B. H. Walter's paper on "Specifying the visual optical system" (1 Viewer)

[Kevin Purcell]

An interesting paper at the UA optomech site (for their optomech course)

B. H. Walter's paper on "Specifying the visual optical systems" from 1979.

It uses a folded light path telescope (interesting in itself) as an example of how to specify an optical system hitting all the interesting parameters.

If you are interested in reviewing (or just understanding) optics it makes an interesting read to see what parameters you should be interested in. What sort of tolerances should you expect for different parameters?

There is even a nice piece on "what is the resolution of the eye" (and how to turn it into something measurable!). A sense of deja vu for people reading the forums here, perhaps, even though he comes up with a

There is also a nice section on off-axis image quality.

A fairly easy read even if you don't have a optics or even a science background.

http://www.optics.arizona.edu/optom...psis/2008/paper/Walker 1979_for Jeff wang.pdf

A student synopsis is provided too (in a less friendly format)

http://www.optics.arizona.edu/optom... on Specifying the Visual Optical System.docx

.docx is a Microsoft Office 2007 format. There are free convertors out there.

 

[elkcub]

It's a good paper. Bruce Walker is a well-known author. Optical Engineering Fundamentals (1995) is a modern classic in the McGraw-Hill series. Optical Design for Visual Systems (2000) is a fairly easy to read SPIE Press soft cover (but not inexpensive), and he also contributed Chapter 7 "Lens Design Examples for Visual Applications" in Visual Instrumentation (1999) by Pantazis Mouroulis. He is characteristically "practical" in how he explains things; unfortunately, too often he leaves it to the reader to figure out a general formulation. (Just my opinion). I believe he studied under the master, Warren J. Smith.

Of the papers listed on the Arizona site there is one by Konrad Seil (1991), Swarovski Optik, entitled "Progress in binocular design," which is well worth reading. http://www.optics.arizona.edu/optomech/papers/Seil 1991.pdf
In particular it addresses the problems associated with prism coatings on Schmidt/Pechan systems. I posted the article on BF a few years ago, but there was little interest. It's a real gem.

Another grabber is "Optical design and engineering: lessons learned" by Pantazis Mouroulis, http://www.optics.arizona.edu/optomech/papers/mouroulis 2005.pdf.

That Arizona site is a collection of the best of the best, and I'd recommend that folks download anything relevant to binoculars before it disappears like BVD and Alula.

Ed

 

[Kevin Purcell]

Thanks for those comments, elkcub

Of the papers listed on the Arizona site there is one by Konrad Seil (1991), Swarovski Optik, entitled "Progress in binocular design," which is well worth reading. http://www.optics.arizona.edu/optomech/papers/Seil 1991.pdf
In particular it addresses the problems associated with prism coatings on Schmidt/Pechan systems. I posted the article on BF a few years ago, but there was little interest. It's a real gem.

I posted the article here too in Sept 2008 and there was a fair bit of interest!

See this thread

http://www.birdforum.net/showthread.php?t=122141

I have a couple of other papers I'll post links too and try to start a discussion.

 

[ronh]

Thanks Kevin for that reference, and also Ed, for Mouroulis's paper. Both raised my conciousness of the many tradeoffs in optical design. In fact, both made me feel so sorry for the optical engineer that they put me into a very forgiving mood, and for at least the time being am very tolerant of the most annoying features of my binoculars, just feeling lucky that somebody could finally make their mind up on a compromise and actually build something!
Ron

 

[elkcub]

You're welcome, Kevin.

My earlier thread was apparently lost in the big BF system failure a year or so before. I guess I didn't realize it was the same article being discussed (couldn't download it).

 

[elkcub]

Thanks Kevin for that reference, and also Ed, for Mouroulis's paper. Both raised my conciousness of the many tradeoffs in optical design. In fact, both made me feel so sorry for the optical engineer that they put me into a very forgiving mood, and for at least the time being am very tolerant of the most annoying features of my binoculars, just feeling lucky that somebody could finally make their mind up on a compromise and actually build something!
Ron

Well put! :t:

 

[Kevin Purcell]

I'd not read the Mouroulis's paper. Strongly recommened.

I think there are a few around here you "resemble this remark":

It may come as a shock to the newly minted optical engineer to learn that optics is often a rather small part of the budget of an optical instrument and consequently receives only proportional attention.

 

[ronh]

Sort of like, given the necessary expenses of marketing, packaging, distribution, and profit, what do you think an EMPTY bag of Fritos would cost?

 

[Kevin Purcell]

Sort of like, given the necessary expenses of marketing, packaging, distribution, and profit, what do you think an EMPTY bag of Fritos would cost?

I don't think they were considering those costs (the author is a JPL instrument designer).

He is making reference to all the other important parts of the design of an optical instrument that aren't optical engineering that often get ignored by OE focused students. In bins that would be the lens mounts and adhesives; prism mounts; the focus mechanism; the bin enclosure design and manufacture; the diopter setting mechanism; all the waterproofing features; the port for injecting inert gas; production engineering; alignment systems; ergonomic design; branding; etc, etc, etc.

That well before you get to "cost of doing business".

The aerospace example he gives is given the size and mass of the device you can estimate it's cost even without a technical spec! Typical first SWAG costing.