Luminescence shock avoidance in display devices

• US 8,405,688 B2
• Filed: 11/23/2011
• Issued: 03/26/2013
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Pantfoerder, Kai Achim
• Primary Examiner(s): Caschera, Antonio A
• Application Number:
  US13/304,176
• Publication Number:
  US 20120068981A1
• Time in Patent Office: 489 Days
• Field of Search: None
• US Class Current: 345/690
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0653 Controlling or limiting the speed of brightness adjustment of the illumination source
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 5/10 Intensity circuits

Abstract

A luminescence shock avoidance algorithm selectively limits the brightness level of a display device when the display device is activated in a dark environment to prevent the temporary vision impairment that can occur when a display device is activated in a dark environment. The algorithm receives the state of the display (e.g. on or in standby mode), and can optionally receive an ambient lighting value from an ambient light sensor and a user-selectable manual brightness adjustment setting to determine whether luminescence shock avoidance should even be triggered, and if it is triggered, how much should the brightness level of the display be limited.

Claims

1. A method, comprising:

detecting a triggering activity;

with a sensor, detecting a current ambient light level at a display device when the triggering activity is detected;

adjusting a brightness of the display device from a zero brightness level to a first brightness level when the current ambient light level is below a threshold; and

adjusting the brightness of the display device from the zero brightness level to a second brightness level when the current ambient light level meets or exceeds the threshold.

2. The method of claim 1, further comprising adjusting the first or second brightness levels using a display brightness control.

3. The method of claim 1 wherein the threshold comprises a luminescence shock threshold and wherein the second brightness level is greater than the first brightness level.

4. The method defined in claim 1 further comprising:

after a predetermined time interval has elapsed from the triggering activity, changing the brightness of the display device from the first brightness level to the second brightness level.

5. The method of claim 4, wherein changing the brightness of the display device from the first brightness level to the second brightness level comprises ramping up the brightness of the display device from the first brightness level to the second brightness level.

6. A non-transitory computer-readable storage medium comprising program code for causing performance of a method comprising:

detecting a triggering activity;

detecting a current ambient light level at a display device when the triggering activity is detected;

activating the display device such that the display device has, at least when initially activated, a first brightness level when the current ambient light level is below a threshold; and

activating the display device such that the display device has, at least when initially activated, a second brightness level when the current ambient light level meets or exceeds the threshold.

7. The non-transitory computer-readable storage medium of claim 6, further comprising adjusting the first or second brightness levels using a display brightness control.

8. The non-transitory computer-readable storage medium of claim 6 wherein the threshold comprises a luminescence shock threshold and wherein the second brightness level is greater than the first brightness level.

9. The non-transitory computer-readable storage medium of claim 6 further comprising:

after a predetermined time interval has elapsed from the triggering activity, changing the brightness of the display device from the first brightness level to the second brightness level.

10. The non-transitory computer-readable storage medium of claim 9, wherein changing the brightness of the display device from the first brightness level to the second brightness level comprises ramping up the brightness of the display device from the first brightness level to the second brightness level.

11. A system for avoiding luminescence shock in a display device when the display device is illuminated, comprising:

a display device; and

a processor coupled to the display device and capable of

detecting a triggering activity in the display device;

detecting a current ambient light level at the display device when the triggering activity is detected;

adjusting a brightness of the display device from a zero brightness level to a first brightness level when the current ambient light level is below a luminescence shock threshold; and

adjusting the brightness of the display device from the zero brightness level to a second brightness level when the current ambient light level meets or exceeds the luminescence shock threshold.

12. The system of claim 11, the processor further programmed for adjusting the first or second brightness levels using a display brightness control.

13. The system of claim 11, the system incorporated into a computing device.

14. The system of claim 11 wherein the second brightness level is greater than the first brightness level.

15. The system of claim 11, the processor further programmed for, after a predetermined time interval has elapsed from the triggering activity, changing the brightness of the display device from the first brightness level to the second brightness level.

16. The system of claim 15, the processor further programmed for changing the brightness of the display device from the first brightness level to the second brightness level by ramping up the brightness of the display device from the first brightness level to the second brightness level.

17. A computing device, comprising:

a display device; and

a processor coupled to the display device and capable of

detecting a triggering activity in the display device;

detecting a current ambient light level at the display device when the triggering activity is detected;

adjusting a brightness of the display device from a zero brightness level to a first brightness level when the current ambient light level is below a luminescence shock threshold; and

adjusting the brightness of the display device from the zero brightness level to a second brightness level greater from the first brightness level when the current ambient light level meets or exceeds the luminescence shock threshold.