Methods and apparatus for zooming during capture and reproduction of 3-dimensional images

• US 6,414,709 B1
• Filed: 06/07/1995
• Issued: 07/02/2002
• Est. Priority Date: 11/03/1994
• Status: Expired due to Term

• Current Assignee: Hanger Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Synthonics Incorporated (Synthonics Technologies, Inc.)
• Inventors: Palm, Charles S., McLaine, Raymond
• Primary Examiner(s): BOCCIO, VINCENT F
• Application Number:
  US08/483,552
• Time in Patent Office: 2,582 Days
• Field of Search: H04/N 1.302, H04/N 1.500, 348/47, 348/213, 348/48, 348/43, 348/42, 348/46
• US Class Current: 348/47
• CPC Class Codes: H04N 13/10 Processing, recording or transmission of stereoscopic or multi-view image signals
• CPC Class Codes: H04N 13/111 Transformation of image signals corresponding to virtual viewpoints, e.g. spatial image interpolation
• CPC Class Codes: H04N 13/128 Adjusting depth or disparity
• CPC Class Codes: H04N 13/133 Equalising the characteristics of different image components, e.g. their average brightness or colour balance
• CPC Class Codes: H04N 13/15 for colour aspects of image signals
• CPC Class Codes: H04N 13/158 Switching image signals
• CPC Class Codes: H04N 13/167 Synchronising or controlling image signals
• CPC Class Codes: H04N 13/189 Recording image signals; Reproducing recorded image signals
• CPC Class Codes: H04N 13/194 Transmission of image signals
• 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 13/246 Calibration of cameras
• CPC Class Codes: H04N 13/25 using two or more image sensors with different characteristics other than in their location or field of view, e.g. having different resolutions or colour pickup characteristics; using image signals from one sensor to control the characteristics of another sensor
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 13/275 from 3D object models, e.g. computer-generated stereoscopic image signals
• CPC Class Codes: H04N 13/286 having separate monoscopic and stereoscopic modes
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 13/302 for viewing without the aid of special glasses, i.e. using autostereoscopic displays
• CPC Class Codes: H04N 13/324 Colour aspects
• CPC Class Codes: H04N 13/334 using spectral multiplexing
• CPC Class Codes: H04N 13/361 Reproducing mixed stereoscopic images; Reproducing mixed monoscopic and stereoscopic images, e.g. a stereoscopic image overlay window on a monoscopic image background
• CPC Class Codes: H04N 19/597 : specially adapted for multi-view video sequence encoding
• CPC Class Codes: H04N 21/426 : Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/816 : involving special video data, e.g 3D video
• CPC Class Codes: H04N 5/4448 : for frame-grabbing

Abstract

In the capture and display of three dimensional images, techniques are provided for controlling the amount of disparity between left and right images used to create a three dimensional representation to permit three dimensional perception which would otherwise be lost as disparity increased beyond psychological and physiological limits. Both mechanical and electronic means for controlling disparity are shown. Techniques are disclosed for creating three dimensional animations which utilize disparity control for adjusting the perceived depth of an object vis-a-vis a neutral plane. When zooming in on an object with a stereo camera pair, the shift in focal length accompanying the zoom is accompanied by a simultaneous shift in disparity so that the stereo effect is not lost when a target object is very close, a moderate distance, or very far from the cameras. Camera separation is changed as a function of target distance to maintain a fixed fraction of the target distance as a default. The default can be overridden by adjusting disparity independently of the default. Personal discomfort which often accompanies viewing of stereo images is reduced by maintaining camera axes parallel so that unnecessary vertical shift is minimized or eliminated.

Claims

1. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left objective lens and a right objective lens with parallel optical axes,

means for maintaining spacing between said left objective lens and said right objective lens a fixed fraction of a distance to a targeted object.

2. Apparatus of claim 1 in which the fixed fraction is a default value which can be overridden by manual adjustment.

3. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left camera and a right camera with substantially parallel optical axes, and each having substantially identical zoom lenses;

means for adjusting the distance between said optical axes while adjusting focal length of the zoom lenses to hold a location of the neutral plane substantially constant.

4. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left camera and a right camera having substantially parallel optical axes and substantially identical zoom lenses;

means for adjusting disparity while adjusting focal length of the zoom lenses to avoid loss of stereo effect.

5. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left camera and a right camera with parallel optical axes,

a range finder,

a control mechanism, connected to said left camera, said right camera and said rangefinder, maintaining spacing between said left camera and said right camera at a fixed fraction of a distance, specified by said rangefinder, to an object.

6. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left camera and a right camera with substantially parallel optical axes, and each having substantially identical zoom lenses;

a control mechanism which adjusts disparity while adjusting focal length of the zoom lenses to hold a location of the neutral plane substantially constant.

7. Apparatus for capturing three dimensional stereo images of a scene comprising:

a left camera and a right camera; and

a control mechanism which adjusts disparity to hold a location of the neutral plane substantially constant when the distance of the camera to the scene changes.

8. A method for capturing three dimensional stereo images of a scene comprising the steps of:

obtaining a left camera and a right camera having substantially parallel optical axes, and

maintaining spacing between said left camera and said right camera at a fixed fraction of a distance to a targeted object.

9. The method of claim 8 in which the fixed fraction is a default value which can be overridden by manual adjustment.

10. The method of claim 8 in which the fixed fraction is {fraction (1/50)}.

11. A method for capturing three dimensional stereo images of a scene comprising the steps of:

obtaining a left camera and a right camera having substantially parallel optical axes and substantially identical zoom lenses; and

adjusting camera separation while adjusting the zoom lenses to hold a location of the neutral plane substantially constant.

12. A method for capturing three dimensional stereo images of a scene comprising the steps of:

obtaining a left camera and a right camera having substantially parallel optical axes and substantially identical zoom lenses; and

adjusting disparity while adjusting focal length of the zoom lenses to avoid loss of stereo effect.

13. A method for capturing three dimensional stereo images of a scene comprising the step of:

using a left camera and a right camera with parallel optical axes and a range finder, maintaining spacing between said left camera and said right camera at a fixed fraction of a distance, specified by said rangefinder, to an object.

14. A method for capturing three dimensional stereo images of a scene comprising the step of:

using a left camera and a right camera with substantially parallel optical axes and each having substantially identical zoom lenses, adjusting disparity while adjusting focal length of the zoom lenses to hold a location of the neutral plane substantially constant.

15. A method for capturing three dimensional stereo images of a scene comprising the step of:

using a left objective lens and a right objective lens, adjusting the effective distance between the optical axes of the objective lenses to hold a location of the neutral plane substantially constant when the distance of the objective lenses to the scene changes.