Browse Prior Art Database

Fully Adjustable Focus Offset and Tilt Focus Actuator

IP.com Disclosure Number: IPCOM000116866D
Original Publication Date: 1995-Nov-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Gardner, T: AUTHOR [+3]

Abstract

An optical storage focus actuator design allowing for adjustment of both tilt and height is disclosed. The approach is quite simple.

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Fully Adjustable Focus Offset and Tilt Focus Actuator

      An optical storage focus actuator design allowing for
adjustment of both tilt and height is disclosed.  The approach is
quite simple.

      In optical storage devices, the focus actuator contains the
high numerical aperture objective lens.  Tight control on both the
tilt and the height of the objective lens with respect to the media
is necessary.  Tilt controls the level of comatic aberration, while
height is important because it is desirable to have the objective
operate about the center of the actuator's focus stroke.  Fig. 1
shows what is typical in the industry.  The focus actuator pivots
about a ball and socket with two screws used to adjust the tilt.  Any
tilt can be affected, but the resulting height of the actuator is
then fixed.

      Disclosed is a method which allows for both tilt and height
control.  The approach is quite simple and is shown in Fig. 2.  Three
screws and springs are used without the ball and socket approach
mentioned above.  Obviously, any height and tilt combination can be
achieved.