Fitzpatrick, Cella, Harper & Scinto
Antireflection film and optical element coated with the antireflection film
The antireflection film of the present invention comprises an alternately multi-layered film of 10 layers formed on a base member and having antireflection characteristics in two wavelength regions including a first wavelength (&lgr;1) of 248 nm and a second wavelength (&lgr;2) of 633 nm as central wavelengths, respectively, the multi-layered film of 10 layers comprising: low-refractive index layers arranged at odd-numbered positions from a side opposite to the base member and having a refractive index of 1.45 to 1.52 at the first wavelength (&lgr;1); and high-refractive index layers arranged at even-numbered positions from the side opposite to the base member and having a refractive index of 1.65 to 1.80 at the first wavelength (&lgr;1), wherein layers arranged at the first, second and third positions from the side opposite to the base member each have an optical thickness ranging from 0.21&lgr;1 to 0.28&lgr;1.
Canon Kabushiki Kaisha
G
G02B
inventional
Kenji Yasuyuki Ryuji Hidehiro Minoru
Ando Suzuki Biro Kanazawa Otani