Method for fabricating mirror array for optical projection system

• US 5,085,497 A
• Filed: 03/16/1990
• Issued: 02/04/1992
• Est. Priority Date: 03/16/1990
• Status: Expired due to Fees

• Current Assignee: AURA Systems Incorporated A Corporation OFCA
• Original Assignee: Aura Systems Inc.
• Inventors: Szilagyi, Andrei, Um, Gregory
• Primary Examiner(s): Ben, Loha
• Application Number:
  US07/494,579
• Time in Patent Office: 690 Days
• Field of Search: 350/320, 350/6.1, 350/6.6, 350/486, 350/487, 350/607, 350/608, 350/609, 350/616, 350/356, 310/320, 310/311, 310/318, 310/331, 310/333
• US Class Current: 359/848
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 5/08 Mirrors vehicle mirrors involving special optical features B60R1/08
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A method for fabricating an array of mirrors for an optical projection system. This method comprises the steps of forming an array of holes between a top surface and a bottom surface on an electrically insulated substrate. These holes are then filled with an electrically conductive material. Another step in this method includes mounting a plurality of piezoelectric pedestals on the top surface of the substrate wherein each of the pedestals are disposed over a respective hole so that the first face of each of the pedestals is electrically connected to the conductive material in the respective holes. A plurality of mirrors are then mounted on the pedestals wherein each of the mirrors is disposed on at least one of the pedestals. After the mirrors are mounted the second face of each pedestal is electrically connected to a common circuit node.

Claims

1. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface in an electrically insulative substrate;

filling said holes with an electrically conductive material;

mounting a plurality of piezoelectric pedestals on said top surface of said substrate wherein each of said pedestals is disposed over a respective one of said holes so that a first face of each of said pedestals is electrically connected to said conductive material in said respective one of said holes;

mounting a plurality of mirrors on said pedestals wherein each of said mirrors is disposed on at least one of said pedestals; and

electrically connecting a second face of each of said pedestals to a common circuit node.

2. A method as set forth in claim 1, wherein said forming step includes the steps of:

masking said substrate to form a first mask on said top surface wherein said mask has a plurality of first openings therethrough, each of said openings corresponding to a respective one of said holes;

etching said substrate in areas exposed by said openings to form said holes; and

removing said mask.

3. A method as set forth in claim 2, wherein said masking step further includes the step of forming a second mask on said bottom surface wherein said second mask has a plurality of second openings, each of said openings being aligned with a respective one of said first openings, said etching step further including the step of etching said substrate in the areas exposed by said second openings.

4. A method as set forth in claim 1, wherein said forming step includes the step of drilling said holes.

5. A method as set forth in claim 1, wherein said filling step includes the steps of:

placing a metal on one of said top surface and said bottom surface of said substrate;

melting said metal so that said metal flows into said holes; and

removing said metal from said one of said top surface and said bottom surface.

6. A method as set forth in claim 1, wherein said mounting step of said pedestals includes the steps of:

mounting a piezoelectric layer on said substrate, said piezoelectric layer being coextensive with said top surface;

cutting a plurality of first parallel grooves through said piezoelectric layer, each of said first grooves being in a respective one of first interstices between parallel rows of said holes; and

cutting a plurality of second parallel grooves through said piezoelectric layer, said second grooves being orthogonal to said first grooves, each of said second grooves being in a respective one of second interstices between parallel columns of said holes.

7. A method as set forth in claim 6, wherein said mounting step of said piezoelectric layer includes the step of applying an electrically conductive epoxy between said top surface and said piezoelectric layer, said cutting step of said first grooves and said second grooves removing said epoxy from said interstices.

8. A method as set forth in claim 1, wherein said mounting step of said mirrors includes the steps of:

laying a reflective foil across said piezoelectric pedestal; and

cutting said foil in the interstices between said pedestals to form each of said mirrors.

9. A method as set forth in claim 8, wherein said laying step includes the step of precutting said foil in selected areas thereof prior to laying said foil.

10. A method as set forth in claim 1, wherein said connecting step includes the steps of:

routing a plurality of electrically conductive strips along said second face of said pedestals in parallel rows, one of said strips being used for each respective one of said rows, said strips being in electrical conduction with said second face of said pedestals; and

interconnecting each of said strips to said note.

11. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and bottom surface in an electrically insulative substrate;

filling said holes with an electrically conductive material;

mounting a plurality of piezoelectric pedestals on said top surface of said substrate wherein each of said pedestals has a first face disposed proximate to a respective one of said holes and a second face, said second face of each pedestals facing said second face of another of said pedestals;

mounting a plurality of mirrors on said pedestals wherein each of said mirrors is disposed on at least one of said pedestals;

electrically connecting said first face of each of said pedestals to said material in said respective one of said holes; and

electrically connecting said second face of each of said pedestals to a common circuit node.

12. A method as set forth in claim 11, wherein said forming step includes the steps of:

masking said substrate to form a first mask on said top surface wherein said mask has a plurality of first openings therethrough, each of said openings corresponding to a respective one of said holes;

etching said substrate in areas exposed by said openings to form said holes; and

removing said mask.

13. A method as set forth in claim 12, wherein said masking step further includes the step of forming a second mask on said bottom surface wherein said second mask has a plurality of second openings, each of said openings being aligned with a respective one of said first openings, said etching step further including the step of etching said substrate in the areas exposed by said second openings.

14. A method as set forth in claim 11, wherein said forming step includes the step of drilling said holes.

15. A method as set forth in claim 11, wherein said filling step includes the steps of:

placing a metal on one of said top surface and said bottom surface of said substrate;

melting said metal so that said metal flows into said holes; and

removing said metal from said one of said top surface and said bottom surface.

16. A method as set forth in claim 11, wherein said mounting step of said pedestals includes the steps of:

mounting a piezoelectric layer on said substrate, said piezoelectric layer being coextensive with said top surface;

cutting a plurality of first parallel grooves through said piezoelectric layer, each of said first grooves being in a respective one of first interstices between parallel rows of said holes; and

cutting a plurality of second parallel grooves through said piezoelectric layer, said second grooves being orthogonal to said first grooves, each of first alternate ones of said second grooves overlying a respective one of parallel columns of said holes and each of second grooves being alternating disposed generally midway between said first alternate ones.

17. A method as set forth in claims 11, wherein said mounting step of said mirrors includes the steps of:

mounting an optically reflective foil across said piezoelectric pedestals; and

cutting said foil in selected ones of the interstices between said pedestals to form each of said mirrors.

18. A method as set forth in claim 17, wherein said laying step includes the step of precutting said foil in selected areas thereof prior to laying said foil.

19. A method as set forth in claim 11, wherein said electrically connecting step of said first face includes the steps of:

metallizing said first face of said pedestals and second top surface along parallel columns; and

patterning to extend only between each first said selected one of said holes.

20. A method as set forth in claim 11, wherein said electrically connecting step of said second face includes the steps of:

metallizing said second face of said pedestals and said top surface along parallel columns;

interconnecting metal in each of said columns to said node.

21. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of an electrically insulative substrate;

filling said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said material electrically contacting said layer;

cutting a plurality of first parallel grooves completely through said piezoelectric layer, each of said first grooves being in a respective one of first interstices between rows of said holes;

cutting a plurality of second parallel grooves completely through said piezoelectric layer, each of said second grooves being in a respective one of second interstices between columns of said holes, said cutting of said first grooves and said second grooves patterning said piezoelectric layer into a plurality of pedestals wherein each of said pedestals has a first face electrically connected to said conductive material in a respective one of said holes and a second face opposite said first face;

placing a relatively flexible optically reflective foil on said piezoelectric layer, said foil having rows and columns of precut perforations, each of said rows of said precut perforations being generally disposed along a center line of a respective one of said first grooves, each of said columns of said precut perforations being generally disposed along a center line of a respective one of said second grooves;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective one of said pedestals wherein each of opposite ends of said mirrors overly one of said second grooves and a middle portion of said mirror is mounted to said respective one of said pedestals; and

electrically connecting said second face of each of said pedestals to a common circuit node.

22. A method as set forth in claim 21, wherein said holes are disposed in equally spaced columns and in equally spaced rows.

23. A method as set forth in claim 21, wherein said first grooves are relatively narrow and said second grooves are relatively wide.

24. A method as set forth in claim 21, wherein said mounting step of said layer includes the step of applying an electrically conductive epoxy between said top surface and said layer, cutting step of said first and second grooves removing said epoxy from said first and second interstices.

25. A method as set forth in claim 24, further comprising the steps of:

metallizing a first face of said layer prior to said mounting to said substrate, said cutting of said first and said second grooves further removing metal therefrom so that metal remains only on said first face of said pedestal.

