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
Stack and folding-typed electrode assembly and method for preparation of the same
Semiconductor devices and methods for changing operating characteristics and semiconductor systems including the same
Input system including position-detecting device
Error recovery storage along a memory string
Mass spectrometry device and method using ion-molecule reaction ionization
Instantaneous single click perpetual date mechanism
Aggregating completion messages in a sideband interface
  Randomly Featured Patents
Chemical-mechanical polish machines and fabrication process using the same
State detection device for detecting abnormal operation of a high-frequency magnetron heating apparatus
Methods and apparatus for scalable array processor interrupt detection and response
User interface in an ultrasound system
Content processor
Damascene structure with reduced capacitance using a boron carbon nitride passivation layer, etch stop layer, and/or cap layer
Core array and periphery isolation technique
Communications interface and floating devices including such an interface
Injector with finger ring
Low-glare rear-view mirror for vehicles