Optically imaging pen configured for calculating accurate nib positions

• US 8,112,339 B2
• Filed: 06/16/2011
• Issued: 02/07/2012
• Est. Priority Date: 05/25/1999
• Status: Expired due to Fees

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Lapstun, Jacqueline Anne, Silverbrook, Kia, Lapstun, Paul
• Primary Examiner(s): HAMILTON, LALITA M
• Application Number:
  US13/162,533
• Publication Number:
  US 20110240733A1
• Time in Patent Office: 236 Days
• Field of Search: 705/21, 705/23, 705 33- 35, 705 38- 39, 705/53, 705/56, 705/58, 705/62, 705/67, 705/70, 705 72- 73, 705/79, 705/40
• US Class Current: 705/35
• CPC Class Codes: G06F 3/0321 by optically sensing the absolute position with respect to a regularly patterned surface forming a passive digitiser, e.g. pen optically detecting position indicative tags printed on a paper sheet constructional details of pen-shaped pointing devices G06F3/03545, G06F3/03542, G06F3/037
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text
• CPC Class Codes: G06Q 20/10 specially adapted for electronic funds transfer [EFT] systems; specially adapted for home banking systems
• CPC Class Codes: G06Q 20/102 Bill distribution or payments
• CPC Class Codes: G06Q 40/00 Finance; Insurance; Tax strategies; Processing of corporate or income taxes
• CPC Class Codes: G06V 10/12 Details of acquisition arrangements; Constructional details thereof
• CPC Class Codes: G06V 30/1423 the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32
• CPC Class Codes: G08C 21/00 Systems for transmitting the position of an object with respect to a predetermined reference system, e.g. tele-autographic system

Abstract

An optically imaging pen for interacting with a printed substrate. The pen includes: a nib for interacting with the printed substrate; an image sensor for imaging an area of the printed substrate to provide image data; a processor configured for: (i) identifying target elements in the image data and inferring a perspective transform due to a tilt of the pen; (ii) acquiring and decoding coded data contained in the image data; (iii) calculating a nib position using a tag location, the perspective transform and a known geometry of pen optics; and (iv) generating digital ink based on the nib position.

Claims

1. An optically imaging pen for interacting with a printed substrate, said printed substrate including human-readable content and a plurality of contiguous tags, each tag having a plurality of target elements, each tag containing coded data indicative of a substrate identity and of a tag location on the substrate, said pen comprising:

a nib for interacting with the printed substrate;

an image sensor for imaging an area of the printed substrate to provide image data; and

a processor configured for;

(i) identifying target elements in the image data and inferring a perspective transform using perspective distortion of the target elements due to a tilt of the pen;

(ii) acquiring and decoding the coded data contained in the image data, the decoded coded data identifying the substrate identity and the tag location on the substrate;

(iii) calculating a nib position using the tag location, the perspective transform and a known geometry of pen optics, said nib position being different than the tag location; and

(iv) generating digital ink identifying the nib position and the substrate identity.

2. The optically imaging pen of claim 1, further comprising a force sensor for detecting a nib force.

3. The optically imaging pen of claim 1, wherein processor is configured to interpret said nib force as pen-up or pen-down state with respect to the printed substrate.

4. The optically imaging pen of claim 1, wherein said pen contains a unique pen identity.

5. The optically imaging pen of claim 1, wherein said digital ink comprises one or more pen strokes representing handwriting on the substrate.

6. The optically imaging pen of claim 1, wherein said image sensor is offset from said nib.

7. The optically imaging pen of claim 1, further comprising a transceiver for communicating the digital ink to a computer system, such that the computer system can interpret the digital ink and perform an action in response to the interaction with the printed substrate.