KR101741356B1 - Method for measuring contact angle using smartphone - Google Patents

Method for measuring contact angle using smartphone Download PDF

Info

Publication number
KR101741356B1
KR101741356B1 KR1020160016220A KR20160016220A KR101741356B1 KR 101741356 B1 KR101741356 B1 KR 101741356B1 KR 1020160016220 A KR1020160016220 A KR 1020160016220A KR 20160016220 A KR20160016220 A KR 20160016220A KR 101741356 B1 KR101741356 B1 KR 101741356B1
Authority
KR
South Korea
Prior art keywords
contact angle
droplet
contact
smartphone
automatically
Prior art date
Application number
KR1020160016220A
Other languages
Korean (ko)
Inventor
박태현
이정현
김경훈
양경석
김희진
Original Assignee
경남대학교 산학협력단
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 경남대학교 산학협력단 filed Critical 경남대학교 산학협력단
Priority to KR1020160016220A priority Critical patent/KR101741356B1/en
Application granted granted Critical
Publication of KR101741356B1 publication Critical patent/KR101741356B1/en

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/18—Water
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F9/00—Arrangements for program control, e.g. control units
    • G06F9/06—Arrangements for program control, e.g. control units using stored programs, i.e. using an internal store of processing equipment to receive or retain programs
    • G06F9/44—Arrangements for executing specific programs

Landscapes

  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Software Systems (AREA)
  • Immunology (AREA)
  • General Health & Medical Sciences (AREA)
  • Pathology (AREA)
  • Biochemistry (AREA)
  • Analytical Chemistry (AREA)
  • Theoretical Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

The present invention is characterized in that a droplet (or a droplet) is dropped on an upper surface of an object to be measured, the object to be measured is placed inside the contact angle measuring instrument, and an external light source, which is detachably coupled to the contact angle measuring instrument, A first step of supplying The method of claim 1, further comprising the steps of: after the first step, mounting a smartphone on a cradle provided in the contact angle measuring device, wherein the camera of the smartphone is positioned above a photographing hole formed through the contact angle measuring device, A second step of executing an installed contact angle measurement application; After the second step is performed, a photographing mode is automatically activated on the smartphone through the contact angle measuring application, and a predetermined number of times of measurement objects (for example, And a third step of automatically photographing the contact surface of the droplet at a predetermined time interval; After the third step is performed, any one shot image is selected from the contact surface shot images automatically taken at predetermined time intervals, and a region of interest is enlarged on the selected shot image, A fourth step of displaying; A fifth step of performing a fourth step and displaying a plurality of points by a preset number using a touch pen on a droplet surface on a photographed image displayed on a screen of the smartphone; A sixth step of calculating a contact point coordinate value for each of a plurality of displayed points and a contact point coordinate value for two contact points between the measurement object and the droplet respectively after performing the fifth step; The contact angle measurement application calculates a contact angle through a calculation program previously stored in the contact angle measurement application, and calculates the contact angle so that the error of the contact angle is minimized And a seventh step of calculating a plurality of contact angles corresponding to the contact point coordinate values by the number of the surface coordinate values and then displaying each of the contact angles on the screen of the smartphone. It does not require a separate desktop or a laptop, so it is easy to carry out measurement and carry, and the smartphone is utilized, so that it is less expensive than a conventional expensive contact angle measuring device, and can be easily handled by a user.

Description

[0001] METHOD FOR MEASURING CONTACT ANGLE USING SMARTPHONE [0002]

The present invention relates to a smartphone in which a smartphone installed in a contact angle measuring application is mounted on a contact angle measuring device and a contact angle measuring application is used to photograph a measurement object and a droplet with the camera provided on the smartphone, And a method of measuring a contact angle using the contact angle.

Generally, the adhesion of a measurement object in the fields of display such as LCD, OLED and PDP, printing of electronic materials such as PCB, RFID, microlens, and various micro / nano sensors, bio-chips, , Contact angle measurement as an important measure of surface treatment and polymer surface analysis is required.

Here, as shown in FIGS. 1 (A) and 1 (B), when a droplet (or water droplet) 20 is discharged onto the surface of a horizontal solid (or a measurement object 10), the contact angle maintains a constant lens shape , Which is the angle between the free surface of the droplet and the plane of the solid, which has a relationship expressed by Young's equation between the surface tension of the solid and the liquid, and the interfacial tension.

