Patent US4948230A successfully refreshed from Google Patents.
US4948230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Objective lens driving apparatus
Assignee: Toshiba Corp
•
Filing: 1989-03-09
•
Granted: 1990-08-14
•
Expires: 2009-03-09
Abstract
Abstract An objective lens driving apparatus is provided which can restrain hysteresis phenomena in the relationship between semi-static displacements and forces in a focusing direction of the objective lens. The apparatus can also maintain the balance of force even when the objective lens is shifted in a focusing or tracking direction. Thus, the objective lens can be readily prevented from tilting. The apparatus also has a simplified configuration that can readily start up control operations in servomechanism. Thus, stable control characteristics of the apparatus can be achieved.
Inventors
- 👤 Akihiro Kasahara
- 👤 Akira Yamada
- 👤 Katsutoshi Wada
- 👤 Hideo Yamasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:39
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0925; G11B7/0932
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
193 words
An objective lens driving apparatus comprising: an objective lens; a movable unit having a center of gravity for supporting said objective lens; means for moving said movable unit with respect to a stationary unit in a direction of an optical axis of said objective lens; a pair of means for rotating said movable unit being provided on symmetrical positions with respect to the center of gravity; a first supporting-rod pair for supporting said movable unit with respect to said stationary unit, said first supporting-rod pair comprising two supporting rods disposed in parallel with each other within a plane being in parallel with the optical axis of said objective lens; a second supporting-rod pair for supporting said movable unit with respect to said stationary unit, said second supporting-rod pair comprising two supporting rods disposed in parallel with each other within a plane being different from the plane of said first supporting-rod pair, and being in parallel with the optical axis of said objective lens; and said first and second supporting-rod pairs being disposed such that an intersecting line of the planes including respectively said first and second supporting-rod pairs passes through said movable unit.
Claim 2
Dependent Claim
193 words
An objective lens driving apparatus comprising: an objective lens; a movable unit having a center of gravity for supporting said objective lens; means for moving said movable unit with respect to a stationary unit in a direction of an optical axis of said objective lens; a pair of means for rotating said movable unit being provided on symmetrical positions with respect to the center of gravity; a first supporting-rod pair for supporting said movable unit with respect to said stationary unit, said first supporting-rod pair comprising two supporting rods disposed in parallel with each other within a plane being in parallel with the optical axis of said objective lens; a second supporting-rod pair for supporting said movable unit with respect to said stationary unit, said second supporting-rod pair comprising two supporting rods disposed in parallel with each other within a plane being different from the plane of said first supporting-rod pair, and being in parallel with the optical axis of said objective lens; and said first and second supporting-rod pairs being disposed such that an intersecting line of the planes including respectively said first and second supporting-rod pairs passes through said movable unit.
Claim 3
Dependent Claim
41 words
An objective lens driving apparatus of claim 1, wherein the intersecting line of the two planes respectively including said first and second supporting-rod pairs is caused to substantially coincide with a line parallel thereto and passing through the center of gravity.
Claim 4
Dependent Claim
31 words
An objective lens driving apparatus of claim 1, wherein said first and second supporting-rod pairs are disposed in parallel with a plane perpendicularly intersecting the optical axis of said objective lens.
Claim 5
Dependent Claim
24 words
An objective lens driving apparatus of claim 1, wherein two planes respectively including said first and second supporting-rod pairs intersect each other substantially perpendicularly.
Claim 6
Dependent Claim
27 words
An objective lens driving apparatus of claim 1, wherein said movable unit is disposed between the respective parallel supporting rods of said first and second supporting-rod pairs.
Claim 7
Dependent Claim
31 words
An objective lens driving apparatus of claim 5, wherein at least partial portions of surroundings of the supporting rods of said first and second supporting-rod pairs are surrounded with viscoelastic materials.
Claim 8
Dependent Claim
16 words
An objective lens driving apparatus of claim 6, wherein the viscoelastic materials are of gel silicone.
Claim 9
Dependent Claim
18 words
An objective lens driving apparatus of claim 1, wherein said supporting rods are formed by an elastic material.
Claim 10
Dependent Claim
29 words
An objective lens driving apparatus of claim 1, wherein the supporting rods of said first and second supporting-rod pairs are disposed so as to pass through said movable unit.
Claim 11
Dependent Claim
20 words
An objective lens driving apparatus of claim 9, wherein viscoelastic materials are packed into piercing holes of said movable unit.
Claim 12
Dependent Claim
16 words
An objective lens driving apparatus of claim 10, wherein the viscoelastic materials are of gel silicone.
Claim 13
Dependent Claim
33 words
An objective lens driving apparatus of claim 9, wherein the supporting rods of said first and second supporting-rod pairs are disposed to intersect with each other at piercing portions of said movable unit.
Claim 14
Dependent Claim
31 words
An objective lens driving apparatus of claim 1, wherein at least partial portions of surroundings of the supporting rods of said first and second supporting-rod pairs are surrounded with viscoelastic materials.
Claim 15
Dependent Claim
16 words
An objective lens driving apparatus of claim 13, wherein the viscoelastic materials are of gel silicone.
Claim 16
Dependent Claim
17 words
An objective lens driving apparatus of claim 1, wherein said movable unit has a rigid block shape.
References Cited (Backward Citations)
US4592037A
Cited
JPS59221839A
Cited
JPS60197942A
Cited
US4750164A
Cited
US4767187A
Cited
US4782475A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-13 | 1994-02-12 | 1994-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-13 | 1998-02-12 | 1998-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-13 | 2002-02-12 | 2002-08-14 | $7700.00 | Window Closed / Lapsed |