The Four Thirds System is a digital camera standard that was developed in partnership between Olympus and Kodak for their Digital SLR and mirrorless camera systems, although it was primarily used by Olympus there were also two Panasonic four thirds cameras and one made by Leica.
Four thirds lenses are designed to fit cameras using the four thirds system from Olympus and Panasonic.
The Micro Four Thirds System replaced the Four Thirds system in 2008 when it was jointly developed by Olympus and Panasonic for use on their digital mirrorless compact system cameras. Micro four thirds cameras use the same sensor as four thirds cameras but do away with the mirror mechanism so they can be made significantly smaller, lighter & more compact.
Micro four thirds lenses are available at Park Cameras from Olympus and Panasonic as well as third party manufactures including Samyang, Sigma and Voigtlander.
Lenses for the micro four thirds system for Olympus Pen cameras and Olympus OM-D cameras are compact and easy to carry, making a pro photographers’ kit bag smaller and more portable. Built for micro four thirds mirrorless cameras, these lenses offer a shallower depth of field and a beautifully smooth bokeh, as well as being bright and crisp to deliver stunning images.