Electronic camera with dual resolution sensors

• US 5,926,218 A
• Filed: 06/04/1996
• Issued: 07/20/1999
• Est. Priority Date: 06/04/1996
• Status: Expired due to Term

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Smith, Stephen P.
• Primary Examiner(s): Ho, Tuan V.
• Application Number:
  US08/658,973
• Time in Patent Office: 1,141 Days
• Field of Search: 348/207, 348/64, 348/231, 348/240, 348/333, 348/335, 348/344, 348/358, 348/42, 348/47
• US Class Current: 348/207.99
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof

Abstract

An electronic camera includes a low resolution image sensor responsive to image light for generating a low resolution output signal that is used for camera control functions, such as image viewing, and a high resolution image sensor responsive to image light for generating a high resolution output signal that is used to produce an output image signal. The camera further includes an electronic display driven by the output signal from the low resolution image sensor, a zoom lens for varying the size of the image incident upon the high resolution image sensor and a zoom interpolator responsive to a zoom setting of the zoom lens. The output signal from the low resolution image sensor is then applied to the zoom interpolator, which processes the output signal so that the size of a display image obtained from the low resolution signal corresponds to the zoom setting of the zoom lens.

Claims

1. An electronic camera for capturing and processing data relating to an image in order to produce an output image signal, said camera comprising:

a first image sensor responsive to image light for generating a first output signal that is used for camera control functions;

a second image sensor responsive to image light for generating a second output signal that is used to produce the output image signal, wherein the second image sensor has a higher resolution than the first image sensor;

a zoom lens for varying the size of the image incident upon the second image sensor; and

a zoom interpolator responsive to a zoom setting of the zoom lens;

wherein the first output signal from the first image sensor is applied to the zoom interpolater, which processes the first output signal to correspond spatially to the image represented by the send output signal.

2. An electronic camera as claimed in claim 1 wherein the control function is image viewing and the camera further includes an electronic display, and the first output signal from the first image sensor is applied to the electronic display to generate a display image for image viewing.

3. An electronic camera as claimed in claim 1 wherein the camera includes an exposure control section for controlling exposure of the second image sensor, and the first output signal from the first image sensor is applied to the exposure control section for controlling exposure.

4. An electronic camera as claimed in claim 1 wherein the camera includes an automatic white balance section that operates on the second output signal from the second sensor, and the first output signal from the first image sensor is applied to the automatic white balance section for obtaining automatic white balance.

5. An electronic camera as claimed in claim 1 wherein the image light is separately directed to the first and second image sensors through respectively separate first and second optical paths including separate optical sections.

6. An electronic camera as claimed in claim 1 wherein the camera includes a main optical assembly for directing image light through a main optical path, and a beamsplitter positioned to receive the image light from the main optical path and split the image light into first and second light paths directed to the respective image sensors.

7. An electronic camera for capturing and processing data relating to an image, said camera comprising:

a first image sensor responsive to image light for generating a first output signal that is used for generating a low resolution thumbnail image;

a second image sensor responsive to image light for generating a second output signal that is used for generating a high resolution still image, wherein the second image sensor has a higher resolution than the first image sensor;

means for synchronizing the image sensors so that the low resolution thumbnail image corresponds to the high resolution still image;

a zoom lens for varying the size of the image incident upon the second image sensor; and

a zoom interpolator rest of the zoom lens;

wherein the first output signal from the first image sensor is applied to the zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal.

8. An electronic camera for capturing data relating to an image through dual optical paths having separate optical systems, said camera comprising:

a first image sensor situated in a first optical path for generating a first output signal that is used for camera control functions;

a second image sensor situated in a second optical path for generating a second output signal that is used for imaging functions, wherein the second image sensor has a higher resolution than the first image sensor; and

a zoom lens in the second optical path and a digital zoom interpolator responsive to a zoom setting of the zoom lens;

wherein the first output signal from the first image sensor is applied to the zoom interpolator so that a zoom ratio of a display image obtained from the first output signal matches the zoom setting of the zoom lens.

9. An electronic camera as claimed in claim 8 wherein the camera further includes an electronic display, and the first output signal from the first image sensor is applied to the electronic display to generate a display image.

