Previously I have discussed an automated optimization method for designing a fast four lens refrative objective that uses symmetrically manufactured lenses (you can catch up about it from this downloadable pdf). The original development model used glass from Schott, but next I will discuss how it won’t make much difference which glass manufacturer one uses.
Parameters are nice. They make a goal that is much easier to reach than an invisible one. Optical designer knows what parameters would be nice to know, but asking them from client who might be the idea man or organizer, might not know what they might be. Then it’s up to the optical designer to ask the right questions in order to know the needed parameters the client does not know.
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.
A two-slit interferometric wavefront error measuring technique combines high sensitivity and low-cost components.
Testing of conical surfaces for mirrors or lenses most often require interferometry and with it, expensive devices to detect wavefront aberrations.
A two-slit Interferometric wavefront error measuring technique, first deviced by Yrjö Väisälä of Tuorla Observatory, combines high sensitivity (much higher than with traditional Foucault or Ronchi tests) with few layout components most probably already in posession of ATM mirror manufacturers. The principles of this test have been developed into an interferometric Hartmann test.
Originally published 14.2.2013. You can read more about it here.