Target cells are thin-walled cells showing a darkly-stained center area of hemoglobin, which has been separated from the peripheral ring of hemoglobin. When viewed under the electron microscope. these cells have a cup-shaped appearance. The image on the right contains many examples of target cells, three of which are indicated by arrows.
Target cells may also be artifacts if slides dry slowly in a humid environment. If target cells are artifactual, they will probably be unevenly distributed throughout the slide so that some fields will have large numbers of cells that resemble target cells and other fields will have none or few.