Resources Contact Us Home Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE     Zoom lens Image Number 11 for United States Patent #6646815. A zoom lens, comprises: three lens groups including a first lens group having a negative refracting power, a second lens group having a positive refracting power and a third lens group having a positive refracting power arranged serially in this order from the object side. The second lens group comprises a positive lens, a cemented lens including a positive lens and a negative lens and one lens arranged serially in this order from the object side. The following conditional expression is satisfied;where f.sub.2 represents a focal length of the second lens group and f.sub.w represents a focal length of the total optical system at a wide-angle end.       Recently Added Patents Storage system, control device and storage device Anchor stud and method of forming an anchor stud Electro-conductive member for electrophotography, electrophotographic apparatus, and process cartridge Molecular separators, concentrators, and detectors preparatory to sensor operation, and methods of minimizing false positives in sensor operations Sheet conveyance device, and image forming apparatus and image reading unit including same System and method for configuring access to electronic mailboxes Method of forming polysilicon, thin film transistor using the polysilicon, and method of fabricating the thin film transistor   Randomly Featured Patents Production method of capsinoid by dehydrating condensation, stabilizing method of capsinoid, and capsinoid composition Wavelet based intercept attribute for seismic exploration Plastic magnet injection molding machine Container for transporting a blister package Level shift circuit Foldable tire changing mat Hydraulic brake system controlling slip Random moving toy simulating pursuit by toy animal Apparatus for straightening weft yarns in fabrics Ultrasonic transducer © 2006-2008 PatentGenius. All Rights Reserved.