Attension® Theta Flex is a contact angle meter that enables all measurements in one instrument for both research and quality control. It measures static and dynamic contact angle, 3D surface roughness, surface free energy, surface and interfacial tension, and interfacial rheology.

Attension Theta Flex Video

Attension Theta Flex at a glance

One instrument for all needs

All the measurements are readily included in the software. Thanks to the modular design, all applications can be fulfilled with one instrument and the instrument can be tailored for your needs.

Results you can rely on

High end imaging together with sophisticated analysis algorithms detect and analyze the contact angle and surface free energy precisely. The effect of roughness to wettability can be measured with the unique 3D Topography module.

Speed and repeatability

All steps from loading the measurement to performing it and analyzing the data can be automated. The need for time consuming preparations and cleaning are removed with the disposable liquid tips.


Optical tensiometers are used in a great variety of industries and research areas such as chemicals, pharmaceuticals, electronics, foods, energy, paper and packaging. Attension Theta Flex can be used for convenient and precise studies of:

  • Wettability
  • Adhesion
  • Homogeneity
  • Surface roughness
  • Spreading
  • Cleanliness
  • Printability
  • Adsorption
  • Emulsion and foam stability


Attension Theta Flex can perform a complete range of measurements including:

  • 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 with the sessile drop, captive bubble and meniscus methods
  • Surface- and interfacial tension with the pendant drop and reverse pendant drop methods
  • Roughness-corrected contact angle and 3D surface roughness with the Fringe projection phase shifting method
  • Interfacial dilatational rheology with the pulsating drop method

Learn more about the measurements.

OneAttension software

OneAttension features an intuitive user interface, live analysis and configurable user groups and accounts. In-depth analysis of your results takes a few seconds and data can easily be exported. Features include:

  • Fully automatic measurements avoid user dependent variation and saves time
  • Automatic base line detection and drop shape fitting
  • Batch contact angle mode for maximal throughput
  • Meniscus contact angle mode for the contact angle of fibers
  • Automatic liquid purity checkup in contact angle measurements
  • Fully automatic dynamic contact angle mode with the needle method

Modules and accessories

Attension Theta Flex enables you to choose the level of automation and the advanced functionalities that you need for your applications. With the modular design and an extensive range of modules and accessories you have room to upgrade or change the instrument as your needs evolve. Below is a selection of additional modules and accessories. For a complete list, see the Theta Flex modules and accessories brochure.

3D Topography module

Theta Flex can be combined with the unique 3D Topography module that takes the wettability and adhesion analysis into a completely new level by measuring both contact angle and surface roughness of the sample in a single measurement. Distinguish the effect of roughness on contact angle and surface free energy. Roughness measured with an external profilometer can also be entered.

Download Whitepaper: Surface roughness and wettability

High Pressure Chamber

The High Pressure Chamber is designed for wettability research within enhanced oil recovery and enables measurements at pressures up to 400 bars and temperatures up to 200°C. Integrated chamber piston and sample port are optimized for the best usability and versatility.

Pulsating Drop Module – PD200

Oscillates drop volume for interfacial rheology studies.

Picoliter Dispenser

Dispensing of picoliter-sized droplets for small sample areas and inkjet applications.

Tilting Cradle

For fully automatic dynamic contact angle measurements by the tilted drop method.

Environmental Chambers

To control the measurement environment including the temperature.


For more details about Attension Theta Flex, see the technical specifications.

Theta Range Technical Specifications


Not sure which tensiometer you need?

Use InstruMentor to find and customize your optimal instrument.

InstruMentor – Tensiometer selector

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