Browse Prior Art Database

Optical Head Employing Concave Lens for Optical Disk Drive

IP.com Disclosure Number: IPCOM000118027D
Original Publication Date: 1996-Aug-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 42K

Publishing Venue

IBM

Related People

Hirasaka, Y: AUTHOR [+3]

Abstract

Disclosed is a method for the reduction of actuator height of optical disk drives.

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This is the abbreviated version, containing approximately 100% of the total text.

Optical Head Employing Concave Lens for Optical Disk Drive

      Disclosed is a method for the reduction of actuator height of
optical disk drives.

      Fig. 1 shows an example of this apparatus.  A collimated
optical beam comes (1) from the optical head (2) to a concave lens
(3).  The beam is changed, diverging beam (4), by the concave lens
(3).  The beam (4) is bent by a beam bender (5).  After that, the
beam is focused on an optical disk (6) by an objective lens (7).
Fig. 2 shows  an example of the effect this method.  The dotted lines
show this method  and the normal lines show an example of the common
method which employed  the infinite optical system before the
objective lens.  By this method,  about 10% height reduction can be
achieved.  Figs. 3 and 4 show the other  ways of obtaining the same
effect.  In Fig. 3, the concave lens (8) is  located between the beam
bender (9) and the objective lens (10).  In Fig. 4, the convex beam
bender (11) is applied instead of the concave lens.