Here, as shown in FIG. 1 (a), the low contact angle shows high wettability and hydrophilic property, and as shown in FIG. 1 (b), the high contact angle shows low surface energy and hydrophobic ). That is, if the contact angle is small, the ink or liquid droplet spreads well on the substrate, and if the contact angle is large, the ink or droplet is not spread well. Particularly, the application field of the contact angle will be described more specifically. It is used to measure surface pollution degree to prevent contamination of organic materials in hard disk and the like, prediction of performance change before and after coating in coating field, and surface treatment part to improve performance in surface treatment area , Surface tension measurement for use in determining the change in interfacial tension, and surface energy measurement. Thus, various measuring instruments have been developed.

However, since the contact angle measuring apparatus according to the related art uses a separate camera from a desk top or a laptop, a task of taking a droplet discharged to a measurement object with a camera and confirming the shot image is transmitted to a computer It is not easy to carry, and since it is expensive, it is difficult to supply and difficult to handle. In addition, when the captured image is unclear, there is an inconvenience that the user has to re-operate the camera and again take the image.

In order to solve the above problems, an object of the present invention is to provide a contact angle measuring apparatus and a contact angle measuring apparatus, By measuring the contact angle from the shot image after taking a picture, it is easy to carry out the measurement work and portable since a separate desktop or laptop is unnecessary unlike the conventional art, and the price is lower than the conventional expensive contact angle measuring instrument And a method of measuring a contact angle using a smart phone that can be easily handled by a user.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings.

According to another aspect of the present invention, there is provided a method for measuring a contact angle using a smartphone, the method comprising: dropping droplets (or droplets) on an upper surface of a measurement object; A first step of supplying an external light source detachably coupled to the measurement device to the measurement object and the droplet; The method of claim 1, further comprising the steps of: after the first step, mounting a smartphone on a cradle provided in the contact angle measuring device, wherein the camera of the smartphone is positioned above a photographing hole formed through the contact angle measuring device, A second step of executing an installed contact angle measurement application; After the second step is performed, a photographing mode is automatically activated on the smartphone through the contact angle measuring application, and a predetermined number of times of measurement objects (for example, And a third step of automatically photographing the contact surface of the droplet at a predetermined time interval; After the third step is performed, any one shot image is selected from the contact surface shot images automatically taken at predetermined time intervals, and a region of interest is enlarged on the selected shot image, A fourth step of displaying; A fifth step of performing a fourth step and displaying a plurality of points by a preset number using a touch pen on a droplet surface on a photographed image displayed on a screen of the smartphone; A sixth step of calculating a contact point coordinate value for each of a plurality of displayed points and a contact point coordinate value for two contact points between the measurement object and the droplet respectively after performing the fifth step; The contact angle measurement application calculates a contact angle through a calculation program previously stored in the contact angle measurement application, and calculates the contact angle so that the error of the contact angle is minimized And a seventh step of calculating a plurality of contact angles corresponding to the contact point coordinate values by the number of the surface coordinate values, and displaying the contact angles on the screen of the smartphone, respectively.

The fourth step may include a manual selection step of the user selecting any one of the taken images automatically taken at a predetermined time interval, And comparing the contrast values of the boundary points between the droplets with each other through the contact angle measurement application to automatically select one of the shot images having the largest contrast value according to the setting of the contact angle measurement application And any one of the steps is selected.

In the fourth step, the brightness and the saturation of the surface curve portion are automatically set through the contact angle measurement application so that the surface curve of the liquid droplet displayed on the selected shot image through the manual selection step or the automatic selection step is displayed more clearly The image processing method according to claim 1, further comprising:

In addition, the image processing step may include a step of displaying a shot image selected through the manual selection step or the automatic selection step on the screen of the smartphone, and when the user touches and drags the surface curve portion of the droplet displayed on the shot image, The brightness and the saturation of the corresponding portion are automatically adjusted.

