Patent Document ID: 9411431
Application ID: 11951251
Patent Status: 1

Claim One:
1. A tracking device for tracking a position of the tracking device in relation to a surface, the tracking device comprising: (i) a first optical sensor disposed near a first corner of the tracking device, (ii) a second optical sensor disposed near a second corner of the tracking device, (iii) a third optical sensor disposed near a third corner of the tracking device, and (iv) a fourth optical sensor disposed near a fourth corner of the tracking device, wherein each of the first optical sensor, the second optical sensor, the third optical sensor and the fourth optical sensor is configured to capture respective images of the surface while the tracking device is moved over the surface, wherein (i) the first corner is diagonally opposite to the third corner such that the first optical sensor and the third optical sensor are disposed on two diagonally opposite corners of the tracking device, and (ii) wherein the second corner is diagonally opposite to the fourth corner such that the second optical sensor and the fourth optical sensor are disposed on two diagonally opposite corners of the tracking device, wherein (i) the first corner and the second corner are on a first edge of the tracking device, (ii) the second corner and the third corner are on a second edge of the tracking device, (iii) the third corner and the fourth corner are on a third edge of the tracking device, and (iv) the fourth corner and the first corner are on a fourth edge of the tracking device, and wherein the first optical sensor, the second optical sensor, the third optical sensor and the fourth optical sensor are sequentially activated to capture respective images in a time alternated sequence such that (i) subsequent to activating the first optical sensor, the first optical sensor is deactivated and the third optical sensor is activated, (ii) subsequent to activating the third optical sensor, the third optical sensor is deactivated and the fourth optical sensor is activated, (iii) subsequent to activating the fourth optical sensor, the fourth optical sensor is deactivated and the second optical sensor is activated, and (iv) subsequent to activating the second optical sensor, the second optical sensor is deactivated and the first optical sensor is activated.