CN106092828B - The contact angle measuring method focused based on microscope - Google Patents
The contact angle measuring method focused based on microscope Download PDFInfo
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- CN106092828B CN106092828B CN201610404116.0A CN201610404116A CN106092828B CN 106092828 B CN106092828 B CN 106092828B CN 201610404116 A CN201610404116 A CN 201610404116A CN 106092828 B CN106092828 B CN 106092828B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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Abstract
The invention discloses a kind of measuring methods of contact angle, including：Choose a base plane for carrying drop to be measured；Microscopical focussing plane is adjusted, the height and base plane for respectively obtaining base plane are formed by the height in virtual image face after drop to be measured refraction, and the two subtracts each other to obtain difference in height Δ h；Measure the vertical view diameter d for the view field that prepare liquid drops on the direction vertical with base plane of the edge on base plane；In conjunction with light the law of refraction and difference in height Δ h, overlook diameter d and contact angle θ between geometrical relationship synthesis obtain contact angle θ.The present invention can contact angle that is simple under conditions of overlook observation, precisely measuring out droplet to be measured, the shortcoming of the common method that contact angle is observed and measured by side can be made up.
Description
Technical field
The present invention relates to field of optical measurements, the more particularly to measuring method of contact angle.
Background technology
Contact angle is one of the basic parameter for reflecting wettability between solid material and fluent material, it is therefore desirable to carry out essence
It measures really and easily.There are many kinds of the methods, such as goniometry, dynamometry, length method, penetrant method etc. that measure contact angle
(bibliography 1：Latest developments [J] the physical and chemical inspections (physics fascicle) of Ding Xiaofeng, Guan Rong, Chen Pei intelligence Contact Angle Measurement Techniques,
2008,02:84-89.).It is the drop profile from side wherein preferably to measure the method for liquid-drop contact angle, at image
Reason analysis shape obtains contact angle (bibliography 2：It opens and wears, master's thesis, the Contact-angle measurement based on image analysis technology
Technique study, East China University of Science, 2014).Side profile analytic approach has the advantages that simply accurate etc. a variety of thus extensive
Contact angle measurement (such as OCA20 types contact angle measurement of Data Physics companies of Germany) for business.
But side profile analytic approach also has many limitations simultaneously.For example, for tens microns of droplets below,
The problems such as smooth and light diffraction incomplete due to substrate, the profile of droplet is understood from being difficult from side at this time；It is condensing
In experimental study, when many drops of substrate surface dense distribution, since drop mutually blocks, list is also difficult to observe by from side
The integrity profile of a drop；In liquid-drop contact angle dynamic studies, during drop moves in the plane, both it is unfavorable for from side
Observe the two dimensional motion situation of drop, and it is microscopical burnt flat that drop can be caused to leave side due to the variation of movement position
Face, to cannot clearly profile.In short, there are many application scenarios to be not suitable for the drop profile from side, thus it is urgent
Need some methods that directly overlook observation drop can measure contact angle from top.
At present it has been reported that some method (bibliography for measuring contact angle with the mode of overlook observation drop in document
3：Surface science techniques[M].Springer Science&Business Media,2013:P22-
29.).It includes following several that these, which overlook the method measured mainly,：
1) environmental scanning electron microscope (ESEM) oblique view, the i.e. inclination between side observation and overlook observation
The oblique profile of drop is observed in direction using the high-resolution of ESEM, and the contact of droplet is obtained in conjunction with analysis is calculated
Angle；
2) atomic force microscope (AFM) scans pattern, it is desirable that used fluent material can freeze or cure, and then use
Its three-dimensional appearance of AFM scan, to obtain its contact angle；
3) liquid nano dissemination system (NADIS) utilizes NADIS to generate the drop of designated volume, waits for that drop evaporation is dry
Afterwards, the profile that trace is remained after then measuring evaporation with AFM calculates the contact angle of drop by volume and residual print-wheel exterior feature；
4) pipette+light microscope is suitable for millimeter to tens microns of scale, that is, utilizes pipette to generate predetermined body
Long-pending drop reuses light microscope overlook observation and obtains drop and the downward projection diameter of substrate, passes through volume and vertical view
Diameter projected extrapolates the contact angle (bibliography 4 of drop：Dutra G,Martelli C,Canning J.Simple top
down imaging measurement of contact angle for practical assessment of
