Infrared ray transmissive optical member and manufacturing method thereof, optical device, and optical apparatus
An optical member made of polycrystalline silicon formed from high-purity trichlorosilane as a raw material, and that absorbs and scatters an infrared ray in a wavelength region of 4 μm or less. In the optical member, a ratio A/B between a transmittance A of an infrared ray having a wavelength of 4 μm and a transmittance B of an infrared ray having a wavelength of 10 μm is 0.9 or less, and an average crystal grain size of the polycrystalline silicon is 5 μm or less. This polycrystalline silicon is produced by hydrogen reducing SiHCI 3 by heating a base material to 800 to 900° C. using a chemical vapor deposition method. In this way, an infrared ray transmissive optical member, a manufacturing method thereof, an optical device, an infrared detector, and an optical apparatus capable of sensing a human body with high sensitivity and accuracy are realized.
1. An infrared ray transmissive optical member comprising a polycrystalline silicon formed from trichlorosilane as a raw material, the infrared ray transmissive optical member configured to absorb and scatter an infrared ray in a wavelength region of 4 μm or less whereby a ratio between a first transmittance of the infrared ray in the wavelength region of 4 μm or less and a second transmittance of an infrared ray in a wavelength region around 10 μm is less than 1.
2. The infrared ray transmissive optical member according to claim 1 , wherein a ratio A/B between a first transmittance A of a first infrared ray having a wavelength of 4 μm and a second transmittance B of a second infrared ray having a wavelength of 10 μm is 0.9 or less.
3. The infrared ray transmissive optical member according to claim 2 , wherein the trichlorosilane has a purity of 10N to 11N.
4. The infrared ray transmissive optical member according to claim 3 , wherein an average crystal grain size of said polycrystalline silicon is 5 μm or less.
5. An optical device having a principal part comprising the infrared ray transmissive optical member according to claim 2 .
6. The optical device according to claim 5 , wherein the optical device is an infrared detector.
7. An optical apparatus comprising:
first and second semiconductor lasers that emit laser light on a same optical axis;
a nonlinear optical crystal disposed on said optical axis, and into which said laser light enters; and
a filter element that filters a ray in a specific wavelength region of exiting laser light from said nonlinear optical crystal,
wherein said filter element includes the optical device according to claim 5 .
8. The infrared ray transmissive optical member according to claim 1 , wherein the trichlorosilane has a purity of 10N to 11N.
9. The infrared ray transmissive optical member according to claim 8 , wherein an average crystal grain size of said polycrystalline silicon is 5 μm or less.
10. The infrared ray transmissive optical member according to claim 1 , wherein an average crystal grain size of said polycrystalline silicon is 5 μm or less.
11. The infrared ray transmissive optical member according to claim 1 , wherein said polycrystalline silicon is a chemical vapor deposited polycrystalline silicon.
12. An optical device having a principal part comprising the infrared ray transmissive optical member according to claim 1 .
13. The optical device according to claim 12 , wherein the optical device is an infrared detector.
14. An optical apparatus comprising:
first and second semiconductor lasers that emit laser light on a same optical axis;
a nonlinear optical crystal disposed on said optical axis, and into which said laser light enters; and
a filter element that filters a ray in a specific wavelength region of exiting laser light from said nonlinear optical crystal,
wherein said filter element includes the optical device according to claim 12 .
15. An optical device having a principal part comprising the infrared ray transmissive optical member according to claim 1 .
16. The optical device according to claim 15 , wherein the optical device is an infrared detector.
17. An optical apparatus comprising:
first and second semiconductor lasers that emit laser light on a same optical axis;
a nonlinear optical crystal disposed on said optical axis, and into which said laser light enters; and
a filter element that filters a ray in a specific wavelength region of exiting laser light from said nonlinear optical crystal,
wherein said filter element includes the optical device according to claim 15 .