In this work, a theoretical study of linear profile for graded antireflection coating has been used with silicon as substrate. A computer program has been designated using the basic equations of thin film, and the reflectance has been obtained over a wide range of wavelengths (400-1000 nm) as well as incident angles (0-60 degree)
for many film thicknesses. The film consist of hydrogenated nitrides, it was shown that the reflectance decreases as the thin film thickness increases. The reflectance reaches to less than 1% for thin film thickness 0.6 ìm.