In the sixth step, when the measurement object is a transparent or translucent material, both end points of the left and right direction bisector of the droplet reflection surface reflected by the surface of the liquid droplet and the measurement object are automatically recognized as the contact point, When the object to be measured is an opaque material, both end points at which the surface curves of the droplets end are automatically recognized and designated as contact points, and then the coordinate values of the contact points are calculated.

In the seventh step, the three coordinate values of the surface coordinate value and the contact point coordinate value are input to the operation program, and then the coordinate value is substituted into the circular general equation contained in the operation program, Calculating the radius and center coordinates of the droplet source extending along the surface and substituting the calculated radius and center coordinates of the droplet source into the trigonometric function embedded in the operation program to calculate the contact angle.

The contact angle measuring method using a smartphone according to the present invention is characterized in that firstly a smartphone installed with a contact angle measuring application is mounted on a contact angle measuring device and the measurement object and the droplet are photographed by the camera provided on the smart phone through the contact angle measuring application The contact angle is measured from the next captured image. Therefore, a separate desktop or laptop is unnecessary unlike the prior art, so that it is easy to carry out measurement and carrying, and the smartphone is utilized. Therefore, There is an effect that the user can handle easily.

Second, the contact angle measurement application of the smartphone automatically captures the measurement object and the liquid droplet at predetermined time intervals by a predetermined number of times, and automatically adjusts brightness, saturation and sharpness so that the captured image becomes clearer, There is an effect that it is less inconvenient for the user to re-operate the camera to take another picture.

Third, the contact point coordinate value automatically calculated between the droplet on the shot image and the measurement object by the contact angle measurement application of the smartphone and the surface coordinate value of the plurality of points displayed on the droplet surface by the user by using the touch pen There is an effect that the measurement accuracy can be improved by calculating a plurality of contact angles corresponding to the contact point coordinate values by the number of the received surface coordinate values.

1 is a front view showing a contact angle between a measurement object and a droplet,
FIG. 2 is a perspective view illustrating an embodiment of a contact angle measuring apparatus of a contact angle measuring method using a smartphone according to the present invention,
FIG. 3 is a perspective view showing a state in which the smartphone is separated from the contact angle measuring device in the embodiment of FIG. 2,
FIG. 4 is a perspective view showing a state in which the detailed configuration of the contact angle measuring instrument of FIG. 3 is exploded;
5 is a side cross-sectional view showing a side cross-section of the contact angle measuring instrument based on the embodiment of FIG. 2,
FIG. 6 is an image of a measurement object and a droplet taken by a camera of a smartphone on the basis of the embodiment of FIG. 2,
FIG. 7 is a photographing image in which a region of interest is set in the photographing image of FIG. 6,
8 is a photographing image in which a plurality of points on the surface of the droplet and the points of contact between the object to be measured and the droplet among the images shown in Fig. 7 are displayed,
FIG. 9 is a photographing image in which a liquid crystal circle extending along the droplet surface among the photographed images of FIG. 8 is displayed,
FIG. 10 is a view showing a screen of a smartphone in which a plurality of contact angles measured through the shot image of FIG. 9 are respectively displayed,
11 is a flowchart showing a total measuring method of a contact angle measuring method using a smartphone according to the present invention,
12 and 13 are flow charts showing the detailed configuration of the fourth step of the embodiment of FIG. 11,
FIG. 14 is a flowchart showing the detailed configuration of the sixth step of the embodiment of FIG. 11,
FIG. 15 is a plumb chart showing the detailed configuration of the seventh step in the embodiment of FIG. 11; FIG.

Hereinafter, a preferred embodiment of a contact angle measuring method using a smartphone according to the present invention will be described in detail with reference to the accompanying drawings.

First, the contact angle measurement method using a smartphone according to the present invention includes the first to seventh steps.

5 and 11, a droplet (or water droplet) 20 is dropped on the upper surface of the measurement object 10 and then the measurement object 10 is placed on the upper side of the contact angle measuring device 100 And the external light source 200 detachably coupled to the contact angle measuring instrument 100 is supplied to the measurement object 10 and the droplet 20.

