KR20150049815A - Improved 3-D measurement using fiber optic devices - Google Patents

Abstract

The present invention relates to an improved 3-D measurement using fiber optic devices, comprising: an irradiating unit comprising an algebraic optical system and a pattern imaging unit so as to irradiate measurement light on a measurement object; a probe comprising an optical lens and a camera (image sensor) so as to obtain the light reflected after the measurement light irradiated from the irradiating unit is irradiated to the measurement object surface; a shape meter controller which controls the probe to be driven in the scanning direction of the measurement object by receiving a driving power from a driving unit wherein the probe is driven in each direction; and an image processing unit to obtain 3-D information on the measurement object, wherein the relevant images are analyzed by algorithms after the reflected light acquired by the camera is processed. The probe driven by the driving unit irradiates the measurement light transmitted from a pattern generation unit, and the probe comprising a plurality of optical lenses wherein the reflected light is focused on the measurement object, and the probe body is driven by receiving a power from the driving unit. An optical lens wherein the reflected light is reflected by the measurement object and an optical lens in which the measurement light is irradiated in the probe connect the camera separated from the probe to the pattern generation unit through an image guiding optical fiber and deliver light. Through the image guiding optical fiber, the pattern generation unit and camera delivers to the probe the light generated from the pattern generation unit under controlled by the main body, or the shape information is obtained by detecting the reflected light through the image processing algorithms wherein the reflected light obtained from the probe received through the image guiding optical fiber is provided to the image processing unit.

Description

Improved 3-D measurement using fiber optic devices

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved three-dimensional measuring probe using an optical fiber, and more particularly, to a probe structure capable of improving the structure of a probe, thereby greatly improving the performance of a three-dimensional measuring device.

Generally, a technique for measuring the three-dimensional shape and height of a measurement object is divided into a contact-type measurement using a three-dimensional measuring device and a non-contact-type measurement using a light source.

The noncontact measurement method is largely divided into optical interferometry and optical triangulation according to the measurement principle. The optical interferometry includes optical phase interferometry, which is often used for measuring semiconductor patterns or surface morphology of fine metal molds using monochromatic light such as a laser, and optical scanning interferometry, which uses white coherence for white light. However, it is difficult to measure a large area quickly, and an expensive and precise stage is required.

The optical triangulation method is a method of projecting a predetermined constant light onto a measurement surface at an arbitrary angle and analyzing the shape information of the surface by extracting the brightness of the light deformed according to the shape of the surface from another angle. The measurement time is significantly shortened compared with the contact type by using a beam or a moire pattern.

In the method using the moire pattern, a straight glass grating in which a linear pattern with a predetermined interval is engraved with chrome on one surface of the glass is projected onto the measurement object using a projection optical system. In addition, a linear glass grating transfer device is used to transfer linear stripes formed on an object to be measured at regular intervals. A plurality of stripe patterns are formed on the surface of a measurement object by projecting a linear glass grating having a plurality of linear stripes at regular intervals on the measurement object. These stripe patterns are bent according to the height of the measurement object. When a measurement object on which stripes are formed is overlapped with a linear glass grid, a wave pattern of a plurality of curves can be seen. This pattern is referred to as a moire pattern. Since the moire pattern is a contour line formed according to the height of the measurement object, the shape of the measurement object is measured by analyzing the moire pattern. This method using moiré patterns is useful for measuring the entire shape of a measurement object, but in the case of simply measuring only the height of a measurement object, a method using a simpler laser slit beam is used.

As described above, the probe of the three-dimensional shape measuring device for measuring the three-dimensional shape of the measurement object by various measurement methods performs measurement while moving the probe when the three-dimensional shape is to be measured over a large area.

At this time, in order to shorten the measurement time, the position is moved at a high speed, but the larger the weight of the probe, the larger the vibration is generated and the accuracy of measurement of the vibration occurrence is lowered.

Generally, an overall system of a three-dimensional measuring apparatus is roughly described, and includes a system main part and a driving part for acquiring a corresponding image through scanning of a measurement object.

FIG. 1 is a schematic block diagram of a probe-integrated three-dimensional measuring apparatus according to the prior art. The main unit 10 includes an image processing unit 11 for processing an image obtained by acquiring a driving unit and a measuring device controller 12 for controlling the measuring system as a whole ).

The probe 40 acquires the reflected light for each position from the irradiated measurement light while scanning the measurement object by driving the driving unit 41 and acquires the reflected light by the camera (image sensor) 21 and acquires the reflected light to the system main unit 10 . More specifically, the probe 40 includes a pattern generating unit 20 for generating light to be irradiated on a measurement object, a camera 21 for acquiring reflected light, and a projection lens 31 as an optical component. An imaging lens 30 is constituted. The driving means 40 configured in this manner is configured to scan the object to be measured while being driven by a driving device such as motorizing, X, and Y stage mechanisms, detect reflected light (image light), and transmit the signal to the main system.

