SOLUTION SHEETMicroLIF system

Concentration, temperature, and pH measurements inmicro scale

Dantec Dynamics MicroLIF system, displaying concentration results from a y-type micromixer

MicroLIF system for accurate scalar measurements in microscale
The all-in-one MicroLIF system comes with high magnification, high resolution, andsuperior measurement accuracy. Different illumination alternatives increase the flexibility
during experiment setup, calibration and measurements. The system is suitable both forconventional dual pulse imaging and for time resolved imaging. These make the MicroLIF
system suitable for experiments simulating biological flows, validation, and test of flows
in MEMS, design and development of Lab-on-chip devices, two-phase flow microsystems,and mixing enhancement studies.

Key benefits•

Integrated solution with safe delivery of laser light•

Optics and dyes optimized for maximum SNR•

Measurements at high optical magnification: up to 100x•

Modular system: easy upgrade to/from conventional PIV or LIF systems•

Time resolved measurements: up to 10kHz

MicroLIF and its application areas

Laser Induced Fluorescense (LIF) is now a mature technique with more than40 years of application history in fluid mechanics. In this time frame LIF has
been applied in different ways to different experiments creating various names
for the technique: Planar LIF, 3D LIF, Scanning LIF, Time-resolved LIF, Gas LIF
and Combustion LIF. MicroLIF is one variation of this technique that describes
measurement of scalar quantities, like concentration, temperature, and pH
with micron resolution. With the advances in research on micro technologies,
dispersion of species, thermal energy and acidity in micro scales has received
increased focus. MicroLIF systems are used to measure species concentration in
two-phase flow microsystems; temperature maps in micro-heat exchangers andpH maps in microreactors.

MicroLIF system optimized for high SNR

Enhanced focus on microfluidics•

The MicroLIF system is the perfect solution for performing planar scalarmeasurements in microfluidic devices. The system is optimized for highresolution, high magnification and high measurement accuracy. The all-in-one
solution consists of:•Inverted Fluorescence microscope•Laser safety systems•

Laser illumination for calibration andmeasurement•System computer and synchronizer••

CamerasSoftware (DynamicStudio)•Microchannels

With more than 65 years of experience in developing diagnostic tools for fluid
mechanics, we have developed a dedicated MicroLIF system for performing
scalar measurements in microfluidic devices. The turnkey system is optimized
for maximum light transmission and therefore for optimized signal to noise ratio(SNR). The components of the system are designed to make PIV measurements
safe and user-friendly, so that the researcher can focus on the experiment and noton the equipment or laser safety.

Overview of a MicroLIF system.

The system components
HiPerformance microscope
The microscope configuration is carefully selected and modified for therequirements of an accurate MicroPIV measurement. The HiPerformance
Microscope is an inverted fluorescense microscope that is optimized for
microfluidic applications. The microscope can be delivered with a manual XY
stage or a motorized XYZ stage. Please refer to the separate HiPerformance
Inverted Microscope Product Information for details. On request we canimplement laser delivery, including a laser safety kit, for other microscopes.
Page 2

HiPerformance microscopeFilter cubes

Schematic of optical paths in fluorescent microscopy.

In an epi-fluorescence microscope, both illumination and imaging take placethrough the microscope objective. An optical filter cube reflects the green lightfrom the laser and transmits the broadband fluorescent emission to the camera
detector. The performance of the filter cube is optimized for maximum signal
to noise ratio (SNR): The optical components in the filter cube are selected toreflect the emission wavelengths, transmit the fluorescent band produced by thefluorescent markers and block the unwanted harmonics involved in the process.

CamerasWith more than 100 different camera models supported, it is easy to pick asuitable camera for the experiment’s spatial resolution, pixel sensitivity andtemporal resolution requirements: This camera range includes CCD, CMOS andsCMOS detectors, from 2.3 to 25Mpix resolution, up to 70% absolute quantum
efficiency (QE) and up to 25600 frames per second. Different C- and F-camera
mounts are available to adapt the field of view to the detector size. Please
consult your Dantec Dynamics representative for camera selection.

HiSense Zyla camera with 60% QE.

Illumination
For MicroLIF the illumination mode is often laser illumination, as the laser lightis monochromatic and provides good control on the excitation.

Laser illumination and safety
Several high- and low-repetition rate PIV lasers are compatible with themicroscope, which can “freeze” the particle motion in a small field of view. The
low-repetition rate PIV lasers can be used for measurements in steady flows,
and the high-repetition lasers can be used for time-resolved measurementsof transient flows. The light coupling is safely achieved using a liquid lightguide. For a complete list of compatible lasers, please consult your local Dantec
Dynamics representative.
The MicroPIV system has unique laser safety features:•A flexible optical guide ensures safe delivery of laser light into the microscope•

Special laser and microscope optics block emission of invisible harmonics•

A cover plate over the translation stage reduces the amount of light above
the microscope•

An interlock system ensures that the laser light is never in the eyepieces ofthe microscope

2D microchannelThe microfluidic device has two inlets and and one outlet. There are two regions
where one can measure 2D flow fields: a Y-junction and a step. Canonical fluid
flows can be observed; i.e. channel flow, merging and separating flows or flow
upstream and downstream of the step. The channel width and depth is ~1mm,
which allows for an easy optical access even with a high viewing angle.
Page 3Standard laser safety features of theMicroPIV system: liquid light guide,
laser interlock and safety cover.

