Optical communication systems with displays

An optical communication system, comprising:

• a display system comprising:
• a display comprising a plurality of display pixels;
• a display synchronization signal device configured to emit light, wherein the display synchronization signal device is operable between at least a first state and a second state;
• and
• a display circuit configured to:
• receive data for a plurality of images, wherein the plurality of images comprises a first image and a second image,
• control the display to successively display the first image and then the second image with the display pixels, and
• control the display synchronization signal device to be in the first state when the first image is displayed by the display and to be in the second state when the second image is displayed by the display;
• and
• a camera system comprising:
• a digital camera disposed relative to the display such that the digital camera is operable to successively capture captured images of at least a portion of the display;
• a camera synchronization detector configured to detect the light from the display synchronization signal device;
• and
• a camera circuit configured to:
• control the camera synchronization detector to determine when the display synchronization signal device changes from the first state to the second state, and
• store or process one of the captured images in response to determining that the display synchronization signal device changed from the first state to the second state and, optionally, to control a camera synchronization signal device to emit signal light in response to storing or processing the one of the captured images.