Optical transform system for three-dimensional object recognition

• US 5,724,447 A
• Filed: 05/16/1995
• Issued: 03/03/1998
• Est. Priority Date: 05/17/1994
• Status: Expired due to Fees

• Current Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Fukushima, Ikutoshi
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): Werner, Brian P.
• Application Number:
  US08/442,347
• Time in Patent Office: 1,022 Days
• Field of Search: 382/106, 382/141, 382/210, 382/276, 382/280, 382/291, 382/103, 382/153, 382/206, 382/211, 382/216, 382/285, 382/152, 382/154, 356/373, 356/379, 356/394, 359/29, 359/561, 359/11, 359/36, 359/41, 359/559, 395/94, 901/46, 901/47, 348/91, 348/94, 348/139
• US Class Current: 382/211
• CPC Class Codes: G06V 10/895 the filter being related to phase processing, e.g. phase-only filters
• CPC Class Codes: G06V 20/64 Three-dimensional objects

Abstract

An image processing method and apparatus in which a range image of a three-dimensional object is obtained, and the inclination of a plane contained in the range image and an approximate area of the plane are instantaneously detected, thereby realizing high-speed recognition of a three-dimensional object. The apparatus includes a range image obtaining device (401) for obtaining a range image as three-dimensional information about an object, an image display device (402) for displaying the obtained range image as a phase distribution, a Fourier transform optical system (403) which employs approximately parallel coherent light for reading out the image displayed on the image display device, and a Fourier transform lens for carrying out Fourier transformation on the image read out by the coherent light, a Fourier transform spectrum detecting device (404) for detecting a Fourier spectrum image obtained by the Fourier transform optical system, and a recognition device (405) for identifying a three-dimensional object which is to be recognized by comparing the data detected by the detecting device with previously inputted information concerning a reference object, thereby detecting a normal to a plane contained in the obtained range image and an approximate area of the plane at high speed.

Claims

1. An image processing apparatus comprising:

means for obtaining a range image as three-dimensional information about an object;

means for displaying obtained range image as a phase distribution;

a Fourier transform optical system including approximately parallel coherent light for reading out the image displayed on said image display means, and a Fourier transform lens for carrying out Fourier transformation on the image read out by said coherent light;

means for detecting a Fourier spectrum image obtained by said Fourier transform optical system;

means for storing reference data including data concerning a vector normal to a surface constituting a reference three-dimensional object which has previously been measured and data concerning an area of the reference three-dimensional object which has previously been measured; and

means for recognizing an object at high speed by comparing information concerning the Fourier spectrum image obtained by said detecting means with said reference data.

3. An image processing apparatus according to claim 1 or 2, wherein said detecting means includes a filter capable of intensity modulation.

5. An image processing apparatus according to claim 1 or 4, wherein said recognition means has means for externally outputting a recognition result.

6. An image processing apparatus according to claim 5, wherein said output means has means for displaying an image.

7. An image processing apparatus according to claim 5, wherein said output means has means for outputting a sound.

8. An image processing apparatus according to claim 5, wherein said output means has means for turning on a lamp.

9. An image processing apparatus according to claim 5, wherein said output means has means for recording a recognition result on a recording medium.

10. An image processing apparatus according to claim 1 or 2, wherein said image display means for displaying the obtained range image as a phase distribution has phase converting means in which the phase distribution is variable in a range of 2 mπ

(m is a natural number).

11. An image processing apparatus according to claim 1 or 2, wherein said image display means for displaying the obtained range image as a phase distribution has a spatial light modulator having a phase modulating function.

12. An image processing apparatus according to claim 1 or 2, wherein said image display means for displaying the obtained range image as a phase distribution has a hologram.

13. An image processing apparatus according to claim 1 or 4, wherein said recognition means includes:

reference data means for storing reference data such as a normal to a plane contained in a range image of an object, and an approximate area of said plane; and

data comparing means for making comparison between said reference data and data such as a normal to a plane contained in the range image, which is obtained by said detecting means, and an approximate area of said plane.

14. An image processing apparatus according to claim 1 or 4, wherein said recognition means determines whether or not said reference data and the object to be recognized are identical with each other.

15. An image processing apparatus according to claim 1 or 4, wherein said recognition means determines which direction the object to be recognized faces by comparing said object to be recognized with said reference data.

16. An image processing apparatus according to claim 1, wherein the reference data in said reference data sorting means is an extended Gaussian image of the reference three-dimensional object which has previously been measured.

2. An image processing apparatus comprising:

object information obtaining means having range image obtaining means for obtaining a range image as information concerning an object;

first image display means for displaying the range image obtained by said object information obtaining means as a phase distribution;

second image display means for dividing the object information obtained by said object information obtaining means into regions, extracting a region from said divided regions and displaying the extracted region as intensity information;

coherent light generating means for emitting approximately parallel coherent light for reading out the images displayed on said first and second image display means;

a Fourier transform optical system for carrying out Fourier transformation by condensing said approximately parallel coherent light; and

detecting means for detecting a Fourier spectrum image by receiving said condensed coherent light,

wherein said first image display means and said second image display means are disposed between said coherent light generating means and said Fourier transform optical system such that the images displayed on said first and second image display means are read out by said coherent light passing through said first and second image display means, said images read out by said coherent light are transformed into a Fourier spectrum image by said coherent light passing through said Fourier transform optical system, and said Fourier spectrum image is detected by said detecting means whereby a normal to a plane of an object contained in the obtained object information and an approximate area of said plane can be detected at high speed.

4. An image processing apparatus according to claim 2, further comprising:

means for storing reference data including data concerning a vector of a normal to a surface constituting a three-dimensional object which has previously been measured, and data concerning an area of a three-dimensional object which has previously been measured; and

recognition means for recognizing a three-dimensional object at high speed by comparing information concerning the Fourier spectrum image, which is obtained by said detecting means, with said reference data.

17. An image processing apparatus according to claim 4, wherein the reference data in said reference data storing means is an extended Gaussian image of the reference three-dimensional object which has previously been measured.