Chalcogenide glass material

1. A chalcogenide glass material consisting of:

a glass base material, and

an antireflection film formed directly on the glass base material, wherein

the glass base material contains, in terms of % by mole, 20 to 99% Te, and

the antireflection film includes a lower-refractive index layer and a higher-refractive index layer stacked alternately one on top of another in a total of two or more layers, the higher-refractive index layer having a higher refractive index than that of the lower-refractive index layer,

a material of an outermost layer of the antireflection film, and thus also the outermost layer of the chalcogenide glass material, is at least one material selected from the group consisting of a metal oxide, hydrogenated carbon, diamond-like carbon, and ZnS, and

a material of a first layer of the antireflection film on a side facing the glass base material chalcogenide glass material is at least one material selected from the group consisting of ZnS, Ge, Si, Y 2 O 3 , TiO 2 , and HfO 2 .

2. The chalcogenide glass material according to claim 1 , wherein the glass base material contains, in terms of % by mole, 40 to 95% Te.

3. The chalcogenide glass material according to claim 1 , wherein the glass base material further contains, in terms of % by mole, 0 to 40% Ge.

4. The chalcogenide glass material according to claim 1 , wherein the glass base material further contains, in terms of % by mole, 0 to 30% Ga.

5. The chalcogenide glass material according to claim 1 , wherein the material of the outermost layer of the antireflection film is the metal oxide, and the metal oxide is at least one material selected from the group consisting of Y 2 O 3 , Al 2 O 3 , SiO, SiO 2 , MgO, TiO, TiO 2 , Ti 2 O 3 , CeO 2 , Bi 2 O 3 , and HfO 2 .

6. An optical element in which the chalcogenide glass material according to claim 1 is used.

7. An infrared sensor in which the optical element according to claim 6 is used.