Frequency Doubling Perimetry is designed to detect and diagnose glaucomatous visual field loss as well as other optic neuropathy loss in a variety of primary eye-care environments. Frequency doubling perimetry is a rapid and relatively inexpensive test that accurately detect established glaucoma. Frequency doubling perimetry is developed for screening populations for evidence of glaucomatous damage to the optic nerve. Frequency-doubling perimetry measures a function of a subset of specialized retinal ganglion cells by rapid reversal of black and white bars.