Single sensor chip digital stereo camera

• US 7,061,532 B2
• Filed: 03/27/2001
• Issued: 06/13/2006
• Est. Priority Date: 03/27/2001
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Silverstein, Amnon
• Primary Examiner(s): Vu, Ngoc-Yen
• Assistant Examiner(s): NGUYEN, LUONG TRUNG
• Application Number:
  US09/818,922
• Publication Number:
  US 20020140835A1
• Time in Patent Office: 1,904 Days
• Field of Search: 348/42, 348/45, 348/49, 348/58, 348/65, 348/335, 359/371, 359/376, 359/462
• US Class Current: 348/335
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: H04N 13/211 using temporal multiplexing
• CPC Class Codes: H04N 13/221 using the relative movement between cameras and objects
• CPC Class Codes: H04N 13/229 using lenticular lenses, e.g. arrangements of cylindrical lenses
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control thereof

Abstract

A digital stereo camera using a single sensor array to take both left and right images for stereo (three-dimensional) image capture. In one embodiment, a micro-lens array is used to focus, at a first instant in time, light (“left light”) from a left lens system onto a sensor array for left image capture. Then, the micro-lens array is moved to focus light (“right light”) from a right lens system onto the sensor array for right image capture. In another embodiment, a portion of the left light (the portion having a first polarized direction) and a portion of the right light (the portion having a second polarized direction) are directed to a sensor array; the second polarized direction being orthogonal to the first polarized direction. To capture the left image, a polarization filter is used to allow the left light (having the first polarized direction) to pass toward the sensor array while preventing the right light (having the second polarized direction) from reaching the sensor array. To capture the right image, polarization direction of the polarization filter is switched to allow only the right light (having the second polarized direction) to reach the sensor array.

Claims

1. A camera comprising:

a left lens system;

a right lens system;

a light sensor array;

a polarizing beam splitter (PBS) for combining light from the left lens system and light from the right lens system;

a polarization filter for selecting between light from the left lens system and light from the right lens system, wherein the polarization filter is a liquid crystal device; and

a control unit for controlling the liquid crystal polarization filter to select between light from the left lens system and light from the right lens system.

2. The camera recited in claim 1 further comprising a sensor array to capture the selected light.

3. A camera comprising:

a left lens system;

a right lens system;

a polarizing beam splitter (PBS) for combining light from the left lens system and light from the right lens system;

a light sensor array having a polarization filter allowing one half of sensors of the light sensor array to capture light from the left lens system and the other half of sensors of the light sensor array to capture light from the right lens system, wherein said polarization filter is a liquid crystal window; and

a control unit for switching said liquid crystal window between a first state wherein said polarization filter passes light having a first polarization direction and a second state, wherein said polarization filter passes light having a second polarization direction different from said first polarization direction.

4. A method of capturing a left image and a right image of a scene, the method comprising:

focusing light from a left lens system on a sensor array;

capturing, using the sensor array, the left image at a first instant in time;

focusing light from a right lens system on the sensor array;

capturing, using the sensor array, the right image at a second instant in time using the sensor array; and

using an electrically controllable liquid crystal filter to selectively capture said left image and said right image.

8. The method recited in claim 4, wherein the left light is focused on the sensor array by a polarization beam combiner and a polarization filter.

5. A method of capturing a left image and a right image of a scene, the method comprising:

directing left polarized light from a left lens system on a sensor array, the light polarized in a first direction;

directing right polarized light from a right lens system on the sensor array, the light polarized in a second direction, orthogonal to the first direction

selecting the left polarized light, by switching a liquid crystal filter to a first state wherein it passes said left polarized light, to capture the left image using the sensor array; and

selecting the right polarized light, by switching a liquid crystal filter to a second state wherein it passes said right polarized light, to capture the right image using the sensor array.

6. The method recited in claim 5 further comprising combining the left polarized light and the right polarized light.

7. The method recited in claim 6 wherein a polarized beam splitter (PBS) combines the left polarized light and the right polarized light.