SYSTEM AND METHOD OF CAPTURING LOW-LIGHT IMAGES ON A MOBILE DEVICE

• US 20120147243A1
• Filed: 12/13/2010
• Published: 06/14/2012
• Est. Priority Date: 12/13/2010
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Townsend, Graham Charles, Foster, Brett
• Granted Patent: US 8,379,123 B2
• Time in Patent Office: Days
• US Class Current: 348/333.02
• CPC Class Codes: H04N 2209/047 using multispectral pick-up elements
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths

Abstract

A system and method of capturing low-light images on a mobile device include a camera module, an image sensor, an infrared filter, and a visible light filter. The image sensor can detect a color spectrum of ambient light passed through a lens of the camera module. The visible light filter can cover a first portion of the image sensor, and the infrared filter can cover a second portion of the image sensor. A processor can be coupled to the image sensor to receive visible light data and infrared data. Visible light data can be formed from ambient light passed through the visible light filter and image sensor. Infrared data can formed from ambient light passed through the infrared filter and the image sensor. The visible light data and the infrared data are combined to form a low-light image data having enhanced brightness while maintaining color accuracy.

Claims

1. A mobile device comprising:

a camera module;

an image sensor adapted to detect a color spectrum of ambient light passed into the camera module;

an infrared filter coupled to the image sensor;

a visible light filter coupled to the image sensor;

a processing module coupled to the image sensor, the visible light filter, and the infrared filter, wherein the processing module is adapted to receive color spectrum data from the image sensor comprising infrared data and visible light data, said infrared data comprising ambient light passed into the camera module and filtered through the infrared filter, and said visible light data comprising ambient light passed into the camera module and filtered through the visible light filter; and

a display coupled to the processing module and adapted to display the color spectrum data.

2. The mobile device of claim 1, wherein the infrared filter covers a first portion of the image sensor and the visible light filter covers a second portion of the image sensor.

3. The mobile device of claim 2, wherein the first portion is approximately one-half of the image sensor and the second portion is approximately one-half of the image sensor.

4. The mobile device of claim 1, wherein the image sensor comprises a plurality of photosensors, each photosensor being responsive to ambient light filtered through at least one of the infrared filter and the visible light filter.

5. The mobile device of claim 4, wherein the infrared filter is an array of infrared photosensor filters, and each infrared photosensor filter covers one of the plurality of photosensors of the image sensor.

6. The mobile device of claim 4, wherein the visible light filter is an array of visible light photosensor filters, and each visible light photosensor filter covers one of the plurality of photosensors of the image sensor.

7. The mobile device of claim 1, wherein the infrared filter and the visible light filter form a filter array comprising a plurality of infrared photosensor filters and a plurality of visible light photosensor filters.

8. The mobile device of claim 7, wherein the visible light photosensor filters and the infrared photosensor filters are arranged on the image sensor such that at least some of the visible light photosensor filters are adjacent to an infrared photosensor filter and some of the visible light photosensor filters are adjacent to another visible light photosensor filter.

9. The mobile device of claim 1, wherein at least one of the visible light filter and the infrared filter is positioned on a rear surface of the image sensor.

10. The mobile device of claim 1, wherein at least one of the visible light filter and the infrared filter is position on a front surface of the image sensor.

11. The mobile device of claim 1, wherein the visible light filter is adapted to filter at least one of a red color, a green color, a blue color, and a yellow color from the color spectrum of ambient light passed into the camera module.

12. The mobile device of claim 1, wherein the image sensor is a single image sensor coupled to both the infrared filter and the visible light filter.

13. The mobile communication device of claim 1, wherein the infrared filter and the visible light filter are positioned between the lens and the image sensor.

14. A camera module for a mobile device, the camera module comprising:

a lens;

an image sensor adapted to detect a color spectrum of ambient light passed into the lens;

an infrared filter coupled to the image sensor; and

a visible light filter coupled to the image sensor;

wherein the image sensor, the visible light filter, and the infrared filter are configured to be communicatively coupled to a processor module adapted to;

receive color spectrum data from the image sensor comprising infrared data and visible light data, said infrared data comprising ambient light passed into the lens and filtered through the infrared filter and said visible light data comprising ambient light passed into the lens and filtered through the visible light filter; and

display the color spectrum data on a display of the mobile device.

15. The camera module of claim 14, wherein the infrared filter covers a first portion of the image sensor and the visible light filter covers a second portion of the image sensor.

16. The camera module of claim 14, wherein:

the image sensor comprises a plurality of photosensors, each photosensor being receptive to at least one of the infrared filter and the visible light filter;

the infrared filter is an array of infrared photosensor filters, each infrared photosensor filter covering one of the plurality of photosensors of the image sensor; and

the visible light filter is an array of visible light photosensor filters, each visible light photosensor filter covering one of the plurality of photosensors of the image sensor not covered by one of the infrared photosensor filters.

17. A method for generating a low-light image, the method comprising:

receiving ambient light from a camera module;

filtering the ambient light to receive infrared image data and visible light image data from a single image sensor of the camera module;

combining the infrared image data and the visible light image data to result in the low-light image.

18. The method of claim 17, wherein filtering the ambient light comprises placing an infrared filter over a first portion of the single image sensor and a visible light filter over the second portion of the single image sensor.

19. The method of claim 17, wherein filtering the ambient light comprises:

filtering a first portion of photosensors of the image sensor with an array of infrared photosensor filters; and

filtering a second portion of photosensors of the image sensor with an array of visible light photosensor filters.

20. The method of claim 17, wherein:

filtering ambient light data comprises placing an infrared filter and a visible light filter over the single image sensor; and

said image sensor comprises an array of infrared responders and visible light responders, said infrared responders adapted to receive infrared image data from the ambient light filtered by the infrared filter, and said visible light responders adapted to receive visible light image data from the ambient light filtered by the invisible light filter.