Silicon Has Good transmission at 1-7um. It is widely used for 3-5um infrared windows and lens.

Monocrystalline silicon is an infrared material with excellent cost performance.It can be divided into Transmissive Grade and Mirror Grade.As a transmittance material, ocZ-SI is widely used in the mid-infrared (1-6um) band, and the infrared transmittance is more than 50%. Monocrystalline silicon can be used in a wider band (1--14um), and high purity zonal fused monocrystalline silicon (HPFZ-Si) can even be used in the far infrared band (greater than 30um).

Silicon single crystal is also an excellent laser reflector material.Compared with other mirror materials such as copper and molybdenum, silicon single crystal is the preferred substrate material for CO2 laser mirrors due to its advantages of good thermal conductivity, excellent thermal stability, low thermal expansion coefficient, relatively low density, low cost, easy precision processing and so on.

逐句翻译

Refractive index range(20℃)

Wavelength(nm)	Refractive index(n)	Wavelength(nm)	Refractive index(n)
1357	3.4975	4000	3.4257
1367.3	3.4926	4258	3.4245
1395.1	3.4929	4500	3.4236
1529.5	3.4795	5000	3.4223
1660.6	3.4696	5500	3.4213
1709.2	3.4664	6000	3.4202
1813.2	3.4608	6500	3.4195
1970.2	3.4537	7000	3.4189
2152.6	3.4476	7500	3.4186
2325.4	3.443	8000	3.4184
2714.4	3.4358	8500	3.4182
3000	3.432	10000	3.4179
3303.3	3.4297	10500	3.4178
3500	3.4284	11040	3.4176