Three-color imaging on each pixel for increased resolution

• US 6,417,950 B1
• Filed: 08/28/2000
• Issued: 07/09/2002
• Est. Priority Date: 08/28/2000
• Status: Expired due to Term

• Current Assignee: The Board of Regents of the University of Colorado (University of Colorado System)
• Original Assignee: University Technology Corporation
• Inventors: Cathey, Wade Thomas Jr.
• Primary Examiner(s): Mack, Ricky
• Assistant Examiner(s): Hindi, Omar
• Application Number:
  US09/649,118
• Time in Patent Office: 680 Days
• Field of Search: 359/305, 359/247, 359/246, 359/618, 359/495, 359/237, 349/95, 349/42, 257/247, 257/246, 257/618, 257/59, 257/495, 257/237, 345/87
• US Class Current: 359/237
• CPC Class Codes: H04N 25/447 by preserving the colour pattern with or without loss of information

Abstract

Apparatus for increasing color resolution and quality in digital imaging systems temporally modulates red, green and blue light, detects all three colors at each pixel, and band pass filters the detected light to extract values for red, green and blue at each pixel. A detector which preserves the modulation, such as a complementary metal oxide semiconductor detector is used. Alternatively, if an integrating detector array such as a charge coupled device (CCD) is used, the three illumination sources are switched on and off sequentially, and the detector array switches to different integrating circuits for each color. Measurement of the range provides full color, three-dimensional, image data.

Claims

1. Apparatus for improved color imaging comprising:

means for sinusoidally modulating at least two different colors of light;

means for reflecting the modulated light off of an object to be imaged;

means for detecting the modulated reflected light at a plurality of pixels and generating a signal related to the detected light at each pixel, the detecting means including means for preserving the modulation;

means for filtering the signal at each pixel, in order to separate out the values of the signal related to each light color at each pixel according to its modulation; and

means for forming an image, the image forming means combining the values of the signal related to each light color at each pixel.

2. The apparatus of claim 1, wherein the means for detecting comprises a CMOS detector array.

3. The apparatus of claim 1, wherein three colors of light are modulated.

4. The apparatus of claim 1, further including means for computing range to at least one portion of the object by comparing modulation phase of at least one color of light at the modulating means with modulation phase of the at least one color of light at a pixel of the detector array corresponding the the object portion after reflection off the object.

5. The apparatus of claim 1, further including means for computing range to the object comprising:

means for sinusiodally modulating a nonvisible portion of the light spectrum to generate a range signal;

means for transmitting the range signal along the same path as the modulated light; and

means for comparing modulation phase of the range signal at the modulating means with modulation phase of the range signal at pixels of the detector array after reflection off the object.

6. Apparatus for improved color imaging comprising:

means for switching periodically between at least two different colors of light transmitted;

means for reflecting the light off of an object to be imaged;

means for detecting the reflected light at a plurality of pixels and generating a signal related to the detected light at each pixel;

means for sequentially integrating the signal at each pixel, according to the period of each switched color, and generating a signal related to each light color at each pixel; and

means for forming an image, the image forming means combining the values of the signal related to each light color at each pixel.

7. The apparatus of claim 6, wherein the means for detecting comprises a CCD array.

8. The apparatus of claim 6, wherein three colors of light are modulated.