Here, as shown in FIGS. 2 to 5, the contact angle measuring instrument 100 has a shape in which an upper part and a lower part are entirely opened, and a side wall is formed and a space is provided therein. A cradle 110 and a shield 130 for coupling the smartphone 300 to be described later are fixed and the cradle 110 supports the rear surface of the smartphone 300 And the length of the smart phone 300 can be adjusted in the left and right direction according to the size of the smart phone 300. The shield 130 is detachably coupled through the fixing protrusion 140 and the fixing hole 150 and the imaging hole 120 is formed so that the camera 310 provided in the smartphone 300 faces the inside . The tilting mirror 160 is installed in the interior of the smartphone 300 so that the camera 310 of the smartphone 300 faces downward, The object 10 and the droplet 20 are inclined at an angle so as to be photographable. The magnifying lens 170 is installed between the tilting mirror 160 and the measurement object 10 and the droplet 20 such that the measurement object 10 and the droplet 20 are magnified and photographed. The projection paper 180 is disposed between the external light source 200 and the measurement object 10 and the droplet 20 such that the contact points and the surface of the measurement object 10 and the droplet 20 are clearly photographed by the backlight effect. Respectively. In addition, a light source insertion hole 190 is formed in the front side portion so as to be coupled with the external light source 200 inserted therein. Since the contact angle measuring instrument 100 is mounted on the floor 100 in a state where the mount 100 and the cover 200 are coupled to each other and the measurement object 10 is positioned below the contactor 100, The external light is blocked except for the supplied light, so that a dark room effect is added to obtain a clear shot image of the measurement object 10 and the droplet 20 together with the above-described backlight effect. If the size of the measurement object 10 is larger than the size of the contact angle measurement device 100, the contact angle measurement device 100 may be positioned on the upper surface of the measurement object 10 to perform the next step .

On the other hand, the operation of dropping droplets (or droplets) 20 on the upper surface of the measurement object 10 can be easily performed through a droplet supplying means such as a syringe, though it is not shown in the figure.

In the second step S200, the first step is performed as shown in FIGS. 3, 5 and 11, and then the smartphone 300 is mounted on the cradle 110 provided in the contact angle measuring instrument 100, The camera 310 of the smartphone 300 is positioned above the photographing hole 120 formed in the contact angle measuring instrument 100 and the contact angle measuring application installed in the smartphone 300 is executed .

Here, the contact angle measurement application installed in the smartphone 300 automatically activates the shooting mode to continuously photograph the measurement object 10 and the droplet 20, image-processes the shot image, It is possible to easily calculate the contact angle only with the smartphone 300 without transmitting data to a separate desktop or laptop unlike the contact angle measuring method according to the related art, This will be described in more detail later in the third step (S300) to the seventh step (S700).

In addition, there is an advantage that the user can easily operate and confirm the smartphone 300 by mounting the smartphone 300 on the contact angle measuring device 100 and placing the screen facing upward.

5 and 11, the third step S300 is to automatically perform a photographing mode on the smartphone 300 through the contact angle measurement application after the second step, (Or input signal) provided on the measurement object 10 and the droplet 20 by a predetermined number of times according to a click (or input signal)

In order that the entire contact surface of the measurement object 10 and the droplet 20 can be photographed, it is necessary to measure the contact angle measured by the smartphone 300 while observing the screen of the smartphone 300 through the activated shooting mode The user can operate the device 100 without difficulty since the device 100 can be moved forward, backward and backward.

In the third step S300, the contact surfaces of the measurement object 10 and the droplet 20 by a predetermined number of times in response to a click (or input signal) of a photographing button provided on the smartphone 300 are displayed at predetermined intervals The reason for the automatic photographing is that the droplet photographing operation during the contact angle measuring operation is performed more easily than the conventional photographing operation and the contact angle measuring accuracy is improved. In other words, in general, the operation of shooting a droplet requires repetitive work in order to obtain a clear shot image. To do so, the user has to click the shooting button of the camera individually, which reduces the efficiency of the operation. There is a problem that a shaking phenomenon may occur. Such shaking reduces the sharpness of the photographed image, which causes the accuracy of the contact angle measurement to deteriorate. Accordingly, the third step S300 of the contact angle measuring method using the smartphone according to the present invention is to solve the problem of the conventional droplet photographing operation when the user clicks the photographing button of the smartphone 300 once, The contact surfaces of the measurement object 10 and the droplet 20 are automatically photographed at predetermined time intervals.

