Fig. 1.

Experimental setup to image encapsulated spheroids. A spatially and temporally incoherent light source is imaged at the back focal plane BF of two identical microscope objectives using an illumination lens. The spatial extend of the source generates small and isotropic (1μm³) observation volumes (voxel) from which light is backscattered and interferes with the beam reflected by a silicon reference mirror. Encapsulated spheroids are mechanically stabilized in an agarose gel, and maintained at 37°C temperature via an active temperature control performed at the lower glass side, which is coated with ITO.