Rapid contact angle and surface tension measurements with easy, accurate analysis
Optimise inks and coatings efficiently with HD recording and intuitive PC software
The Ossila Contact Angle Goniometer provides a fast, reliable, and easy method to measure contact angles and surface tensions of liquid droplets. With its low price, compact size, and intuitive PC software - the barrier-to-entry is lowered, enabling more researchers than before to perform these useful and versatile measurements.
What is a contact angle goniometer?
A contact angle goniometer is an instrument that measures the contact angle of a droplet on a surface. This is a useful, indirect measurement of surface wetting. When a droplet starts to spread out over a surface, its contact angle becomes <90°. Complete wetting occurs when the droplet is flat, or in other words, when the droplet has a contact angle of 0°. By suspending a droplet from the tip of a needle and comparing droplet models to the image captured by the system, contact angle goniometers can also be used to perform optical tensiometry measurements.
The instrument consists of a few key components: a tilting stage, a monochromatic light source, a high resolution camera, and contact angle analysis software.
Emerging camera technologies have allowed high-resolution images to be captured for much lower material costs. This means we can reduce the price of contact angle and surface tension measurements, without compromising on quality.
Simple to Use
The system comes complete with PC software that provides a simple and intuitive interface for contact angle and surface tension measurements. We also provide user guides and videos to help you get the most out of your experiments.
The small footprint of the system lets you perform measurements in labs even when space is lacking. With a total bench area of 10 cm x 30 cm, you won't need to devote a whole desk to a single piece of equipment.
Easier Ink Optimisation
A low price and small size makes it possible for labs to have multiple systems. This enables constant access to contact angle and surface tension measurements, without needing to wait in line for a colleague to finish using it. The continuous feedback you gain from in-line measurements will speed up your ink formulation process.
Take quality videos of your droplets using the high-resolution camera and a specially selected imaging lens. Watch and edit your videos and images however you like by exporting them as .avi and .png files.
Rapid Image Capture
The high frame rate of the system allows you to study the wetting process in detail, and gain increased insight into film formation.
I use a Contact Angle Goniometer and Spin Coater from Ossila, the best tools I have ever used for the application of Perovskite solar cells. I plan to order more devices from the same brand.
Ashique Kotta, Jeonbuk National University
A high-resolution 1920 x 1080 camera captures up to 30 frames per second, which allows for in-depth analysis in the software. The manual focusing lens means that you have complete control over the sharpness of the image, simply twist the camera lens until your sample is in focus.
If file size is a concern, the software allows you to set a lower resolution or frame rate in order to save space on your hard drive.
Monochromatic light source
The powerful (mains powered) monochromatic backlight helps the software to accurately detect the edges of the droplet using a Canny edge detection algorithm.
The bright, uniform rectangular panel creates a larger change in pixel lightness than would otherwise occur, which ensures that a sharp edge can be found. This helps make contact angle and surface tension measurements quick, accurate, and reliable.
Adjustable sample stage
The adjustable sample stage makes it possible to obtain a level surface and prevent the droplet from moving during deposition. The stage can be lowered and raised without affecting the level, so it is easy to add or remove substrates between measurements and then place the platform as close to the needle as possible before starting the recording.
Should you wish to do so, the fine level of adjustment makes it possible to set a slight tilt towards the camera. This can help to align the baseline.
Syringe clamping mechanism
A versatile and adaptable clamp system is included, and can be used to secure a wide range of droplet dispensing equipment.
Included with the Ossila Contact Angle Goniometer system is a 25µl glass syringe with a removable blunt tip needle, which is ideal for dispensing droplets for both contact angle and surface tension measurements.
Intuitive PC software
The intuitive contact angle software lets you record video and perform both contact angle and surface tension measurements. The software performs edge detection on the video and uses an appropriate fitting technique to calculate the properties of the droplet, making it quick and easy to take contact angle and surface tension measurements.
The Ossila Contact Angle software is included on the supplied USB memory stick, and the latest version is always available to download for free from our website.
