TWM611188U - Optical length measuring apparatus - Google Patents

Abstract

A length measuring apparatus using an optical method includes a light source module for illuminating the surface to be measured, an optical imaging module for focusing the illuminated surface pattern to be measured on a specific image plane, a sensing module for detecting the movement of the image focused by the optical imaging module to obtain displacement signals, and a control module for driving the light source module and receive the displacement signal output from the sensing module, obtaining the measuring information of length and direction after calculation, and then revealing this information on the display module of the apparatus or transmitting the information to an external equipment through a wireless transmission module. The length of the object measured by the measuring apparatus is not limited by the shape, nor is it affected by the surface characteristics of the object. It has the characteristics of measuring the line trajectory of the three-dimensional object, including the length of a straight line, a polyline, or an arbitrary curve. It can also provide the direction information of a path or a track.

Description

Optical length measuring device

This creation is about a measuring device; especially about a device that can measure the length of the linear trajectory of a three-dimensional object. The device uses an optical method to take an image of the object to be measured. The displacement signal is obtained by detecting the movement of the image, and the length is calculated. Measure the value and display it; especially it can be used to measure the length of a straight line, a polyline or an arbitrary curve, and it can also provide the direction information of the path or trajectory.

Length measurement is a very basic but important technique. The traditional method is to use a ruler to measure. If it is a rigid ruler, only the energy is used to measure the straight line distance of the plane; if it is a soft ruler, such as a tape, it can be measured. The length of non-planar or non-linear, but because the ruler needs to fit the object to be measured, whether the two are closely matched will affect the accuracy of the measurement result. With the development of technology, the contact measurement method using rulers has gradually been replaced by non-contact optical measurement. For example, a laser distance measuring device that calculates the time of flight of the beam can directly illuminate the beam. The straight-line distance can be calculated at the target, but because the beam travels in a straight line, this type of measuring device usually only measures the length of a straight line and cannot measure any non-linear objects.

The measurement of non-linear objects is often an unavoidable requirement in engineering. Especially for three-dimensional objects with arbitrary shapes, it is not easy to measure the track length of the surface. Although the three-dimensional appearance of the object can be obtained through optical scanning and the length of the linear trajectory of the object under test can be analyzed, its structure Complex, cumbersome processing process, not practical. For example: the use of optical interference fringes (interference fringe) is used to obtain the three-dimensional shape of the object to be measured after phase restoration, or the structured light is projected, and the phase shift (phase shift) or the amount of fringe deformation is calculated. Obtain the three-dimensional shape of the object to be measured, and use the parallax principle to capture multiple images with multiple imaging devices, and calculate the three-dimensional shape of the object to be measured by the principle of triangulation measurement. These methods are mainly used for 3D scanning of three-dimensional objects. If they are only used to measure the length of linear trajectories, they are complicated and impractical. Therefore, the development of dedicated measurement tools is more pragmatic and necessary.

In order to achieve the above-mentioned linear trajectory length measurement purpose, some foreign researchers have developed a contact measurement method, which uses a specific roller mechanism to connect the counter, and calculates the corresponding number of rotations by the roller circling the object under test. The measured value of the length. For example, the U.S. Patent Application No. US2018/0120081A1 published on May 3, 2018 is an example. Please refer to "Figure 1" to illustrate that the conventional length measuring device 10 is designed with a roller 11 structured at one end of a pen-type device. The end of the device is used to touch the object to be tested and the device is moved to drive the rotation of the roller 11. The length of the moved track can be obtained by multiplying the number of rotations of the roller 11 by the circumference of the roller by an internal counter. This technology has the characteristic of measuring the length of the linear trajectory of any three-dimensional surface. The roller 11 can go around any surface without being restricted by the linear measurement. As long as the trajectory scanned by the device, the path length can be calculated. However, the scroll wheel 11 of this creation needs to be in contact with the surface of the object to be measured to operate, so the surface characteristics greatly affect the measurement results, and there are several disadvantages. For example, if the object to be tested is too smooth to cause insufficient friction with the roller 11, then When the roller 11 circulates and moves, the surface roughness of the object to be measured is too large or the undulation changes drastically, which may cause the roller 11 to not be in close contact and fit. The measured values obtained in these situations cannot show the true path length of the object to be measured, which limits the use occasions of the creation. In addition, with the measurement method of the roller 11 orbiting, only the length of the path can be measured, not Provides the direction information of the trajectory. Therefore, in order to solve these problems, it should be feasible to adopt non-contact measurement methods, especially the use of optical architecture.

