A file exchange site for lens designs
A library of lens designs is helpful for the optical engineer. Tasks that can benefit from such a library include choosing a starting point for a new design, finding benchmarks for an existing design, and assessing design targets. Many optical engineers have spent significant time building their own individual libraries; these individual libraries are instructive to the designer but are necessarily limited in scope and unlimited in time demands. Other libraries are for sale. These commercial libraries can be quite comprehensive, but the designer misses out on the lessons learned from building the library himself.
This site is intended to build a better design library, by building on collaborative efforts of its users. A large library can be built by making the site collaborative; users can learn from others' efforts via discussions and release notes. Please participate in this collaboration.
All designs are in the public domain, either in patents or publications. All design files submitted to the site must also be in the public domain.
This site is owned and operated by Daniel J. Reiley, Ph.D. You can contact me on my gmail account: dan dot reiley, or at my LinkedIn account.
July 1, 2022 - Major addition: 295 *more* photographic lenses contributed by Bill Claff (and linked to production lenses!)
Today I posted 295 models, all from the prolific Bill Claff, from www.photonstophotos.net These models have a heavy emphasis on older products, many of them now treasured classics. On the primes page, I describe a little bit about why photographers appreciate these older lenses and make a comparison between a modern lens and a vintage lenses with similar focal length and f/#
Some of these older lenses are unusual. Two (US004948236 & US002681594) deliberately have a lot of spherical aberration, to produce soft images. Two are extremely long supertelephotos (DE02206106 & US003743384).; check out Richard Haw’s disassembly of one of them
June 18, 2921 - Major addition: 438 ptographic lenses contributed by Bill Claff (and linked to production lenses!)
Bill Claff contributed 438 models of photographic objectives from his website www.PhotonsToPhotos.net. His site is an optical engineering gem. It includes a wealth of technical information on photography and photographic equipment. He has measurements on dozens of photographic cameras’ dynamic range, read noise, and gain. This sensor data is aggregated into a quality score for portrait, landscape, and sports photography. There’s technical information on photographic issues such as close-ups, panoramics, polarizers, flash, and post processing. There’s also good primers on optics and sensors, as well as an excellent section on photographic lenses.
Bill’s section on lenses is most relevant to this site. He’s built an interactive raytracing tool, using real raytracing in Java script to allow users to slide aperture, field, or zoom to see the effect of ray intercepts, field curvature, and paraxial lens properties. Even more helpful for this site, Bill has correlated lens product schematics to lens design patents from around the world.
This correlation between production lenses and lens design patents is particularly helpful to lens designers for several reasons. First, product realization implies a very high degree of design maturity; implemented designs always represent an optimum some kind engineering optimization. Next, many online resources are available for these production lenses, allowing a lens designer to connect optical designs to physical observations of the lenses.
Two of my favorite resources for such physical observations are www.lensrentals.com and www.kenrockwell.com. LensRentals offers both well-measured MTF data and detailed teardowns. The MTF measurements offer an obvious link to Zemax calculations. The teardowns offer fascinating views into the optomechanical implementation of these lens designs. Ken Rockwell offers well-reasoned lens reviews from a photographer’s perspective, as well as tough looks at chromatic aberration, vignetting, distortion, and stray light. On the Primes page I show how Ken’s observed ghost image in a Sigma lens can be traced to a particular ray path for a matching Sigma lens patent. On the Zooms page, I show how breakage of an element in a Canon lens is consistent with the material properties of that element in a matching Canon lens patent. Please share your observations on the Comments page.
Bill was kind enough to contribute his work to-date. For the most-recent work, keep an eye on his site.
May 1, 2021 - 11 Zoom lenses posed from Iain Neill’s recent paper
Iain Neill is giant in the field of lens design for cinematography. His dozens of patents scooped and many papers represent important milestones in the field. He's earned many international awards for his work. His recent paper, “Evolution of zoom lens optical design technology and manufacture,” in Optical Engineering puts these milestones in the perspective of zoom lenses’ historical development. Such historical reviews are always interesting, but a review curated by such a luminary deserves close study. I hope the files posted on the Zooms page will be helpful in such studies.
February 7, 2021 - 38 designs posted from Braat & Török's Imaging Optics
Joseph Braat has had an illustrious career in optics, including 25 years at Philips Research Labs and 10 years at TU Delft., producing over 150 papers and patents. Peter Torok is similarly distinguished, currently serving as a professor at both Imperial College London and NTU Singapore., teaching and doing research in a wide range of imaging optical technology and science.
Their book, Imaging Optics, covers theory of electromagnetic waves and its application to the diffraction theory of image formation, while gracefully including geometrical optics as a bridge between the two. This broad range of closely-related topics is difficult to learn and even more difficult to link; this book provides an excellent resource for anyone trying to learn the theory or practice of this science.
For this site, I am particularly thankful for their selection of photolithography systems (posted on the Projector page) and systems for optical data storage (posted to the microscopes page.) I had deliberately avoided building models from patens for such systems because there are so many patents in this space; it's hard to tell which patents are illustrative of the systems in practice. Considering the authors' extensive experience in these fields, I suspect that the selected models are especially relevant.
I thank Professor Braat for considering this addition. It's exactly the kind of posting I had in mind when I started the site, and I've enjoyed working with him as we made our way through some technical and bureaucratic challenges.
