Frasable optical wallet-size data card

• US 4,810,868 A
• Filed: 07/13/1987
• Issued: 03/07/1989
• Est. Priority Date: 08/06/1985
• Status: Expired due to Term

• Current Assignee: LaserCard Corp. (Assa Abloy AB)
• Original Assignee: Drexler Technology Corporation (Assa Abloy AB)
• Inventors: Drexler, Jerome
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): Fuller, Leon K.
• Application Number:
  US07/072,307
• Time in Patent Office: 603 Days
• Field of Search: 235/487, 235/488, 235/456, 235/468, 235/470, 235/440, 235/454, 346/76 L, 346/135.1, 283/74, 283/94, 283/904, 365/106
• US Class Current: 235/487
• CPC Class Codes: G06K 1/12 otherwise than by punching
• CPC Class Codes: G06K 19/06018 one-dimensional coding
• CPC Class Codes: G06K 19/06046 Constructional details
• CPC Class Codes: G06K 19/14 the marking being sensed by radiation
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G11B 11/10584 characterised by the form, e.g. comprising mechanical protection elements
• CPC Class Codes: G11B 7/0033 with cards or other card-like flat carriers, e.g. flat sheets of optical film

Abstract

A data card having an optical recording medium formed by an erasable layer atop a polymer layer with prerecorded indicia, all atop a card base. The polymer layer has surface contours which constitute prerecorded indicia. The erasable layer disposed over the polymer layer displays the prerecorded indicia for reading, together with information on the erasable strip. The erasable material may be magnetooptical material, amorphous-crystalline material or liquid crystal material.

Claims

1. An optical data card comprising,

a wallet-size plastic card base having opposed major surfaces,

a photopolymer layer disposed over a major surface of the card base, said layer having surface relief patterns of characteristic maximum height above said major surface therein defining prerecorded information, said prerecorded information formed in a permanent manner in said layer,

an erasable optical recording layer disposed over at least a portion of the photopolymer layer, and

a transparent protective layer disposed over the optical recording layer, the protective layer being substantially thicker than said characteristic height.

2. The data card of claim 1 wherein said erasable recording layer comprises magnetooptical material.

3. The data card of claim 1 wherein said erasable recording layer comprises a film capable of amorphous to crystalline transitions.

4. The data card of claim 1 wherein said erasable recording layer is a liquid crystal material.

5. The data card of claim 1 wherein said photopolymer is photoresist.

6. The data card of claim 1 wherein said surface relief pattern comprises a plurality of ridges extending over portions of said major surfaces.

7. In a data card of the type having a wallet-size plastic card base with opposed major surfaces, the improvement comprising,

a photopolymer underlayer disposed over a major surface of the card base, said layer having prerecorded information defined therein, said prerecorded information being defined in a permanent manner,

an erasable optical recording layer disposed over at least a portion of the photopolymer layer, said erasable layer revealing underlying prerecorded information, and

a transparent protective layer disposed over the optical recording layer.

8. The data card of claim 7 wherein said erasable recording layer comprises magnetooptical material.

9. The data card of claim 7 wherein said erasable recording layer comprises a film capable of amorphous to crystalline transitions.

10. The data card of claim 7 wherein said erasable recording layer is a liquid crystal material.

11. The data card of claim 7 wherein said photopolymer is photoresist.

12. In a data card of the type having a wallet-size plastic card base with opposed major surfaces, the improvement comprising,

a photoresist underlayer disposed over a major surface of the card base, said layer having prerecorded information defined therein by relief-type patterns of characteristic maximum height above said major surface, said prerecorded information being defined in a permanent manner,

an erasable optical recording layer comprising magnetooptical material disposed over at least a portion of the photoresist layer, said erasable layer revealing underlying prerecorded information, said prerecorded information being unchanged during erasing of said optical recording layer, and

a transparent protective layer disposed over the optical recording layer.