Studies on Papanicolaou staining. I. Visible-light spectra of stained cervical cells.

This paper presents visible-light absorbance spectra of the nuclei and cytoplasms of ten types of cervical cells stained by the Papanicolaou technique, together with tables summarizing the data. It is concluded that for automated image processing of Papanicolaou smears the most suitable wavelengths are 531 nm to maximize the contrast of cell against background and a wavelength in the range 560 nm to 605 nm (with a mean at 575 nm) to maximize the contrast of the nucleus against the cytoplasm.