hydrophilic surfaces[C].Fifth Asia Pacific Optical Sensors
Conference.International Society for Optics and Photonics,2015:96550S-96550S-
4.)；
5) dyestuff that can be fluoresced is added in laser confocal microscope (LSCM) in a liquid, recycles LSCM scannings
The three-dimensional distribution map for going out fluorescence, to extrapolate the contact angle of drop；
6) interference microscope, i.e., for contact angle very little (<30 °) drop, under microscope monochromation illumination, entire liquid
Drop can obtain droplet height, in conjunction with liquid since newton toroidal effect generates interference fringe by being counted to interference fringe
The face profile of drop calculates the contact angle (bibliography 5 of drop：Sundberg M,A,
S.Contact angle measurements by confocal microscopy for non-destructive
microscale surface characterization[J].Journal of colloid and interface
science,2007,313(2):454-460.)。
In addition to the report in document, also there is a small amount of patent to carry out the light of drop contact angular measurement using the mode of overlook observation
Method.For example, by observing method of the droplet surface to the point light source reflection image of multiple constant spacings, calculate that droplet surface is bent
Rate radius calculates contact angle (bibliography 6 in conjunction with drop and substrate contact profile：U.S. Patent number US 2009/
0180106.Friedrich B,Frerichs J G,Kortz E.Method and device for contact angle
determination from radius of curvature of drop by optical distance
measurement:U.S.Patent 7,952,698[P].2011-5-31.).However this method is only applicable to big drop, it is right
Surface is not observed for droplet to reflection image formed by macroscopical point light source.
To sum up, so far, it is connect although having there is many methods that can measure drop by way of overlook observation
Feeler, but these methods are either related to Large expensive instrument material are either required to have specific characteristics matter or being added coloring agent,
The contact angle either measured is limited in scope or is not suitable for droplet etc..Therefore, there is still a need for the measurement side that research and development are new
Method, to make up or improve the limitation or shortcoming of current various methodologies.
Invention content
The present invention is in view of the deficiencies of the prior art, it is proposed that it is a kind of can it is simple, precisely measure out droplet
The measuring method of contact angle, to make up the deficiencies in the prior art place.
According to the measuring method of contact angle provided by the invention, including：
Choose a base plane for carrying drop to be measured；
Adjust microscopical focussing plane, respectively obtain base plane height and base plane through drop to be measured refraction after
The height in the virtual image face of being formed by, the two subtract each other to obtain base plane and are formed by void after drop to be measured refraction with base plane
Difference in height Δ h between image planes；
Measure prepare liquid drop in view field on the direction vertical with base plane of the edge on base plane vertical view it is straight
Diameter d；
In conjunction with light the law of refraction and difference in height Δ h, overlook diameter d and contact angle θ between geometrical relationship synthesis obtain
Contact angle θ.
In some embodiments, contact angle θ is obtained by following formula：
Wherein, n is the refractive index of known drop to be measured.
In some embodiments, contact angle θ can also be obtained by following formula：
Wherein, α1、α2、β1、β2For intermediate parameters；
N.A. it is microscopical numerical aperture.
In some embodiments, difference in height Δ h is the average value or weighted average of multiple measurement results.
In some embodiments, microscope further includes microcobjective, imaging unit and gearshift, and gearshift is extremely
It is few to be connected with one in microcobjective, imaging unit and base plane, to realize that gearshift can drive microscope that will gather
Focal plane changes to different location.
In some embodiments, microscopical number is one.
In some embodiments, the vertical view diameter d of drop to be measured is less than or equal to 10mm.
In some embodiments, the vertical view diameter d of drop to be measured is less than or equal to 1mm.
In some embodiments, the vertical view diameter d of drop to be measured is less than or equal to 0.1mm.
In some embodiments, the measuring method of contact angle further includes the shadow in view of drop its own gravity to be measured
Sound further corrects the value of contact angle θ.
Compared with prior art, the present invention has many advantages, such as that easy to operate, instrument cost is low, applied widely.The present invention
By adjusting microscopical focussing plane position, successively focus on base plane and base plane after drop to be measured refraction institute at
Virtual image face, obtain base plane and base plane after drop to be measured refraction at virtual image face difference in height, in conjunction with the folding of light
The elevation information that rule extrapolates drop to be measured is penetrated, the present invention can contact angle that is simple, precisely measuring out droplet to be measured.
