Objective lens holder for an objective lens driving device capable of thinning an optical pickup unit
AssigneeMitsumi Electric Co., Ltd.
InventorTsukasa Yamada
Life of this patent
Estimating the term…
Abstract
An objective lens holder for use in an objective lens driving device of a symmetry type has an upper member and a lower member assembled with the lower member. The lower member has a pair of main bobbin portions for winding two tilting coils and two focusing coils. The pair of main bobbin portion is symmetrically disposed with respect to an optical axis of a laser beam. The upper member and the lower member have openings for passing through the laser beam. Each of the upper member and the lower member has four hook portions for winding four tracking coils.
Claims14
An objective lens holder for holding an objective lens, said objective lens holder being for use in an objective lens driving device of a symmetry type, said objective lens holder comprising:
- an upper member;
- and
- a lower member assembled with said upper member;
- wherein said lower member comprising a pair of main bobbin portions for winding two tilting coils and two focusing coils, said pair of main bobbin portion being symmetrically disposed with respect to an optical axis of a laser beam;
- said upper member and said lower member having openings for passing through said laser beam;
- and
- each of said upper member and said lower member having four hook portions for winding four tracking coils.
An objective lens driving device of a symmetry type comprising:
- an objective lens;
- an objective lens holder for holding said objective lens, said objective lens holder comprising an upper member and a lower member which are assembled with each other, said lower member having a pair of main bobbin portions symmetrically disposed with respect to an optical axis of a laser beam, said upper member and said lower member having openings for passing through said laser beam, each of said upper member and said lower member having four hook portions;
- two tilting coils wound around said pair of main bobbin portions;
- two focusing coils wound around said pair of main bobbin portions so as to overlay said two tilting coils;
- four tracking coils wound around said four hook portions;
- a damper base apart from said objective lens holder in a tangential direction;
- a suspension member elastically supporting said objective lens holder with respect to said damper base, said suspension member consisting of a plurality of suspension wires disposed on both sides of said damper base and said objective lens holder;
- and
- a magnetic circuit for applying driving forces to said two tilting coils, said two focusing coils, and said four tracking coils according to energizing to said two tilting coils, said two focusing coils, and said four tracking coils.
Dependencies are inferred from the claim text.