In view of the above description, the known length measuring device cannot measure the linear trajectory length of a three-dimensional object. Although some foreign creations propose to use the roller 11 structure to calculate the length of the trajectory swept by the roller circle by circling the object to be measured. However, due to factors such as the friction between the roller 11 and the contact surface of the object and the surface characteristics, the measurement accuracy of this creation is limited by the use occasion, and it cannot provide the direction information of the path or trajectory. Therefore, it is necessary to develop an innovative non-contact measurement. Architecture to solve these problems.

This creation is about a measuring device; especially about a device that can measure the length of the linear trajectory of a three-dimensional object. The device uses an optical method to take an image of the object to be measured. The displacement signal is obtained by detecting the movement of the image, and the length is calculated. Measure the value and display it; especially it can be used to measure the length of a straight line, a polyline or an arbitrary curve, and it can also provide the direction information of the path or trajectory.

Please refer to "Figure 2", which illustrates the basic structure of the optical length measurement device 20 designed by the non-contact optical method in this creation, including a light source module 21 for projecting an illuminating beam 22 to illuminate the surface 23 to be measured; The optical imaging module 24 contains one or more optical lenses 24a for focusing the illuminated surface pattern to be measured on a specific imaging surface due to diffuse reflected light 25; a sensing module 26 , Including the image sensor element 26a and the image processing element 26b, used to detect the pattern image condensed by the optical imaging module 24 and calculate the direction and position change of the image movement, and convert it into a digital signal output; a control module Group 27 can drive the operation of the light source module 21 and the sensing module 26, and obtain the digital signal output by the sensing module 26, and obtain the length and direction after calculation The measured value is then disclosed on the display module 28 of the device, or the information is transmitted to the display interface 29 of the external device through the wireless transmission module 27a (such as Bluetooth or Wifi).

由於影像感測元件26a為二維之畫素(pixel)所組成，每個畫素長寬尺寸為已知的定值，故影像感測元件26a所偵測到之實像23b長度h’可經由成像系統之放大倍率推算出待測表面23上圖案23a之長度h值。再參照「圖3b」，該圖說明光學長度量測裝置20從起始位置相對於待測表面23向左移動L距離後的成像關係，由於圖案23a相對於光學長度量測裝置20為向右移動L距離，故實像23b在光學長度量測裝置20內之影像感測元件26a上相對地向左移動L’，L與L’之比例仍與上述之放大倍率M值相同，因此經由影像處理元件26b之分析計算，可以推導出光學長度量測裝置20之實際移動距離L。 Please refer to "Figure 3", which reveals the basic principle of this creation length measurement. "Figure 3a" illustrates that when the optical length measuring device 20 is initially placed at the starting position to be measured, the surface 23 to be measured is illuminated by the light source module 21, and the pattern reflected light 25 emitted by the pattern 23a of length h on the surface passes through the optical lens 24a converges on the image sensing element 26a into a real image 23b with a length of h' . According to the imaging principle, the imaging system has a fixed magnification M ,

Since the image sensing element 26a of a two-dimensional pixels (pixel) is composed of a known length and width dimensions of each pixel of the predetermined value, so that the image sensing elements 26a detected by the image 23b of the real length h 'via The magnification of the imaging system calculates the length h of the pattern 23a on the surface 23 to be measured. Referring again to "Figure 3b", this figure illustrates the imaging relationship of the optical length measuring device 20 from the initial position relative to the surface to be measured 23 moved to the left by a distance of L , because the pattern 23a is to the right relative to the optical length measuring device 20 Move L distance, so the real image 23b moves L' to the left on the image sensor element 26a in the optical length measuring device 20. The ratio of L to L' is still the same as the above-mentioned magnification M value, so the image processing The analysis and calculation of the element 26b can deduce the actual moving distance L of the optical length measuring device 20.