Meanwhile the present invention also further gives the correction algorithm of contact angle, to substantially increase the measurement accuracy of contact angle.Separately
Outside, the present invention can also be measured by simply increasing some gearshifts to simple microscope to realize, or to traditional
Commercial contact angle measurement is increased overlook observation in the form of accessory and measures function.
Description of the drawings
The invention will be described in more detail below based on embodiments and refering to the accompanying drawings.Wherein：
Fig. 1 is the schematic diagram of contact angle；
Fig. 2 is the schematic diagram that optical measurement is carried out using microscope；
Fig. 3 is that the relationship between the relative height differential and contact angle of the focussing plane gone out according to paraxial smooth approximate calculation is bent
Line；
Fig. 4 be the relative height differential of the focussing plane gone out according to the refraction theoretical calculation of light maximum far axial ray error with
Relationship between contact angle.
In the accompanying drawings, identical component uses identical reference numeral.Attached drawing is not drawn according to actual ratio.
Specific implementation mode
The present invention will be further described with reference to the accompanying drawings.
Details described here is exemplary, and is only used for that the embodiment of the present invention is illustratively discussed, it
Presence be to provide for being considered as the most useful and most intelligible description in terms of the principle of the present invention and concept.It closes
In this point, it is not attempted to exceed the CONSTRUCTED SPECIFICATION of the present invention Jie of basic comprehension required degree of the invention here
It continues, those skilled in the art is clearly understood that how to be practically carrying out the several of the present invention by specification and its attached drawing
Kind form.
The measuring method of contact angle provided by the invention, includes the following steps：
Step 1：As shown in Figure 1, choosing a base plane 11 for carrying drop 20 to be measured；
Step 2：In conjunction with shown in Fig. 2, microscopical focussing plane is adjusted, respectively obtains the height and base of base plane 11
Baseplane 11 is formed by the height in virtual image face after drop 20 to be measured refraction, to obtain base plane 11 and base plane 11
The difference in height Δ h being formed by after drop 20 to be measured refraction between virtual image face, the wherein height and substrate of base plane 11 are flat
The difference for the height that face 11 is formed by virtual image face after drop 20 to be measured refraction is the value of Δ h；
Step 3：Measure the projection on the direction vertical with base plane 11 of edge of the drop 20 to be measured on base plane 11
The vertical view diameter d in region；
Step 4：In conjunction with light the law of refraction and difference in height Δ h, overlook diameter d and contact angle θ between geometrical relationship it is comprehensive
Conjunction obtains contact angle θ.
It is understood that the value of Δ h and the value of vertical view diameter d are value necessary to obtaining contact angle θ, therefore step
Two and the sequence of step 3 can also be exchanged with each other.
According to the present invention, as shown in Figure 1, when a drop 20 to be measured is located on base plane 11, due to surface tension
Effect, drop 20 to be measured can be shrunk to spherical crown shape；When from side, the side profile of drop 20 to be measured is at arc-shaped, circle
Tangent line of the arc at solid, liquid, gas three-phase point of interface is exactly drop 20 to be measured in this substrate with angle formed by base plane 11
Contact angle θ in plane 11.
In step 3, it is vertical with base plane 11 that the vertical view diameter d of drop 20 to be measured refers to the edge on base plane 11
Direction on view field diameter or average eguivalent diameter.The present invention is due to the method using microscope overlook observation, institute
Vertical view diameter d to measure drop 20 to be measured is easily.The overhead view image obtained by microscope, further manual measurement
Or the image procossing of automation can obtain the vertical view diameter d of drop 20 to be measured.For example, being obtained by CCD optical imaging elements
After the micro-image for taking drop to be measured, by image transmitting to computer, if the view field for overlooking diameter d of drop to be measured 20 compared with
Circle, can measure the image pixel number shared by projection circular diameter with direct labor, and contact circle is conversed further according to microscopical scale
The corresponding actual length of diameter.In addition, the prior art also gives fits projection circular diameter with software automation image procossing
Specific algorithm (for example, bibliography 7：Cigarette holder stick roundness measurement research [D] Wuhan engineerings of the He Xi based on image procossing is big
Learn, 2012.), it is no longer specifically described in of the invention.
