Page 59 - Chalcogenide Glasses for Infrared Optics
P. 59
Chalcogenide Glasses 37
Thermal
Coefficient
Softening Deformation of Expansion Hardness
Refractive Point Point [in/(in . °C) ¥ (Knoop
Composition Index (°C) (°C) 10 ] Scale)
6
SiAsTe 2.93 317 250 13 167
2
Si Ge As Te 3.06 320 284 10 179
3 2 5 10
GeAs Te 3.55 178 140 18 111
2 7
Ge PS 2.15 520 375 15 185
3 6
Ge PS 2.20 480 360 13 179
7 12
Ge S 2.30 420 360 14 179
2 3
Si As Te Sb 2.95 475 350 9 168
6 4 9
TABLE 2.3 Physical Constants of Chalcogenide Glasses in This Program Prepared
in Amounts Sufficient for Detailed Evaluation
FIGURE 2.9 Photograph of a large cast chalcogenide glass plate and four
glass prisms fabricated for IR index measurements.
