Computing device user presence detection

• US 8,884,896 B2
• Filed: 01/18/2012
• Issued: 11/11/2014
• Est. Priority Date: 01/18/2012
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Tabone, Ryan, Staaf, Anton Valdemar
• Primary Examiner(s): GIESY, ADAM
• Application Number:
  US13/352,918
• Publication Number:
  US 20130181936A1
• Time in Patent Office: 1,028 Days
• Field of Search: None
• US Class Current: 345/173
• CPC Class Codes: G06F 1/3231 Monitoring the presence, absence or movement of users
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A computing device may detect the presence of a user after the user has not interacted with the computing device for a predetermined time period. The user may leave the device powered up, but after the predetermined time period has expired, the device enters a user detection mode from a normal operation mode such that nonessential components are powered down. A trackpad may be used to detect the presence of the user in the user detection mode. An electric field is generated by conductive plates of the trackpad. When the user extends his hand over the trackpad, sense lines in the track pad detect the interference with the electric field caused by the hand. A processor is signaled to return the device normal operation mode and restore full power to the device. A camera may be also used to detect the user'"'"'s presence during the user detection mode.

Claims

1. A computing device comprising:

a plurality of computing device components;

a trackpad comprising a plurality of conductive plates; and

a processor configured to;

provide reduced power to at least some of the computing device components and provide increased power to the trackpad in response to a lack of user interaction with the computing device for a predetermined time period such that an overall power consumption by the computing device is decreased,

activate the plurality of conductive plates of the trackpad to cause generation of an electric field over the trackpad using the increased power to the trackpad, and

provide normal operating power to the at least some of the computing device components and to the trackpad in response to an object entering the electric field over the trackpad without the object touching the trackpad.

2. The computing device of claim 1, wherein the object comprises the user'"'"'s hand.

3. The computing device of claim 1, wherein the processor provides reduced power to the at least some of the computing device components by causing a power supply to reduce power provided to the at least some of the computing device components.

4. The computing device of claim 1, wherein the processor detects when an object enters the electric field in response to the object interrupting the electric field.

5. The computing device of claim 1, wherein the trackpad further comprises a plurality of sense lines coupled to the conductive plates, the interruption of the electric field by the object being detected by the sense lines.

6. The computing device of claim 5, wherein sense lines detect the interruption of the electric field by the object by detecting a change in a dielectric constant over the trackpad.

7. The computing device of claim 5, wherein, in response to detecting the interruption of the electric field by the object, the sense lines cause a signal to be forwarded to the processor indicating that the object interrupted the electric field.

8. The computing device of claim 1, wherein the trackpad further comprises a plurality of drive lines coupled to the conductive plates, the drive lines generating the electric field.

9. The computing device of claim 1, wherein the conductive plates are activated by connecting at least some of the plurality of the conductive plates in parallel such that the at least some of the conductive plates behave as a capacitive sensor.

10. The computing device of claim 9, wherein the at least some of the conductive plates are connected such that the trackpad behaves as a single conductive plate, the electric field emanating outwardly from the trackpad.

11. The computing device of claim 9, wherein the at least some of the conductive plates are connected such that a first portion of the trackpad behaves as a positive capacitive sensor and a second portion of the trackpad behaves as a negative capacitive sensor, the electric filed emanating between the first portion and the second portion of the trackpad.

12. A computer-implemented method that when executed by a processor causes the processor to perform steps of the method, the steps comprising:

in normal operation mode, determining that a user has not interacted with a computing device for a predetermined time period;

responsive to determining that the user has not interacted with the computing device for the predetermined time period, causing the computing device to enter user detection mode, wherein at least some components of the computing device are provided with reduced power in the user detection mode and a trackpad of the computing device is provided with increased power in the user detection mode such that an overall power consumption of the computing device is decreased in the user detection mode;

responsive to entering the user detection mode, activating a plurality of conductive plates of the trackpad to cause generation of an electric field over the trackpad;

detecting a presence of the user proximate the computing device using the trackpad in the user detection mode, wherein the presence of the user is detected without the user touching the computing device; and

causing the computing device to enter normal operation mode in response to the detection of the presence of the user, wherein the at least some of the computing device components and the trackpad are provided with normal operating power in the normal operation mode.

13. The method of claim 12, wherein the presence of the user is detected in response to an object interrupting the electric field and the trackpad detecting a change in a dielectric constant over the trackpad caused by the object.

14. The method of claim 12, wherein activating the plurality of the conductive plates of the trackpad comprises connecting at least some of the plurality of the conductive plates in parallel such that the at least some of the conductive plates behave as a capacitive sensor.

15. The method of claim 14, wherein the at least some of the conductive plates are connected such that the trackpad behaves as a single conductive plate, the electric field emanating outwardly from the trackpad.

16. The method of claim 14, wherein the at least some of the conductive plates are connected such that a first portion of the trackpad behaves as a positive capacitive sensor and a second portion of the trackpad behaves as a negative capacitive sensor, the electric filed emanating between the first portion and the second portion of the trackpad.

17. A non-transitory computer readable storage medium comprising instructions, that when executed by a processor, cause the processor to perform a method comprising:

in normal operation mode, determining that a user has not interacted with a computing device for a predetermined time period;

responsive to determining that the user has not interacted with the computing device for the predetermined time period, causing the computing device to enter user detection mode, wherein at least some components of the computing device are provided with reduced power in the user detection mode and a trackpad of the computing device is provided with increased power in the user detection mode such that an overall power consumption of the computing device is decreased in the user detection mode;

responsive to entering the user detection mode, activating a plurality of conductive plates of the trackpad to cause generation of an electric field over the trackpad;

detecting a presence of the user proximate the computing device using the trackpad in the user detection mode, wherein the presence of the user is detected without the user touching the computing device; and

causing the computing device to enter normal operation mode in response to the detection of the presence of the user, wherein the at least some of the computing device components and the trackpad are provided with normal operating power in the normal operation mode.

18. The computer readable storage medium of claim 17, wherein the presence of the user is detected in response to an object interrupting the electric field and the trackpad detecting a change in a dielectric constant over the trackpad caused by the object.

19. The computer readable storage medium of claim 17, wherein activating the plurality of the conductive plates of the trackpad comprises connecting at least some of the plurality of the conductive plates in parallel such that the at least some of the conductive plates behave as a capacitive sensor.

20. The computer readable storage medium of claim 19, wherein the at least some of the conductive plates are connected such that the trackpad behaves as a single conductive plate, the electric field emanating outwardly from the trackpad.

21. The computer readable storage medium of claim 19, wherein the at least some of the conductive plates are connected such that a first portion of the trackpad behaves as a positive capacitive sensor and a second portion of the trackpad behaves as a negative capacitive sensor, the electric filed emanating between the first portion and the second portion of the trackpad.