Imaging lens and imaging apparatus
AssigneeFUJIFILM Corporation
InventorTaro Asami
Life of this patent
Estimating the term…
Abstract
An imaging lens consists of, in order from the object, a negative first lens, a positive second lens, a positive third lens, a negative fourth lens, a positive fifth lens, a positive sixth lens, and a negative seventh lens. When νd7 is the Abbe's number of the material for the seventh lens, f is the focal length of the entire system, and f5 is the focal length of the fifth lens, the following conditional formulae are satisfied: νd7<55 (2) 1.25<f5/f (10).
Claims17
An imaging lens consisting of, in order from the object side, a first lens having a negative power, a second lens having a positive power, a third lens having a positive power, a fourth lens having a negative power, a fifth lens having a positive power, a sixth lens having a positive power, and a seventh lens having a negative power, wherein
- the following conditional formulae are satisfied:
- νd7<55 (2)
- 1.25<f5/f (10)
- where,
- νd7 is the Abbe's number of the material of the seventh lens with respect to the d line,
- f is the focal length of the entire system, and
- f5 is the focal length of the fifth lens.
An imaging lens consisting of, in order from the object side, a first lens having a negative power, a second lens having a positive power, a third lens having a positive power, a fourth lens having a negative power, a fifth lens having a positive power, a sixth lens having a positive power, and a seventh lens having a negative power, wherein
- the following conditional formulae are satisfied:
- νd7<55 (2)
- D4/f<0.39 (4)
- 0.65<(R10+R11)/(R10−R11) (11-1)
- where,
- νd7 is the Abbe's number of the material of the seventh lens with respect to the d line,
- f is the focal length of the entire system,
- D4 is the air space between the second lens and the third lens,
- R10 is the radius of curvature of the object-side surface of the fifth lens, and
- R11 is the radius of curvature of the image-side surface of the fifth lens.
An imaging lens consisting of, in order from the object side, a first lens having a negative power, a second lens having a positive power, a third lens having a positive power, a fourth lens having a negative power, a fifth lens having a positive power, a sixth lens having a positive power, and a seventh lens having a negative power, wherein
- the following conditional formulae are satisfied:
- D4/f<0.39 (4)
- 0.5<(R10+R11)/(R10−R11) (11)
- (R12+R13)/(R12−R13)<1.0 (12)
- where,
- f is the focal length of the entire system,
- D4 is the air space between the second lens and the third lens,
- R10 is the radius of curvature of the object-side surface of the fifth lens,
- R11 is the radius of curvature of the image-side surface of the fifth lens,
- R12 is the radius of curvature of the object-side surface of the sixth lens, and
- R13 is the radius of curvature of the image-side surface of the sixth lens.
Dependencies are inferred from the claim text.