Micro-PIV & Micro-PTV

LaVision‘s FlowMaster Micro-PIV/PTV (µPIV/PTV) product range for velocimetry in microscopic dimensions evolved over nearly two decades and covers all needs of high-magnification flow diagnostics.
All hard- and software components are optimized for the specific requirements of microflow measurements which are different from applications in larger scales in many aspects.

Applications 

• microfluidic components
  

• lab-on-a-chip devices
  

• fuel cells
  

• membrane modules
  

• micro heat exchanger
  

• Micro-Electro-Mechanical Systems (MEMS): micro heat-sinks, micropumps, microturbines, microengines and micromixers
  

• neurobiology, cell biology, drug delivery and DNA amplification
  

• flow diagnostics of aneurysms
  

• heart valve design

A typical Micro-PIV/PTV system consists of a sensitive scientific camera, a pulsed laser with appropriate beam coupling and guiding, an epifluorescence  microscope (single channel or stereo) and our DaVis software for image acquisition, advanced analysis and intuitive visualization (with reporting and export functionality).

Making use of fluorescent seed particles is a consequence of the situation that no light sheet can be formed in such small scales and so the background and reflections from a volume illumination needs to be blocked. An epifluorescent filter cube assures that no laser light enters the viewing/imaging beampath. The measurement plane is defined by the narrow depth of focus of the microscope's objective which also has to allow for a comparably long working distance.

System Features

• application specific selection of microscope, light source and camera(s)
  

• Micro-PIV algorithm for enhanced signal-to-noise flow field imaging
  

• fiber-guided laser light delivery for standard and high repetition rate lasers
  

• microscope operation under DaVis software control
  

• time-resolved (high-speed) Micro-PIV measurements

Even the new technique of FlowMaster Shake-the-Box (4D PTV) is applicable in a microscopic stereo system overcoming the limitation of having only two perspective views. This true 3D3C volumetric measurement approach with time-resolved particle tracking enables accurate results close to surfaces or obstacles where PIV can introduce an undesired bias.

The accuracy of the Flowmaster µPIV and µPTV results in 2D and 3D are based on proven approaches from 'standard' PIV which are enhanced by some additional algorithms specific for the challenges in Micro-PIV/PTV. Image pre-processing with signal-to-noise enhancement, image dewarping for correction of optical artifacts (by patented "self-calibration") and "sum-of-correlation" are steps that allow to get highest quality results even from weak signals in scarcely seeded flows.

Upgrades

• single-channel or stereo microscopes
  

• planar 2D2C or 2D3C (stereo) PIV
  

• volumetric tomographic PIV or 4D-PTV (Shake-the-Box)
  

• motorized focus and sample stage
  

• pressure from PIV
  

• fluorescent calibration plates
  

• µPIV starter kit
  

• liquid mixing concentration or temperature fields using LIF