In the fourth step S400, as shown in FIGS. 6 and 11, after the third step is performed, any one of the contact image picked-up images automatically picked up at predetermined time intervals is selected, A region of interest (ROI) is set so that the contact surface is enlarged on the screen of the smartphone 300, and then displayed on the screen of the smartphone 300.

The fourth step S400 includes a manual selection step S420 in which the user selects one of the photographed images automatically photographed at predetermined time intervals as shown in FIG. 12, The contrast value of the boundary point between the measurement object 10 and the droplet 20 displayed on the photographed image automatically picked up by the image pickup device 10 is compared and analyzed by the contact angle measurement application, In the automatic selection step S420 of automatically selecting the shot image, any one step is selected according to the setting of the contact angle measurement application.

In other words, in the manual selection step (S410), a plurality of photographed images are displayed on the screen of the smartphone 300 so as to be enlarged, and a user selects one of the plurality of photographed images And the automatic selection step S420 is a step in which the contact angle measurement application automatically selects one of the plurality of shot images automatically picked up with the highest sharpness. 8, the automatic selection of the photographed image through the contrast of the automatic selection step S420 is performed in a state in which the backlight effect is applied by the projection sheet 180 and the external light source 200 The droplet 20 is displayed close to black so that the lightness value of the measurement object 10 is lower than that of the measurement object 10 so that the contrast of the boundary between the measurement object 10 and the droplet 20 The contrast value is compared and analyzed. The higher the sharpness of the boundary point, the greater the difference in contrast value. Therefore, the contact angle measurement application sets the area including the droplet 20 in advance in a specific area of the shot image, for example, on the shot image, and sets the shot image having the highest difference in contrast value within the specific area You can select automatically. To this end, the contact angle measurement application should include an image processing and image analysis program capable of measuring contrast on an image.

In the fourth step S400, the surface curve of the droplet 20 displayed on the photographed image selected through the manual selection step S410 or the automatic selection step S420, as shown in FIG. 13, And an image processing step (S430) of automatically adjusting brightness and saturation of the surface curve portion through a contact angle measurement application so as to be displayed clearly.

For example, in the image processing step S430, the selected image is displayed on the screen of the smartphone through the manual selection step S410 or the automatic selection step S430, When touching and dragging the surface curved portion with a finger, the brightness and the saturation of the corresponding portion are automatically adjusted, and the captured image is displayed so as to be enlarged so that the surface curved portion can be easily dragged. In addition, the brightness and chroma of the whole photographed image can be automatically adjusted without being limited to this. The brightness and the saturation are automatically adjusted to increase the contrast value and the saturation contrast value, Can be further increased.

In the fourth step S400, a region of interest (ROI) is set such that the contact surface is enlarged on the selected photographed image as shown in FIGS. 6 and 7, and then displayed on the screen of the smartphone 300 This makes it possible to enlarge the contact surface and the surface curved portion of the droplet 20 while cutting unnecessary backgrounds on the photographed image so as to facilitate the work in the fifth step S500 to step S700 described later. .

In the fifth step S500, as shown in FIGS. 8 and 11, after performing the fourth step, a predetermined number of droplets on the surface of the droplet on the photographed image displayed on the screen of the smartphone 300 And displaying a plurality of points. The touch pen is an input means for transmitting an input signal by touching a touch screen type screen of a smart phone, and is a component of a smart phone and can be used freely because it is low cost.

The reason why a predetermined number of points are displayed on the droplet surface on the shot image is to minimize the contact angle measurement error in the seventh step S700 to be described later. For example, as shown in FIG. 8 Similarly, when the predetermined number is 3, a plurality of points (P1, P2, P3) can be displayed on the surface of the droplet. At this time, the photographed image is displayed so as to be enlarged by dragging, button operation or the like so that the user can easily display a plurality of points.

In the sixth step S600, as shown in FIGS. 8 and 11, the fifth step is performed, and then the surface coordinate values for the plurality of displayed points P1, P2, and P3 and the two coordinate values between the measurement object and the droplet The contact point coordinate values for the contact points P4 and P5, respectively.

