Real-time 3d Shape Measurement of Micro Droplet Using Digital Holographic Microscopy

This paper reports the development of a microscopic 3D shape measuring method based on digital holographic microscopy, and its application to a microscopic droplet which changes in shape as time progresses. The use of an off-axis holographic/interferometric optical system enables measuring the geometry of microscopic objects in 3D and in real time. The measurement is performed in the volume of 176 μm x 176 μm x 100 μm at 60 fps with in-plane and out-of-plane resolutions of 1.1 μm and 62 nm respectively. We have successfully measured and visualize the 3D shape of a droplet and its dynamic change.