Backlight compensation for a computing device with two or more display devices
In some implementations, a computing device may include a first display device and a second display device. An embedded controller may determine a first perceived brightness of the first display based on a first current and a first amount of ambient light associated with the first display device, determine a second perceived brightness of the second display device based on a second current and a second amount of ambient light associated with the second display device, and determine a ratio of the first perceived brightness to the second perceived brightness. The embedded controller may modify, based at least in part on the ratio, the second current to create a second modified amount of current associated with the second display device that modifies the second perceived brightness of the second display device to create a modified second perceived brightness of the second display device.
1. A method comprising:
determining, by a computing device comprising a first display device and a second display device, a first perceived brightness associated with the first display device based on a first current and a first amount of ambient light associated with the first display device;
determining, by the computing device, a second perceived brightness associated with the second display device based on a second current and a second amount of ambient light associated with the second display device;
determining, by the computing device, a first ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device;
modifying, by the computing device and based at least in part on the first ratio, the second current to create a second modified amount of current associated with the second display device, wherein the second modified amount of current modifies the second perceived brightness of the second display device to create a modified second perceived brightness of the second display device; and
determining a second ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device.
2. The method of claim 1 , further comprising:
determining, using a first ambient light sensor, the first amount of ambient light associated with the first display device; and
determining, using a second ambient light sensor, the second amount of ambient light associated with the second display device.
3. The method of claim 1 , further comprising:
determining that the second ratio differs from a target ratio by less than a predetermined amount.
4. The method of claim 1 , further comprising:
determining that the second ratio differs from a target ratio by at least a predetermined amount; and
modifying the second modified amount of current to create a third modified amount of current.
5. The method of claim 1 , wherein modifying the second current to create the second modified amount of current comprises:
modifying a duty cycle of a square wave providing power to a backlight of the first display device.
6. The method of claim 1 , wherein:
increasing the second current to create the second modified amount of current increases the second perceived brightness of the second display device.
7. The method of claim 1 , wherein:
decreasing the second current to create the second modified amount of current decreases the second perceived brightness of the second display device.
8. A computing device comprising:
a first display device;
a second display device;
an embedded controller configured with logic instructions to perform operations comprising:
determining a first perceived brightness associated with the first display device based on a first current and a first amount of ambient light associated with the first display device;
determining a second perceived brightness associated with the second display device based on a second current and a second amount of ambient light associated with the second display device;
determining a first ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device;
modifying, based at least in part on the first ratio, the second current to create a second modified amount of current associated with the second display device, wherein the second modified amount of current modifies the second perceived brightness of the second display device to create a modified second perceived brightness of the second display device; and
determining a second ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device.
9. The computing device of claim 8 , further comprising:
a first ambient light sensor to measure the first amount of ambient light associated with the first display device; and
a second ambient light sensor to measure the second amount of ambient light associated with the second display device.
10. The computing device of claim 8 , further comprising:
a first backlight driver circuit to provide the first current to a first set of light emitting diodes (LEDs) associated with the first display device; and
a second backlight driver circuit to provide the second current to a second set of light emitting diodes (LEDs) associated with the second display device.
11. The computing device of claim 8 , further comprising:
a first set of temperature sensors to determine a first temperature associated with the first display device; and
a second set of temperature sensors to determine a second temperature associated with the second display device.
12. The computing device of claim 11 , the operations further comprising:
determining the first ratio based at least in part on the first temperature and the second temperature.
13. The computing device of claim 8 , wherein the operations further comprise:
determining that the second ratio differs from a target ratio by at least a predetermined amount; and
modifying the second modified amount of current to create a third modified amount of current.
14. An embedded controller configured with logic instructions to perform operations comprising:
determining, for a computing device comprising a first display device and a second display device, a first perceived brightness associated with the first display device based on a first current and a first amount of ambient light associated with the first display device;
determining a second perceived brightness associated with the second display device based on a second current and a second amount of ambient light associated with the second display device;
determining a first ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device;
modifying based at least in part on the first ratio, the second current to create a second modified amount of current associated with the second display device, wherein the second modified amount of current modifies the second perceived brightness of the second display device to create a modified second perceived brightness of the second display device; and
determining a second ratio of the first perceived brightness of the first display device to the second perceived brightness of the second display device.
15. The embedded controller of claim 14 wherein the first ratio is determined based on:
the first current and the first amount of ambient light associated with the first display device; and
the second current and the second amount of ambient light associated with the second display device.
16. The embedded controller of claim 14 , the operations further comprising:
determining a third current associated with a third display device of the computing device;
determining a third ratio of the first perceived brightness of the first display device to a third perceived brightness of the third display device; and
modifying the third current to create a third modified amount of current.
17. The embedded controller of claim 14 , the operations further comprising:
determining that the second ratio differs from a target ratio by at least a predetermined amount; and
modifying the second modified amount of current to create a third modified amount of current.
18. The embedded controller of claim 14 , the operations further comprising:
determining, using a first brightness sensor, a first brightness associated with the first display device; and
determining, using a second brightness sensor, a second brightness associated with the second display device.
19. The embedded controller of claim 14 , the operations further comprising:
determining an orientation of the computing device; and
determining a display mode of the computing device.
20. The embedded controller of claim 14 , the operations further comprising:
sending an instruction from the embedded controller to a backlight driver associated with the second display device to create the second modified amount of current, wherein the instruction is sent via an inter-integrated circuit (I2C) bus.