated optical parts for very reasonable prices. For a customer they are very attractive, but for the designer they are that sinister oppressive path through a damp dark forest after reading Lovecraft novels – how can anything innovative come out of something as coarse as pre-fabricated parts? Client is demanding the impossible! Or when viewed with a positive attitude, just kicking you forward. Pre-fabricated components design is very attractive and here to stay, so best to make the best of it. Here I design some basic finite conjugate objectives with pre-fabricated parts and see their limitations first-hand.

Originally published 15.5.2014 by Jani Achrén.