Bio-Nanotechnology Application Laboratory

Optical Coherence Tomography#

System for Optical Coherence Tomography
© Fraunhofer IKTS
System for Optical Coherence Tomography

Optical coherence tomography (OCT) is a highly sensitive, 3D imaging technology. It uses near-infrared light to depict the internal and surface structures of various materials in high resolution.

As opposed to x-ray tomography, neither the examination object nor the source detector array has to be rotated as the OCT procedure facilitates scanning. The light scattered from the sample is recorded at individual points; each measuring point holds information about the scattering properties inside the examined object (depth scattering profile). A volumetric recording of the examination object is made possible using a raster.

The system deployed in the BNAL impresses here with its high measuring speed of 76,000 interferometric measurements per second. This means that biological samples can be recorded three-dimensionally with a resolution in the range of a few thousandths of a millimeter in just seconds. At the same time, the use of low-energy, near-infrared radiation prevents biological tissue from being influenced in any way.

Following the addition of a respective automation system, the systematic and automated recording of different cell cultures, e.g. in multi-well plates, is possible in the BNAL using OCT.


Relevant parameters


  • Measuring range: 10 x 10 x 7 mm³
  • Measuring speed: 76 kHz
  • Depth resolution (in air): 12 µm
  • Scan resolution: 13 µm


Person responsible for equipment / contact person


Dipl.-Ing. Andreas Lehmann
Fraunhofer IKTS
Department Bio- and Nanotechnology
Characterization Technologies Unit

Phone +49 351 88815-571

Multi-Acousto-Scope (MAC)#

Multi-Acousto-Scope (MAC)
© Fraunhofer IKTS
Multi-Acousto-Scope (MAC)

The MAC is a unique research microscope which combines the functionalities of optimal microscopy with those of acoustic microscopy in one single device. All of the structural requirements for the integration of photoacoustic microscopy are also met.

The combination of three microscopy techniques paves the way to innovative and correlative examination strategies. Especially beneficial is the fact that a specimen can remain in the measuring device for a variety of examinations. This allows different contrast mechanisms to be used in the same target area without the need for major alignment processes or new preparations. Examinations are therefore faster and more diagnostically conclusive.

Assembling the combi microscope on an anti-vibration table with an integrated optical breadboard enables high-contrast imaging close to the limits of resolution. The possibility of intervening in the optical beam paths is also increased.


Relevant parameters


  • Optical magnification: 5 x – 63 x
  • Mercury white light source
  • Filter sets: 49 DAPI, 38 HE eGFP and 43 HE Cy 3
  • High-resolution microscope camera: 1.4 MPixel, spectral range 350–1000 nm, max. 50 images/second
  • Acoustic resolution: approx. 1 µm
  • Frequency range: 800 MHz – 2 GHz
  • Scan mode: A, B, C images and V(z) curves
  • Photo-acoustic excitation prepared for 300-1100 nm, fiber or free-space coupling
  • Motorized transmitted light microscope table 20 x 20 mm2, precision < 1 µm
  • Anti-vibration table with optical breadboard
  • Workstation with high-resolution 24" TFT


Person responsible for equipment / contact person


Dr. Bernd Köhler
Fraunhofer IKTS
Department of Bio- and Nanotechnology
Acoustical Diagnostics Unit

Phone +49 351 88815-520