Multi Wavelength Holography

With digital holographic interferometry, both the topography of the object surface and dynamic changes of the object surface can be recorded with sub-µm accuracy. The objects can be reflective or scattering. Developed by us and patent pending: a miniaturized highly stabilized digital holographic multi-wavelength sensor, which can detect 100 million measuring points within 1 second. This sensor is therefore one of the fastest sensors in the world.

The high phase sensitivity of digital holography can be used to investigate deformations and vibrations. The downstream data analysis even allows resonance oscillations in the MHz range and multimodal oscillations to be recorded over a large area with high axial and lateral resolution. As an example, a metallic disk is shown, which was excited with two resonance frequencies of 100Hz and 160Hz. The resulting deformation states can be recorded dynamically and even separated according to frequency.

Applications that result from this are:

• Measurement of the voltage response of MEMS
• Measurement of piezo actuator high frequency stimulated components
• Detection and localization of defects that are located underneath a top layer