| abstract |
The optical member is made of polycrystalline silicon formulated using high-purity trichlorosilane as the starting material and absorbs/scatters infrared light in a wavelength range of 4 µm or less. More specifically, the ratio (A/B) between the transmittance (A) of infrared light at a 4 µm wavelength and the transmittance (B) of infrared light at a 10 µm wavelength is 0.9 or less. In addition, the average crystal grain size of the polycrystalline silicon is 5 µm or less. The polycrystalline silicon is produced using a chemical deposition vapor method by heating a base material to 800‑900°C and reducing SiHCl 3 with hydrogen. As a result, an infrared light-transmitting optical member capable of high-sensitivity, high-precision sensing of a human body and a manufacturing method thereof, an optical device, an infrared detector, and an optical apparatus are realized. |