The transmission-configured Digital Holographic Microscope (DHM®) offers a unique experimental setup for analyzing light-transmitting samples in biology and material sciences.
DHM-T combined with an electrophysiological setup. Image Credit: Park Systems
Biological Imaging
Label-Free Biological Microscopy
DHM® provides non-toxic quantitative assessments of individual cells and cultures up to confluence.
- Diagnostic
- Time-lapse
- Multi-well plate screening
Investigate Unexplored Biological Processes
DHM®’s quantitative phase measurement can be interpreted based on several biological processes.
- Intracellular concentration
- Morphology changes
- Channel activity
- Cell viability
Perform Multimodal Imaging
An optional module allows for simultaneous DHM® and fluorescence measurements.
- Correlate DHM® readings with established measurement techniques
- Use DHM to reduce the need for fluorescence labelling
- Improve understanding of cellular mechanisms
Optical Profilometry
Transmission Configured Optical Profilometer
The transmission DHM® allows for measurement of many sample attributes.
- Sample optical topography
- Variable thickness
- Refractive indices and concentrations
- Birefringence
Investigate Innovative Materials and Devices
Fast dynamical measurement has proven useful in a variety of applications.
- Wettability of coatings and structures
- Fluids and gas dynamics
- Dissolution and crystallization
- Particle velocimetry
- Micro-optics
- Micro-fluidics
- Stress and constraints analysis
- Liquid Crystal Displays (LCD)
- Biophysics
Time sequence of 3D optical map of quantitative phase measurement, limited by camera rate: division of HeLa cells. Image Credit: Park Systems
DHM®
Transmission DHM®. Image Credit: Park Systems
Digital Holographic Microscopy (DHM®) is a patented technology. The microscope uses a digital camera to capture holograms created by interference between the sample beam and an internal reference beam. The holograms are mathematically processed to produce a three-dimensional optical map of the specimen.
The laser wavelength intrinsically defines DHM®’s vertical calibration. This method produces accurate and reproducible data with interferometric (subnanometric vertical) and lateral resolution (limited by microscope objective choice).
Advanced numerical processing allows for simultaneous or post-processing of recorded holograms to achieve fine focus without human sample height adjustment.
Two Transmission DHM® configurations differ in the number of wavelengths:
- T1000 models are perfect for measuring clear material samples with flat surfaces and examining simple living cells because they are set up with a single wavelength
- T2100 models expand measurement capability by being set up to measure at two wavelengths simultaneously
Technical Specifications
Source: Park Systems
| System |
| DHM models |
T1000 |
T2100 |
| Number of laser sources |
1 |
2 |
| Operating wavelength (± 1.0 nm) |
666 nm |
666 nm, 794 nm |
| Laser wavelength stability |
0.01 nm / °C at 675 nm |
| Sample stage |
Manual or motorized XYZ stages 114 mm x 76 mm x 38 mm travel range |
| Objectives |
Magnification 1.25x to 100x, standard, high NA, long working distance, water/oil immersion |
| Objective & condenser turret |
6 positions |
| Computer |
Workstation with the latest multicore Intel® processor, high-performance graphics card, optimized and configured for DHM with a screen min 21 inch and a mouse |
| Software |
Proprietary Koala software based on C++ and .NET
Additional optional software modules aare vailable for advanced analysis |
| Data compatibility |
Measurement data recorded in bin format, exportable in .txt format, recorded and reconstructed images exportable in .tif format or .txt array |
| Performance |
| Measurement mode |
Single wavelength at 666 nm |
Short synthetic wavelength at 8 μm 4 |
| DHM models |
T1000, T2100 |
T2100 |
| Accuracy 1 [nm] |
1.04 |
1.0 / 5.04* |
| Vertical resolution 2 [nm] |
2.04 |
2.0 / 10.04* |
| Repeatability 3 [nm] |
0.024 |
0.02 / 0.054* |
| Vertical measuring range |
up to 500 μm4 |
up to 500 μm4 |
| Max. height of steps with sharp edges6 |
up to 1.0 μm4
up to 3.5 μm5 |
up to 7.0 μm4
up to 22 μm5 |
| Vertical calibration |
Determined by interferometric optical filter, ±0.1 nm |
| Acquisition time |
Standard: 500 μs (optional 10 μs) |
| Acquisition rate |
Standard: 190 fps (1024 x 1024 pixels) (optional up to 100,000 fps). |
| Reconstruction rate |
Up to 25 fps 1024 x 1024 pixels hologram (data analysis dependent) (optional up to 60 fps) |
| Lateral resolution |
Objective dependent, down to 300 nm** |
| Field of view |
Objective dependent, from 66 μm x 66 μm up to 5 mm x 5 mm** |
| Working distance |
Objective dependent, from 0.3 to 18 mm** |
| Digital focusing range |
Up to 50x depth of field (objective dependent) |
| Sample illumination |
Down to 1 μW/cm2 |
| Power requirements |
| Input voltage |
85-260 VAC – 50/60 Hz |
| Power requirements |
max. 250 W |
| Dimensions & weight |
| Dimensions (L x W x H) |
600 x 350 x 500 mm |
| Weight |
30 kg |
1 As demonstrated by taking the temporal standard deviation on 1 pixel over 30 measurements
2 Defined as twice the accuracy
3 As demonstrated by taking the one sigma Rq value of 30 repeatability measurements without sample
4 Converted value for measurements in air and with sample refractive index n = 1.5
5 Converted value for measurements in water and with sample refractive index n = 1.5
6 Depends on the laser source(s) and operating wavelength(s)
* With / Without single wavelength mapping
** Objectives specifications on www.lynceetec.com/microscope-objectives
DHM® systems are compatible with a wide variety of options.
Transmission DHM® combined with a Fluorescence module. Image Credit: Park Systems
- A dipping tip for measuring immersion in open chambers and well plates
- A fluorescence module that combines measurements of epifluorescence and DHM
- A high-speed camera to increase the range of measurements
- Goals for immersion, cover-glass correction, extra-LWD, etc
- A motorized stage for stitching and automation
- DHM automation and remote control via a remote TCP/IP module
- A stroboscopic apparatus for MEMS examination