For example, in the sixth step S600, as shown in FIG. 14, when the measurement object 10 is a transparent or translucent material, the droplet 20 is reflected by the surface of the droplet 20 and the droplet- When the measurement object 10 is an opaque material, both end points at which the surface curve of the droplet 20 ends are automatically recognized, and the contact point is automatically recognized as the contact point. And then the coordinate value of the contact point can be calculated.

In other words, the object to be measured is a display field such as an LCD, an OLED and a PDP required for a printing technique, an electronic material printing field such as a PCB, an RFID, and a microlens, a field of various micro / nano sensors, A transparent / translucent material or an opaque material. In the case of a transparent / translucent material, the reflective surface of the droplet 20 is displayed. In the case of an opaque material, the reflective surface is not displayed, Is displayed. The method of designating the contact points P4 and P5 will be described in detail by first recognizing both ends of the left and right direction bisector of the droplet 20 and the droplet reflection surface 21 reflected by the measurement object 10 The difference in brightness between the droplet 20 and the reflection surface 21 and the measurement object 10 is analyzed through the image processing and image analysis program embedded in the contact angle measurement application and the curve 20 of the droplet 20 and the reflection surface 21 And the extracted curve is divided into upper and lower halves and designated as both ends of the left and right bisector. The recognition of both end points of the surface curves of the droplet 20 is performed by extracting the curves of the droplets by analyzing the difference in brightness between the droplet 20 and the measurement object 10, . Here, the image processing and image analysis program may be a program capable of analyzing or adjusting the brightness and saturation of the shot image as described above in step S400, and may extract the contact points through the analyzed data. For example, FIG. 8 shows that both the droplet 20 and the reflection surface 21 are displayed when the measurement object 10 is a transparent / translucent material, and the contact point can be easily designated to both ends of the bisector. The selection of the two methods for designating the contact point is carried out based on the coordinate values of the surface curves of the droplets 20 extracted by the lightness difference between the measurement object 10 and the droplet 20, The touch angle measurement application determines whether the measurement object is transparent or semitransparent or not, and a setting menu for selecting whether one of the methods is selected or the contact angle measurement application is transparent / translucent or opaque is provided so that it can be easily designated according to the material of the measurement object do.

The contact points P4 and P5 are not limited to being automatically displayed by the contact angle measurement application and can be manually set by the user using the touch pen as in the case of the plurality of points P1, The manual setting can be additionally set to the setting menu.

The calculation of the surface coordinate values for the plurality of points P1, P2, and P3 and the contact point coordinates for the contact points P4 and P5 is facilitated by an image processing and image analysis program built in the contact angle measurement application And a method of calculating coordinate values for a specific position of an image is a well-known technique, and a detailed description thereof will be omitted.

The seventh step S700, as shown in FIGS. 10 and 11, performs the sixth step and then receives any one of the coordinate values and the contact point coordinate values from the surface coordinate values and stores them in the contact angle measurement application A plurality of contact angles are calculated corresponding to the contact point coordinates by the number of the surface coordinate values so that the error of the contact angle is minimized and then displayed on the screen of the smartphone 300 .

In the seventh step S700, as shown in FIGS. 9 and 15, the three coordinate values of the surface coordinate value and the contact point coordinate value are input to the operation program, Calculating a radius (R) and a center coordinate (O) of the droplet source (C) extending along the surface of the droplet by substituting the coordinate values into the equation, and calculating a radius and a center coordinate of the calculated droplet source The contact angle can be calculated by substituting it into the trigonometric function embedded in the equation

Accordingly, the contact angle measuring method using a smartphone according to the present invention is characterized in that first, the smartphone 300 installed with the contact angle measuring application is mounted on the contact angle measuring instrument 100, The measurement object 10 and the droplet 20 are photographed by the camera 310 provided in the main body 10 and then the contact angle is measured from the captured image. Thus, a separate desktop or laptop is not needed unlike the conventional technology, Since the smartphone is utilized, the price is lower than that of the conventional expensive contact angle measuring device, and the user can easily deal with it.

