The shape that a drop takes on a surface depends on the surface tension of the fluid and the nature of the surface. Nov, 2017 quick tutorial on using imagej to process contact angle data. New, innovative software advance drop shape for contact. The position of the drop in the image remains unchanged when the viewing angle is adjusted. Does anyone know how to use matlab to measure contact angle of droplets. Simple, accurate method for contact angle measurement. Now, we can use laptops, computers, tablets or smart phones to measure the angle of anything, around us anytime, anywhere. The contact angle goniometer comes complete with userfriendly measurement software. Ic measure contains many measurement tools, including tools for the measurement of lengths, angles, circles and polygons. The commercial softwares available today are still very limited.
Measure length, area, angle and circumference on images with image measurement. In fact people often perform contact angle measurements, by applying the sphere approximation, neglecting in this way the gravity effect, or by calculating the tangent of the profile without limit the drop volume. The possibility of estimating solid surface tensions from contact angles relies on a relation which has been recognized by young in 1805. The other method is done by tilting either the sample stage or the whole instrument with the tilting cradle.
The technique of the sessile drop is today the most widely used method to measure this parameter. Notice there is no way to calibrate contact angle data. An equilibrium of vectorial forces dictates the contact angle. The camera may be placed to either look exactly horizontally at the drop or look down at, say, 3. This emphasizes the point that contact angle measurement uncertainty is almost entirely due to baseline uncertainty.
Ic measure measure onscreen lengths, angles, circles. A raw image from iphone 6s frontfacing camera with pdmslens. C at the three phase contact line of a deposited drop. This method does not require complicated image capture and analysis hardware and software. The integrated pump delivers accurate droplets in steps of 0. For more information on contact angle, click on one of the products below or view the complete range via the following link. If contact angle is greater than 90, the surface is said to be nonwetting with that liquid. The common method of measuring the contact angle in capillary rise in porous media is by using the lucaswashburns equation which is derived from poiseulles law of liquid flow in capillary rise. Contact angle measurement combines high technology test instrumentation and a nondestructive testing method to allow an accurate, objective and repeatable analysis to be made.
All of these need special ways to measure contact angle. Contact angle measurement has wide application in studying the wettability of a surface. New, innovative software advance drop shape for contact angle measurement intuitive user interface, powerful video analysis and a wide range of functions with advance drop shape, we have developed a new, innovative software package for measuring contact angle. Where the curve crosses the baseline, its tangent is used to determine the contact angle. Measuring the threephase contact angle of nanoparticles at. The complete range of contact angle meters goniometers theta theta lite theta qc. Infineon technologies ibm globalfoundries the company oeg was created 1991. The contact angle is the angle at the point where this baseline meets the droplet edge.
All of these methods have their pros and cons which makes some more suitable for certain types of substrates and applications. A patented half angle measurement method eliminates the difficulties associated with tangent angle measurement methods. In our experience, confirmed by the literature as well, the maximum volume, whose profile as a. Portable optical contact angle meter interfacial tensiometer. Mar 30, 2018 an automatic contact point detection algorithm was developed to allow the instrument to correctly detect the drop contact points. There have also been several specialized advances customized for productionline environments 7. Students doing this experiment should go directly to ncb 228. Therefore, dynamic contact angle measurement can indicate chemical and topographical heterogeneity. Jan 31, 2017 clinically, this can be observed by viewing the interaction between the tears and the lens surface. Oca optical contact angle measuring and contour analysis. Contact angle measurement cnet download free software. The optical contact angle measuring and contour analysis systems of the oca series combine high resolution optics, exact liquid dosing and. Free view, show, create and edit ms powerpoint presentations. How to measure a contact angle without using sophisticated.
