This is an open standard that defines functional linkage between lenses and digital single-lens cameras and the mounts and image circles suitable for lens design, assuming the 4/3-type image sensor.

The Micro Four Thirds or Four Thirds system standard uses the 4/3 (four-thirds)-sized image sensor. This allows for the development of lenses specially designed for digital cameras smaller than a 35-mm single-lens camera but makes the most of the sensor performance to achieve outstanding image quality. The 4/3-type image sensor is twice the size of the 2/3-type sensor, often used in compact digital cameras, to realize quality images professionals demand. In other words, the Micro Four Thirds or Four Thirds system achieves an ideal balance of image quality and a compact, lightweight system.

This standard's major advantage is to achieve both outstanding image quality, compactness, and low weight using lenses specially designed for digital cameras. This open standard also enables each supporting company to differentiate products by developing their own unique characteristics clearly. Supporting companies can improve investment efficiency by leveraging common parts and accelerate efforts for and differentiation of new technologies. As a result, they can quickly create attractive products that make use of their color management, user interface, and proprietary technologies.

The lens must have a light beam incident angle vertical to the sensor surface and optical design that requires higher precision from the viewpoint of resolution to make the most of the imaging element's performance. Designing a lens with these features for APS or 35-mm sensors would result in a lens nearly twice the size of a conventional interchangeable one. Therefore, we believe that the 4/3-type sensor is optimal to emphasize portability, keep the interchangeable lens size the same as a conventional one, and take full advantage of the imaging sensor's performance.

For Micro Four Thirds lenses, see the product list. For details, check supporting companies' catalogues and websites. Please note the Four Thirds lenses have been discontinued.

For Micro Four Thirds cameras, see the product list. For details, check supporting companies' catalogues and websites. Please note the Four Thirds cameras have been discontinued.

The Micro Four Thirds or Four Thirds system standard does not limit the uniqueness of each supporting company. This standard intends to increase your choices by enabling each supporting company to use their originality in lens performance and functionality. Therefore, only basic performance, such as AE and AF, is standardized. For details, contact each maker.

Yes. The joint lens update service allows you to connect a camera and a lens that conform to the Micro Four Thirds or Four Thirds system standard and update their firmware via the Internet.
The joint lens update service is a joint service provided from each of the following Four Thirds members across their boundaries.

• OM Digital Solutions Corporation (OLYMPUS products)
• Panasonic Entertainment & Communications Co., Ltd.
• SIGMA Corporation
• TAMRON Co., Ltd.

The diagonal length of the Micro Four Thirds 4/3-type sensor is about half that of the 35-mm sensor. In other words, about twice the focal distance shown on the lens corresponds to the focal distance of the 35-mm sensor.

Yes, you can use a Four Thirds standard lens with a mount adapter.