Theta Optical Tensiometers

Theta Optical Tensiometers

The versatile Theta Optical Tensiometer (also known as a goniometer, contact angle meter & drop shape analyser) allows highly accurate and easy characterisation of both solids and liquids. The instrument offers measurements of surface free energy, contact angle, surface tension, wettability, absorption, adsorption, cleanliness, interfacial rheology, interfacial tension, spreading and surface heterogeneity.

Theta is able to perform a complete range of automated or manual measurements which makes it a highly versatile instrument in Research, Industrial and Quality Control laboratories. Measurements include static contact angle with the sessile drop, captive bubble and meniscus methods, dynamic contact angle with the tilted drop and sessile drop methods, surface free energy, surface/interfacial tension with the pendant drop and reverse pendant drop methods, 3D surface roughness with the Fringe projection phase shifting method and interfacial dilatational rheology with the pulsating drop method.

The Theta contact angle meter enables you to choose the level of automation that you require for different applications.  Starting with a basic frame the versatility of the instrument has a high degree of modularity and an extensive range of accessories that allow you to upgrade or change the instrument as your needs evolve.  The instrument is supplied with OneAttension Software which is user-friendly and enables easy implementation of customised features and functionality for special demands.

With optional motorised sample stage, motorised vertical movement and a choice of dispensing systems, Theta can function in a fully automated mode, placing drops in predetermined locations on the substrate and measuring the contact angles.

  • Fully automatic measurements avoids user variation and saves time.
  • Select ready-made experiment recipes or create custom programs for quick and repeatable operations.
  • Automatic base line detection and drop shape fitting.
  • Contact angle on curved surfaces (circular or near-circular).
  • Flexible and programmable frame per second rate recorded by the camera.

For a breakdown on the technical specifications of the complete Theta product range, please click on the Downloads tab below.  Click on the video tab also for an overview of how the instrument works.

Theta is an advanced optical tensiometer for high accuracy and easy measurement of: –

  • 3D surface roughness – please refer to the downloads section for further information
  • static contact angle
  • dynamic contact angle
  • surface free energy
  • surface tension
  • interfacial tension
  • interfacial rheology
  • wettability
  • absorption
  • adsorption
  • spreading
  • cleanliness
  • surface heterogeneity
Measuring range0…180°, 0.01…2000 mN/m
Accuracy± 0.1°, 0.01° mN/m
Maximum sample sizeW unlimited x 95 mm x 180mm (with stage)
Frame interval0.33 ms…1000 s
Maximum resolution1981 x 1264 pixels
Field of view1.44…30mm diagonal
Max. measuring speed3009 frames/s
CameraUSB3 digital camera
Disposable tip dispensingYes
Light sourceLED based background lighting
DimensionsH 590 mm, W 200 mm, L 740 mm
Weight (basic frame)7,3 Kg
Power supply100…240 VAC
Frequency50…60 Hz


Recommended System Requirements:
2GHz processor, 2GB MB RAM, 120 GM hard disk drive*, 1024 x 768 resolution, 1 USB2 or USB3 port,  1 additional USB2 port required with 3D topography module.

* SDD hard disk (min. 500 MB/s) needed for high speed recording with high resolution.

Operating System Requirements:
Windows 7 & 8 & 10 (32 or 64 bit).



Contact our Sales Team directly to discuss your individual requirements.  See typical configurations below & refer to the product brochure.
     Dispenser     Droplet placement     Sample stage     Possible Upgrades
Auto 4     Auto, 4 liquids     Auto     Auto XYZ     Full
Auto 3 Double     Auto, 2 liquids     Auto     Auto XYZ     Full
Auto 3     Auto, 1 liquid     Auto     Auto XYZ     Full
Auto 1B Double     Auto, 2 liquids     Auto     Manual XYZ     Full
Auto 1B     Auto, 1 liquid     Auto     Manual XYZ     Full
Basic Tips Double     Auto, 2 liquids     Manual     Manual     Full
Basic Tips     Auto, 1 liquid     Manual     Manual     Full
Basic     Manual     Manual     Manual     Full



Please contact our sales team to discuss your individual requirements.

  Theta Modules and Accessories