Contact angle measurement system contact angle measurement systemis a tool to study the wetting behaviour of a liquid on solid. In the following you will learn about the possibilities that the optical analysis of drop contours offers and about our oca models with their extensive range of accessories and intuitive software control. Originally the program was conceived to assess the angle between north and a given point on any map open on the screen, therefore the background of the application window is transparent and the angle is measured from the positive yaxis and clockwise. Contact angle is the angle formed by a liquid at the phase boundary where a liquid, gas and solid intersect. The contact angle is the angle formed between a drop of liquid and the surface of the lens. Contact angle measurements using the drop shape method. Advance drop shape is a common software platform for all our laboratory instruments and mobile solutions for analyzing the wetting of solid surfaces.
A bespoke contact angle measurement software and experimental. The first contact angle goniometer was designed by dr. Optical metrology software development image processing. Contact angle measurement equipment uk dyne testing. In fact people often perform contact angle measurements, by applying the sphere. The wellknown young equation describes the balance at the threephase contact of solidliquid and gas. Rugged and simpletouse the theta and theta lite contact angle meters offer highly repeatable qc and analytical tool for measuring the contact angle on a variety of substrates. The common direct measurement of contact angles of a liquid drop on a flat and smooth solid is not applicable to powders and dry porous foods. Advance drop shape is a common software platform for all kruss laboratory instruments and mobile solutions for analysing the wetting of solid surfaces. This approach is inherently imprecise since the apex is a flat region covering a range of angles. This includes prepared and flexibly modifiable templates for new measurements which ensure exact reproducibility of measuring conditions. In the following you will learn about the possibilities that the optical analysis of drop contours offers and about our oca models with. There are a range of techniques available in the common image manipulation programs like coreldraw 8 and adobe photoshop 9. The necessity to have a selfdeveloped software comes by considering that.
The complexity of contact angle analysis ranges from. Using the contact angle meter you can compare the effects of a range of surface treatments and gather data that correlates to various surface conditions e. Measure length, area, angle and circumference you can measure both the length, area, circumference or angle of an object with image measurement. Or can anyone recommend any free software or codes to measure contact angle. The baseline of the measurement is the horizontal line that represents the solid on which the droplet is being deposited. Contact angle is defined geometrically as the angle formed by a liquid at the threephase boundary where a liquid, gas and solid intersect. If a droplet is below 10 o, then a circle fit is used for contact angle measurements instead. Dynamic contact angle measurements quantify contact angle hysteresis the difference between advancing and receding contact angles, rolloff angle and absorption which can be useful for both nonabsorbing and spongelike materials. Dataphysics oca optical contact angle measuring and. Simple and lowcost contact angle measurements using a. If the contact angle is less than 90 it is said that the liquid wets the surface, zero contact angle representing complete wetting. Arnaudov ln1, cayre oj, cohen stuart ma, stoyanov sd, paunov vn. Dynamic contact angles provide information about contact angle hysteresis, which originates from the properties that differ from the ideal surface. The optional software driven automated dispensing system is supported on all models.
All the methods are measuring advancing and receding contact angles which are used to calculate contact angle hysteresis. This instrument has been furnished with a 4 rotating wafer support stage and automated tilting base option. Onscreen protractor is a simple java application that allows to measure an angle on the screen. The authors suggest that having a standardized method for each technique would be helpful to eliminate interlaboratory variation, as would the addition of using more than one method to investigate each contact lens material. The angle formed between the liquidsolid interface and the liquidvapor interface is the contact angle. The first one is done by expanding advancing contact angle and decreasing receding contact angle the drop size with the dispenser. This software is designed to be as intuitive as possible, however we also provide guides on how to use it most effectively. Reliable surface energy measurement and a number of easytouse features make the cheminstruments camplus contact angle meter an ideal testing machine. Dynamic contact angle measurements quantify contact angle hysteresis the difference between advancing and receding contact angles, rolloff angle and absorption which can. Contact angle measurement using imaging method youtube.