Contact angle measurements are a fundamental tool in researching a huge variety of topics. Almost any field of materials science can learn something from a contact angle measurement. The examples given below are just a few of the many applications that the goniometer can be used for.
Thin Film Scale-Up
For solution-processable technologies such as perovskite solar cells or OLEDs, moving from laboratory-scale device fabrication to a commercial scale is one of the great challenges in research. Scalable deposition techniques are being used to create increasingly large devices. For instance, a researcher who usually fabricates devices using a spin coater may want to create larger devices by using a slot-die coater. To do this, they will require new inks with different wettability levels. The Contact Angle Goniometer allows them to quickly identify the solutions that will wet to a substrate surface and form uniform thin-films.
When solution processing thin film electronic devices, it is common to deposit a new material layer on top of another previously-deposited layer. The choice of solvent and processing technique will determine whether or not this is possible. If the first layer in the stack can be dissolved in the same solvent as the second, damage can occur. A contact angle measurement can help you find out if the solution you deposit is penetrating the layer that it is deposited onto.
The contact angle of a droplet is partly determined by the surface on which it is deposited. The goniometer can therefore be a useful tool for determining substrate cleanliness and making sure there are no unwanted pieces of dust or dirt on the substrate. For example, when using an UV ozone cleaner to remove organic contaminants from an ITO substrate, a contact angle measurement allows you to directly measure the success of your technique.
Sometimes we do not want a solution to wet well to a surface, and coatings are developed to force a liquid to dewet upon contact. The goal of a hydrophobic coating is therefore to create a high contact angle between a liquid and a substrate. A contact angle goniometer is a required piece of equipment for studying and improving these coatings.
Getting Started with the Ossila Contact Angle Goniometer
Resources and Support
Contact Angle Goniometer
|Measurement Accuracy||± 1o|
|Measurement Range||5o - 180o|
|Overall Product Dimensions||
Width: 95 mm; Height: 165 mm; Depth: 320 mm
|Stage Area||50 mm x 50 mm|
|Maximum Sample Thickness||20 mm|
|Maximum Camera Resolution||1920 x 1080|
|Syringe Volume||25 µl|
|Needle Diameter||0.47 mm|
|Needle Length||51 mm|
The Contact Angle Goniometer comes complete with user-friendly measurement software. This software has been designed to be as intuitive as possible, but we also provide guides on how to use it most effectively. The software has two main interactive sections: recording and analysis. The analysis section allows the user to measure either the contact angle or surface tension of a droplet.
Capture high-resolution videos in the recording section of the software. The videos will automatically be saved to the destination of your choosing and are saved in .avi file format, which means you can watch them in any common video player or edit them in a video editor. When loaded into the contact angle software, the videos will appear as a series of images which can be analysed individually. The video below shows a droplet being dispensed and recorded using the Contact Angle software.
Measure contact angle and surface tension of your recorded droplets in the analysis section of the software. The software performs an edge detection algorithm on the droplet, then uses an appropriate fitting technique to calculate its properties.
For droplets with contact angles above 10o, a polynomial curve is fitted to the droplet edge. Where the curve crosses the baseline, its tangent is used to determine the contact angle. If a droplet is below 10o, then a circle fit is used for contact angle measurements instead.
The software can also perform optical tensiometry measurements on droplets suspended from a needle tip. A series of droplet models are created using the droplet radius and liquid density. The models are compared with the detected edge and the closest match is used to determine the surface tension of the liquid.
|Operating System||Windows 10 (32-bit or 64-bit)|
|CPU||Quad Core 2.5 GHz|
|Available Hard Drive Space||185 MB|
|Monitor Resolution||1920 x 1080|
To the best of our knowledge the information provided here is accurate. However, Ossila assume no liability for the accuracy of this page. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. All products are for laboratory and research and development use only, and may not be used for any other purpose including health care, pharmaceuticals, cosmetics, food or commercial applications.