Second, the measurement object 10 and the droplet 20 are automatically photographed at predetermined intervals in the contact angle measurement application of the smartphone 300 by a predetermined number of times, and the brightness, saturation, and sharpness are automatically There is an effect that it is less inconvenient for the user to re-operate the camera and again shoot the camera if the shot image is unclear.

Third, the contact point coordinate value automatically calculated between the droplet on the shot image and the measurement object through the contact angle measurement application of the smartphone 300, and the surface of a plurality of points displayed on the droplet surface by a predetermined number using the touch pen There is an effect that measurement accuracy can be improved by calculating a plurality of contact angles corresponding to the contact point coordinate values corresponding to the number of the surface coordinate values by receiving the coordinate values.

The embodiments of the present invention described above and shown in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

10: object to be measured
20: droplet
100: contact angle measuring instrument 110: cradle
120: photographing hall 130:
140: fixing protrusion 150: fixing hole
160: tilting mirror 170: magnifying lens
180: projection sheet 190: light source insertion hole
200: External light source
300: smartphone 310: camera
ROI: Interest area

Claims (6)

(Or water droplets) are dropped on the upper surface of the measurement object, and then a part of the measurement object is opened and a lower part of the measurement object is opened to form a sidewall so that a space is provided therein, And a cover having a photographing hole penetrating therethrough are respectively coupled to the inside of the contact angle measuring instrument, and a contact angle measuring instrument having a tilting mirror, an enlarging lens and a projection sheet is disposed inside the contact angle measuring instrument, A first step of supplying an external light source possibly coupled to the measurement object and the droplet;
The method of claim 1, further comprising the steps of: after the first step, mounting a smartphone on a cradle provided in the contact angle measuring device, wherein the camera of the smartphone is positioned above a photographing hole formed through the contact angle measuring device, A second step of executing an installed contact angle measurement application;
After the second step is performed, a photographing mode is automatically activated on the smartphone through the contact angle measuring application, and a predetermined number of times of measurement objects (for example, And a third step of automatically photographing the contact surface of the droplet at a predetermined time interval;
After the third step is performed, any one shot image is selected from the contact surface shot images automatically taken at predetermined time intervals, and a region of interest is enlarged on the selected shot image, A fourth step of displaying;
A fifth step of performing a fourth step and displaying a plurality of points by a preset number using a touch pen on a droplet surface on a photographed image displayed on a screen of the smartphone;
A sixth step of calculating a contact point coordinate value for each of a plurality of displayed points and a contact point coordinate value for two contact points between the measurement object and the droplet respectively after performing the fifth step;
The contact angle measurement application calculates a contact angle through a calculation program previously stored in the contact angle measurement application, and calculates the contact angle so that the error of the contact angle is minimized And a seventh step of calculating a plurality of contact angles corresponding to the contact point coordinate values by the number of the surface coordinate values and displaying the contact angles on the screen of the smartphone, respectively,
In the fourth step,
A manual selection step in which a user selects one of the photographed images automatically photographed at predetermined time intervals;
Contrast values of boundary points between the measurement object and the droplet, which are automatically photographed at predetermined time intervals, are compared with each other through the contact angle measurement application, and one of the photographed images having the largest contrast value One of the automatic selection steps automatically selected is selected according to the setting of the contact angle measurement application,
In the fourth step,
The image processing step of automatically adjusting the brightness and the saturation of the surface curve portion through the contact angle measurement application so that the surface curve of the droplet displayed on the selected shot image through the manual selection step or the automatic selection step is displayed more clearly Including,
In the seventh step,
The coordinate values and the contact point coordinates of the droplet are input to the arithmetic program and then the coordinate values are substituted into the circular general equation contained in the arithmetic program, And calculating the contact angle by substituting the calculated radius and center coordinates of the droplet source into the trigonometric function embedded in the calculation program.
delete delete The method according to claim 1,
Wherein the image processing step comprises:
When the user touches and drags the surface curved portion of the droplet displayed on the shot image with the finger, the brightness and saturation of the corresponding portion are displayed on the screen of the smartphone, Wherein the contact angle of the contact angle sensor is automatically adjusted. delete delete
KR1020160016220A 2016-02-12 2016-02-12 Method for measuring contact angle using smartphone KR101741356B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020160016220A KR101741356B1 (en) 2016-02-12 2016-02-12 Method for measuring contact angle using smartphone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020160016220A KR101741356B1 (en) 2016-02-12 2016-02-12 Method for measuring contact angle using smartphone