According to the present invention, in step 4, it can be shrunk to spherical crown shape since prepare liquid drops under the action of surface tension, shone
Mingguang City's line can reflect when entering drop to be measured by air in droplet surface to be measured, in conjunction with the law of refraction and difference in height of light
Δ h, the geometrical relationship synthesis overlooked between diameter d and contact angle θ show that contact angle θ, contact angle θ are obtained by following formula：
Wherein, n is the refractive index of drop to be measured.
Above-mentioned equation allows in the case that drop 20 to be measured can be equivalent to ideal spherical crown, is given in conjunction with paraxial light approximation
Dependence between four variables gone out.Paraxial light approximation refers in only considering to be emitted beam by substrate very close to optical path Center
The sub-fraction light of axis.Above-mentioned equation is an implicit equation, but after variation appropriate can in the hope of explicit solution, but
Explicit solution can not also be sought in practical operation, directly acquire numerical solution using software for calculation such as Matlab.Curve shown in Fig. 3 is
Relative height differentialCorrespondence curve between contact angle θ, wherein three curves respectively represent drop refractive index n to be measured
For 1.23,1.33 (water), 1.43 the case where.Vignette in Fig. 3 is in the part of 0 ° of 90 ° of ＜ θ ＜ by curve in ordinate side
To amplified figure.Mapping relations it can be seen from curve between the two are not one-to-one.In 0 ° of ＜ θ of contact angle
In the range of 90 ° of ＜, for each relative height differential measuredThere are two possible contact angle θ values, this requires
The contact angle numerical value measured could finally be determined by also needing to pre-estimate the approximate range of a contact angle in actual measurement.
In the range of 180 ° of 90 °≤θ of contact angle ＜, the two is one-to-one mapping relations, can be directly opposite by what is measured
Difference in heightObtain corresponding contact angle θ values.The solution have the advantages that it is idiotproof, but due to do not consider spherical imaging
The error of error, solving result may be larger.
It is worth noting that, sufficient by difference in height Δ h, refractive index n, this three information of the vertical view diameter d of drop to be measured 20
To extrapolate contact angle θ.Specific projectional technique be not it is unique, can be according to the model of foundation, required precision, to be measured
The size of drop, possible range of contact angle etc. are varied from.
Preferably, in order to further increase measurement accuracy, the present invention further provides a kind of improved projectional technique, directly
It is calculated according to the law of refraction of light, in this way it is further contemplated that the light (more dissipated) farther out to deviation optical path Center axis
Line, the influence that the spherical surface error so as to correct imaging is brought.Contact angle θ is further obtained by following formula：
Wherein, α1、α2、β1、β2For intermediate parameters；
N.A. it is microscopical numerical aperture.
With β2For independent variable, α1、α2、β1Three intermediate parameters can be according to equation group β2It shows；Relative altitude
DifferenceIt can also be by β2It shows jointly with θ；β is determined according to the numerical aperture N.A. of micro objective2Value range；It is right
A relative height differential can be calculated in each given contact angle θValue range；By contact angle θ 0~
Series of values, while the range that drop downward projection diameter d to be measured may be occurred in measurement are divided into the range of 180 °
Interior (such as 0.01~10mm) is divided into series of values；For the vertical view of each contact angle θ and drop to be measured 20 of division
Diameter d calculates the value ranges of corresponding difference in height Δ h in theory；Take weighting flat according to the teachings of difference in height Δ h
It is worth to the calculated value and contact angle θ, the mapping table for overlooking diameter d of drop to be measured 20 of Δ h, wherein asking weighting
Average mode can simply take the average value of teachings bound, can also be to be taken to add according to the intensity of emergent ray
Weights, or other weighting schemes closer to actual value；Finally by actually measured actual situation difference in height Δ h, vertical view
Diameter d tables look-up to obtain Contact-angle measurement value θ.For example, as shown in figure 4, can be calculated according to equation group：It is in refractive index n
When 1.33 (water), microcobjective numerical aperture N.A. are 0.14, deviate the farthest distal shaft light of optical axis and come relative to paraxial light belt
Image error caused by relative height differentialError have corresponding pass line curve with contact angle θ.It is this improved to push away
Calculation method sacrifices the explicit nature of solution and complex, but it is opposite improve measurement accuracy, especially for numerical aperture
The larger microcobjective of diameter.