Please refer to "FIG. 4" again, which illustrates the relationship between the pixel array 26c on the image sensor element 26a, and the initial focusing spot 23c of the real image 23b converged thereon and the moving focusing spot 23d. Each pixel pixel array 26c respectively length and width dimensions P _x and p _y, two focal spot 23c and 23d in the x-axis a distance _x n-th pixels (distance Δ x '), y-axis a distance n _y Pixels (distance Δ y' ), the moving distance L' and actual distance L on the image sensing element 26a can be calculated as: L' =[(Δ x' ) ² +(Δ y' ) ² ] ^½ =[( n _x p _x ) ² +( n _y p _y ) ² ] ^½ (2)

除了可以計算移動距離外，移動之方向角θ’亦可從x,y軸的移動距離計算判斷得到。

In addition to calculating the moving distance, the moving direction angle θ'can also be calculated and judged from the moving distance of the x and y axes.

Since the optical length measuring device 20 continuously moves during operation to measure the length of the object to be measured, the image processing element 26b needs to analyze the moving distance and direction before the real image 23b leaves the sensing range of the image sensor element 26a. , And re-select the initial real image 23b corresponding to the new pattern 23a, and repeat the above analysis steps until the length measurement task ends. The length and direction values obtained by each analysis are received by the control module 27 through the output terminal. The sampling frequency of the analysis can be fixed or changed according to the moving speed of the device. The control module 27 can be used for communication and communication. The control module 27 can accumulate the received movement distance values to obtain the actual total length of the complete path. It can also record the magnitude of the displacement and direction angle of each sample, as a description of the complete path, and provide the path and direction analysis of the linear trajectory.

Since the above-mentioned angle calculation can only obtain the movement direction of the plane, if the object to be measured is a three-dimensional object, the direction calculation of the plane cannot truly describe the three-dimensional trajectory and path. You can add a direction sensing element (such as micro-electromechanical technology) The manufactured gyroscope sensor or goniometer) can detect the spatial orientation, and then the direction information of the three-dimensional trajectory and path can be obtained completely.

This creative effect can improve the shortcomings of the conventional technology. The length of the energy-measured object is not limited by the shape, nor is it affected by the surface characteristics of the object. It has a linear track that can measure a three-dimensional object The characteristics of the trace include the length of a straight line, a polyline or an arbitrary curve. In addition, this creation can also provide the path and direction information of the linear trajectory for the purpose of trajectory drawing.

10: Conventional length measuring device

11: Roller

20: Optical length measuring device

21: Light source module

22: Illumination beam

23: Surface to be measured

23a: pattern

23b: Real image

23c: initial focus spot

23d: Focus the light spot after moving

24: Optical imaging module

24a: Optical lens

25: Pattern reflected light

26: Sensing module

26a: Image sensor

26b: Image processing components

26c: pixel array

26d: Direction sensing element

27: Control module

27a: Wireless transmission module

28: Device display module

29: External device display interface

30: Fiber coupling module

31: Optical fiber light guide module

32: Memory storage module

33: Support and Indication Organization

[Figure 1] is a schematic diagram of the length measuring device disclosed in the US Patent Application No. US2018/0120081A1.

[Figure 2] is the basic structure diagram of the optical length measuring device.

[Figure 3] is an introduction to the basic principles of length measurement in this creation.

[Figure 4] is the description of the image displacement on the image sensor element of this creation.

[Figure 5] is the architecture diagram of the first embodiment of this creation.

[Figure 6] is the architecture diagram of the second embodiment of this creation.

[Figure 7] is the architecture diagram of the third embodiment of this creation.

[Figure 8] is the architecture diagram of the fourth embodiment of this creation.

[Figure 9] is a diagram of the additional support and indication mechanism of the first embodiment of this creation.

