Optical Tensiometer

Theta Pulsating Drop

Optical tensiometer especially suitable for interfacial rheology with the pulsating drop method.

What you can measure

Interfacial dilatational rheology
Pulsating drop method
Surface- and interfacial tension
Pendant drop and reverse pendant drop methods
Static contact angle
Sessile drop, captive bubble, and meniscus methods
Surface free energy
Sessile drop, captive bubble, and meniscus methods
Dynamic contact angle
Dynamic contact angle, advancing and receding contact angle, contact angle hysteresis, and roll-off angle
Roughness-corrected contact angle and 3D surface roughness
Fringe projection phase shifting method

A quick view

This 1-minute video will give you an overview of interfacial viscoelasticity measurements with Theta Pulsating Drop. Move to full screen for the best experience.

3 reasons to invest

Interfacial viscoelasticity with ease

Fully automatic measurements of interfacial viscosity and elasticity are user-independable and highly accurate due to automatic droplet creating and pulsation as well as due to high end imaging system.

Smarter rheology measurements

Automatic evaporation compensation keeps the droplet volume stable. Wide pulsation frequency range up to 10 Hz with reliable piezo technology. Sinusoidal, triangle, and square waveforms for wide possibilities. Temperature control option up to 250 C.

Wide research possibilities

In addition to interfacial rheology, the same system is ready for surface tension, interfacial tension, contact angle and surface free energy measurements. Handle your current and future surface science needs at once.

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A closer look

Theta Pulsating Drop is based on the extremely versatile Theta Flex optical tensiometer which is characterized by its versatility, reliability and automation. Check out the system specifications below.

	Theta Flex
Available Measurements
Static contact angle	√
Dynamic contact angle	Automatic
Surface/Interfacial tension	√
3D surface roughness	√
Interfacial rheology	√
Surface free energy	Zisman Plot, OWRK/Extended Fowkes, van Oss Acid-Base, Wu, Neumann’s Equation of State, Schultz 1 and 2
Available Measurement Methods
Sessile drop	√
Batch sessile drop	√
Captive bubble	√
Pendant drop	√
Reverse pendant drop	√
Meniscus	√
Dynamic contact angle	Automatic
Pulsating drop	√
3D Topography	√
Hardware
Measuring range (°, mN/m)	0…180, 0.01…2000
Accuracy (°, mN/m)	±0.1, ±0.01
Maximum sample size (mm)	Unlimited×100×320 (with stage)
Integrated sample holders	Yes
Frame interval	0.33 ms ... 1000 s
Maximum resolution (px)	1984×1264
Maximum measuring speed (fps)	3009
Camera	USB 3.0 digital camera with zoom
Camera protection	Inside instrument covers
Camera view angle (°)	-4.5 ... 2.5
Light source and size	LED based background lighting, 62 x 62 mm
Field of view (Ø, mm)	1.44…32.3
Measurement indicator LED	Yes
Disposable tip dispensing	√
Dimensions — Basic frame (L×W×H, mm)	765 x 230 x 435
Weight — Basic frame (kg)	26
Power supply (VAC)	100-240
Frequency (Hz)	50...60
Pulsating Drop Specifications
Perturbation principle	Piezo-electric membrane enclosed in a chamber
Frequency range	0-30 Hz(most practical range 0.01-10 Hz)
Frequency resolution	0.001 Hz
Maximum volume amplitude	~ 0.8 μl
Sample liquid volume needed	5 μl
Material	PEEK, PTFE, FPM, Titanium

	Dispenser	Droplet placement	Sample stage	Camera	Possible upgrades
Theta Flex Auto 5	Auto, 4 liquids	Auto	Auto XYZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Auto 4	Auto, 2 liquids	Auto	Auto XYZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Auto 3	Auto, 1 liquid	Auto	Auto XYZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Auto 2	Auto, 2 liquids	Auto	Auto X, Manual YZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Auto 1	Auto, 1 liquid	Auto	Manual XYZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Plus	Auto, 1 liquid	Manual	Manual XYZ	1984 × 1264 px, max 3009 FPS	Full
Theta Flex Basic	Manual	Manual	Manual XYZ	1984 × 1264 px, max 3009 FPS	Full

OneAttension Software

OneAttension software is a fine combination of a very intuitive interface and high functionality. Follow your experiment live and get the results within seconds. Let's have a look at the features! 

OneAttension Features

Automatic droplet creation, pulsation and shape analysis
Less user-dependency, more accuracy
Autonomous measurements
Set up the desired measurement parameters and the entire measurement will run automatically
Versatile pulsation features
Sinusoidal, triangle, and square waveforms. Adjustable frequency, amplitude, recording time, and settle time
Results always available
Reanalyze the results as many times as you wish. Plotting, exporting, comparing, and reporting all included
User-friendly interface
To get you going in no time
Comes with full capabilities
Every measurement mode included from interfacial rheology to interfacial tension and contact angle

Add more possibilities

Have a look at a few of the additional modules that can be used for added capabilities. You can find the full range of accessories below. 

Measuring Chamber, electrically heated, 250° C

Thermostatted electrically heated measuring chamber for temperature control up to 250 C.

Topography 3D module

The unique 3D Topography module 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.

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.

Tilting Cradle

A software controlled tilting cradle. Used for studying dynamic contact angles. Tilting range from 0 to 90° and tilting resolution 0.1°.

Picoliter Dispenser

Automated picoliter-scale drop formation. Especially for inkjet applications and for measuring contact angle on very small sample areas.

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What others say

Our instruments are present at many prestigious universities and research facilities world wide. Take a minute to find out what others say about Theta Flex.

citat8

Precision Contact Angle Meters and Tensiometers

"The ability to accurately measure contact angle as a measure of surface wettability is of utmost importance as we develop new technologies to prevent medical device-associated issues of infection and tissue trauma. The ease-of-use of the instrument and associated software is a major advantage and the support offered by the team, particularly with new applications, is exceptional.”

Queen’s University Belfast

This prestigious university in Northern Ireland is ranked amongst the top 200 in the world. Dr. Nicola J. Irwin, Lecturer in Pharmaceutical Materials Science School of Pharmacy, has been using our instrument in her work.

citat8

Ville Jokinen. Aalto University

"The ability to measure the advancing and receding contact angles with a single click and having the data into a convenient format saves time and reduces the human error."

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Aalto University, Finland

Aalto University is a top Finnish university combining science, technology and arts into a collaborative environment for both scientific communities and companies. Our contact angle meters and tensiometers have been used there in research for decades.

citat8

Researcher at MIT

“The reproducibility of the measurements acquired is excellent even with the lowest surface energy values and the tensiometers are quite flexible with regards to sample size. The software is also very useful and the customer support for the products is excellent.”

MIT, USA

MIT, Massachusetts Institute of Technology, is a world-leading research university with a mission to advance knowledge and educate students in science and technology. MIT use our tensiometers to study contact angles and interfacial energy.

Learn more

We have gathered all our in-depth knowledge associated with Theta Pulsating Drop. Browse around amongst webinars, case studies and white papers to find a topic of interest.