JP2557005Y2 - Optical measuring instrument - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical measuring instrument capable of clearly observing and measuring the contour shape of a side image of an object to be measured.

[0002]

2. Description of the Related Art Conventionally, when a footprint is measured, for example, it is necessary to observe and measure a side image thereof, that is, a contour shape of a toe portion, an instep portion, and a heel portion. Measuring instruments designed to measure by scanning are now in practical use.

[0003]

However, in the measuring instrument utilizing the laser light as described above, the apparatus becomes large and disadvantageous in cost.

[0004] In addition, when a side image of an object to be measured is simply photographed, if the contrast is not clear to determine the contour shape from the photographed image, the image processing becomes complicated and inaccurate. Have.

[0005] In contrast to this point, E is added to the background of the DUT.
A technique has been proposed in which the contour shape of the object to be measured can be obtained as an image having a high contrast with a background portion by installing a uniform illumination means such as an L illumination plate. It has been found that the illuminating means has a problem that the contour is illuminated and the shape is measured small.

That is, in the uniform illuminating means for the background portion, illumination light from oblique directions is totally reflected on the contour surface of the object to be measured, and the reflected light is photographed and observed. For example, when measuring the outline shape by image processing, the part that is observed brightly and brightly is determined to be the background part, and the shape of the object to be measured will be measured small, and accurate Measurement may not be performed.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide an optical measuring instrument capable of photographing and observing a side image of an object to be measured clearly and accurately.

[0008]

In order to achieve the above object, an optical measuring instrument of the present invention mounts an object to be measured on a mounting table, takes a side image of the object to be measured through a reflection means, The contour shape of the object to be measured is measured, and a uniform illuminating means is installed on a background portion of the object to be measured on the mounting table, and a portion located outside the object to be measured in the side image at a predetermined interval. And a light blocking member for blocking the light of the uniform illumination means.

It is preferable that the light-shielding member is provided in a structure in which the light-shielding position is variable so that the light-shielding portion can be changed according to a change in the size and the position of the measured object.

[0010]

In the optical measuring instrument as described above, the side image of the object to be measured is reflected by the reflection means toward the image pickup device and is picked up.
Uniform illumination means such as an illumination plate is provided, so that the contour shape of the object to be measured can be obtained as an image having a high contrast with the background part, and the light shielding member applies the uniform illumination means to the contour surface of the object to be measured. The illumination light obliquely incident is reduced, and the total reflection light on the contour surface is reduced from entering the observation side. Measurement of the dimensions of the contour shape can be accurately performed by simple image processing.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of an optical measuring device according to one embodiment.

The measuring device 10 includes a mounting table 11 which is placed in a horizontal state and on which an object W such as a foot is mounted. On the side of the mounting table 11, a first reflecting means 12 for reflecting a side image of the workpiece W upward is disposed. As the first reflection means 12, for example, a plane mirror has a tilt angle (tilt angle).
In addition, they are inclined with the horizontal position (reflection distance) in a predetermined state. Further, an image pickup device 15 such as a television camera for photographing the side image reflected in the horizontal direction by the second reflection means 13 is provided above the first reflection means 12. The second reflection means 13 and the imaging device 15
Are actually arranged in a direction perpendicular to the paper surface rotated by 90 °.

On the other hand, a uniform illuminating means 17 is provided on a background portion of the measuring object W of the mounting table 11, that is, on a side opposite to the first reflecting means 12. This uniform illuminating means 17 is an EL
(Electroluminescence) A lighting plate 18 is attached to a substrate 19 and is formed in a vertical shape. The EL illumination plate 18 has, for example, a dielectric layer containing a phosphor laminated between a transparent electrode on the front surface and a metal plate on the rear surface, and connects an AC power supply to the transparent electrode and the metal plate to make the entire EL surface uniform. A well-known EL lamp that emits light at a high brightness and whose brightness can be changed by setting the voltage and frequency of the power supply (for example, by adjusting the voltage with a slider) is employed.

Further, an EL as the uniform illumination means 17
As shown in FIG. 2, the front side of the illuminating plate 18, that is, a part of the illuminating surface, has a plate-like shape that blocks the light of the uniform illuminating means 17 at a portion located before and after the object to be measured W in the side view. Light shielding members 21 and 22 are provided. The first light-blocking member 21 disposed on the toe side in front of the DUT W covers the outer portion from the front of the toe portion to the upper part of the finger at a predetermined distance from the contour line to shield light. The second light-blocking member 22 disposed on the heel side of the device under test W covers the outer portion at a predetermined interval from the contour of the heel and covers the outer portion from the rear to the upper portion. Also, both light shielding members
The lower ends of the 21, 21 are inserted into the grooves 24 of the mounting table 11, and the upper parts thereof are supported by guide rails 25 so as to be slidable in the front-rear direction.

On the other hand, uniform illumination means in the mounting table 11 described above.
As shown in FIG. 1, a condenser lens 27 is provided on the side opposite to the side 17 with the uneven surface with the surface to be measured W side. The condenser lens 27 is composed of a Fresnel lens and has a focal length. The relationship with the arrangement position of the imaging device 15 is set so as to be the installation position of the imaging lens in the imaging device 15, and a telecentric optical system is configured.

For photographing the object W, first, the object W is mounted on the mounting table 11, and the front and rear first and second light shielding members 21 and 22 are slid with respect to the object W. The light shielding member is provided at a predetermined interval with respect to the contour position of the workpiece W.
Adjust so that 21,22 is positioned. Thereby, the light shielding position is changed according to the change in the size and the mounting position of the DUT W.