Simple, accurate method for contact angle measurement tech briefs. Thetae pi acoshr, where thetae is the contact angle, h is the distance from the centre of the fitted circle to the baseline. Contact angle experiment please note that this experiment is not in the p. If you want to measure something that is small, just place it on the screen and measure it directly. The instrument of choice to measure contact angles and dynamic contact angles. The contact angle plugin is designed to provide angles for images with the. The contact angle measurement device goniometer, located in the georgia tech biocleanroom, is a software driven instrument providing automated digital contact angle measurements. Contact angle measurement with sca 20 sca 21 surface energy with the sca 21 software module the surface energy of solids can be determined by measuring multiple contact angles with different liquids. The system consists of a bespoke measurement software, usb microscope, motorized linear position slider and a sample holder with back lighting system. The optical contact angle measuring and contour analysis systems of the oca series are high precision optical measuring devices for the measurement of interfacial parameters and phenomena. Jan 14, 2010 measuring the threephase contact angle of nanoparticles at fluid interfaces. Dynamicstatic optical contact angle meter interfacial. Surftens contains surftens pd measurement of surface tenison using the pendant. As a result, the otherwise usual tracking of the sample height is no longer necessary.
With advance drop shape, we have developed a new, innovative software package for measuring contact angle and determining surface free energy sfe. New, innovative software advance drop shape for contact angle measurement intuitive user interface, powerful video analysis and a wide range of functions with advance drop shape, we have developed a new, innovative software package for measuring contact angle and determining surface free energy sfe. They are often dependant of one measurement setup, and may fail under nonstandard conditions. In addition, some of these techniques require expensive computer software to analyze the liquid interface and obtain a desirable accuracy of one percent in the measurement of contact angle. For droplets with contact angles above 10 o, a polynomial curve is fitted to the droplet edge. How can i get a good contact angle value from the dropletsample surface image. It is shown how this method can be implemented with many currentlyavailable cellphone models. Jul 19, 2016 measure the contact angle of the drop in the image e. New, innovative software advance drop shape for contact angle. This rapid and straightforward method makes the measurement of contact angles. You can measure both the length, area, circumference or angle of an object with image measurement. The sessile drop contact angle is measured by a contact angle goniometer using an optical subsystem to capture the profile of a pure liquid on a solid substrate. Contact angle measuring surface tension the contact angle is a measure of the ability of a liquid to wet the surface of a solid.
Static angle and advancing angle are quantitative measures of the wetting of a solid by the liquid, but they can also be used as a quality control measure in. In our contact angle software, the baseline is defined by the user. Thus a goniometer is a measuring device for angles. If you want to measure something bigger, you can take a picture and upload it, then move the center point of the protractor to measure its angle. How to choose contact angle meter or contact angle. The software is based on a plugin for imagej, a general purpose free imageprocessing package.
In a laboratory setting, in vitro wettability can be quantified by measuring the contact angle. Oca optical contact angle measuring and contour analysis systems. In this study, a smartphonebased contact angle measurement instrument was developed. In surface science, an instrument called a contact angle goniometer is used to measure static contact angle, advancing and receding contact angle, and in some cases, surface energy. What is the difference between static and dynamic contact angles. Pdf measuring the contact angle using imagej with contact. You cant calculate the contact angle without knowing where the droplet edge meets the baseline. Find, read and cite all the research you need on researchgate.
Unquestionably, the most accurate means of measuring the contact angle of a sessile drop is by compu. Angle measurement cnet download free software, apps. The root goni refers to angle while meter refers to measuring device. Increased accuracy can be achieved using lowcost closeup lenses and the image can be transmitted to a laptop for sub sequent processing. With advance drop shape, kruss has developed a new, innovative software package for measuring contact angle and determining surface free energy sfe. Since then oeg gmbh develops and produces iamge processing based optical measuring instruments for industry and research. The authors prefer the freelyavailable imagej software package 10 for its everexpanding flexibility. There are two methods for measuring dynamic contact angles with the attension theta optical tensiometer. Optical tensiometer contact angle meter dyne technology. William zisman of the united states naval research laboratory in washington, d. Measuring the threephase contact angle of nanoparticles at fluid interfaces. Klonk image measurement, free, software, tool, image.
