The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 1980
Filed:
Mar. 07, 1978
Shuji Ogino, Osaka, JP;
Toshinobu Ogura, Tondabayashi, JP;
Yukio Okano, Osaka, JP;
Akiyoshi Nakamura, Sakai, JP;
Minolta Camera Kabushiki Kaisha, Osaka, JP;
Abstract
A variable soft focus lens system particularly adapted for photography is disclosed. The lens system incorporates two lens groups, a first object side lens group having an image side, rearmost surface convex to the image side, and a second, image side lens group having an object side, foremost surface concave to the object side. An airspace separating the first and second lens group has a meniscus shape concave to the object side. A good quality soft tone image having undersirable aberrations well within tolerable limits, is attained by shifting at least the second lens group along the optical axis relative to the first lens group whereby the airspace separating the two lens groups and a spherical aberration of the entire lens system is varied. An image does not lose proper focus while the spherical aberration of the system is varied. The second lens group has a refractive power within specified limits in relation to the refractive power of the entire lens system.