Proximity detection using multiple inputs
In one embodiment, a method includes determining, by a capacitive touch sensor of a device, a presence of an object; activating an optical sensor of the device in response to determining the presence of the object; and determining, by the optical sensor of the device, a touch or proximity input within a proximity-sensing volume.
1. A method comprising:
determining, by a capacitive sensor of a device, a presence of a physical object;
activating one or more emitters of an optical sensor of the device in response to determining the presence of the physical object, wherein the optical sensor is operable to toggle, based on data received from the capacitive sensor, between an activated state and a deactivated state;
determining, by the optical sensor of the device, a touch or proximity input within a proximity-sensing volume of the device, the touch or proximity caused by the physical object; and
distinguishing a type of the physical object based on a signal strength from the capacitive sensor and a signal strength from the optical sensor, wherein the capacitive sensor is a capacitive touch sensor.
2. The method of claim 1 , wherein the optical sensor is sensitive to radiation with wavelength substantially within an infrared (IR) portion of the electromagnetic spectrum.
3. The method of claim 1 , wherein the optical sensor is located such that an area of coverage of the optical sensor overlaps at least a portion of a capacitive proximity-sensing volume.
4. The method of claim 1 , further comprising:
determining a direction of motion of the physical object within the proximity-sensing volume of the device; and
initiating a pre-determined function of the device based on the direction of motion.
5. The method of claim 1 , further comprising deactivating the optical sensor in response to the optical sensor determining the physical object is no longer present.
6. The method of claim 1 , further comprising verifying the presence of the physical object through the optical sensor.
7. The method of claim 1 , wherein:
the capacitive sensor is configured to detect presence of the physical object with a higher sensitivity than the optical sensor; and
the method further comprises:
accepting the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor exceeds a threshold; and
rejecting the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor falls below the threshold.
8. A computer-readable non-transitory storage medium embodying logic configured when executed to:
determine, by a capacitive sensor of a device, a presence of a physical object, the capacitive sensor being a capacitive touch sensor;
activate one or more emitters of an optical sensor of the device in response to determining the presence of the physical object, wherein the optical sensor is operable to toggle, based on data received from the capacitive sensor, between an activated state and a deactivated state;
determine, by the optical sensor of the device, a touch or proximity input within a proximity-sensing volume of the device, the touch or proximity caused by the physical object; and
distinguish, based on a signal strength from the capacitive sensor and a signal strength from the optical sensor, a type of the physical object.
9. The medium of claim 8 , wherein the optical sensor is sensitive to radiation with wavelength substantially within an infrared (IR) portion of the electromagnetic spectrum.
10. The medium of claim 8 , wherein the optical sensor is located such that an area of coverage of the optical sensor overlaps at least a portion of a capacitive proximity-sensing volume.
11. The medium of claim 8 , wherein the logic is further configured to:
determine a direction of motion of the physical object within the proximity-sensing volume of the device; and
initiate a pre-determined function of the device based on the direction of motion.
12. The medium of claim 8 , wherein the logic is further configured to deactivate the optical sensor in response to the optical sensor determining the physical object is no longer present.
13. The medium of claim 8 , wherein the logic is further configured to verify the presence of the physical object through the optical sensor.
14. The medium of claim 8 , wherein:
the capacitive sensor is configured to detect presence of the physical object with a higher sensitivity than the optical sensor; and
the logic is further configured to:
accept the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor exceeds a threshold; and
reject the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor falls below the threshold.
15. A device comprising:
a capacitive sensor having a capacitive proximity-sensing volume, the capacitive sensor being a capacitive touch sensor;
an optical sensor; and
a computer-readable non-transitory storage media coupled to the capacitive touch sensor and the optical sensor and embodying logic configured when executed to:
determine a presence of a physical object;
activate one or more emitters of the optical sensor in response to determining the presence of the physical object, wherein the optical sensor is operable to toggle, based on data received from the capacitive sensor, between an activated state and a deactivated state;
determine a touch or proximity input within a proximity-sensing volume of the device through the optical sensor, the touch or proximity caused by the physical object; and
distinguish, based on a signal strength from the capacitive sensor and a signal strength from the optical sensor, a type of the physical object.
16. The device of claim 15 , wherein the logic is further configured to:
determine a direction of motion of the physical object within the proximity-sensing volume of the device; and
initiate a pre-determined function of the device based on the direction of motion.
17. The device of claim 15 , wherein the optical sensor is located such that an area of coverage of the optical sensor overlaps at least a portion of the capacitive proximity-sensing volume.
18. The device of claim 15 , wherein the logic is further configured to deactivate the optical sensor in response to the optical sensor determining the physical object is no longer present.
19. The device of claim 15 , wherein the logic is further configured to verify the presence of the physical object through the optical sensor.
20. The device of claim 15 , wherein:
the capacitive sensor is configured to detect presence of the physical object with a higher sensitivity than the optical sensor; and
the logic is further configured to:
accept the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor exceeds a threshold; and
reject the presence of the physical object when a signal due to the determined touch or proximity input determined by the optical sensor falls below the threshold.