Patent ID: 7920331

Claim:
An anamorphic converter that projects an image at magnification ratios that are different from each other in a main magnification direction and a sub-magnification direction, comprising, in order from a projected-surface side: a first group having one or more lens elements and a negative power at least in the main magnification direction; and a second group having one or more lens elements and a positive power at least in the main magnification direction, wherein of optical surfaces, a last surface of the first group and a first surface of the second group: [1] have a power in both main magnification and sub-magnification directions; [2] are convex toward the projected-surface side in both main magnification and sub-magnification directions in a region having an area that is ¼ or more of an optical effective region area including a center portion of each of the last and first optical surfaces; and [3] at least one of the last and first optical surfaces is a free curved surface.