Contact angle measurements using cellphone cameras to. The contact angle plugin is designed to provide angles for images with the droplets upside down. Contact angle measurement system contact angle measurement. Measuring the threephase contact angle of nanoparticles. Two different contact angle calculation methods, younglaplace and polynomial fitting methods, were implemented in this instrument. Contact angle measuring instrument dsa100 processor tensiometer k100 with care to accuracy. The angle formed at the boundary of the droplet is the contact angle, which characterizes a surfaces wettability. Contact angle measurements, by providing information on the properties of a surface, such as wettability and surface energy, are of growing importance in countless branches of science and technology. How can i get a good contact angle value from the dropletsample.
Surftens is a windows image processing software for measurement of contact angle of liquids on solids. This paper presents a contact angle measurement system developed using simple apparatus. Free software for high precision contact angle measurement. These techniques may also have difficulty measuring dynamic changes in the contact angle. When an interface exists between a liquid and a solid, the angle between the surface of the liquid and the outline of the contact surface is described as the contact angle.
The contact angle wetting angle is a measure of the wettability of a solid by a liquid. Measurements can be taken using live or still images and is designed for both macroscopic and microscopic measurement tasks. Actually, material such as fiber especially measuring contact angle between resin and single fiber, or single fiber with superhydrophobic surface, powder with contact angle above 80. This system is established with the contact angle and surface tension measurement experiment which is based on foxzisman theory. Baseline inaccuracy is the primary contributor to contact angle inaccuracy. Contact angles can be divided into static and dynamic angles. Compared with the traditional measurement instruments, this instrument has the advantage of simplicity, compact size, and portability. I used attension theta to measure the water contact angle of my sample. Contact angle goniometer, low price measurement instrument. Contact angle is a simple and yet powerful tool for characterizing threephase junctions. If we assume the drop to be spherical, the contact angle can be estimated by multiplying the angle between the base and the height of the droplet by 2.
Boeing, lockheed martin, intel, apple, formlab, government agencies and schools, snapon, mactool, msc, spi, fowler. The contact angle of a liquid drop on a solid surface is defined by the mechanical equilibrium of the drop under the action of three interfacial tensions. You can then calculate the contact angle using the formula. Static contact angle measurement involves the placement of microliter sized droplets on a sample surface. Track the development of your measurements with image measurement and generate reports to use for documentation.
Figure 5 shows a screenshot of the software measuring a droplet b. Contact angle measuring instrument dsa100 measurement with nicely deposited drops keywords. Contact angle measurement and contact angle interpretation. Refined software makes this an affordable solution to many industrial and academic measurement tasks. Measure the contact angle of the drop in the image e. Developments in opensource computer software and lowcost digital imaging devices are drivers for such a. The portable contact angle meter is a handheld nondestructive portable contact angle meter for quantifying levels of surface preparation from the lab to the factory floor. Objective to explore the concepts of surface free energy, adhesion and wetting by measuring the contact angle of a series of liquids on a polytetrafluoroethylene teflon substrate. It has manual dispensing with camera interface for measuring contact angle of liquids on solid surfaces.
This is achieved particularly quickly and easily with our dsa100. The performance of this instrument was tested first with ideal synthetic drop profiles. It is often necessary to adjust the viewing angle before measuring the contact angle. How can i get a good contact angle value from the droplet. Dyne technology offers a range of contact angle meters for surface energy testing of films or solid substrates. Pdf procedure to measure the contact angle of a liquid drop using imagej with contact angle plugin. Needle method is the first one of the optical methods. The shape of the drop is controlled by the three forces of interfacial tension. Ipic is one of the largest precision measurement tool manufacturer and importer in north america. This plugin calculates the contact angle of a drop on a flat surface using the sphere approximation theta2atan2hl and the ellipse approximation. Mar 09, 20 contact angle measurement using imaging method. The sca 20 module is the base software module that enables the measurement of contact angles. Phenomenon like spreadability, absorption, adsorption, dissolution can be studied by contact angle measurement devices.