Leica Camera Ag

Kathrin Keller

Stefan Roth

Uwe Reinstädtler

A wide-angle objective in accordance with the invention comprises, in an order from an object-side end to an image-side end, a front group of total positive refractive power having at least four lenses; a middle group of total positive refractive power having at least three lenses; and a rear group of total positive refractive power having at least three lenses, wherein the quotient of the focal length of the front group and the total focal length of the objective amounts to between 2.28 and 2.79, the quotient of the focal length of the middle group and the total focal length of the objective amounts to between 3.02 and 3.69, and the quotient of the focal length of the rear group and the total focal length of the objective amounts to between 3.50 and 4.29.

Wide-angle photographic objective

Described is a wide-angle slip-on viewfinder () on rangefinder cameras for analog and digital wide-angle recordings of different image recording formats with lenses of different focal lengths, comprising three lens groups (LG, LG, LG), a frame/mask unit () and a partially transmissive prism cube () which is designed as a combination element, wherein, on the light entrance side () in the viewfinder beam path (), a first lens group (LG) has a negative refractive power and the second and third lens groups (LG, LG) have a positive refractive power, wherein the second lens group (LG) is composed of a first lens (L) arranged downstream of the first lens group (LG) and a second lens (L) arranged on the light exit side () and the partially transmissive prism cube () is arranged between the lenses (L, L) and the third lens group (LG) is arranged in a mask imaging beam path () which is at right angles to the viewfinder beam path () between the frame/mask unit () and the partially transmissive prism cube ().

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Lahnau, Germany

Kathrin Keller