When the EL illuminating plate 18 is energized, the EL illuminating plate 18 emits light of a predetermined brightness, and the side image passes through the condenser lens 27 and the reflecting means 12 and 13 to form the image pickup device 15.
Will be taken by At this time, the condenser lens 27
Due to the telecentric optical system associated with the interposition, the optical path on the object W side from the condenser lens 27 is parallel to the optical axis, and the contour shape does not change regardless of the position of the object W due to parallax. , An accurately projected side view is taken.

That is, as in the embodiment, the photographing lens of the image pickup device 15 has a small diameter, and the side image photographed through the reflecting systems 12 and 13 spreads radially from one point of the photographing lens to move the object W to be measured. The image becomes a viewed image, and a shape is formed by an optical path extending obliquely outward from the center side, and the outline is shifted inward and outward due to a change in the position of the outline of the workpiece W due to the parallax. The measurement of the size from the above causes the measurement error with the size of the actual contour shape to be eliminated as a measurement in the parallel optical path by the interposition of the condenser lens 27.

The side image of the object W captured by the image pickup device 15 has a dark foot and a bright background portion, and the light-shielding members 21 and 22 allow the total reflection on the contour surface of the object W to be measured. This prevents the contour from shining and allows the contour to be photographed with a clear density difference and a clear contrast. The captured image is processed at a slice level of a predetermined brightness by an image processing device, for example, and the outline is recognized. Based on the processed image, the dimensions and the like of each part such as a toe, a heel, and an instep are measured. The image processing can be performed by simple processing based on the contrast.

According to this embodiment, the installation of the uniform illuminating means 17 and the slidable light shielding members 21 and 22 allow the side images of the objects to be measured W having different sizes to be totally reflected by a simple structure. It is possible to take a picture with a sharp outline without accompanying. In addition, by installing the condenser lens 27, the contour shape of the side surface of the workpiece W can be projected and photographed accurately without generating parallax, and accurate measurement can be performed.

As the uniform illuminating means 17, the above-mentioned EL illuminating plate 18 is optimal from the viewpoint of the light quantity and the plate-like structure, but other illuminating means utilizing a diffusing plate or the like can be appropriately employed. is there.

The light-shielding members 21 and 22 may be formed of the above-mentioned plate-like members, may be of a curtain shape, or may be of a type in which a liquid crystal plate is partially opaque according to the size of the object W to be measured. Can be adopted as appropriate. The shape of the light-shielding portion may be set only at a portion where total reflection is to be particularly prevented, and may be arbitrarily set according to the shape of the object W to be measured. Further, both the front and rear members of the light shielding members 21 and 22 are not slidable.
May be provided such that the front first light shielding member 21 is fixed and only the rear second light shielding member 22 is slid.

On the other hand, in the above embodiment, two reflecting means are provided since the image pickup device 15 is disposed horizontally at the upper part. However, the image is directly taken by the first reflecting means 12. You may.

Alternatively, both feet may be photographed simultaneously. That is, the other mounting table, the reflection means, and the imaging device may be disposed symmetrically to FIG. 1, and the uniform illumination means and the light shielding member using the EL illumination plate may be installed on the opposite surface of the substrate as the background. .

Further, in the above embodiment, only the side image is taken, but the bottom image may be taken at the same time. For example, the mounting table 11 is formed of a transparent member or frosted glass, and a reflecting means for reflecting a bottom surface image of the device under test W to the side below the mounting table 11 and a bottom image reflected by the reflecting means are positioned upward. The second reflecting means
13 is provided with reflection means for reflecting light, and the imaging device 15 is provided.
Therefore, it is preferable that the side image and the bottom image are simultaneously photographed adjacently in the same visual field. In this case, it is necessary to illuminate the bottom surface of the device under test W with a light source from below.
The reflecting means provided below the mounting table 11 may be used as a half mirror to illuminate from below.

The condenser lens 27 includes:
Although the above-mentioned Fresnel lens is preferable from the viewpoint of its practicality and the like, a lens using another condenser lens can be appropriately used.

The object W to be measured in the present invention is not limited to the feet as in the above embodiment, but can be applied to various articles requiring a contour image from the side.

[0028]

According to the present invention as described above, a uniform illuminating means is provided on a background portion of an object to be measured placed on a mounting table,
By providing the side image through the reflection unit, a side image of the DUT that is dark against a bright background portion by the uniform illumination unit can be obtained as an image having a high-contrast and clear contour shape. Further, by providing a light-blocking member that blocks illumination light outside the object to be measured, total reflection light on the contour surface is reduced, and this contour portion is illuminated to prevent the contour shape from being observed small. In addition, it is possible to accurately measure the dimensions of the contour shape even by simple image processing.

[Brief description of the drawings]

FIG. 1 is a front view showing a schematic configuration of an optical measuring instrument according to an embodiment of the present invention.

FIG. 2 is a schematic side view of a measuring unit.

[Explanation of symbols]

 10 Measuring device W DUT 11 Mounting table 12,13 Reflection means 15 Imaging device 17 Uniform illumination means 18 EL illumination plate 21,22 Light shielding member

Claims (1)

(57) [Scope of request for utility model registration] An optical measuring instrument in which an object to be measured is mounted on a mounting table, a side image of the object to be measured is photographed via a reflection means, and a contour shape of the object to be measured is measured. In addition, a uniform illuminating means is installed on a background portion of the object to be measured on the mounting table, and a light shielding member for blocking light of the uniform illuminating means in a portion of the side image located outside the object to be measured at a predetermined interval is arranged. An optical measuring instrument characterized by being installed.