Method and apparatus for eliminating optical sensor flickering in video gaming systems
Synchronizing a shutter control signal of an optical sensor device of a video gaming system with a horizontal retrace signal generated by a game console of the system such that the frame rate of the optical sensor device is synchronized to the horizontal retrace signal. Synchronizing the frame rate to the horizontal retrace signal eliminates or reduces the occurrence of random stripes in the images captured by the optical sensor device, commonly known as flickering.
1 . An apparatus for eliminating or reducing flickering in a video gaming system, the apparatus comprising:
a game console, the game console generating a horizontal retrace signal;
an input device in communication with the game console, the input device receiving the horizontal retrace signal from the game console, the input device having an optical sensor device, wherein the optical sensor device commences capturing of an image of at least a portion of a display screen upon receiving an asserted shutter control signal, and wherein the shutter control signal is synchronized with the horizontal retrace signal such that a frame rate of the optical sensor device is synchronized to the horizontal retrace signal.
2 . The apparatus of claim 1 , wherein the optical sensor device has a shutter size that is constant from one frame to the next, the shutter size corresponding to a number of rows of the display screen that are captured by the sensor device when the shutter control signal is asserted.
3 . The apparatus of claim 2 , wherein the shutter control signal is asserted when it is at a logic one level.
4 . The apparatus of claim 2 , wherein the shutter control signal is asserted when it is at a logic zero level.
5 . The apparatus of claim 2 , wherein the shutter size is less than a total number of rows of the display screen.
6 . The apparatus of claim 2 , wherein the shutter size is equal to or greater than a total number of rows of the display screen.
7 . A method for eliminating or reducing flickering in a video gaming system, the method comprising:
in a game console, generating a horizontal retrace signal;
in an input device in communication with the game console, receiving the horizontal retrace signal from the game console, the input device having an optical sensor device, wherein the optical sensor device commences capturing of an image of at least a portion of a display screen upon receiving an asserted shutter control signal; and
synchronizing the shutter control signal with the horizontal retrace signal.
8 . The method of claim 7 , wherein the optical sensor device has a shutter size that is constant from one frame to the next, the shutter size corresponding to a number of rows of the display screen that are captured by the sensor device when the shutter control signal is asserted.
9 . The method of claim 7 , wherein the shutter control signal is asserted when it is at a logic one level.
10 . The method of claim 7 , wherein the shutter control signal is asserted when it is at a logic zero level.
11 . The method of claim 7 , wherein the shutter size is less than a total number of rows of the display screen.
12 . The method of claim 7 , wherein the shutter size is equal to or greater than a total number of rows of the display screen.
13 . A computer program for eliminating or reducing flickering in a video gaming system, the program being embodied on a computer-readable medium, the program comprising:
instructions for receiving a horizontal retrace signal from a game console in an input device;
instructions for synchronizing a shutter control signal with the horizontal retrace signal, the shutter control signal controlling when the optical sensor device commences capturing of an image of at least a portion of a display screen.