Optical: systems and elements – Lens – With variable magnification
Reexamination Certificate
2008-08-06
2009-12-08
Thompson, Timothy J (Department: 2873)
Optical: systems and elements
Lens
With variable magnification
C359S686000
Reexamination Certificate
active
07630145
ABSTRACT:
A zoom lens has, in order from the object side to the image side, a first lens unit that does not move during zooming and has positive refractive power, a second lens unit that performs zooming and has negative refractive power, a third lens unit that corrects image plane variation caused by zooming and has negative refractive power, and a fourth lens unit that does not move during zooming and has positive refractive power. The first lens unit has, in order from the object side to the image side, a first lens subunit that does not move during focusing and has negative refractive power, a second lens subunit that is configured to move along the optical axis during focusing and has positive refractive power, a third lens subunit that does not move during focusing and has positive refractive power. The second lens subunit has at least one aspherical lens surface AS12.
REFERENCES:
patent: 5745300 (1998-04-01), Usui et al.
patent: 5986820 (1999-11-01), Usui et al.
patent: 6124982 (2000-09-01), Usui
patent: 6545818 (2003-04-01), Usui et al.
patent: 2003/0007256 (2003-01-01), Usui et al.
patent: 2008/0239504 (2008-10-01), Tsutsumi
patent: 6-242378 (1994-09-01), None
patent: 11-030749 (1999-02-01), None
patent: 2001-021804 (2001-01-01), None
Nakamura Tomoyuki
Wakazono Tsuyoshi
Canon Kabushiki Kaisha
Canon USA Inc IP Div
Thompson Timothy J
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