Measuring endoscope

• US 4,656,508 A
• Filed: 06/06/1985
• Issued: 04/07/1987
• Est. Priority Date: 06/08/1984
• Status: Expired due to Term

• Current Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Yokota, Akira
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Kostak, Victor R.
• Application Number:
  US06/742,057
• Time in Patent Office: 670 Days
• Field of Search: 358/98, 358/88, 358/100-107, 358/96, 358/901, 128/4-11, 356/4.5, 356/5, 350/510
• US Class Current: 348/45
• CPC Class Codes: G01B 11/2509 Color coding
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/84 for processing colour signals
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/134 based on three different wavelength filter elements

Abstract

A measuring endoscope for making three-dimensional measurements of a object without using a special lattice and without hampering direct observation of the object. The measuring endoscope includes a light supply source for supplying illumination, and an illumination variation device for providing a plurality of particular illuminations, and illumination transmission means including a plurality of fiber optic cables. The fiber optic cables have a first input section separated from a second input section. The second section receives one particular illumination which the first section does not. At the output end of the fiber optic cables, fiber optic cables from the first section are interlaced, row-by-row with the fiber optic cables from the second section. An illumination lens then directs the light from the fiber optic cables onto the object. A lattice-shaped light pattern then appears on the object. Light reflected from the object is received by an objective lens system and is directed to an imaged sensor. The image sensor includes a large number of regularly arranged picture elements. Image processing devices then convert the received image into electrical signals. The image processing means process selected electrical signals from among all electrical signals received. These selected electrical signals are obtained from picture elements from positions where the lattice of the object image is formed on the light receiving surface. These selected electrical signals may then be processed to provide a three-dimensional measurement of the object. A control device controls the supply of light to the fiber optic cables to ensure that the light is emitted from the fiber optic cables in a lattice form. Finally, a display device connected to the image processor provides a display according to the three-dimensional image of the object.

Claims

1. A measuring endoscope for measuring an object, comprising:

an endoscope body having a foremost end portion;

illumination light supply means housed within said body of said endoscope and having a number of regularly arranged fine light-emitting sectors, for supplying illumination, said illumination light supply means comprising a light guide including a bundle of a plurality of optical fibers, said bundle having two light-incidence end portions, said plurality of optical fibers being arranged at a light-emission end of said light guide to form a plurality of alternate rows of fibers in such a manner that those optical fibers included within one of the two light-incidence end portions and those optical fibers included within the other light-incidence end portion are arranged in alternate rows relative to each other at the light-emission end portion of the light guide;

image focusing means, housed in said foremost end portions of said endoscope body, for forming an image of said object from illumination reflected from said object;

image pickup means, housed within said endoscope body and having a number of picture elements disposed regularly at a position at which said image of the object is formed by said image focusing optical means, for picking up said object image;

controlling means, associated with said illumination light supply means, for controlling the illumination supplied to said fine light-emitting sectors to cause said illumination light supply means to emit light in lattice form;

image processing means, connected to said image pickup means, for performing a three-dimensional measurement of said object; and

display means, connected to said image processing means, for displaying information corresponding to the said three-dimensional measurement.

2. A measuring endoscope according to claim 1, further comprising a magnetic disc memory connected to said image processing means to store information regarding said three-dimensional measurement.

3. A measuring endoscope according to claim 1, further comprising an X-Y plotter connected to said image processing means.

4. A measuring endoscope according to claim 1, wherein said illumination light supply includes an incandescent light supply, and an infrared light cutting filter disposed adjacent one of said two light-incidence end portions, and wherein said image pickup means comprises a solid-state image sensor and a color-separating stripe filter disposed adjacent said solid-state image sensor.

5. A measuring endoscope according to claim 1 wherein said image pickup means comprises a solid-state image sensor constructed so that, at a time of observation using an infrared light as said illumination, signals are read out from every other row or column of said picture elements.

6. A measuring endoscope according to claim 1, wherein

said image pick-up means comprises a solid-state image sensor and a color-separating stripe filter disposed adjacent said solid-state image sensor, and wherein said controlling means comprises a rotary filter facing the light-incidence end faces of said light guide and has a red light transmitting sector, a green light transmitting sector, a blue light transmitting sector and an infrared light transmitting sector, and wherein said infrared light transmitting sector is constructed to cause an infrared light to impinge onto only one of the two light-incidence end portions of said light guide.

7. A measuring endoscope according to claim 6, further comprising driving means coupled to said image focussing means for moving said image focussing means to focus illumination emitted from said bundle on said object only during a period in which said infrared light transmitting sector is inserted in a path of light from said light supply means in synchronism with a rotation of said rotary filter.

8. A measuring endoscope according to claim 6 wherein said light supply means comprises an LED array having successibly arranged roads of LEDs emitting a red light, a green light, a blue light, and an infrared light, respectively, and wherein said controlling means comprises a driving circuit for repetitively causing said rows of LEDs of said LED array to emit a red light, a green light, a blue light, and an infrared light, respectively, in a predetermined order.

9. Endoscope apparatus for forming a three-dimensional image of an object, comprising:

illumination supply means for providing a plurality of distinct illuminations including infrared illumination;

illumination transmission means, having an illumination input end and an illumination output end, for receiving and transmitting said plurality of illuminations, said illumination transmission means having a first group of light channels separated from a second group of light channels at said illumination input end, said light channels being arranged in alternating rows of said first and second groups, respectively, at said illumination output end, said first group of light channels transmitting said infrared illumination;

projecting means adapted for projecting illumination from said illumination output end onto said object;

objective means for focusing illumination reflected from said object;

image sensor means for receiving the focused illumination reflected from said object and providing electrical signals corresponding thereto; and

processing means for receiving said electrical signals and providing output signals having information corresponding to said three-dimensional image of said object.