Objectives
High quality objectives are essential for recording the particle positions
accurately in PIV images. In volume illumination, the camera FOV defines themeasurement area, but it is the numerical aperture of the microscope objectivethat defines the flatness and the thickness of the measurement plane.
The microscope objectives are designed to withstand the high-energy laser
Various magnification objectives
pulses in the measurement volume. Finally, the green laser emission and broadband fluorescense emission should be transmitted with minimum loss throughthe objective. For these reasons, only high-quality dry objectives are used in ourMicroPIV systems.

Fluorescent markers

Fluorophore selection is one of the most important steps for obtaining successful MicroLIF results. First, the marker provides a strong fluorescent signal.
Second, the excitation and emission wavelengths of the dye are compatible
with the rest of the optical system, which is designed to maximise the SNR.
Finally, the optimum dye concentration is required to perform eventual LIF
calibrations. Usually Rhodamine markers are used for concentration andtemperature measurements, whereas Fluorescein is used for pH diagnostics.
Because different markers require different excitation and emission bands;
different filter cubes are used for velocity, concentration, temperature, and pH
measurements.

Software
The MicroLIF system includes a full version of DynamicStudio, which supports:• More than 100 camera models• Any illumination device through Light Source Wizard• Distributed data acquisition and distributed data storage• Easy set-up with plug-and-play connection of cameras, timer devices andother hardware•

Image Processing Library (IPL) – a comprehensive collection of advanced
image processing functions•Proper Orthogonal Decomposition (POD) – advanced energy based flow
decomposition•••

Stability analysis using Oscillating Pattern Decomposition (OPD)
Dynamic Masking addon for better accuracy in two-phase flows
MatLab link to perform end-user specified analysis routines scripted inMatLab•

Advanced graphical representation of the measured parameters without
requiring additional third-party software such as Tecplot

Concentration measurements in a
micromixer (courtesy of IMM Institut
für Mikrotechnologie, Mainz,Germany)

System computer
The MicroPIV system includes a Data Acquisition and Control System, which ispreconfigured, tested and ready to use. All necessary hardware and software
installation is performed before delivery. The system computer is from aninternational manufacturer with worldwide presence.

Technical Specifications
Objective specifications
Magnification

5x10x

20x

40x

63x

100x

Numerical aperture (NA)

0.12

0.25

0.40

0.60

0.70

0.75

Free working distance [mm]14126.9

3.3-1.9

2.6

4.7

Cover glass correction [mm]

--

0-2

0-2

0.1-1.3-

Depth of field [µm]

18.5

5.5

1.7

0.9

0.60.5Page 4

System control with DynamicStudio– the most user-friendly and comprehensive software platform for scientificimaging.

Product overview
Sampling rate

10-15Hz50-200Hz

1kHz

10kHz

Application

Concentrationor temperature analysis

Concentrationor temperature analysis.
Time resolved
measurements
in natural convection waterflows

Concentrationor temperature analysis.
Time resolved
measurements
in mediumspeed water
flows

Concentrationor temperature analysis.
Time resolved
measurements
in high speed
water flows

Laser rep. rate [Hz]10, 1550, 100 200

1000

10,000

Camera series

FlowSense EO

FlowSense CX

SpeedSense
VEO or VEO E

SpeedSensexx12 series,and xx40
seriesOrder information
Item
Microscope

Description
HiPerformance Inverted Microscope for PIV & LIF

Item no9080M0571

Motorized stage Motorized XYZ stage for HiPerformance microscope

9080M1341

4mm coupling

Laser to Liquid Light guide Coupling. Max 4 mm beam

9080M1351

6.5mm coupling

Laser to Liquid Light guide Coupling. Max 6.5 mm beam 9080M1361

Starter kit

Microfluidics starter kit

9080X2362

5x objective

Objective Lens N PLAN 5x/0.12 WD=14 mm

9138A1201

10x objective

Included in 9080M0571

20x objective

Objective Lens HCX PL x20/0.40 corr. WD=3.2-1.9 mm

9138A1203

40x objective

Objective Lens N PLAN x40/0.55 corr. WD=3.3-1.9 mm

9138A1204

63x objective

Objective Lens HCX PL x63/0.70 corr. WD=2.6-1.8 mm

9138A1205

40x objective

Objective Lens HCX PL 40X/0.60 Corr. WD=3.3-1.9 mm

9138A1213

100x objective

Objective Lens HCX PL 100X /0.60, WD=4,7 mm

9138A1214

F adapter1x F-mount adapter for 80M57 Comp. w. Cameras<100mm wide9138A1216

1x C-adapter

1x C-Mount Adaptor for 80M57

9138A1217

0.63x C-adapter

0.63x C-mount Camera Adapter

9138A1208

0.5x C-adapter

0.5x C-mount Camera adapter

9138A1209

Line targetµPIV Line Calibration Target 0.01 mm Resolution

9138A1218

Grid targetµPIV Grid Calibration Target 0.7mm & 0.07 mm Resolution

9138A1219

Solution Sheet 0549_v1 . Subject to change without notice. Copyright © 2020.
Dantec Dynamics. All Rights Reserved. www.dantecdynamics.com