The Olympus 50-200mm f/2.8-3.5 ED SWD Zuiko Zoom Lens is a high-performance zoom-telephoto lens that features, for the first time, the SWD (Supersonic Wave Drive) autofocus system. ED lens elements are used extensively to correct the color blurring that can occur when telescopic lenses are extended to their maximum focal length, while the digital-dedicated design ensures high-definition performance with clear, crisp images from edge to edge. It offers an equivalent focal length in 35mm terms of 100-400mm.

The lens' autofocus is powered by Olympus' innovative SWD focusing technology. SWD combines different technologies to provide both high speed and high precision autofocusing, while allowing the lens to be operated with lower noise than before. Optimized for use with the new E-3, this lens enables the camera to demonstrate the full power of its high-speed capability, providing extremely fast focusing.

Special optical glass elements are used to correct various types of aberrations, while the 100% digital design ensures high-definition performance with clear, crisp images from edge to edge. Close-up shooting capability is also superb, with a minimum shooting distance of just 3.9' (1.2 m) throughout the zoom range.

Supersonic Wave Drive Technology SWD technology allows for ultra-fast, whisper-quiet, high-precision AF. Two compact, high-powered SWD devices power autofocus at an ultra-high speed by exciting unique elliptical oscillations, while an ultra-compact 5.3mm x 4.3mm optical encoder detects and controls the lens drive position using direct rotation detection without reduction gear. This enables it to achieve a level of precision that's accurate to 5 microns (5/1000 mm). When used in combination with the E-3, which offers improved AF computation and lens-body communication rates, the SWD motors provide the fastest focusing speed of approximately 170 ms (0.17 seconds). High Optical Quality Features 3 ED elements to correct for various types of aberrations. Internal Focus Internal Focus system makes focusing smoother and faster.