Sensing system for detection of light incident to a light emitting layer of an electronic device display
Systems and methods for detection of incident light are described. An optical imaging sensor is positioned at least partially within an active display area of a display and is configured to detect and characterize one or more properties of light incident to the active display area of the display.
1. An electronic device comprising:
a housing defining an internal volume;
a biometric imaging sensor comprising:
an array of light sensors each configured to detect infrared light; and
a controller conductively coupled to each light sensor of the array of light sensors via a respective dedicated signal path; and
a display disposed within the internal volume and comprising:
a substrate; and
an array of pixels defined on the substrate and separated by interpixel regions; wherein:
each light sensor of the array of light sensors is formed onto the substrate within the interpixel regions, coplanar with the array of pixels, and configured to receive infrared light emitted from the array of pixels that reflects from a surface of a user's finger touching the display.
2. The electronic device of claim 1 , wherein the controller is configured to generate an image of a fingerprint of the user's finger in response to receiving output from the array of light sensors.
3. The electronic device of claim 1 , wherein each light sensor comprises an organic solar cell.
4. The electronic device of claim 1 , wherein the controller is communicably coupled to a processor of the electronic device.
5. The electronic device of claim 1 , wherein each light sensor shares a border with a pixel of the array of pixels.
6. The electronic device of claim 1 , wherein the array of light sensors is configured to receive light during an off period of a duty cycle of the array of pixels.
7. The electronic device of claim 1 , wherein the display is a micro light emitting diode display.
8. The electronic device of claim 1 , wherein each light sensor of the array of light sensors comprises a photodiode.
9. An electronic device comprising:
a housing defining an internal volume;
a display disposed within the internal volume and comprising:
a substrate; and
an array of pixels formed in a pattern on the substrate and separated by interpixel regions, thereby defining interpixel regions; and
an optical fingerprint sensor comprising:
an array of infrared photodiodes, each infrared photodiode of the array formed onto interpixel regions of the substrate of the display, sharing a border with at least one pixel of the array of pixels, and configured to receive infrared light incident to the display; and
a controller conductively coupled to each infrared photodiode of the array of photodiodes via a respective dedicated circuit.
10. The electronic device of claim 9 , wherein at least one dedicated circuit trace is formed onto the substrate.
11. The electronic device of claim 9 , wherein at least one dedicated circuit trace is formed onto interpixel regions of the substrate.
12. The electronic device of claim 9 , wherein the controller is configured to generate an image of a fingerprint of a user touching the display.
13. The electronic device of claim 9 , wherein the optical fingerprint sensor is configured to operate only during an off period of a duty cycle of the display.
14. A method of imaging a surface of a display of an electronic device, the method comprising:
detecting a touch input to a display with a touch input sensor aligned with the display;
selecting a set of light-emitting elements based on a location of the touch input;
selecting a set of infrared light sensors defined within interpixel regions separating pixels of the selected set of light-emitting elements, each infrared light sensor coupled to a controller via a dedicated signal path;
illuminating the selected set of light-emitting elements at a selected duty cycle;
operate the selected set of light sensors during an off period of a duty cycle of the display;
determine magnitude of light received by the selected set of light sensors; and
assemble a two-dimensional image based on the received light.
15. The method of claim 14 , wherein the two-dimensional image is a fingerprint image of the touch input.