January 1, 2021 - Upgraded to New Google Sites
Google has forced this change on me. I originally built this site using Google Sites. A few years ago, Google announced that they'd make this service obsolete, requiring everyone to migrate to New Google Sites. I delayed this migration as long as I could because New Google Sites deals poorly with tables, which are a large part of www.lens-designs.com. I delayed as long as I could, but now I have to make the change.
The change has many advantages. Most importantly, the links to the designs are now in a Google drive and the design summaries are now in Google Sheets. This change should simplify users' export of the summaries, enabling people to modify their sort criteria easily. For example, people may prefer sorting telescopes by field of view instead of focal length and image height.
The change also has some drawbacks. Tables in my previous analysis are now listed as plain text. Depending on the browser window, the navigation pane may be hidden from the left pane.
Please note that a few extra steps are necessary to download files. This process is not obvious or self-explanatory, so I wrote some instructions on the Downloading page anyway.
Finally, I've temporarily removed the Discussion page. I'll add it again once the rest of the page is working well again.
November 10, 2019 - 73 models posted from the Handbook of Optics
The Handbook of Optics, from the Optical Society of America, is a tremendously valuable resource for all optics practitioners. Each chapter is a great introduction for a specific optics subspecialties. Chapters relevant to lens design include Doug Goodman’s chapter on Generic Principles of Geometric Optics, Glenn Boreman’s chapter on Transfer Function Techniques, Barry Johnson’s chapter on Lenses, and William Wetherell’s chapter on Afocal Systems.. Of particular interest to this site are Betensky, Kreitzer, and Moskovich’s ’s chapter on Camera Lenses and Lloyd Jones’s chapter on Reflective and Catadioptric designs. Both of these chapters are primarily comprised of prescriptions for a wide variety of lens designs. Each chapter also includes some insightful text to explain the designs and place them in context. Models posted to the Primes page, the Zooms page, and the telescopes page are constructed from these prescriptions. For the most part, I’ve avoided sharing insights into these designs; to get this insight, please buy the book.
February 8, 2017 - 59 zoom lenses posted, including 5 by Obama
This posting puts the total number of files over 1000. Please join the conversation by contributing your files, thoughts, or requests.
February 2, 2017 - More instructions on downloading and using files
Most of the comments have been from people having difficulty using files downloaded from this site. I believe most of the problems are with browser settings and .zmx file structure. Visit the page on loading files for details.
January 26, 2017 - 40 models for smartphone lenses posted
I think the correct term is “mobile imaging,” but it will always be a phone to me, even if it has a great camera. I posted the files on the Primes page.
April 8, 2016 - 55 zoom lens designs posted..
Today I posted 56 zoom lens files. All are for folded zooms, which provide an interesting study. As I described in a paper at the 2014International Optical Design Conference, this class of optics is interesting be they are of a reasonable complexity that the designs are likely to be instructive, they offer a small range of design constraints because of the standardization of CMOS imager sizes and the mechanical constraints imposed on DSC cameras, and there is enough recent activity in awarded patents that a representative sample of contemporary designs can be collected. You can find the design files and some analysis on the page for zoom lenses.
October 28, 2015 - 95 full frame photographic objectives posted..
These lenses all have a 42mm image circle, fitting the full-frame images found on high end photography cameras. Focal lengths range from 15 to 925mm. I find them interesting because they tend to achieve excellent image quality without heavy use of aspheres, making them good benchmarks for other custom optical systems. Analysis on the primes page also shows the distribution of glass types and paraxial properties for these lenses.
April 25, 2015 - 45 eyepiece designs posted today.
My recent addition of design files from Cox included many eyepiece designs, the newest of which was published 50 years ago. Today's posting broadens this sampling to include modern designs, too. The older designs compare surprisingly well.
February 28, 2015 - 32 new files submitted by Steve Eckhardt
These files include 12 projectors and 18 prime photo lenses. He has also submitted a scan lens and a spectrograph, spurring me to add pages for these categories.
Steve Eckhardt is president of Eckhardt Optics LLC, which he describes as “your ODM partner for optics. Our custom lenses are designed in the US and manufactured in China. We deliver prototypes optics with related metal parts in four weeks and production quantities in eight. Our rigid quality control provides the reliability you need for success.” Please visit http://www.eckop.com for more information.
January 21, 2015 - 25 design files for microscope objectives added
These files represent a wide variety of objectives, typical 40X objectives, high-magnification immersion objectives, low magnification objectives for inspection microscopes, and some unusual catadioptric objectives, too. You can find them, as well as a little summary, on the page for Microscope Objectives.
November 19, 2014 - Major update: more than 500 new files added
There’s a major update today - the addition of over 500 files based on the design examples from Cox’s “A System of Optical Design.” 300 files are in Oslo format, submitted by Michael Gauvin from Lambda Research Corporation. 227 are files that I built independently in Zemax format. Most of the files are photographic primes, so I put a little summary there. 65 files are eyepieces, so I placed them on that page.
September 15, 2014 - New section on IP, plus 24 projector design files posted
Two updates today: First, to clarify the IP status of posted material, I’ve added a page with some links describing IP issues, as well as my understanding of how these issues relate to me. Second, I’ve uploaded 24 projector design files to the projectors page, showing a variety of projector types.
September 5, 2014 - 25 Double Gauss designs posted
For the first posting to this site, I’ve chosen double-gauss designs, posted to the Photographic Primes page. These Zemax models are all based on patent literature; they include the original patent, from 1897, modern patents, from 2013, and a nice sampling from in-between.