Fig. 1.

Principle of reflected beam light-sheet microscopy. A laser line is focused through the objective and is reflected from a 45° mirror side wall of a microfluidic channel. The light-sheet is reflected at the focal plane of the objective, thereby illuminating only the in-focus plane of the cell. 3D optical sectioning is achieved by moving the channel and cell up and downwards and repositioning of the light-sheet such that it is reflected at the focal plane.