10. An electronic camera as claimed in claim 8 wherein the camera includes an exposure control section, and the first output signal from the first image sensor is applied to the exposure control section for exposure control.

11. An electronic camera as claimed in claim 8 wherein the camera includes an automatic white balance section, and the first output signal from the first image sensor is applied to the automatic white balance section for performing automatic white balance.

12. An electronic camera for capturing and processing data relating to an image, said camera comprising:

a first image sensor responsive to image light for generating a first output signal that is used for generating a low resolution image;

a second image sensor responsive to image light for generating a second output signal that is used for generating a high resolution still image, wherein the second image sensor has a higher resolution than the first image sensor;

means responsive to the first output signal for generating a sequence of low resolution images comprising a motion segment immediately before, during, and after the captured high resolution still image;

a zoom lens for varying the size of the image incident upon the second image sensor; and

a zoom interpolator responsive to a zoom setting of the zoom lens;

wherein the first output signal from the first image sensor is applied to the zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal.

13. An electronic camera as claimed in claim 12 wherein the motion segment includes several frames leading and several frames trailing the high resolution still image, along with a frame corresponding to the high resolution still image.

14. An electronic camera for capturing and processing data relating to a sequence of images, said camera comprising;

a first low resolution image sensor responsive to image light for generating a first output signal that is used for generating a motion image display relating to the sequence of images;

a second high resolution image sensor responsive to image light for generating a second output signal that is used to produce an output image signal relating to a selected still image from the sequence of images;

an image storage device;

means for driving the high resolution image sensor to capture the selected still image;

means for storing the selected still image captured by the high resolution image sensor and at least some of the images from the sequence of images captured by the low resolution sensor;

a zoom lens for varying the size of the image incident upon the second image sensor; and

a zoom interpolator responsive to a zoom setting of the zoom lens;

wherein the first output signal from the first image sensor is applied to the zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal.

15. An electronic camera as claimed in claim 14 in which the sequence of images captured and stored from the low resolution image sensor include the images immediately leading and trailing the selected still image.

16. A method of capturing and processing data relating to an image in order to produce an output image signal, said method comprising the steps of:

exposing a low resolution image sensor to image light to generate a first output signal;

exposing a high resolution image sensor to image light to generate a second output signal that is used to produce the output image signal;

generating a display image from the first output signal;

inputting a zoom setting indicative of the amount of image zoom required for the output image signal; and

digitally processing the first output signal with a zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal, to vary the size of the display image reproduced therefrom in order to match the zoom setting.

17. A method for capturing and processing data relating to an image in order to produce an output image signal, said method comprising the steps of:

exposing a low resolution image sensor to image light to generate a first output signal;

providing an optical path with zooming optics;

exposing a high resolution image sensor to image light in the optical path to generate a second output signal that is used to produce the output imaging signal;

generating a display image from the first output signal;

inputting a zoom setting indicative of the amount of image zoom required for the output image signal;

digitally processing the first output signal with a zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal, to vary the size of the display image reproduced therefrom in order to match the zoom setting;

generating a capture signal when the image is to be captured; and

driving, in response to the capture signal, the zooming optics to the amount of zoom required by the zoom setting.

18. A method as claimed in claim 17 wherein the step of digitally processing the first output signal to vary the size of the display image reproduced therefrom in order to match the zoom setting is continually performed during a viewfinding process, and wherein the step of driving, in response to the capture signal, the zooming optics to the amount of zoom required by the zoom setting is performed just prior to the moment of image capture.

19. An electronic camera having an electronic display for capturing and processing data relating to an image in order to produce an output image signal, said camera comprising:

a first image sensor responsive to image light for generating a first output signal that is applied to the electronic display to generate a display image for image viewing;

a second image sensor responsive to image light for generating a second output signal that is used to produce the output image signal, wherein the second image sensor has a higher resolution than the first image sensor;

a zoom lens for varying the size of the image incident upon the second image sensor; and

a zoom interpolator responsive to a zoom setting of the zoom lens;

wherein the first output signal from the first applied to the zoom interpolator, which processes the first output signal to correspond spatially to the image represented by the second output signal.