Did Sigma design the Olympus M.Zuiko 75mm F1.8?
It's an open secret that many compact cameras are produced by OEMs - companies that produce large numbers of products that are then sold under other brand names. Tamron, for example, builds lens/sensor modules that form the basis of many compacts. Companies such as Asia Optical and Sanyo DI Solutions build compacts that are then sold under a range of brand names. The practice isn't confined to compacts, though, with distinctly Tamron-esque lenses appearing in big brands' lineups, for example. But we were still surprised to read about Sigma's latest patent for a 75mm F1.8 prime lens...
The patent, highlighted on the egami blog, shows the details of a 75mm F1.8 prime, specifically designed with a lightweight internal focus element to allow fast focusing for stills and movies. That's a combination of features that sounded somewhat familiar.
|Sigma's patented 75mm F1.8, 10 element, nine group lens design|
|The 10 element, nine group design used in the Olympus m.Zuiko 75mm F1.8|
And, while that could be because it's essentially a text-book definition of how to design a high-quality lens for contrast detection AF systems, a look at the optical formula diagram offers more convincing evidence to support the idea that Sigma designed the Olympus m.Zuiko 75mm F1.8 - one of the best lenses for the Micro Four Thirds system.