Method of manufacturing optical element

• US 5,843,321 A
• Filed: 04/19/1994
• Issued: 12/01/1998
• Est. Priority Date: 04/19/1993
• Status: Expired due to Term

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Imamura, Ayami, Kamihara, Yasuhiro, Ohashi, Hitoshi
• Primary Examiner(s): Breneman, R. B.
• Assistant Examiner(s): GOUDREAU, GEORGE A
• Application Number:
  US08/229,664
• Time in Patent Office: 1,687 Days
• Field of Search: 156/643, 156/663, 156/645, 156/632, 156/651, 156/653, 65/37, 65/38, 65/39, 65/31, 65/61, 65/102, 65/111, 216/96, 216/97, 216/88, 216/89, 216/24, 216/26, 216/52
• US Class Current: 216/26
• CPC Class Codes: C03C 15/00 Surface treatment of glass, not in the form of fibres or filaments, by etching etching or surface-brightening compositions, in general C09K13/00
• CPC Class Codes: C03C 17/06 with metals C03C17/34, C03C17/44 take precedence
• CPC Class Codes: C03C 17/25 by deposition from the liquid phase
• CPC Class Codes: C03C 17/32 with synthetic or natural resins C03C17/30 takes precedence
• CPC Class Codes: C03C 2218/113 by sol-gel processes
• CPC Class Codes: C03C 2218/328 Partly or completely removing a coating
• CPC Class Codes: G02B 5/1852 using mechanical means, e.g. ruling with diamond tool, moulding
• CPC Class Codes: G02B 5/1857 using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams

Abstract

Methods of manufacturing optical elements such as diffraction type lenses, aspherical lenses and diffraction gratings are disclosed. Deposited on a glass substrate is a workpiece film made of a material which can be machined much more easily than the substrate. Then the workpiece film is machined to form a predetermined shape or contour therein. After forming the predetermined shape or contour in the workpiece film, the workpiece film and substrate are subjected to etching to duplicate the predetermined shape or contour formed in the workpiece film into the substrate.

Claims

1. A method of manufacturing an optical element, said method comprising the steps of:

preparing a substrate having a surface;

forming a workpiece film on said surface of the substrate, said workpiece film being made of a material which is less resistant to mechanical machining than said substrate;

mechanically machining said workpiece film to form a shape or contour therein; and

etching said workpiece film and substrate to form a shape or contour in the substrate, said shape or contour formed in said substrate corresponding to said shape or contour formed in the workpiece film.

2. A method according to claim 1, wherein said workpiece film is made of a material selected from a group consisting of resin and metal.

3. A method according to claim 1, wherein said substrate is made of a glass and said workpiece film is made of a material selected from a group consisting of resin and metal.

4. A method according to claim 1, wherein said etching step is performed by an anisotropic etching.

5. A method according to claim 4, wherein said anisotropic etching is a reactive ion etching.

16. A method according to claim 1, wherein the shape or contour formed in the workpiece film is a shape or contour of a diffractive element.

17. A method according to claim 16, wherein the diffractive element is a diffractive lens.

18. A method according to claim 1, wherein the shape of contour formed in the workpiece film is a shape or contour of an aspherical lens.

22. A method according to claim 1, wherein said step of mechanically machining is performed by mechanical cutting.

6. A method of manufacturing an optical element of transmission type, said method comprising the steps of:

preparing a substrate made of a first transparent optical material and having a surface;

forming a workpiece film on said surface of the substrate, said workpiece film being made of a second transparent optical material which is less resistant to mechanical machining than said substrate; and

mechanically machining said workpiece film to form said optical element to have a shape or contour.

7. A method according to claim 6, wherein said workpiece film is made of an inorganic substance.

8. A method according to claim 7, wherein said workpiece film made of the inorganic substance is formed by a sol-gel method.

9. A method according to claim 7, wherein said workpiece film made of the inorganic substance is formed by liquid phase deposition (LPD) method.

10. A method according to claim 7, wherein said workpiece film is formed by chemical vapor deposition (CVD).

11. A method according to claim 6, wherein after the machining step, the assembly of the substrate and workpiece film is heated at a temperature higher than a room temperature.

12. A method according to claim 7, wherein after the machining step, the assembly of the substrate and workplace film is heated at a temperature higher than room temperature.

13. A method according to claim 8, wherein after the machining step, the assembly of the substrate and workplace film is heated at a temperature higher than room temperature.

14. A method according to claim 9, wherein after the machining step, the assembly of the substrate and workplace film is heated at a temperature higher than room temperature.

15. A method according to claim 10, wherein after the machining step, the assembly of the substrate and workplace film is heated at a temperature higher than room temperature.

19. A method according to claim 6, wherein the shape or contour formed in the workpiece film is a shape or contour of a diffractive element.

20. A method according to claim 19, wherein the diffractive element is a diffractive lens.

21. A method according to claim 6, wherein the shape or contour formed in the workpiece film is a shape or contour of an aspherical lens.

23. A method according to claim 6, wherein said step of mechanically machining is performed by mechanical cutting.