US 7,321,471 B2
Lens barrel and lens system
Takayuki Kuroki, Saitama (Japan)
Assigned to Tamron Co., Ltd., Saitama (Japan)
Filed on Sep. 18, 2006, as Appl. No. 11/522,417.
Claims priority of application No. 2005-270420 (JP), filed on Sep. 16, 2005.
Prior Publication US 2007/0064319 A1, Mar. 22, 2007
Int. Cl. G02B 15/14 (2006.01); G03B 17/00 (2006.01)
U.S. Cl. 359—699  [359/694; 359/695; 359/698; 359/700; 359/701; 359/704; 359/706; 396/79; 396/84] 8 Claims
OG exemplary drawing
 
1. A lens system comprising
a foremost group of lens elements closest to the object,
a rearmost group of lens elements farthest from the object,
a first fixed barrel,
a linearly-shuttling barrel residing inside the first fixed barrel so as to be slidable along the optical axis, for carrying the rearmost group of lens elements,
a cam barrel having at least two types of cams and residing outside the first fixed barrel so as to be rotatable about the optical axis,
a second fixed barrel residing outside the cam barrel, linearly-sliding studs positioned in a forward edge of the linearly-shuttling barrel closer to the object, and
a lens barrel residing over an inner surface of the second fixed barrel so as to be slidable thereover and provided with linear grooves in which the linearly-sliding studs are fitted, for carrying the foremost group of lens elements.