However, such a probe of a universal measuring apparatus has a pattern generating unit for irradiating light, a plurality of optical systems, a camera 21 for obtaining reflected light, and a plurality of optical systems are included in one mechanism, There is a problem that the driving speed is lowered and the vibration is generated because the weight and the volume become large according to the driving. As a result, there is a problem that the measurement accuracy is lowered.

Therefore, as a major problem in the measurement industry, it is necessary to improve the structure and design direction of the probe so as to achieve simple driving by minimizing the size and weight of the probe.

KR 10-11805090 KR 10-12680430 KR 10-09286090 KR 10-2010-0069590

SUMMARY OF THE INVENTION It is an object of the present invention to provide a probe structure capable of improving measurement speed and measurement stability by improving the probe structure of a three-dimensional measuring apparatus.

Particularly, in the shape measuring apparatus of the present invention, in the structure of the conventional shape measuring apparatus, a camera (image sensor) constituted by a main part and a probe and configured to irradiate the measurement light to the measurement object and obtain the reflected light, In the measuring system composed of the probe structure and the main part capable of obtaining shape information by processing the reflected light obtained here, the components are separated so as to minimize the weight and the volume of the probe, so that the weight of the probe driven by the driving part is minimized The present invention aims to provide a measuring device capable of improving mechanical stability by suppressing vibration caused by a driving operation, designing a low-capacity driving part, and improving the durability of a driving mechanism.

It is another object of the present invention to provide a high-precision three-dimensional measuring device capable of improving the measurement precision, which is a key task of the measuring device, by improving the mechanical stability, and consequently obtaining the accurate measurement result by minimizing the measurement error .

According to an aspect of the present invention, there is provided an apparatus for measuring an object to be measured, the apparatus comprising: an irradiator configured to include a plurality of optical systems and a pattern image unit for irradiating measurement light to a measurement object; And a camera (including an image sensor) for receiving the driving power from the driving unit for driving the probe in each direction and controlling the driving power to be driven in the scanning direction of the measurement object A three-dimensional shape measuring apparatus comprising a controller and an image processor for processing reflected light obtained by the camera and analyzing the image with an algorithm to obtain three-dimensional information of the object to be measured, the apparatus comprising: The measurement light transmitted from the pattern generator is irradiated, A probe is constituted by a plurality of optical lenses for forming reflected light on water, and the probe body is driven to receive power from the driving unit. An optical lens for irradiating the measurement light from the probe and a reflection light The optical lens is connected to a camera and a pattern generating unit which are divided from the probe through an image guiding optical fiber. The pattern generating unit and the camera receive the light generated by the pattern generating unit under the control of the main unit, Or transmits the reflected light obtained from the probe to the image processing unit through the image guiding optical fiber and detects the reflected light through the image processing algorithm to obtain the shape information.

The probe includes an image-forming lens for receiving reflected light, and a projection lens for projecting pattern light corresponding to the measurement light onto the object to be measured. The image-forming lens and the projection lens are fixed to the probe body, And the reflected light is acquired by irradiating the measurement light while scanning the measurement object by the light source.

The three-dimensional measuring device may further include an image processing unit that receives and processes the reflected light corresponding to the measurement object acquired by the camera connected to the probe and the image guiding optical fiber, And a control unit for controlling both the image processing unit and the driving unit.

The apparatus further includes a relay lens provided on the pattern generator and the camera, respectively, for connecting the optical fiber connected to the probe to the pattern generator and the camera.

The image guiding optical fiber may be any one of a pixel-division-type image guiding optical fiber and a self-focusing guiding optical fiber.

In addition, the probe may include a relay lens disposed on one side of the probe body, one side of each of which is connected to the image guiding optical fiber so as to transmit an optical signal, and each of the image guiding optical fibers, And the relay lens is positioned so that the projection lens and the image-forming lens face the relay lens, respectively, in the opposite direction in which the relay lens is located, so that the measurement light irradiated from the projection lens is irradiated onto the measurement object, As shown in FIG.

The image guiding optical fiber is connected to the pattern image part and the camera, respectively, and is connected to the body of the probe. The other part of the image guiding optical fiber is allowed to flow along the probe moving according to the driving of the driving part. .

Since the weight and volume of a probe can be reduced by using an optical fiber in a three-dimensional shape measuring instrument as described above, the probe can be rapidly driven and vibration can be suppressed, There is an advantage that a three-dimensional shape measuring device capable of realizing high measurement can be provided.

Particularly, the three-dimensional measuring device according to the present invention comprises a probe only in the optical system so as to minimize the weight and volume of the probe corresponding to the driving region, and the pattern image portion for providing the measuring light and the camera receiving the reflected light, The probe is connected to the optical fiber to reduce the weight and the volume of the probe corresponding to the actual driving area. Therefore, it is possible to suppress the vibration that may occur during the scanning operation, to reduce the load on the driving part, and to improve the mechanical durability. Can be provided.

