INFRARED SENSOR INTEGRATED IN A TOUCH PANEL
First Claim
Patent Images
1. A touch panel system comprising:
- a touchable surface;
at least one infrared source integrated in the touch panel system and configured to direct infrared radiation towards and through the touchable surface for illuminating one or more objects that are in contact with or adjacent to the touchable surface with infrared radiation; and
an active matrix circuit comprising;
an infrared sensor that is sensitive to infrared radiation incident on the infrared sensor which is directed by the at least one infrared source towards and through the touchable surface and reflected from above the touchable surface by the one or more objects;
a capacitor interconnected to the infrared sensor; and
a readout transistor interconnected to the infrared sensor and the capacitor, wherein a voltage imposed on the capacitor discharges through the infrared sensor if infrared radiation is incident on the infrared sensor, a charge to reset the voltage on the capacitor flows through the readout transistor, and a measure of the infrared radiation incident on the infrared sensor is output based on the charge needed to reset the voltage on the capacitor.
1 Assignment
0 Petitions
Accused Products
Abstract
An infrared source is configured to illuminate the underside of one or more objects on or above a touchable surface of a touch panel. Infrared light reflected from the underside of the object(s) is detected by an infrared sensor integrated in the touch panel below the touchable surface.
-
Citations
20 Claims
-
1. A touch panel system comprising:
-
a touchable surface; at least one infrared source integrated in the touch panel system and configured to direct infrared radiation towards and through the touchable surface for illuminating one or more objects that are in contact with or adjacent to the touchable surface with infrared radiation; and an active matrix circuit comprising; an infrared sensor that is sensitive to infrared radiation incident on the infrared sensor which is directed by the at least one infrared source towards and through the touchable surface and reflected from above the touchable surface by the one or more objects; a capacitor interconnected to the infrared sensor; and a readout transistor interconnected to the infrared sensor and the capacitor, wherein a voltage imposed on the capacitor discharges through the infrared sensor if infrared radiation is incident on the infrared sensor, a charge to reset the voltage on the capacitor flows through the readout transistor, and a measure of the infrared radiation incident on the infrared sensor is output based on the charge needed to reset the voltage on the capacitor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14)
-
-
8. The touch panel system of claim 8, wherein an anode of the infrared-sensitive photodiode is interconnected to a common bias line which is interconnected to a plurality of pixel circuits.
-
15. A touch panel system comprising:
-
a touchable surface; at least one infrared source integrated in the touch panel system and configured to direct infrared radiation towards and through the touchable surface for illuminating one or more objects that are in contact with or adjacent to the touchable surface with infrared radiation; and a display configured to display an image viewable via the touchable surface of the touch panel system, the display having an active matrix layer comprising; a set of select lines corresponding to pixels of the display; an infrared sensor that is sensitive to infrared radiation incident on the infrared sensor which is directed by the at least one infrared source towards and through the touchable surface and reflected from above the touchable surface by the one or more objects; a readout transistor interconnected to the infrared sensor, a select line, and a readout line; and a capacitor interconnected to the infrared sensor and the readout transistor, wherein a voltage imposed on the capacitor discharges through the infrared sensor if infrared radiation is incident on the infrared sensor, a charge to reset the voltage on the capacitor flows from the readout line through the readout transistor, and a measure of the infrared radiation incident on the infrared sensor is output based on the charge needed to reset the voltage on the capacitor. - View Dependent Claims (16, 17, 18)
-
-
19. A method performed in a touch panel system, the method comprising:
-
directing infrared radiation from at least one infrared source integrated in the touch panel system towards and through a touchable surface of the touch panel system for illuminating one or more objects that are in contact with or adjacent to the touchable surface with infrared radiation; detecting infrared radiation incident on the infrared sensor which is directed by the at least one infrared source towards and through the touchable surface and reflected from above the touchable surface by the one or more objects; discharging a voltage imposed on a capacitor through the infrared sensor if infrared radiation is incident on the infrared sensor; resetting the voltage on the capacitor; and outputting a measure of the infrared radiation incident on the infrared sensor based on the charge needed to reset the voltage on the capacitor. - View Dependent Claims (20)
-
Specification