High relative aperture objective lens system with compound focusing
OwnerPierre Angenieuxinventor
Life of this patent
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Abstract
A high relative aperture objective lens system with a compound focusing system, comprising four lens components of varying respective distances, in which the first component is of positive refractive power, the second component is of positive refractive power, the third component is of negative refractive power, and the fourth component is of positive refractive power. The lens system is designed so that focusing is produced by translating the second and fourth components, the aberrations--and notably coma--being well corrected throughout the whole focusing distance range.
Claims8
A high relative aperture objective lens system with compound focusing, comprising four lens components axially arranged, from the front to the rear of the lens system, so that the first lens component is of positive refractive power, the second lens component is of positive refractive power, the third lens component is of negative refractive power and the fourth lens component is of positive refractive power, the said second lens component having a convex front surface and a concave rear surface, the said third lens component being made of two parts separated by an air gap, the front part of the said third lens component being of negative refractive power and having a concave rear surface and the rear part of the said third lens component having a concave front surface and a convex rear surface, whereby the said objective lens system performs focusing by simultaneously translating forward the said second and fourth lens components only when the object moves from infinity to a finite distance, the translation of the said second lens component being of lesser amplitude than that of the said fourth lens component.
Dependencies are inferred from the claim text.