Handwriting Systems and Operation Methods Thereof

• US 20130162592A1
• Filed: 10/30/2012
• Published: 06/27/2013
• Est. Priority Date: 12/22/2011
• Status: Abandoned Application

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: CHENG, HAN-PING, YANG, SHU-SIAN
• Application Number:
  US13/663,470
• Publication Number:
  US 20130162592A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A handwriting system includes a light source module, an image sensing apparatus and a processing circuit. The light source module is configured to provide a light source to illuminate an object on a plane. The image sensing apparatus is disposed on the plane and configured to capture an image of the object reflecting the light source. The processing circuit is electrically connected to the image sensing apparatus and configured to receive the image captured by the image sensing apparatus, analyze the shape of each of light spot(s) in the captured image and filter out the light spot(s) not qualified to the shape of the object. Another handwriting system and two handwriting system operation methods are also provided.

Claims

1. A handwriting system, comprising:

a light source module configured to provide a light source to illuminate an object on a plane;

an image sensing apparatus disposed on the plane and configured to capture an image of the object reflecting the light source; and

a processing circuit electrically connected to the image sensing apparatus and configured to receive the image captured by the image sensing apparatus, analyze the shape of each of light spot(s) in the captured image and filter out the light spot(s) not qualified to the shape of the object.

2. The handwriting system according to claim 1, wherein the processing circuit is further configured to convert the captured image into a binary image and determine the binary image whether or not having any light spot qualified to the shape of the object by using Hough Transform.

3. The handwriting system according to claim 1, wherein the light source module comprises:

a laser source configured to generate a spot light source; and

an optical element configured to convert the spot light source into a linear light source serving as the light source.

4. The handwriting system according to claim 3, wherein the optical element comprises a cylindrical lens or a Micro Electro Mechanical System scanning mirror, the cylindrical lens is configured to convert the spot light source into the linear light source serving as the light source, and the Micro Electro Mechanical System scanning mirror is configured to change the emitting direction of the spot light source and thereby forming the light source.

5. The handwriting system according to claim 1, wherein the light source module comprises:

a plurality of laser light sources arranged in parallel and configured to emit light and thereby forming the light source.

6. The handwriting system according to claim 1, wherein the plane is a parallelogram.

7. The handwriting system according to claim 1, wherein the plane comprises a virtual panel.

8. An operation method of a handwriting system, the handwriting system comprising a light source module and an image sensing apparatus, the light source module being configured to provide a light source to illuminate an object on a plane, the image sensing apparatus being disposed on the plane and configured to capture an image of the object reflecting the light source, the operation method comprising:

obtaining the image captured by image sensing apparatus;

analyzing the shape of each of light spot(s) in the captured image; and

filtering out the light spot(s) not qualified to the shape of the object.

9. The operation method according to claim 8, further comprising:

converting the captured image into a binary image and determining, by using Hough Transform, the binary image whether or not having any light spot qualified to the shape of the object.

10. A handwriting system, comprising:

a light source module configured to provide a light source to illuminate at least one object on a plane;

an image sensing apparatus disposed on the plane and configured to capture an image of the object(s) reflecting the light source; and

a processing circuit, electrically connected to the image sensing apparatus, configured to receive the image captured by the image sensing apparatus and calculate, if the captured image has a single light spot therein, the position of a single object relative to the plane according to image characteristics and imaging position of the single light spot in the captured image, wherein the processing circuit, when operating in an operation zone converting mode, is further configured to define an indicated operation zone according to at least two positions sequentially inputted by an object and map a predetermined operation zone of the handwriting system to the indicated operation zone through performing a coordinate transform by using a matrix operation.

11. The handwriting system according to claim 10, wherein the processing circuit is further configured to calculate, if the captured image has a plurality of light spots therein, the positions of a plurality of objects relative to the plane according to image characteristics and imaging position of the light spots in the captured image, wherein the processing circuit, when operating in the operation zone converting mode, is further configured to define the indicated operation zone according to four positions sequentially inputted by two individual objects, the two objects each are associated with two positions.

12. The handwriting system according to claim 10, wherein the processing circuit is further configured to calculate, if the captured image has a plurality of light spots therein, the positions of a plurality of objects relative to the plane according to image characteristics and imaging position of the light spots in the captured image, wherein the processing circuit, when operating in the operation zone converting mode, is further configured to define the indicated operation zone according to four positions inputted at the same time by four individual objects.

13. The handwriting system according to claim 10, wherein the matrix operation comprises a homogeneous matrix operation.

14. The handwriting system according to claim 10, wherein the light source module comprises:

a laser source configured to generate a spot light source; and

an optical element configured to convert the spot light source into a linear light source serving as the light source.

15. The handwriting system according to claim 14, wherein the optical element comprises a cylindrical lens or a Micro Electro Mechanical System scanning mirror, the cylindrical lens is configured to convert the spot light source into the linear light source serving as the light source, and the Micro Electro Mechanical System scanning mirror is configured to change the emitting direction of the spot light source and thereby forming the light source.

16. The handwriting system according to claim 10, wherein the light source module comprises:

a plurality of laser light sources arranged in parallel and configured to emit light and thereby forming the light source.

17. The handwriting system according to claim 10, wherein the plane is a parallelogram.

18. The handwriting system according to claim 10, wherein the plane comprises a virtual plane.

19. An operation method of a handwriting system, the handwriting system comprising a light source module and an image sensing apparatus, the light source module being configured to provide a light source to illuminate at least one object on a plane, the image sensing apparatus being disposed on the plane and configured to capture an image of the object(s) reflecting the light source, the operation method comprising:

obtaining the image captured by the image sensing apparatus;

calculating, if the captured image has a single light spot therein, the position of a single object relative to the plane according to image characteristics and imaging position of the single light spot in the captured image; and

defining, when the handwriting system operates in an operation zone converting mode, an indicated operation zone according to at least two positions sequentially inputted by one object and mapping a predetermined operation zone of the handwriting system into the indicated operation zone through performing a coordinate transform by using a matrix operation.

20. The operation method according to claim 19, further comprising:

calculating, if the captured image has a plurality of light spots therein, the positions of a plurality of objects relative to the plane according to image characteristics and imaging position of the light spots in the captured image; and

defining, when the handwriting system operates in the operation zone converting mode, the indicated operation zone according to four positions sequentially inputted by two individual objects, wherein the two objects each are associated with two positions.

21. The operation method according to claim 19, further comprising:

calculating, if the captured image has a plurality of light spots therein, the positions of a plurality of objects relative to the plane according to image characteristics and imaging position of the light spots in the captured image; and

defining, when the handwriting system operates in an operation zone converting mode, the indicated operation zone according to four positions inputted at the same time by four individual objects.

22. The operation method according to claim 19, wherein the matrix operation comprises a homogeneous matrix operation.