Electronic device with color sensing ambient light sensor

Patent metadata

Field	Value
Publication number	US-10580341-B2
Application number	US-201514870924-A
Country	US
Kind code	B2
Filing date	Sep 30, 2015
Priority date	Feb 11, 2015
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

An electronic device may be provided with a display mounted in a housing. A color sensing ambient light sensor may measure the color of ambient light. The color sensing ambient light sensor may be mounted in alignment with an ambient light sensor window formed in an inactive area of the display. The color sensing ambient light sensor may be formed from detectors on a semiconductor substrate. The detectors may include detectors that have spectral sensitivity profiles matching those of color matching functions. The color sensing ambient light sensor may include an infrared light detector. Light redirecting structures such as a diffuser, prism film, negative lens film, or privacy film may be used in directing light into the ambient light sensor. The color sensing ambient light sensor may be calibrated by exposing the sensor to light sources of different types.

First claim

What is claimed is:

1. An electronic device that is exposed to ambient light that has an ambient light color, comprising:
an input-output device that receives input from a user;
a display that displays images for the user;
a housing in which the input-output device and the display are mounted;
control circuitry in the housing; and
a color sensing ambient light sensor in the housing with which the control circuitry measures an ambient light color, wherein the control circuitry adjusts the display at least partly based on the measured ambient light color, wherein the control circuitry is configured to identify a light source type associated with the ambient light based on sensor data from the color sensing ambient light sensor, to select a color converting matrix based on the identified light source type, and to apply the color converting matrix to the sensor data from the color sensing ambient light sensor to produce a color measurement associated with the sensor data from the color sensing ambient light sensor.

2. The electronic device defined in claim 1 wherein the color sensing ambient light sensor has at least five light detectors each having a respective spectral sensitivity profile.

3. The electronic device defined in claim 1 wherein the color sensing ambient light sensor has a semiconductor substrate and has at least five light detectors in the substrate each having a respective spectral sensitivity profile.

4. The electronic device defined in claim 3 wherein at least one of the spectral sensitivity profiles is a standard observer color matching function and at least one of the spectral sensitivity profiles is a visible light spectral sensitivity profile that is not a standard observer color matching function.

5. The electronic device defined in claim 3 wherein at least one of the spectral sensitivity profiles is within a 20% root-mean-square deviation from a standard observer color matching function disregarding wavelength differences between the at least one of the spectral sensitivity profiles and the standard observer color matching function.

6. The electronic device defined in claim 3 wherein one of the spectral sensitivity profiles matches a standard observer color matching function.

7. The electronic device defined in claim 6 wherein one of the spectral sensitivity profiles matches a z CIE standard observer color matching function and wherein one of the spectral sensitivity profiles matches a y CIE standard observer color matching function.

8. The electronic device defined in claim 3 wherein one of the spectral sensitivity profiles matches an upper half of an x CIE standard observer color matching function.

9. The electronic device defined in claim 8 wherein the color sensing ambient light sensor has fewer than seven visible light detectors.

10. The electronic device defined in claim 8 wherein a linear combination of two or more of the spectral sensitivity profiles matches a standard observer color matching function.

11. The electronic device defined in claim 10 wherein the color sensing ambient light sensor has fewer than seven visible light detectors.

12. The electronic device defined in claim 11 further comprising:
an ambient light sensor window in the display; and
a light redirection structure in the ambient light sensor window, wherein the color sensing ambient light sensor receives the ambient light through the ambient light sensor window and the light redirection structure.

13. The electronic device defined in claim 12 further comprising ink in the ambient light sensor window.

14. The electronic device defined in claim 12 wherein the light redirection structure comprises a structure selected from the group consisting of: a diffuser film, a prism film, a privacy film, and a negative lens film.

15. The electronic device defined in claim 12 wherein the light redirection structure comprises a diffuser having a Lambertian scattering profile.

16. The electronic device defined in claim 12 wherein the light redirection structure comprises a diffuser having a scattering profile that differs at any angle of light incidence on the diffuser by less than 20% from a Lambertian scattering profile at that angle of light incidence.

17. The electronic device defined in claim 1 wherein the electronic device is selected from the group consisting of: a portable computer, a tablet computer, a cellular telephone, and a wrist-watch device.

18. The electronic device defined in claim 1 wherein the color sensing ambient light sensor has light detectors each having a respective spectral sensitivity profile.

19. The electronic device defined in claim 18 wherein the light detectors are arranged in a common-centric layout.

20. The electronic device defined in claim 19 wherein the common-centric layout exhibits four-fold symmetry.

21. The electronic device defined in claim 19 wherein the common-centric layout exhibits two-fold symmetry.

22. The electronic device defined in claim 18 wherein each of the light detectors comprises at least a first portion and a second portion on opposing sides of a central point.

23. The electronic device defined in claim 18 wherein each of the light detectors has a first portion and a second portion to reduce angular sensitivity for the color sensing ambient light sensor.

24. The electronic device defined in claim 1 wherein the control circuitry adjusts the display based directly on the produced color measurement.

25. A method for using a color sensing ambient light sensor, comprising:
calibrating the color sensing ambient light sensor, wherein calibrating the color sensing ambient light sensor comprises:
for each of a plurality of ambient light source lighting types, measuring color coordinates for each of multiple ambient light sources with a reference spectrometer and gathering sensor data from the color sensing ambient light sensor while the color sensing ambient light sensor is exposed to ambient light from each of the multiple ambient light sources of that ambient light source lighting type; and
processing the gathered sensor data and the measured color coordinates to produce a plurality of color converting matrices, each color converting matrix corresponding to a respective one of the plurality of ambient light source lighting types;

gathering additional sensor data with the color sensing ambient light sensor; and
with control circuitry, identifying a light source type associated with received ambient light based on the additional sensor data.

26. The method defined in claim 25 wherein processing the gathered sensor data and the measured color coordinates comprises multiplying a color coordinate matrix that contains the measured color coordinates and a pseudoinverse of a sensor spectral response matrix associated with the color sensing ambient light sensor.

27. A color sensing ambient light sensor for a portable electronic device having a display with a color that is adjusted based on color measurements from the color sensing ambient light sensor, comprising:
a semiconductor substrate;
at least five visible light detectors in the semiconductor substrate, each having a different spectral sensitivity profile, wherein at least one of the five visible light detectors has a spectral sensitivity profile that matches a standard observer color matching function and wherein at least one of the five visible light detectors ha

Assignees

• Apple Inc

Inventors

• Jia Zhang
• Erickson Christopher S

Classifications

• G01J3/0216

  using light concentrators or collectors or condensers · CPC title

• G01J3/465

  taking into account the colour perception of the eye; using tristimulus detection · CPC title

• G01J3/0205

  Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows · CPC title

• G01J1/32

  adapted for automatic variation of the measured or reference value (regulation of light intensity G05D25/00) · CPC title

• G01J3/513 Primary

  having fixed filter-detector pairs · CPC title