According to the present invention, as shown in Fig. 2, microscope further includes microcobjective 12, imaging unit 13 and gearshift (figure
In be not shown), gearshift is at least connected with one in microcobjective 12, imaging unit 13 and base plane 11, with realize
Gearshift can drive microscope to change focussing plane to different location.
As shown in Fig. 2, the height of drop 20 to be measured is h, a diameter of d of vertical view of drop 20 to be measured.O on base plane 11
For point positioned at the center in solid-liquid contact region, the light that O points are sent out forms virtual image point O ' after the surface refraction of drop 20 to be measured.O
Difference in height between point and virtual image point O ' is Δ h.Microscopical focal plane is adjusted at the residing height of O ' points first, then
By microscopical focal position adjustment to 20 edge of drop (or near edge locations) to be measured, and adjust residing for focussing plane
Height until microscopes blur-free imaging, it is Δ to record the changing value of microscope focussing plane in the height direction at this time
h.Dashed microcobjective and imaging unit refer to the location of the microscope after movement in figure.In actual mechanical process
In, it, can be in the directions several all around at 20 edge of drop to be measured if microscopical moving direction and substrate are slightly not parallel
It takes several points to be focused the measurement of level difference more, is finally averaged or weighted average.
It is worth noting that, microscopical number is one, different object planes or void by sequencing are focused on
Image planes, rather than simultaneously different surfaces are focused on using two microscopes.Reason for this is that general drop to be measured relative to
Microscope very little is not enough to place the microscope of two or more quantity in the direction of overlook observation.Since most of be tested is waited for
It is all transparent to survey drop 20, and the reflecting rate at 20 top of drop to be measured is relatively low, can not form apparent imaging surface, thus generally very
Microscope is focused on the top of drop 20 to be measured by difficulty.However, since 20 surface of drop to be measured is convex curved surface, drop 20 to be measured
The light that 11 surface of base plane at place is sent out can form a distortion when passing through 20 curved surface of drop to be measured due to refraction effect
The virtual image.The present invention is inspired from actual observation experience, is dexterously formed through drop 20 to be measured according to base plane 11
Reflect the anti-elevation information for pushing away drop 20 to be measured of elevation information of the virtual image.Dioptric imaging rule based on light, by the void observed
Real difference in height, which combines 20 refractive index of drop to be measured and overlooks diameter d, can further extrapolate contact angle θ.
In the measuring method of the contact angle of the present invention, reduces with the size of drop 20 to be measured, shown
Measurement advantage can gradually increase, especially with respect to traditional measurement method from side.Preferably, applicatory
The vertical view diameter d of drop to be measured is less than or equal to 10mm.More preferably, the vertical view diameter d of drop to be measured is less than or equal to 1mm.Into one
Preferably, the vertical view diameter d of drop to be measured is less than or equal to 0.1mm to step.
In addition, the measuring method of contact angle further includes considering the influence of drop its own gravity to be measured to the contact
The value of angle θ is further corrected.Specific modification method has very much, for example, (bibliography 8 according to the literature：Zheng Quan
Water, Lv Cunjing, Hao Peng fly measurement method and Beijing device [P] of a kind of liquid-drop contact angle on solid surface of：CN101539502,
2009-09-23.), any point coordinates (r, w) on the broadside lines of drop meets following equation：
Wherein r is abscissa variable, and w is ordinate variable, and ρ is fluid density (constant), and g is that acceleration of gravity is (normal
Number), γLVFor liquid surface tension coefficient (constant), Δ P0For the inside and outside pressure difference of drop.By formula as it can be seen that for given
ΔP0Corresponding drop contour line equation can be calculated.For a drop contour line equation, setting ordinate w's takes
(maximum value can be obtained by corresponding drop contour line to value range corresponding to drop height h)；The maximum occurrences of abscissa at this time
Range (difference of maxima and minima) is the vertical view diameter d of drop.Thus, it is possible to precompute a series of (Finite Numbers
Amount) drop contour line equation, each contour line equation takes the value range of the ordinate w of a series of (limited quantities), obtains
One group of contour line library.For each contour line can with the software for calculation Program light such as Matlab through the contour line when folding
Rays diameter (according to the law of refraction of light), to calculate the base plane where drop after refraction institute at virtual image face and Ji Duping
Actual situation difference in height Δ h between face, compares the actual measured value of aforementioned actual situation difference in height, acquires difference Error (Δ h)；Simultaneously
Comparison overlooks diameter d and the aforementioned actual measured value for overlooking diameter by what the contour line calculated, acquires difference Error (d).
