Large aperture ratio photographic lens with means for correcting aberrations
AssigneeNippon Kogaku K.K.
InventorYoshinari Hamanishi
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AssigneeNippon Kogaku K.K.
InventorYoshinari Hamanishi
Estimating the term…
This specification discloses a large aperture ratio photographic lens with means for correcting aberrations comprising a forward group including at least one negative lens and having a composite positive refractive power, a rearward group also including at least one negative lens and having a composite positive refractive power, and a diaphragm provided between the two groups, characterized in that during the shift from an infinity object photography condition to a short distance object photography condition, focusing is effected by moving both of the two groups toward the object side while enlarging the diaphragm space between the two groups and that the photographic lens satisfies predetermined conditions.
In a large aperture ratio photographic lens with means for correcting aberrations comprising a forward group including at least one negative lens and having a composite positive refractive power, a rearward group also including at least one negative lens and having a composite positive refractive power, and a diaphragm provided between said two groups, the improvement residing in that during the shift from an infinity object photography condition to a short distance object photography condition, focusing is effected by moving both of said two groups toward the object side while enlarging the diaphragm space between said two groups and that said photographic lens satisfies the following conditions:
Dependencies are inferred from the claim text.