Olympus's original pancake prime for MFT — 34mm equiv at f/2.8 in body-cap dimensions.
The Olympus M.Zuiko Digital 17mm f/2.8 was released in 2009 as the first MFT pancake prime, providing a 34mm full-frame equivalent perspective in a 22mm deep barrel. Six elements in 4 groups. Five rounded aperture blades. 37mm filter thread. At 71g. 0.20m MFD.
The optical design uses 6 elements in 4 groups (aspherical elements). Five rounded aperture blades. The 37mm filter thread. At 71g the lens is very lightweight. Minimum focus distance of 0.20m. MSC autofocus motor (quiet, suited to video). f/2.8 maximum aperture. MFT image circle (34mm equivalent).
The 17mm f/2.8 established the MFT pancake form factor in 2009: the shallow barrel depth paired with compact MFT bodies like the Olympus PEN series enabled a jacket-pocket mirrorless system combination. The 34mm equivalent perspective provides a near-normal to slight-wide field of view. The later 17mm f/1.8 (2012) replaced it in Olympus's lineup with a brighter aperture and MSC AF.
On the used market the Olympus M.Zuiko Digital 17mm f/2.8 is very affordable as the original MFT pancake prime. Condition checks: AF response, 37mm front element for marks. Compatible with all Micro Four Thirds bodies.