Apparatus for measuring three-dimensional shape

• US 6,509,973 B2
• Filed: 04/02/2001
• Issued: 01/21/2003
• Est. Priority Date: 03/31/2000
• Status: Expired due to Term

• Current Assignee: Minolta Co., Ltd. (Konica Minolta Inc.)
• Original Assignee: Minolta Co., Ltd. (Konica Minolta Inc.)
• Inventors: Kiyoi, Kazuya, Tsurutani, Katsutoshi
• Primary Examiner(s): Mack, Ricky
• Application Number:
  US09/822,834
• Publication Number:
  US 20020036779A1
• Time in Patent Office: 659 Days
• Field of Search: 356/601, 356/602, 356/606, 356/607, 356/612, 356/614, 356/623, 250/559.22, 250/559.23
• US Class Current: 356/606
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G01B 11/25 by projecting a pattern, e.g. one or more lines, moiré fringes on the object G01B11/255 takes precedence ; image analysis for depth or shape recovery G06T7/50
• CPC Class Codes: G06T 7/521 from laser ranging, e.g. using interferometry; from the projection of structured light

Abstract

The present invention provides a three-dimensional measuring apparatus comprising a light projector for projecting light to an object, a light receiving element, a light receiving optical system for leading light projected on and then reflected by the object to the light receiving element, and a calculator for obtaining measured data for three-dimensional shape measurement based on signals output from the light receiving element. The light receiving optical system includes a first optical filter which transmits only light having substantially the same range of wavelengths as that of the light projected from the light projector, at least one second optical filter which transmits light having a different range of wavelengths as that of the first optical filter and a filter selector which selectively locates one of the first optical filter or the second filter or filters at an optical path of the light receiving optical system.

Claims

1. A three-dimensional shape measuring apparatus comprising:

a light projector for projecting light to an object;

a light receiving element;

a light receiving optical system for leading light projected on and then reflected by the object to the light receiving element;

the light receiving optical system including a first optical filter which transmits only light having substantially the same range of wavelengths as that of the light projected from the light projector, at least one second optical filter which transmits light having a different range of wavelengths as that of the first optical filter and a filter selector which selectively locates one of the first optical filter or the second filter or filters at an optical path of the light receiving optical system; and

a calculator for obtaining measured data for three- dimensional shape measurement based on signals output from the light receiving element.

2. The three-dimensional shape measuring apparatus according to claim 1, wherein

the second optical filter includes three optical filters each transmitting a wavelength of each of colors of red, green and blue for obtaining a two-dimensional image of the object.

3. The three-dimensional shape measuring apparatus according to claim 1, wherein

the second optical filter includes three optical filters each transmitting a wavelength of each of stimuli X, Y and Z for obtaining a two-dimensional image of the object.

4. The three-dimensional shape measuring apparatus according to claim 1, wherein

the second optical filter includes a plurality of optical filters transmitting wavelengths different to each other for obtaining a two-dimensional image indicating a spectral radiation brightness of the object.

5. The three-dimensional shape measuring apparatus according to claim 1, wherein

thickness of the first optical filter and the second optical filter are so set as to correct color aberration caused by a wavelength of light beams transmitting each of the filters.

6. The three-dimensional shape measuring apparatus according to claim 1, wherein

a diaphragm member for regulating an amount of light to be transmitted is provided for at least one of the first optical filter and the second optical filter.

7. The three-dimensional shape measuring apparatus according to claim 1, wherein

the filter selector comprises:

a rotational plate rotatably provided, with an axis being at the center thereof, to which the first optical filter and the second optical filter are attached at rotational angular positions different to each other and

a motor for rotationally driving the rotational plate as being so controlled as to position the rotational plate in a state where the first optical filter or the second optical filter is inserted into an optical path of the light receiving optical system.

8. A three-dimensional shape measuring apparatus comprising:

a light projector for projecting light to an object;

a light receiving element;

a light receiving optical system for leading light projected on and then reflected by the object to the light receiving element;

the light receiving optical system including a first optical filter which transmits only light having substantially the same range of wavelengths as that of light in a specific range of wavelengths used for the three-dimensional measurement, at least one second optical filter which transmits light in a range of wavelengths used for obtaining a two-dimensional image and a filter selector which selectively locates one of the first optical filter or the second filter or filters at an optical path of the light receiving optical system; and

a calculator for obtaining measured data for three- dimensional shape measurement based on signals output from the light receiving element.

9. The three-dimensional shape measuring apparatus according to claim 8, wherein

the second optical filter includes three optical filters each transmitting a wavelength of each of colors red, green and blue.

10. The three-dimensional shape measuring apparatus according to claim 8, wherein

the second optical filter includes three optical filters each transmitting a wavelength of each of stimuli X, Y and Z.

11. The three-dimensional shape measuring apparatus according to claim 8, wherein

the second optical filter includes a plurality of optical filters transmitting wavelengths different to each other for obtaining an image indicating a spectral radiation brightness of the object.

12. The three-dimensional shape measuring apparatus according to claim 8, wherein

thickness of the first optical filter and the second optical filter are so set as to correct color aberration caused by a wavelength of light beams transmitting each of the filters.

13. The three-dimensional shape measuring apparatus according to claim 8, wherein

a diaphragm member for regulating an amount of light to be transmitted is provided for at least one of the first optical filter and the second optical filter.

14. The three-dimensional shape measuring apparatus according to claim 8, wherein

the filter selector comprises:

a rotational plate rotatably provided, with an axis being at the center thereof, to which the first optical filter and the second optical filter are attached at rotational angular positions different to each other and

a motor for rotationally driving the rotational plate as being so controlled as to position the rotational plate in a state where the first optical filter or the second optical filter is inserted into an optical path of the light receiving optical system.