Mirror substrate, mirror body using the same, and optical device using mirror body

• US 7,080,915 B2
• Filed: 04/13/2004
• Issued: 07/25/2006
• Est. Priority Date: 04/14/2003
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: Nec Toshiba Space Systems, Ltd. (NEC Corporation)
• Inventors: Ito, Yoshiyasu, Suyama, Shoko, Tsuno, Katsuhiko, Kameda, Tsuneji
• Primary Examiner(s): AMARI, ALESSANDRO V
• Application Number:
  US10/822,755
• Publication Number:
  US 20040246610A1
• Time in Patent Office: 833 Days
• Field of Search: 359/838, 359/883, 428/912.2, 428/687
• US Class Current: 359/883
• CPC Class Codes: G02B 5/08 Mirrors vehicle mirrors involving special optical features B60R1/08
• CPC Class Codes: G02B 5/0808 having a single reflecting layer G02B5/0883, G02B5/0891 take precedence
• CPC Class Codes: G02B 5/0833 comprising inorganic materials only
• CPC Class Codes: G02B 7/183 specially adapted for very large mirrors, e.g. for astronomy, or solar concentrators
• CPC Class Codes: Y10T 428/12993 Surface feature [e.g., rough, mirror]

Abstract

The present invention adopts a particle dispersed silicon material, comprising silicon carbide as dispersion particles, as a mirror substrate, subjects the mirror substrate to mirror finish polishing to form a mirror body, forms a reflecting film on the mirror body to form a mirror, and uses the mirror to form a large aperture optical system.

Claims

1. A mirror substrate, wherein the substrate is made of a particle-dispersed silicon material composed of silicon carbide and silicon, and the surface of said substrate to be used as a reflecting surface is polished to a mirror finish,

wherein the Vickers hardness of said mirror substrate is 1,500 Hv or more, the 3 point bending hardness is 500 MPa or more, and the thermal conductivity is 100 W/m-K or more.

2. The mirror substrate according to claim 1, wherein said mirror is concave.

3. The mirror substrate according to claim 1, wherein said mirror is convex.

4. The mirror substrate according to claim 1, wherein said mirror is planar.

5. The mirror substrate according to claim 1, wherein the maximum diameter of the concavities and convexities or pores on the surface of said mirror substrate is 40 nm or less.

6. The mirror substrate according to claim 1, wherein the maximum diameter of the concavities and convexities or pores is 20 nm or less.

7. The mirror substrate according to claim 5 or 6, wherein the concavities and convexities or pores on the surface of said mirror occupy 3% or less of the area of said mirror surface.

8. The mirror substrate of claim 1, further comprising a reflecting film provided on a surface of said mirror substrate.

9. The mirror substrate according to claim 8, wherein said reflecting film is made of a metal.

10. The mirror substrate according to claim 9, wherein said metal comprises gold, aluminum, silver or rhodium.

11. The mirror substrate according to claim 8, wherein said reflecting film comprises a multilayer dielectric film.

16. An optical device, wherein the mirror substrate as in any one of claims 8, 11 and 12 is employed as a reflecting mirror.

17. The optical device according to claim 16, wherein said optical device is a reflecting telescope.

18. The optical device according to claim 17, wherein the optical device comprises a mirror reflecting the incident light beam and thereafter focusing the incident light beam on a detector.

19. The optical device according to claim 17, further comprising a detector, wherein said detector of said optical device is an image sensor.

20. The optical device according to claim 16, wherein said optical device is a reflecting communication antenna.

21. The optical device according to claim 20 further comprising a detector, wherein said detector of said optical device is a photodetector.

22. The optical device according to claim 16, wherein the optical device comprises a first mirror for reflecting the incident light beam and thereafter focusing the light beam on a second mirror and the second mirror reflecting said focused light beam and thereafter focusing the light beam on a detector.

23. The optical device according to any one of claim 16, further comprising:

structural members for supporting said mirror substrate,

wherein said structural members comprise said particle dispersed silicon material composed of silicon carbide and silicon.

12. A mirror substrate, wherein the substrate is made of a particle-dispersed silicon material composed of silicon carbide and silicon, and the surface of said substrate is to be used as a reflecting surface is polished to a mirror finish,

wherein the maximum diameter of the concavities and convexities, or pores on the surface of said mirror substrate is 40 nm or less.

14. The mirror substrate according to claim 12, wherein the concavities and convexities, and pores on the surface of said mirror occupy 2% or less of the area of said mirror surface.

13. A mirror substrate made of a particle-dispersed silicon material composed of silicon carbide and silicon, and the surface of said substrate is to be used as a reflecting surface is polished to a mirror finish,

wherein a maximum diameter of concavities and convexities, or pores is 20 nm or less.

15. The mirror substrate according to claim 13 wherein the concavities and convexities, and pores on the surface of said mirror occupy 2% or less of the area of said mirror surface.