Scanning head including a magneto-optical element and scanning device including the scanning head

• US 5,726,964 A
• Filed: 07/13/1995
• Issued: 03/10/1998
• Est. Priority Date: 09/23/1994
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Van Kesteren, Hans W., Ruigrok, Jacobus J. M.
• Primary Examiner(s): Ben, Loha
• Application Number:
  US08/501,833
• Time in Patent Office: 971 Days
• Field of Search: 369/112, 369/110, 369/116, 369/13, 369/44.23, 359/245, 359/246, 359/251, 359/252, 359/254, 359/258, 359/255, 359/280, 359/281, 359/282, 365/121, 365/122, 365/55, 365/33, 365/66, 365/45, 365/157, 360/114, 360/112, 360/125
• US Class Current: 369/110.01
• CPC Class Codes: G11B 11/10547 interacting with the magnetisation of an intermediate transfer element, e.g. magnetic film, included in the head

Abstract

Scanning head including a magneto-optical element and scanning device including the scanning head. A scanning head having a head face (1) comprises flux-guiding elements (3a, 3b) and a magneto-optical element (5). The magneto-optical element is disposed in a gap plane (4) which extends between flux-guiding elements.

Claims

1. A scanning head having a head face for scanning an information medium for reading information recorded in the information medium, which scanning head comprises a magneto-optical sensor element, and at least two magnetic flux-guiding elements, for guiding magnetic flux from the information medium being scanned through the head face to the magneto-optical sensor element, the flux guiding elements having facing planar surfaces which are spaced apart from one another to form a gap plane which extends therebetween, and the magneto-optical sensor element disposed in the gap plane which extends between the flux-guiding elements, characterized in that the two flux guiding elements border on the head face and the magneto-optical element is situated at a distance from the head face.

2. A scanning head as claimed in claim 1, characterized in that a portion of at least one flux-guiding element, which portion is situated opposite the magneto-optical element, is optically transparent.

3. A scanning head as claimed in claim 2, characterized in that the magneto-optical element is in close contact with flux-guiding element.

4. A scanning head as claimed in claim 2, characterized in that two flux-guiding elements border on the head face, the gap plane extends between the two flux-guiding elements which border on the head face, and a third flux-guiding element which is situated at a distance from the head face, and the magneto-optical element is disposed opposite a gap which extends between the flux-guiding elements which border on the head face.

5. A scanning head as claimed in claim 1, characterized in that the magneto-optical element is in close contact with a flux-guiding element.

6. A scanning head as claimed in claim 1, characterized in that a portion of one of the flux-guiding elements which border on the head face, which portion bridges the distance between the head face and the magneto-optical element which is situated at a distance from the head face, has a shape which projects away from the other flux-guiding element which borders on the head face.

7. A scanning head as claimed in claim 1, characterized in that the two flux-guiding elements which border on the head face overlap one another only near the magneto-optical element which is situated at a distance from the head face.

8. A scanning head as claimed in claim 1, characterized in that two flux-guiding elements border on the head face, the gap plane extends between the flux-guiding elements which border on the head face, and a third flux-guiding element which is situated at a distance from the head face, and the magneto-optical element is disposed opposite a gap which extends between the two flux-guiding elements which border on the head face.

9. A scanning head as claimed in claim 1, characterized in that a winding extends between the at least two flux-guiding elements.

10. A scanning device comprising the scanning head as claimed in claim 1, and further comprising a light source, a light path for directing a polarized optical beam generated by the light source to the magneto-optical element, and a detector for measuring a change of the light beam after reflection from the magneto-optical element.