In addition, since the measuring apparatus according to the present invention and the probe included therein are connected with an optical fiber and are designed very lightly, the driving noise that can be generated in the scanning process can be minimized, thereby achieving a highly stable measuring system.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of a probe-integrated three-dimensional measuring apparatus according to the prior art,
FIG. 2 is a configuration diagram of an improved three-dimensional measuring probe using an optical fiber according to the present invention,
3 is a view showing an imaging guide optical fiber applied in the present invention,
FIG. 4 is an overall configuration diagram of an improved three-dimensional measuring device using an optical fiber according to the present invention,
5 is a perspective view showing a probe including only an optical system in a three-dimensional measuring instrument according to the present invention,

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of an improved three-dimensional measuring probe using an optical fiber according to the present invention will be described in detail with reference to the accompanying drawings.

An improved three-dimensional measuring apparatus using an optical fiber according to the present invention includes an irradiating unit including an optical system and a pattern image unit for irradiating measurement light with measurement light; And a controller (not shown) which is configured to transmit the driving power from the driving unit that drives the probe in each direction and drives it in the scanning direction of the measurement object And an image processing unit for processing reflected light obtained by the camera and analyzing the image by an algorithm to obtain three-dimensional information of the measurement object, the three-dimensional shape measuring apparatus comprising: The probe irradiates the measurement light transmitted from the pattern generator A probe is constituted by a plurality of optical lenses for imaging reflected light, and the probe body is driven to receive power from the driving unit. An optical lens for irradiating measurement light from the probe and reflected light reflected from the object to be measured The pattern generating unit and the camera are controlled by the main unit to transmit the light generated by the pattern generating unit to the pattern generating unit, And transmits the reflected light obtained from the probe to the image processing unit through the image guiding optical fiber and detects the reflected light through the image processing algorithm to obtain the shape information.

The present invention relates to an improved three-dimensional measuring probe using an optical fiber according to the present invention. The probe is scanned in order to measure the shape information of the object in three dimensions. In this case, the structure of the measuring probe driven for scanning is greatly simplified, And minimizes the weight, thereby minimizing the vibration noise generated during driving.

2 is a configuration diagram of an improved three-dimensional measuring probe using an optical fiber according to the present invention.

The three-dimensional shape measuring apparatus according to the present invention comprises a computer 100 for largely controlling an image processing and a three-dimensional measuring instrument, a pattern generating unit 200 for irradiating measurement light, that is, pattern light, A probe for irradiating the object with measurement light or receiving the reflected light and acquiring the reflected light is provided between the main body and the optical fibers 202 and 203. The camera 210 includes a camera 210 for acquiring light reflected from the object, The probe includes a projection lens 310 for projecting measurement light and an imaging lens 300 for acquiring reflected light.

The main body (not shown) controls the shape measuring apparatus as a whole and includes an image processing unit 110 and a three-dimensional shape measuring unit control unit 120. The image processing unit processes the light reflected by the object to be measured and obtains the light obtained by the camera (image sensor) by an algorithm. The image processing unit can obtain and process the light through various algorithms such as a moiré algorithm, a triangulation method and an interference method.

The three-dimensional shape measuring unit control unit controls the measuring unit, controls the driving unit of the probe, and controls the camera, the pattern generating unit, and the image processing unit.

The technical feature of the present invention is that the structure and size of the probe can be greatly simplified by connecting the measurement probe to the main body and the optical fiber 203 as described above.

To this end, the measurement light generated by the pattern generation unit is connected to the probe through the optical fiber 203, and the camera is connected to the probe and the optical fiber 202 to obtain the reflected light obtained from the probe.

At this time, relay lenses 201 and 202 are provided at the pattern generating unit and the camera front end, respectively, which are connected to the optical fiber, and optical fibers are connected to the relay lenses 201 and 202, respectively.

3 is a view showing an imaging guide optical fiber applied in the present invention.

The optical fiber according to the present invention corresponds to an image guiding optical fiber for transmitting an image. The principle of a system for transmitting optical images using optical fibers is pixel-division type and self-focusing type. In the pixel division type, a plurality of optical fibers corresponding to pixels are aligned and bundled as shown in (a). Although the transmission image is divided into finite number of pixels and strictly does not have a linear image transfer characteristic, the chromatic aberration in transmission is small and the number of pixels (filament fiber) is increased, It gets closer.

A self-focusing imaging guiding optical fiber (see (b)) uses a focusing optical fiber to transmit an image using the image quality of the light propagating through the optical fiber. Self-Focusing Imaging Guiding Because the refractive index of the fiber is the largest on the central axis and gradually decreases toward the periphery, the image can be transmitted using the imaging characteristics of the light propagating through the fiber.

