Optical pickup actuator, optical pickup employing the optical pickup actuator, and optical recording and/or reproducing apparatus employing the optical pickup

Abstract

An optical pickup actuator which can compensate for a curvature of a disc, an optical pickup employing the optical pickup actuator, and an optical recording/reproducing apparatus employing the optical pickup. The optical pickup actuator includes a base having a holder, a bobbin mounting an objective lens, a plurality of elastic supports having one end coupled to the holder and another end coupled to the bobbin such that the bobbin is movably supported, and a magnetic driving portion which drives the bobbin in a focusing direction and for a tracking direction. The plurality of elastic supports includes inner elastic supports that are positioned on a side of the optical pickup actuator closest to a center of the disc and outer elastic supports that are positioned on an opposite side of the optical pickup actuator closest to an outer perimeter of the disc, and the inner elastic supports and outer elastic supports have different lengths.

What is claimed is:  
     
         1 . An optical pickup actuator for use with a disc, comprising: 
 a holder;    a bobbin to mount an objective lens; and    a plurality of asymmetrical elastic supports movably supporting the bobbin such that B type radial rolling is substantially eliminated to compensate for a curvature of the disc.    
     
     
         2 . An optical pickup actuator for use with a disc, comprising: 
 a holder;    a bobbin to mount an objective lens;    a magnetic driving portion to drive the bobbin in a focusing direction and/or a tracking direction; and    a plurality of asymmetrical elastic supports movably supporting the bobbin such that the bobbin driven by the magnetic driving portion produces only A and C type radial rolling to compensate for a curvature of the disc.    
     
     
         3 . An optical pickup for use with a disc, comprising: 
 an objective lens; and    a pickup actuator to control a movement of the objective lens and to record information on and/or to reproduce information from the disc, wherein the pickup actuator comprises: 
 a holder;  
 a bobbin to mount an objective lens; and  
 a plurality of asymmetrical elastic supports movably supporting the bobbin such that B type radial rolling is substantially eliminated to compensate for a curvature of the disc.  
   
     
     
         4 . An optical pickup for use with a disc, comprising: 
 an objective lens; and    a pickup actuator to control a movement of the objective lens and to record information on and/or to reproduce information from the disc, wherein the pickup actuator comprises: 
 a holder;  
 a bobbin to mount an objective lens;  
 a magnetic driving portion to drive the bobbin in a focusing direction and/or a tracking direction; and  
 a plurality of asymmetrical elastic supports movably supporting the bobbin such that the bobbin driven by the magnetic driving portion produces only A and C type radial rolling to compensate for a curvature of the disc.  
   
     
     
         5 . An optical recording/reproducing apparatus for use with a disc, comprising: 
 a spindle motor which rotates the disc;    an optical pickup movably disposed in a radial direction with respect to the disc by a pickup actuator;    a driving portion to drive the spindle motor and the optical pickup; and    a controlling portion to control a movement of the optical pickup, wherein the pickup actuator comprises: 
 a holder;  
 a bobbin to mount an objective lens; and  
 a plurality of asymmetrical elastic supports movably supporting the bobbin such that B type radial rolling is substantially eliminated to compensate for a curvature of the disc.  
   
     
     
         6 . An optical recording/reproducing apparatus for use with a disc, comprising: 
 a spindle motor which rotates the disc;    an optical pickup movably disposed in a radial direction with respect to the disc by a pickup actuator;    a driving portion to drive the spindle motor and the optical pickup; and    a controlling portion to control a movement of the optical pickup, wherein the pickup actuator comprises: 
 a holder;  
 a bobbin to mount an objective lens;  
 a magnetic driving portion to drive the bobbin in a focusing direction and/or a tracking direction; and  
 a plurality of asymmetrical elastic supports movably supporting the bobbin such that the bobbin driven by the magnetic driving portion produces only A and C type radial rolling to compensate for a curvature of the disc.