The focus of our listing of Olympus prime lenses is on their current models designed for the "Four Thirds" system, which is the basis of all current Olympus digital SLRs. These modern Olympus prime lenses have all been designed especially for use in digital cameras, with special anti-reflection coatings, and optical designs that deliver light to the sensor nearly perpendicular to its surface. If you find any current Olympus prime lens missing from this list, please let us know, by email, at . (Since older Olympus primes aren't compatible with the Four Thirds mount of the current cameras, we have no plans to list them here.)