Olympus Optical Co. Ltd. renamed Olympic Coroporation in October 2003, unifying the corporate name and the well-known brand. The company is a leading manufacturer of digital cameras, with a large range of compact digital cameras. Olympus is the designer of the Four-Thirds System standard for digital single-lens reflex camera design and development, which uses the same frame size as the PEN cameras. Since its foundation Olympus has also been a manufacturer of microscopes and optics for specialised needs, such as medical use.