10. Apparatus according to claim 9 wherein said image sensor means includes a plurality of light sensor elements arranged in a matrix-like structure having columns and rows, and wherein said image sensor means provides said electrical signals from every other row or every other column.

11. Apparatus according to claim 9 wherein said image sensor means includes a plurality of light sensor elements arranged in a matrix-like structure having columns and rows, and wherein said processing means includes memory means for storing said electrical signals column-by-column or row-by-row, and wherein said processing means processes the stored electrical signals from every other row or every other column.

12. Apparatus according to claim 9 wherein said illumination supply means includes:

an illumination source means for supplying a single illumination; and

illumination variation means, interposed between said illumination source means and said illumination transmission means for causing said single illumination to be transposed into said plurality of distinct illuminations in a time dependent manner.

13. Apparatus according to claim 12 wherein said illumination variation means includes a rotary filter having an infrared transmitting sector adapted to allow said infrared illumination to enter said first group of light channels while preventing said infrared illumination from entering said second group of light channels.

14. A measuring endoscope for measuring an object, comprising:

a main body for holding said endoscope, said main body having proximal and distal end portions;

light supply means for supplying a plurality of distinct illuminations;

illumination light emitting means, arranged within said distal end portion of said main body and including a plurality of fine light emitting sections, for emitting said plurality of distinct illuminations, only one part of said light emitting sections emitting one of said distinct illuminations to form a lattice-shaped light emitting pattern;

image forming means arranged within said distal end portion of said main body, for forming an image of said lattice-shaped light emitting pattern on said object when said illumination light emitting means forms said lattice-shaped light emitting pattern;

objective means arranged within said distal end portion of said main body, for forming an image of said object from illumination reflected from said object, said image being formed at an image forming position of said objective means;

image pickup means disposed at said image forming position of said objective means and having a light receiving surface comprising a plurality of picture elements arranged in columns and rows, for receiving said image from said objective means and converting it into electrical signals;

image processing means, connected to said image pickup means, for processing selected electrical signals from among said electrical signals provided by said image pickup means, said selected electrical signals being obtained from picture elements corresponding to a position where said image of said lattice-shaped light emitting pattern is formed on said light receiving surface, said image processing means forming a three-dimensional measurement of said object;

control means disposed adjacent said light supply means, for controlling said distinct illuminations provided to said fine light emitting section so that said illumination light emitting means emits a lattice-shaped light pattern; and

display means coupled to said image processing means, for displaying information corresponding to said three-dimensional measurement.

15. A measuring endoscope according to claim 14, wherein said light supply means comprises an LED array having successively arranged rows of LEDs emitting a red light, a green light, a blue light and an infrared light, respectively, and wherein said control means comprises a driving circuit for repetitively causing said rows of LEDs of said LED array to emit a red light, a green light, a blue light and an infrared light, respectively, in a predetermined order.

16. A measuring endoscope according to claim 15, wherein said image pickup means comprises a solid-state image sensor constructed so that, at a time of observation using an infrared light as one of said distinct illuminations, signals are read out from every other row or every other column of the picture elements.

17. A measuring endoscope according to claim 15, wherein said image pickup means comprises a solid-state image sensor having picture elements arranged in lattice form.

18. A measuring endoscope according to claim 14, wherein said illumination light emitting means comprises an optical fiber bundle formed of a plurality of optical fibers and has first and second bifurcated portions at a light incidence end of said fiber bundle, a light emission end face of said bundle being arranged so that respective fibers of said bifurcated portions are alternatedly disposed in rows, said bundle being arranged so that said light emission end face is provided within said distal end portion of said main body, and wherein said light supply means projects light upon respective bifurcated portions of said light incidence end face, and wherein said control means comprises a light cutting means provided between said light incidence end face and said light supply means, for making at least a part of said distinct illuminations incident upon only one of said bifurcated portions.

19. A measuring endoscope according to claim 18, wherein said control means further comprises an infrared cutting filter arranged between said light supply means and one of said bifurcated portions, and wherein said image pickup means comprises a solid-state image sensor and a color-separating stripe filter disposed adjacent said solid-state image sensor, said image pickup means having a lattice-shaped stripe which transmits only infrared light.

20. A measuring endoscope according to claim 18, wherein said control means further comprises a rotary filter facing the light incidence end face of said optical fiber bundle and has a red light transmitting sector, a green light transmitting sector, a blue light transmitting sector, and an infrared light transmitting sector.

21. A measuring endoscope according to claim 20, wherein said image pickup means comprises a solid-state image sensor having picture elements arranged in lattice form.

22. A measuring endoscope according to claim 20, wherein said image pickup means comprises a solid-state image sensor constructed so that, at a time of observation using an infrared light as one of said distinct illuminations, signals are read out from every other row or every other column of the picture elements.

23. A measuring endoscope according to claim 22, further comprising driving means coupled to said image forming means to move said image forming means to focus light emitted from said bundle on said object only during a period in which the infrared light transmitting sector is inserted in a path of light from said light supply means in synchronism with a rotation of said rotary filter.