Fish embryo
(Top) Medake fish. (Below) Selective plane illumination microscopy (SPIM) photos of a four day old Medaka fish embryo. SPIM is able to resolve the internal structures of the organism with high resolution (better than 6 microns) as deep as 0.5 mm. The team says that this depth cannot be reached using confocal laser scanning microscopy. (Credit: EMBL)