Lens actuator
AssigneeFujitsu Limited
InventorsYukio Hirai, Akihiko Makita, Gorou Kawasaki, Nobuyuki Kanto
Life of this patent
Estimating the term…
Abstract
A lens actuator of an optical head for an optical disc drive includes a two-dimensional actuator supported by a carriage via a spring, a second lens held by the two-dimensional actuator, a slider supported by the two-dimensional actuator and floated off a turning optical disc, and a first lens held by the slider. A laser beam is focused on the optical disc by an object lens system which includes the first lens and the second lens. The slider is supported by the two-dimensional actuator via a support having a predetermined spring constant in the focus directions while also having freedom to follow tilting of the optical disc.
Claims12
A lens actuator of an optical head for an optical disc drive comprising:
- an actuator supported by a carriage via a spring and driven to displace at least in focus directions;
- a second lens unit including at least one lens held by the actuator;
- a slider supported by the actuator and floated off a turning optical disc via an air bearing;
- and a first lens including at least one lens and held by the slider;
- whereby a laser beam is focused on the optical disc by means of an object lens system which includes the first lens and the second lens;
- wherein the slider is supported by the actuator via a support having a predetermined spring constant in the focus directions while also having freedom to follow tilting of the optical disc;
- and
- wherein the support for supporting the slider on the actuator has a resonance frequency higher than a resonance frequency of the spring for supporting the actuator on the carriage and lower than a resonance frequency of the air bearing formed between the slider and the optical disc.
A lens actuator of an optical head for an optical disc drive comprising:
- an actuator supported by a carriage via at least one first spring and driven to displace at least in focus directions;
- a second lens unit including at least one lens held by the actuator;
- a slider supported by the actuator via at least one second spring and floated off a turning optical disc via an air bearing;
- and
- a first lens including at least one lens and held by the slider,
- whereby a laser beam is focused on the optical disc by means of an object lens system which includes the first lens and the second lens,
- wherein the lens actuator further comprises a third spring interposed between the slider and said at least one second spring, the slider being supported by the actuator to follow tilting of the optical disc, and
- wherein said at least one second spring for supporting the slider on the actuator has a resonance frequency higher than a resonance frequency of said at least one first spring for supporting the actuator on the carriage and lower than a resonance frequency of the air bearing formed between the slider and the optical disc.
Dependencies are inferred from the claim text.