Display illumination with light-based touch sensing

A device comprising:

• a display having a first side, a second side opposite the first side, and a display surface extending from the first side to the second side;
• at least one light sensor;
• at least one light source operable to emit a first type of light to radiate over the display for detection by the at least one light sensor;
• the at least one light source operable to emit a second type of light to illuminate the display surface, at least in part, with visible light;
• and
• a diffuser extending over at least a portion of the display surface, the diffuser including a first end proximate the first side of the display and a second end, opposite the first end, proximate the second side of the display, the diffuser configured to:
• receive the second type of light at the first end,
• direct at least a portion of the second type of light received at the first end to a location of the diffuser proximate the second end, and
• direct the at least a portion of the second type of light to impinge upon the display,
• the diffuser further including a top surface, and a bottom surface opposite the top surface and facing the display surface of the display, the diffuser being positioned such that, when the first type of light radiates over the display, the diffuser is disposed between the display surface and the first type of light radiating over the display,
• wherein the display comprises a bi-stable display, the diffuser being configured to:
• direct the at least a portion of the second type of light to exit the bottom surface of the diffuser,
• receive, via the bottom surface, an amount of the second type of light reflected off of the display surface of the display, and
• direct the amount of the second type of light to exit the top surface of the diffuser.

A method comprising:

• causing a light source to emit a first type of light into a first light passage of a first light guide, the first type of light exiting a second passage of the first light guide, passing across a display surface of a display for detection by at least one light sensor to provide touch sensing in association with the display, the display having a first side and a second side opposite the first side, the display surface extending from the first side to the second side;
• receiving an input from the light sensor indicative of a sensed display touch;
• selectively causing the light source to emit a second type of light, different from the first type of light, to illuminate the display surface, at least in part, with visible light;
• directing the second type of light to exit the second passage of the first light guide and to enter a first end of a diffuser, the diffuser extending over at least a portion of the display surface and including a first end adjacent the second light passage of the first light guide, and a second end, opposite the first end, proximate the second side of the display;
• directing at least a portion of the second type of light entering the first end to a location of the diffuser proximate the second end, and
• directing the at least a portion of the second type of light to impinge upon the display,
• the diffuser further including a top surface, and a bottom surface opposite the top surface and facing the display surface of the display, the diffuser being positioned such that, when the first type of light radiates over the display, the diffuser is disposed between the display surface and the first type of light radiating over the display,
• wherein the display comprises a bi-stable display, the diffuser being configured to:
• direct the at least a portion of the second type of light to exit the bottom surface of the diffuser,
• receive, via the bottom surface, an amount of the second type of light reflected off of the display surface of the display, and
• direct the amount of the second type of light to exit the top surface of the diffuser.

A device comprising:

• a display having a display surface;
• at least one light sensor;
• a first light emitting diode (LED) operable to emit infrared light;
• a second LED operable to emit visible light;
• a light guide positioned at a first side of the display, the light guide having a first light passage positioned to receive the infrared light from the first LED and the visible light from the second LED, the light guide having a second light passage positioned at least partially above the display surface to emit the infrared light to pass across the display surface to a second side of the display for detection by the at least one light sensor to provide touch sensing in association with the display, the second light passage further positioned to emit the visible light to illuminate the display, at least in part, with visible light;
• and
• a diffuser extending over at least a portion of the display surface, the diffuser including a first end adjacent the second light passage and a second end, opposite the first end, proximate the second side of the display, the diffuser configured to:
• receive the visible light, from the second light passage, at the first end,
• direct at least a portion of the visible light received at the first end to a location of the diffuser proximate the second end, and
• direct the at least a portion of the visible light to impinge upon the display,
• the diffuser further including a top surface, and a bottom surface opposite the top surface and facing the display surface of the display, the diffuser being positioned such that, when the first type of light radiates over the display, the diffuser is disposed between the display surface and the first type of light radiating over the display,
• wherein the display comprises a bi-stable display, the diffuser being configured to:
• direct the at least a portion of the second type of light to exit the bottom surface of the diffuser,
• receive, via the bottom surface, an amount of the second type of light reflected off of the display surface of the display, and
• direct the amount of the second type of light to exit the top surface of the diffuser.