Error (the contour lines of the root mean square minimum of Δ h) and Error (d) are searched out in contour line library.In order to improve measurement accuracy,
One group of finer contour line library can also be taken to be iterated solution again near the contour line, to obtain more accurately taking turns
Profile.Liquid-drop contact angle θ (the i.e. slopes of contour line minimum point further can be obtained closest to contour line by what is finally solved
The arc-tangent value of w' pays attention to that when the arc-tangent value acquired is negative 180 degree should be added).
It is now typical small with one in order to illustrate protrusion technological progress effect of the present invention relative to conventional side consistency profiles
Measurement of comparison error for drop.The droplet being located on base plane for one, if it overlooks d=50 μm of diameter, height h
=6.7 μm (corresponding contact angle is 30 degree or so), when using conventional side consistency profiles to measure at this time, since common substrate all can
It omits out-of-flatness or has certain roughness, this can cause solid-liquid line of demarcation smudgy, thus bring diameter measurement error delta d=5 μ
M, thus elevation carrection error delta (h)=3 μm calculate Contact-angle measurement error and are up to 13.1 degree；According to of the present invention
Method, due to can clearly be observed that drop profile, d=0.5 μm of diameter measurement error delta, focusing obtain relatively high when overlooking
Spending poor measurement error Δ, (Δ h)=0.1 μm, Contact-angle measurement error is only 2.4 degree at this time.
The present invention successively focuses on base plane and base plane through to be measured by adjusting microscopical focussing plane position
Institute obtains the difference in height Δ h of base plane and the virtual image face of refraction, is pushed away in conjunction with the law of refraction of light at virtual image face after drop refraction
The elevation information of drop 20 to be measured is calculated, the present invention can contact angle θ that is simple, precisely measuring out droplet to be measured.With it is existing
There is technology to compare, the present invention has many advantages, such as that easy to operate, instrument cost is low, applied widely.Meanwhile the present invention is also further
Ground gives the correction algorithm of contact angle θ, to substantially increase the measurement accuracy of contact angle θ.In addition, the present invention can also lead to
Cross simply increase some gearshifts to simple microscope realize measure, or to traditional commercial contact angle measurement with
Accessory form increases overlook observation and measures function.
It should be noted that foregoing example is only for the purpose of explanation, and it is not construed as limiting the present invention.Although
Invention has been described accoding to exemplary embodiment, it being understood, however, that used herein is descriptive and explanation
The language of property, rather than restrictive language.In presently described and modification scope of the appended claims, do not departing from
In the range of spirit of that invention, the present invention can be changed.Although here according to specific mode, material and implementation
Invention has been described for example, but the present invention is not limited in details disclosed herein；On the contrary, the present invention extends to for example
The structure of all identical functions within the scope of the appended claims, methods and applications.
Claims (8)
1. a kind of contact angle measuring method focused based on microscope, including：
Choose a base plane for carrying drop to be measured；
Adjust the microscopical focussing plane, respectively obtain base plane height and base plane through drop to be measured refraction after
The height in the virtual image face of being formed by is formed by virtual image face with base plane to obtain base plane after drop to be measured refraction
Between difference in height Δ h；
Measure bowing for the view field on the direction vertical with the base plane of edge that prepare liquid drops on the base plane
Apparent diameter d；
In conjunction with light the law of refraction and difference in height Δ h, overlook the geometrical relationship synthesis between diameter d and contact angle θ and obtain and contact
Angle θ,
The contact angle θ is obtained by following formula：
Wherein, n is the refractive index of drop to be measured,
Or the contact angle θ is obtained by following formula：
Wherein, α1、α2、β1、β2For intermediate parameters；
N.A. it is the microscopical numerical aperture.
2. contact angle measuring method according to claim 1, which is characterized in that the difference in height Δ h is repeatedly to survey
Measure the average value or weighted average of result.
