Purification of Te75Ga10Ge15 glass for far infrared transmitting optics for space application

TGG glass of high purity was fabricated by purification method. Aluminium used as oxygenic absorbent was added and its quantity was adjusted to meet technical specifications. The minimal optical losses measured and calculated were 0.6 dB/cm between spectral transmitting windows of 6–20 μm. Its stability was confirmed by checking characteristic temperatures and optical refractive index during a long period.