“Panasonic will offer the first camera in a new format called Micro Four Thirds. Its mission: to put the photographic quality of an S.L.R. into a compact body”.
Why not just say it’s the world’s smallest S.L.R.? Because technically, it’s not an S.L.R. Panasonic achieved the space savings by performing a radical boxectomy. That is, it removed the box containing the mirror and prism that traditionally bend the lens’s light up to your eye (the “reflex” system that gives an S.L.R. its name). Without that contraption, the camera loses nearly an inch of depth. The lens can now be placed much closer to the light sensor, and therefore the lens itself is much smaller.
And yet the sensor itself — a crucial factor in picture quality — remains full size. At 0.9 inches diagonally, this 12-megapixel sensor is not quite as big as the Nikon’s (1.1 inches), but it’s still S.L.R.-worthy — and much bigger than a typical compact camera’s sensor (usually about 0.4 inches).