3. contact angle measuring method according to claim 1, which is characterized in that the microscope further includes micro- object
Mirror, imaging unit and gearshift, institute's displacement apparatus at least with the microcobjective, the imaging unit and the substrate
One in plane is connected, and to realize, displacement apparatus can drive the microscope to change focussing plane to different positions
It sets.
4. contact angle measuring method according to claim 1, which is characterized in that the microscopical number is one
It is a.
5. contact angle measuring method according to claim 1, which is characterized in that the vertical view diameter of the drop to be measured
D is less than or equal to 10mm.
6. contact angle measuring method according to claim 1, which is characterized in that the vertical view diameter of the drop to be measured
D is less than or equal to 1mm.
7. contact angle measuring method according to claim 1, which is characterized in that the vertical view diameter of the drop to be measured
D is less than or equal to 0.1mm.
8. contact angle measuring method according to any one of claim 1 to 7, which is characterized in that further include considering
The value of the contact angle θ is further corrected in influence to drop its own gravity to be measured.
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| CN106501134A (en) * | 2016-12-27 | 2017-03-15 | 吴志远 | The accurate measurement method of low-angle contact angle |
| CN108318385B (en) * | 2018-01-03 | 2020-03-10 | 陕西科技大学 | Optical measurement method for surface tension coefficient and contact angle of liquid |
| CN108956384B (en) * | 2018-05-30 | 2020-04-21 | 陕西科技大学 | Optical method for synchronously measuring surface tension coefficient and contact angle of liquid |
| CN109764829B (en) * | 2019-01-28 | 2021-01-26 | 京东方科技集团股份有限公司 | Contact angle detection module, manufacturing method and detection method |
| CN114216402B (en) * | 2021-12-14 | 2023-09-22 | 西南科技大学 | Method and device for measuring micro deformation of soft substrate caused by surface tension |
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| SU1260752A1 (en) * | 1985-04-22 | 1986-09-30 | Переславский филиал Всесоюзного государственного научно-исследовательского и проектного института химико-фотографической промышленности | Method of determining wetting contact angle |
| JP2002188986A (en) * | 2000-12-22 | 2002-07-05 | Bridgestone Corp | Method and instrument for measuring contact angle |
| CN1266741C (en) * | 2001-07-03 | 2006-07-26 | 东京毅力科创株式会社 | Coating device and coating method |
| US6700656B1 (en) * | 2002-09-17 | 2004-03-02 | The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration | Flow visualization and characterization of evaporating liquid drops |
| CN1265201C (en) * | 2003-03-21 | 2006-07-19 | 中国科学院过程工程研究所 | Device for on line measuring high temperatare fused body surface temsion, contact angle and density |
| JP2004325087A (en) * | 2003-04-21 | 2004-11-18 | Seiko Epson Corp | Method and apparatus for evaluating liquid coating |
| RO122166B1 (en) * | 2006-02-22 | 2009-01-30 | Institutul De Chimie Macromoleculară "Petru Poni" | Appareatus for measuring the contact angle |
| US7486403B2 (en) * | 2006-07-20 | 2009-02-03 | Canon Kabushiki Kaisha | Droplet shape measuring method and apparatus |
| JP2008096252A (en) * | 2006-10-11 | 2008-04-24 | Nec Electronics Corp | Near-field inspection method and device |
| CN101539502B (en) * | 2009-04-30 | 2011-01-05 | 清华大学 | Method for measuring liquid-drop contact angle on solid surface and device thereof |
| RU2460987C1 (en) * | 2011-06-02 | 2012-09-10 | Государственное образовательное учреждение высшего профессионального образования Томский государственный университет (ТГУ) | Method of determining surface tension coefficient and wetting angle |
| CN102507393B (en) * | 2011-11-08 | 2013-05-22 | 国网技术学院 | Coating surface contacting angle measuring device and testing method |
| KR101314530B1 (en) * | 2012-02-28 | 2013-10-04 | 광주과학기술원 | Apparatus and method for measuring contact angle |
| CN103928381B (en) * | 2013-01-15 | 2017-09-05 | 上海华虹宏力半导体制造有限公司 | A kind of aid for measuring wafer contacts angle |
| DE102013111780B4 (en) * | 2013-10-25 | 2016-02-04 | Technische Universität München | Method and device for determining a property of an object |
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