Please refer to "Figure 5", which illustrates the first embodiment of this creation. The optical length measuring device 20 includes a light source module 21, which can be a light emitting diode (LED) or a laser diode. (laser diode, LD) element (wavelength can be any value, not limited), with optical lens to effectively collect the divergent light of the light-emitting element into the illuminating beam 22, projected to the surface 23 to be tested, and make the surface 23 to be tested The reflected light in each direction and part of the pattern reflected light 25 are collected by the optical image capturing module 24. The optical imaging module 24 contains one or more optical lenses 24a for focusing the illuminated pattern reflection light 25 on the image sensor element 26a of the sensor module 26, and the image sensor element 26a After the photoelectric signal is converted, the image processing element 26b performs image processing, detects the pattern image condensed by the optical image capturing module 24, calculates the direction and position change of the image movement, and converts it into a digital signal for output. The control module 27 can drive the operation of the light source module 21 and the sensing module 26, and obtain the digital signal output by the sensing module 26, obtain the measured value of the length and direction after calculation, and then disclose the value in This device is on the display module 28. The device display module 28 can display the calculated length value, or the x- axis and y- axis displacement and direction angle value of each movement.

Please refer to "Figure 6", which illustrates the second embodiment of this creation. The optical length measuring device 20 includes a light source module 21, which can be a light emitting diode or a laser diode element (the wavelength can be any value) , Not limited), with optical lenses to effectively collect the divergent light of the light-emitting element into the illuminating beam 22, which is projected to the surface 23 to be tested, and the surface to be tested 23 produces reflected light in various directions. Part of the pattern reflected light 25 passes through the optical Collected by the image capturing module 24. The optical imaging module 24 contains one or more optical lenses 24a for focusing the illuminated pattern reflection light 25 on the image sensor element 26a of the sensor module 26, and the image sensor element 26a After the photoelectric signal is converted, the image processing element 26b performs image processing, detects the pattern image condensed by the optical image capturing module 24, calculates the direction and position change of the image movement, and converts it into a digital signal for output. The control module 27 can drive the operation of the light source module 21 and the sensing module 26, and obtain the digital signal output by the sensing module 26, and obtain the measured value of length and direction after calculation, and then use this value The wireless transmission module 27a transmits the information to the display interface 29 of the external device. The external device display interface 29 can display the calculated length value, or the x- axis and y- axis displacement and direction angle value of each movement.

Please refer to "Figure 7", which illustrates the third embodiment of this creation. The optical length measuring device 20 includes a light source module 21, which can be a light emitting diode or a laser diode element (the wavelength can be any value , Not limited), with optical lenses to effectively collect the divergent light of the light-emitting element into the illumination beam 22, which is guided into the optical fiber light guide module 31 through the fiber coupling module 30, and finally projected onto the surface to be measured 23. The surface to be measured 23 generates reflected light in various directions, and part of the patterned reflected light 25 is guided by the optical fiber light guide module 31 to the optical fiber coupling module 30 and then collected by the optical imaging module 24. The optical imaging module 24 contains one or more optical lenses 24a for focusing the illuminated pattern reflection light 25 on the image sensor element 26a of the sensor module 26, and the image sensor element 26a After the photoelectric signal is converted, the image processing element 26b performs image processing, detects the pattern image condensed by the optical image capturing module 24, calculates the direction and position change of the image movement, and converts it into a digital signal for output. The control module 27 can drive the operation of the light source module 21 and the sensing module 26, and obtain the digital signal output by the sensing module 26, obtain the measured value of the length and direction after calculation, and then disclose the value in This device is on the display module 28. The device display module 28 can display the calculated length value, or the x- axis and y- axis displacement and direction angle value of each movement. This embodiment is different from the aforementioned first and second embodiments. As long as the optical fiber light guide module 31 scans the surface 23 to be measured, the measurement result can be obtained without moving the body of the optical length measuring device 20.

Please refer to "Figure 8", which illustrates the fourth embodiment of this creation. The main purpose of this embodiment is to obtain complete three-dimensional movement direction information. An additional direction sensing element 26d is added to the sensing module 26 of the first embodiment. The direction sensing element 26d can detect the spatial orientation and pass The drive of the control module 27 stores the calculated length and direction data in the memory storage module 32 and displays it on the device display module 28.

Please refer to "Figure 9". Since the imaging object distance of the optical imaging module 24 needs to be kept constant during the path scan measurement process to keep the magnification constant and stabilize the accuracy of the measurement value, it can be The supporting and indicating mechanism 33 is designed at the light exit of the front-end illuminating beam 22 of the optical length measuring device 20 of the foregoing embodiments, in addition to stabilizing the object-image relationship of the optical imaging module 24 In addition, it can also be used as a track positioning or marking for path scanning, and its appearance can be in various forms, which will not be described in detail here.

