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Exciplex-based planar fluorescence technique was applied for two-dimensional visualization of the fuel spray including the region close to the nozzle tip. A spray doped with small amount of naphthalene and TMPD was discharged from a diesel nozzle into a pressurized gaseous nitrogen inside the test chamber installed with glass windows. The fuel spray was also allowed to evaporate in high temperature gaseous environments produced by combustion of the homogeneous mixture of methane and air in the test chamber. Photographs of the temporally frozen two dimensional image of the fuel spray were processed using an image analyzer. The image in the longitudinal cross section passing through the center axis of the spray demonstrated that the high density portion of liquid fuel appeared almost periodically downstream and that the axial distance between the neighboring high density portion increased with an increase in the downstream distance.