Publications (1)

Publication Number Publication Date
KR101741356B1 true KR101741356B1 (en) 2017-05-29

Family

ID=59053340

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020160016220A KR101741356B1 (en) 2016-02-12 2016-02-12 Method for measuring contact angle using smartphone

Country Status (1)

Country Link
KR (1) KR101741356B1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108152174A (en) * 2018-01-31 2018-06-12 福州大学 Portable solid surface contact angle measuring device and measuring method
KR20190077974A (en) * 2017-12-26 2019-07-04 경북대학교 산학협력단 Device for measuring chlorophyll on plant leaves using smartphone
KR102339560B1 (en) * 2020-09-05 2021-12-16 (주)화인솔루션 System for Measuring Contact Angle of Liquid Drop on Surface of Substrate

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
LAMOUR, Guillaume, et al. Contact angle measurements using a simplified experimental setup. Journal of chemical education, 2010, 87.12: 1403-1407.(2010.12.31.)*
Tomoyuki Mikami, Contact Angle Measurement, AppStore Apple, <URL: https://itunes.apple.com/kr/app/contact-angle-measurement/id836991479?mt=8>(2014.04.08.)*
WILLIAMS, Darren L., et al. Computerised measurement of contact angles. Galvanotechnik, 2010, 101.11: 2502.(2010.12.31.)*
YOUTUBE, Simple Contact Angle Measurement using a Smartphone(https://youtu.be/Y9IJcxBDpzU)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190077974A (en) * 2017-12-26 2019-07-04 경북대학교 산학협력단 Device for measuring chlorophyll on plant leaves using smartphone
KR102025888B1 (en) 2017-12-26 2019-09-27 경북대학교 산학협력단 Device for measuring chlorophyll on plant leaves using smartphone
CN108152174A (en) * 2018-01-31 2018-06-12 福州大学 Portable solid surface contact angle measuring device and measuring method
KR102339560B1 (en) * 2020-09-05 2021-12-16 (주)화인솔루션 System for Measuring Contact Angle of Liquid Drop on Surface of Substrate
CN114235642A (en) * 2020-09-05 2022-03-25 发仁首路先株式会社 Substrate surface droplet contact angle measurement system

Similar Documents

Publication Publication Date Title
US8456451B2 (en) System and method for differentiating between pointers used to contact touch surface
US7161596B2 (en) Display location calculation means
JP2006010489A (en) Information device, information input method, and program
EP2189835A1 (en) Terminal apparatus, display control method, and display control program
JP2021145209A (en) Electronic apparatus
CN106020436A (en) Image analyzing apparatus and image analyzing method
CN111935393A (en) Shooting method, shooting device, electronic equipment and storage medium
EP3404363A1 (en) Laser receiver using a smart device
KR101741356B1 (en) Method for measuring contact angle using smartphone
TW201007583A (en) Shadow and reflection identification in image capturing devices
CN1630304A (en) Gradient displaying method of mobile terminal
KR102089614B1 (en) Method for taking spherical panoramic image and an electronic device thereof
JP2013228267A (en) Display device, display method, and program
CN103188434A (en) Method and device of image collection
CN113052919A (en) Calibration method and device of visual sensor, electronic equipment and storage medium
KR20140142441A (en) Shooting Method for Three-Dimensional Modeling And Electrical Device Thereof
CN103685837A (en) Image processing apparatus and image processing method
US20070097246A1 (en) Image capture device and method of capturing an image
US11281074B2 (en) Image capturing apparatus improved in operability of operation section
JP5360406B2 (en) Image display device
CN101467885B (en) Noninvasive living body measuring device and a noninvasive living body measuring method
JPH07160412A (en) Pointed position detecting method
KR20110025724A (en) Method for measuring height of a subject using camera module
CN113066134A (en) Calibration method and device of visual sensor, electronic equipment and storage medium
JP2014022977A (en) Imaging apparatus

Legal Events

Date Code Title Description
E701 Decision to grant or registration of patent right
GRNT Written decision to grant