(19)
(11)EP 2 287 648 A3

(12)EUROPEAN PATENT APPLICATION

(88)Date of publication A3:
06.12.2017 Bulletin 2017/49

(43)Date of publication A2:
23.02.2011 Bulletin 2011/08

(21)Application number: 10171595.1

(22)Date of filing:  02.08.2010
(51)Int. Cl.: 
G02B 13/04  (2006.01)
G02B 15/177  (2006.01)
G02B 13/16  (2006.01)
G02B 27/00  (2006.01)
(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR
Designated Extension States:
BA ME RS

(30)Priority: 17.08.2009 JP 2009188460
08.07.2010 JP 2010156009

(71)Applicant: Canon Kabushiki Kaisha
Tokyo 146-8501 (JP)

(72)Inventor:
  • MAEDA, Yuuki
    Tokyo Tokyo 146-8501 (JP)

(74)Representative: TBK 
Bavariaring 4-6
80336 München
80336 München (DE)

  


(54)Optical system and optical apparatus having the same


(57) An optical system includes, in order from an enlargement conjugate side to a reduction conjugate side via a largest air gap, a front unit (Lf) having a negative power, and a rear unit (Lb) having positive power. The optical system satisfies 1.75<Ndn1<2.05, 0.02<θgFn1-(0.6438-0.001682×νdn1)<0.08, and 2.5<|fn1/F|<5.0, where fn1 represents a focal length of a negative lens (L18) in the front unit, Ndn1 represents a refractive index of a material of the negative lens, νdn1 represents an Abbe number of the material of the negative lens, θgFn1 represents a partial dispersion ratio of the material of the negative lens, and F represents a focal length of the optical system.