Although this creation has been disclosed as above in a preferred embodiment, it is not intended to limit this creation. Anyone who is familiar with this art can make various changes and modifications without departing from the spirit and scope of this creation. Therefore, this creation The scope of protection shall be subject to the scope of the attached patent application.

20: Optical length measuring device

21: Light source module

22: Illumination beam

23: Surface to be measured

24: Optical imaging module

24a: Optical lens

25: Pattern reflected light

26: Sensing module

26a: Image sensor

26b: Image processing components

27: Control module

28: Device display module

Claims (10)

A length measuring device using an optical method, which can measure the length of a straight line, a broken line or an arbitrary curve, and provide track direction information, including: a light source module for emitting an illuminating beam to the surface to be measured; an optical imaging module , To focus the illuminated surface pattern to be measured on a specific imaging surface; a sensing module to detect the movement of the image focused by the optical imaging module to obtain a displacement signal; a control module to Drive the light source module and receive the displacement signal output by the sensing module, obtain the length and direction information after calculation and display it; a device display module is used to display the length and direction information calculated by the control module. In the length measuring device described in claim 1, the light source module contains a light-emitting element and an optical lens, which can effectively collect light diverging from the light-emitting element into an illuminating beam. The length measuring device according to claim 1, in which the optical imaging module contains one or more optical lenses, which can produce a real image of the pattern on the surface to be measured, and the object image relationship can be a magnification or reduction ratio. The length measuring device according to claim 1, wherein the sensing module contains an image sensing element and an image processing element. The image sensing element can perform photoelectric conversion on the focused image, and the image processing element can analyze and process the image change . The length measuring device described in claim 1 has a supporting and indicating mechanism at the light exit of the illumination beam at the front end of the device. A length measuring device using an optical method, which can measure the length of a straight line, a broken line or an arbitrary curve, and provide track direction information, including: a light source module for emitting an illuminating beam to the surface to be measured; an optical imaging module , To focus the illuminated surface pattern to be measured on a specific imaging surface; a sensing module to detect the movement of the image focused by the optical imaging module to obtain a displacement signal; a control module to Drive the light source module and receive the displacement signal output by the sensing module, obtain the length and direction information after calculation, and send it to the external device interface through wireless transmission for display. A length measuring device using an optical method, which can measure the length of a straight line, a broken line or an arbitrary curve, and provide track direction information, including: a light source module for emitting an illumination beam; a fiber coupling and light guide module for To guide the illumination beam emitted by the light source module to the surface to be measured, and to guide the reflected light from the surface to be measured back; an optical imaging module to guide the fiber coupling and the light guide module to guide back the pattern reflection of the surface to be measured The light is focused on a specific imaging surface; a sensing module is used to detect the movement of the image focused by the optical imaging module to obtain a displacement signal; A control module is used to drive the light source module and receive the displacement signal output by the sensing module, and the length and direction information are obtained after calculation and displayed; a device display module is used to calculate the length of the control module Display with direction information. The length measuring device according to claim 7, the fiber coupling and light guide module contains the fiber coupling module and the fiber light guide module, the fiber coupling module is used to couple the light beam into the optical fiber, and the fiber light guide module The group is used to conduct light beams. A length measuring device using an optical method, which can measure the length of a straight line, a broken line or an arbitrary curve, and provide track direction information, including: a light source module for emitting an illuminating beam to the surface to be measured; an optical imaging module , Used to focus the illuminated surface pattern to be measured on a specific imaging surface; a sensing module used to detect the movement of the image focused by the optical imaging module to obtain the displacement signal and detect the three-dimensional direction to obtain the space Azimuth signal; a control module to drive the light source module and receive the displacement and direction signals output by the sensing module, and obtain the length and direction information after calculation for display and storage; a device display module to display The length and direction information calculated by the control module is displayed; a memory storage module is used to store the length and direction information calculated by the control module Information for memory and storage. For the length measuring device described in claim 9, the sensor module contains an image sensor element, an image processing element, and a direction sensor element. The image sensor element can perform photoelectric conversion on the focused image, and the image processing element can perform photoelectric conversion on the focused image. The image changes are analyzed and processed, and the direction sensing element can detect the spatial orientation.

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