Code-based, electromagnetic-field-responsive graphic data-acquisition system

• US 5,623,129 A
• Filed: 07/27/1994
• Issued: 04/22/1997
• Est. Priority Date: 11/05/1993
• Status: Expired due to Term

• Current Assignee: Polyvision Corporation (Steelcase Incorporated)
• Original Assignee: Microfield Graphics, Inc. (Steelcase Incorporated)
• Inventors: Mallicoat, Samuel W.
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): LOOMIS, PAUL A
• Application Number:
  US08/282,034
• Time in Patent Office: 1,000 Days
• Field of Search: 178/18, 178/19, 345/173, 345/175, 359/202, 359/227, 364/709.1, 364/709.11
• US Class Current: 178/19.01
• CPC Class Codes: B41J 2/471 using dot sequential main scanning by means of a light deflector, e.g. a rotating polygonal mirror
• CPC Class Codes: G02B 26/125 Details of the optical system between the polygonal mirror and the image plane G02B26/123, G02B26/127 take precedence; F-Theta lenses G02B13/0005
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 3/0423 using sweeping light beams, e.g. using rotating or vibrating mirror
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

An electromagnetic-field-responsive (preferably optical), code-based, graphic data-acquisition system for tracking the operational status of a mobile write-effective component (stylus, eraser, etc.) in relation to a defined writing-surface area. The preferred embodiment features an active optical structure which is disposed adjacent the writing-surface area for creating, by scanning, a defined zone of optical radiation, optically reactive, retroreflective code structure which is joined to the mobile component and which is capable of reacting (reflecting the same) to radiation within the zone when the code structure intersects the zone, a reaction monitoring structure for monitoring the reaction behavior of the code structure and for producing a related response, and interpretation structure which acquires that response and determines therefrom the desired operational-status-tracking information. Modification to this preferred structure are also illustrated and discussed.

Claims

1. A writing path tracking system comprising:

a flat board having an erasable writing surface;

a writing implement including a pigment supply in communication with a tip capable of contact-initiated removable pigment deposit on the writing surface, and a light reflective, character-indicative, code pattern disposed on a surface of the implement;

a scanning light-beam-source disposed adjacent the writing surface and operable to generate a defined pattern of scanned light in a scanning zone, spaced closely and generally parallel to the writing surface so that the code pattern of the implement is located in the scanning zone when the tip of the implement is contacting the writing surface;

light-reflection monitoring structure positioned adjacent the writing surface and capable of receiving light reflectance signals from the code pattern and converting the signals into an analog data stream indicative of implement position and character;

a processor communicatively connected to the monitoring structure and capable of receiving, digitizing and interpreting the data stream, then displaying at a location remote from the board, an image-reproduction corresponding to an actual written image on the board.

2. The system of claim 1 wherein the scanning light-beam-source includes at least a first laser scanner and a second laser scanner, each scanner being spaced apart from the other scanner around a peripheral region of the writing surface.

3. The system of claim 1 wherein the code pattern indicates one of the following qualities of the implement:

pigment color, line width, inclination relative to the writing surface.

4. The system of claim 1 wherein the code pattern is a bar code disposed around a circumferential surface of the implement.

5. The system of claim 1 wherein the board is a dry-erase whiteboard.

6. The system of claim 1 further comprising

a plurality of writing implements, each implement carrying a supply of pigment for contact-initiated deposit on the writing surface, and having a differentiating reflective code pattern denoting a characteristic of the pigment.

7. The system of claim 6 wherein the characteristic of the pigment is color.

8. A writing implement comprising;

an elongate body having a peripheral surface near a writing tip, and containing a pigment supply accessible to the writing tip;

a code pattern disposed on the peripheral surface of the body, wherein the code pattern indicates at least one characteristic of either the pigment or the writing tip; and

wherein the code pattern is circumferentially constant so that the code pattern can be interpreted by a scanner-monitoring device to provide the same characteristic information regardless of which side of the implement is exposed to the scanner-monitoring device.

9. The writing implement of claim 8 wherein the code pattern indicates the color of the pigment.

10. The writing implement of claim 8 wherein the code pattern indicates at least one geometrical feature of the writing tip.

11. A plurality of writing implements, each implement according to claim 8, wherein its code structure differentiates it from the other implements.