​Biologists made the move from 2D to 3D cell culture a decade ago. However, the tools they use to observe cell cultures had not yet caught up. The lensless microscope developed in 2016 by Leti, a CEA Tech institute, has now been adapted to acquire several images from different angles to generate 3D renderings.

The microscope was modified to be able to move a full 360 degrees around the sample in the incubator, capturing up to 60 images at a rate of around one image every 30 minutes. The system then functions much like the initial lensless microscope: The signals generated when the light from the laser diode that illuminates the culture and the light diffracted by the cells are superimposed are picked up by a CMOS sensor. A new algorithm developed specifically for the modified microscope turns the series of images into a 3D moving picture of 5 mm3 of the cell culture.

The 3D images provide a more accurate picture of reality and, therefore, deliver new information on cell behavior in culture. Biologists will now be able to learn more about cell movement and self-organization in certain conditions like embryogenesis and even cancer.