High resolution optical scanner

• US 5,224,088 A
• Filed: 02/10/1992
• Issued: 06/29/1993
• Est. Priority Date: 02/10/1992
• Status: Expired due to Fees

• Current Assignee: Creo Products Incorporated
• Original Assignee: Creo Products Incorporated
• Inventors: Atiya, Yossef
• Primary Examiner(s): YOUNG, WAYNE R
• Application Number:
  US07/833,215
• Time in Patent Office: 505 Days
• Field of Search: 346/76 L, 346/135.1, 369/44.18, 369/44.19, 369/97, 235/454, 359/210, 359/223-225, 358/345, 358/347, 358/348, 267/160
• US Class Current: 369/97
• CPC Class Codes: G11B 7/003 with webs , filaments or wires, e.g. belts, spooled tapes or films of quasi-infinite extent
• CPC Class Codes: G11B 7/0033 with cards or other card-like flat carriers, e.g. flat sheets of optical film
• CPC Class Codes: G11B 7/08 Disposition or mounting of heads or light sources relatively to record carriers
• CPC Class Codes: G11B 7/12 Heads, e.g. forming of the optical beam spot or modulation of the optical beam disposition or mounting of head elements within housing or with provision for moving of light source, optical beam or detector, irrelevant to the transducing method G11B7/08 ; modulating lasers H01S3/10; controlling the intensity, colour, phase, polarisation or direction of light beams arriving from an independent light source, e.g. switching gating or modulating G02F1/00

Abstract

A simple high resolution optical scanner consists of high numerical aperture lens mounted at the end of a flexible cantilever. The lens scans along a curved line as the cantilever bends. In order for the optical path to track the lens position, a mirror is mounted on the cantilever at a point located about 20% of the cantilever length, measured from the fixed mounting point. As the cantilever bends, the angle at this point is half of the angle at the cantilever end. Since the mirror doubles this angle when reflecting the input beam, the input beam will track, and stay parallel to, the lens at the end of the cantilever. This type of scanner is particularly suited to operate in a resonant mode, since the cantilever shape has low inherent damping.

Claims

1. An optical scanner comprising:

a cantilever capable of flexing;

a lens mounted at free end of said cantilever;

a mirror rigidly mounted to said cantilever at a point closer to, but not at, the fixed end of said cantilever;

a fixed incoming light beam directed towards said mirror and being reflected by said mirror towards said lens, position of said mirror chosen to keep said light beam going through said lens over the useable flexing range of said cantilever.

2. An optical scanner as in claim 1 wherein a second mirror is mounted at free end of cantilever for directing said light beam into lens.

3. An optical scanner as in claim 1 wherein said mirror is mounted at a distance between 15% to 30% of cantilever length, said distance measured from the fixed end.

4. An optical scanner as in claim 1 driven at its natural resonant frequency by electromagnetic means.

5. An optical scanner as in claim 1 wherein the material being scanned is an optical memory card.

6. An optical scanner as in claim 1 wherein the material being scanned is optical tape.