The probe 400 also includes a relay lens (not shown) for connecting the optical fiber to the imaging lens and the projection lens.

Accordingly, the probe 400 includes only an imaging lens and a projection lens. The lens is fixed to the probe structure body, and the probe is connected to a separate driving unit 410 to be driven to scan the measurement object 500 As it is separated from the main body, it can be lightly driven. As a result, high-speed scanning and minimization of vibration are realized, so that quick and accurate shooting is possible.

In the meantime, according to the present invention, the structure of the probe driven to scan a measurement object in the three-dimensional shape measuring apparatus is improved to reduce the volume and light weight, thereby improving the driving speed and minimizing the measurement noise due to the vibration drop. .

The system configuration of the image processing unit, the pattern generating unit, the camera, and the three-dimensional shape measuring unit controller constituting the three-dimensional shape measuring apparatus described in the present invention can be variously changed depending on the characteristics of the measuring method and the measuring system, In order to construct various conventional measurement systems such as moire measurement, interference method measurement, confocal measurement method, etc., it is needless to say that a system corresponding thereto can be designed, and a structure for scanning an object by connecting the main body of the systems and the probe with an optical fiber Are all included in the scope of the present invention.

Since the probe of the shape measuring apparatus is connected to the body through the optical fiber to transmit the measurement light and the reflected light, the overall measurement performance such as light weight of the probe, high-speed drive, and noise reduction can be improved. It can show excellent performance in the field.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. On the contrary, those skilled in the art will appreciate that many modifications and variations of the present invention are possible without departing from the spirit and scope of the appended claims. And all such modifications and changes as fall within the scope of the present invention are therefore to be regarded as being within the scope of the present invention.

100: Computer
110:
120:
200: pattern generator
201, 202: relay lens
210: camera
203: Optical fiber
300: image forming lens
310: Projection lens
400: probe
410:
500: object to be measured

Claims (7)

An optical lens for acquiring light reflected from the measurement object after the measurement light emitted from the irradiation unit is irradiated onto the surface of the measurement object, and a camera A shape meter control unit configured to form a probe including a sensor and to drive the probe in a scanning direction of the measurement subject by receiving driving power from a driving unit driving the probe in each direction; A three-dimensional shape measuring apparatus comprising an image processor for analyzing an image with an algorithm to obtain three-dimensional information of the object to be measured,
The probe driven by the driving unit may comprise a plurality of optical lenses configured to irradiate the measurement light transmitted from the pattern generation unit and image the reflected light on the object to be measured so that the probe body receives the power from the driving unit, In addition,
An optical lens for irradiating the measurement light in the probe and an optical lens for receiving the reflected light reflected from the measurement object are connected to the camera and the pattern generation unit, which are divided and configured by the probe and the image guiding optical fiber,
The pattern generating unit and the camera transmit the light generated by the pattern generating unit under the control of the main unit to the probe through the image guiding optical fiber or receive the reflected light obtained from the probe through the image guiding optical fiber, Dimensional measurement device using an optical fiber provided to a processing unit and detecting reflected light through an image processing algorithm to obtain shape information. The probe according to claim 1,
An imaging lens for receiving reflected light; and a projection lens for causing a pattern light corresponding to the measurement light to enter the measurement object,
Wherein the imaging lens and the projection lens are respectively fixed to the probe body and irradiate measurement light while scanning the measurement object by the driving means to obtain reflected light. The apparatus according to claim 1, wherein the three-
An image processing unit that receives and processes the reflected light corresponding to the measurement object acquired by the camera connected to the probe and the image guiding optical fiber,
And a controller for controlling all of the probe, the camera, the pattern generating unit, the image processing unit, and the driving unit of the three-dimensional measuring device, and the main unit. The method according to claim 1,
And a relay lens provided on the pattern generator and the camera, respectively, for connecting the optical fiber connected to the probe to the pattern generator and the camera. 2. The image guiding optical fiber according to claim 1,
An improved three-dimensional measuring probe using an optical fiber consisting of a pixel-division-type image guiding optical fiber or a self-focusing guiding optical fiber. The probe according to any one of claims 1 to 5,
A relay lens is provided on one side of each of the probe bodies in order to transmit an optical signal in connection with the image guiding optical fiber, and each image guiding optical fiber connected to the pattern image portion and the camera is connected to the relay lens,
And the projection lens and the imaging lens are respectively positioned so as to face the relay lens in opposite directions in which the relay lens is placed, and the measurement light emitted from the projection lens is irradiated on the measurement object, reflected and incident on the imaging lens An improved three - dimensional measuring probe using an optical fiber. The image guiding optical fiber according to claim 1 or 5,
And the other one is connected to the body of the probe so as to be able to flow along the probe that flows according to the driving of the driving unit, Measuring probe.

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