Optical tracking system and tracking method using the same

Patent metadata

Field	Value
Publication number	US-2016287341-A1
Application number	US-201414391447-A
Country	US
Kind code	A1
Filing date	Apr 29, 2014
Priority date	Apr 30, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

An optical tracking system and a method using the same capable of detecting an exact spatial position and a direction of a target regardless of the distance from the target to be calculated is disclosed. The optical tracking system and a method using the same according to an embodiment of the present invention has an effect of expanding an available area by detecting an exact spatial position and a direction of a target regardless of the distance from the target to be calculated, as well as, a system downsizing is also achieved by significantly reducing size of the marker unit compared with conventional system.

First claim

1 . An optical tracking system comprising:
at least one marker unit attached on a target, and emitting a parallel light to form an enlarged image of a pattern portion which is included inside the marker unit; at least one image forming unit receiving the parallel light of the pattern portion emitted from the marker unit and forming the enlarged image of the pattern portion; and a processor calculating a spatial position and a direction of the marker unit by using the enlarged image of the pattern portion formed on the image forming unit.

2 . The optical tracking system of claim 1 , wherein the marker unit comprises:
at least one pattern portion formed by plurality of patterns; at least one light source irradiating a light toward the pattern portion; and at least one first lens portion releasing the light, which is emitted from the light source and passes the pattern portion or is reflected by the pattern portion, to be the parallel light form to the image forming unit.

3 . The optical tracking system of claim 1 , wherein the processor calculates the spatial position of the marker unit by using a position and a size change of the enlarged image of the pattern portion formed on the image forming unit, and calculates the direction of the marker unit by using a position and a size change of the pattern for each area of the enlarged pattern portion.

4 . The optical tracking system of claim 3 , wherein the processor calculates the spatial position of the marker unit by comparing the position and the size of the enlarged pattern portion formed on the image forming unit with a pre-stored reference position and reference size of an image of a reference pattern portion; and
calculates the direction of the marker unit by comparing the position of the pattern for each area and the size of the pattern of the enlarged image of the pattern portion with a pre-stored reference pattern position and a reference pattern size for each area of the image of the pattern portion.

5 . The optical tracking system of claim 1 , wherein the marker unit reflects and releases the light, which is emitted from the at least one light source, in the parallel light form through a ball lens, in which a pattern portion is wholly or partially formed on a surface.

6 . The optical tracking system of claim 1 , wherein the marker unit passes and releases the light, which is emitted from the at least one light source and is reflected by or has passed the pattern portion, in parallel light form through a fish-eye lens.

7 . The optical tracking system of claim 1 , wherein the marker unit passes and releases the light, which is emitted from the at least one light source and is reflected by or has passed the pattern portion, in parallel light form through an objective lens and releases the parallel light through a prism to have with different angle of view.

8 . The optical tracking system of claim 1 , wherein the marker unit reflects and releases the light, which is emitted from the at least one light source, in parallel light form through a mirror portion on which a pattern portion is formed.

9 . The optical tracking system of claim 8 , wherein the marker unit further comprises a first lens arranged at an interval from the mirror portion to change and release the parallel light, which is reflected by the mirror portion, once more in a parallel light form.

10 . The optical tracking system of claim 9 , wherein the marker unit further comprises an aperture installed on the mirror portion to adjust an angle of view and a resolution of the enlarged image of the pattern portion formed on the image forming unit by adjusting a light quantity of the light which is incident on the mirror portion.

11 . The optical tracking system of claim 8 , wherein the mirror portion is a mirror with a spherical or non-spherical shape.

12 . A tracking method comprising:
emitting a parallel light of a pattern portion from a marker unit which is attached on a target to form an enlarged image of the pattern portion; receiving the parallel light emitted from the marker unit and forming the enlarged image of the pattern portion on an image forming unit; and calculating a spatial position and a direction of the marker unit through a processor by using the enlarged image of the pattern portion formed on the image forming unit.

13 . The tracking method of claim 12 , wherein calculating the spatial position and the direction of the marker unit comprises:
calculating the direction of the marker unit by calculating a rotated angle of the marker unit through the processor by using the enlarged image of the pattern portion formed on the image forming unit; and calculating the spatial position of the marker unit through the processor by using the enlarged image of the pattern portion formed on the image forming unit and the rotated angle of the marker unit.

14 . The tracking method of claim 13 , wherein calculating the direction of the marker unit comprises:
measuring a position of the pattern portion and a size change of the pattern portion for each area of the enlarged image of the pattern portion formed on the image forming unit through the processor; and calculating the rotated angle of the marker unit by comparing a position and a size of the reference pattern portion for each area, which are pre-stored in the processor, with the position of the pattern portion for each area and the size change of the pattern portion of the enlarged image of the pattern portion formed on the image forming unit.

15 . The tracking method of claim 13 , wherein calculating the spatial position of the marker unit comprises
measuring a position and a size of the enlarged image of the pattern portion formed on the image forming unit through the processor; and calculating the spatial position of the marker unit through the processor by comparing a reference position and a reference size of the image of the pattern portion which are pre-stored in the processor with the position and the size of the enlarged pattern portion formed on the image forming unit.

16 . The tracking method of claim 12 , wherein the marker unit comprises:
at least one pattern portion formed by plurality of patterns; at least one light source irradiating light toward the pattern portion; and at least one first lens portion releasing the light, which is emitted from the light source and have passed the pattern portion or is reflected by the pattern portion, in parallel light form to the image forming unit.

17 . The tracking method of claim 12 , wherein the marker unit reflects and releases the light, which is emitted from the at least one light source, in parallel light form through a ball lens in which a pattern portion is wholly or partially formed on a surface of the ball lens.

18 . The tracking method of claim 12 , wherein the marker unit passes and releases the light, which is emitted from the at least one light source and is reflected by or has passed the pattern portion, in parallel light form through a fish-eye lens.

19 . The tracking method of claim 12 , wherein the marker unit passes and releases the light, which is emitted from the at least one light source and is reflected by or has passed the pattern portion, in parallel light form through an objective lens, and releases the parallel light through a prism to have different angle of view.

20 . The tracking method of claim 12 , wherein the marker unit reflects and releases the light, which is emitted from the at least one light source, in a parallel l

Assignees

• Koh Young Tech Inc
• Kyungpook Nat Univ Industry-Academic Coop Found

Inventors

• Hong Jong-Kyu
• Lee Hyun-Ki
• Kim Min-Young
• Chae You-Seong

Classifications

• A61B34/20 Primary

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• A61B2090/3945

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• A61B2090/3983

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• A61B2034/2055

  Optical tracking systems · CPC title

• A61B2034/2065

  Tracking using image or pattern recognition · CPC title