26. A method as set forth in claim 21, wherein said mounting of said foil includes applying an electrically conductive epoxy between said second face of said pedestals and said foil.

27. A method as set forth in claim 26, wherein said electrically connecting step includes the step of placing a plurality of electrically conductive strips across said second face of said pedestals, each of said strips being disposed across a respective one of columns of said pedestals and being affixed thereto by said epoxy.

28. A method as set forth in claim 27, further comprising the step of:

metallizing a second face of said layer prior to said mounting step of said substrate, said cutting step of said first and second grooves further removing metal therefrom so that metal remains only on said second face of said pedestals.

29. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of an electrically insulative substrate wherein said holes are formed in spaced apart pairs along each row of said holes, said spaced apart paris being aligned in columns;

filling said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said material electrically contacting said layer;

cutting a plurality of first parallel grooves completely through said layer, each of said first grooves being in a respective one of first interstices between columns of said holes wherein said first interstices are within said pairs of holes;

cutting a plurality of second parallel grooves orthogonal to said first grooves completely through said layer, each of said second grooves being in a respective one of second interstices between rows of said holes;

cutting a plurality of third parallel grooves parallel to said first grooves completely through said layer, third grooves being in a respective one of third interstices between columns of said holes wherein said third interstices are between said pairs of holes, said first, second and third grooves patterning said layer into a plurality of spaced apart pairs of piezoelectric pedestals, each of said spaced apart pairs of pedestals being associated with a respective one of said spaced apart pairs of holes, each of said pedestals being disposed over a respective one of said holes and having a first face in electrical contact with said material in said respective one of said holes, and a second face opposite said first face;

mounting a relatively rigid optically reflective foil on said piezoelectric layer, said foil having rows and columns of precut perforations, each of said rows of perforations being positioned over a respective one of said second grooves and each of said columns of perforations being positioned over a respective one of said third grooves;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective one of said spaced apart pairs of piezoelectric pedestals with each opposing end portion of said mirrors being disposed on said second face of a respective one of said pedestals in each of said pairs of pedestals and further with a middle portion disposed over a respective one of said first grooves; and

electrically connecting said second face of said pedestals to a common circuit node.

30. A method as set forth in claim 29, wherein said rows of holes are equally spaced from each other and said columns of spaced apart pairs of holes are equally spaced from each other.

31. A method as set forth in claim 29, wherein said first grooves are relatively wide and said second and said third grooves are relatively narrow.

32. A method as set forth in claim 29, wherein said mounting step of said layer includes the step of applying an electrically conductive epoxy between said top surface and said layer, each cutting of said first, said second and said third grooves removing said epoxy from said first, said second and said third interstices.

33. A method as set forth in claim 32, further comprising the step of:

metallizing a first face of said layer prior to said mounting to said substrate, said cutting of said first, said second and said third grooves further removing metal therefrom so that metal remains on said first face of said pedestals.

34. A method as set forth in claim 29, wherein said mounting step of said foil includes the step of applying an electrically conductive epoxy between said second face of said pedestals and said foil.

35. A method is set forth in claim 34, wherein said electrically connecting step includes the step of placing a plurality of electrically conductive strips across said second face of selected ones of said pedestals, said selected ones being disposed in selected columns of said pedestals with one of said pedestals from each of said spaced apart pairs of said pedestals being in said selected columns, said strips being further affixed thereto by said epoxy, said foil further being electrically conductive to connect electrically said second face of each of said pedestals in each of said pairs to each other.

36. A method as set forth in claim 35, further comprising the step of:

metallizing a second face of said layer prior to said mounting step of said substrate, said cutting step of said first, said second and said third grooves further removing metal therefrom so that metal remains only on said second face of said pedestals.

37. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of a substrate;

filling each of said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said conductive material in each of said holes electrically contacting said layer, said layer being attached to said substrate at a plurality of locations wherein each of said locations is proximate a respective one of said holes;

cutting a plurality of first parallel grooves completely through said layer, each of said first grooves being in a respective one of first interstices between said rows of holes;

cutting a plurality of second parallel grooves orthogonal to said first grooves completely through said layer, each of said second grooves being in a respective one of second interstices between said columns of said holes, said cutting of said first grooves and said second grooves patterning said layer into a plurality of piezoelectric pedestals, each of said pedestals having a first face in electrical contact with said material in a respective one of said holes and a second face opposite said first face;

mounting a relatively flexible optically reflective foil on said piezoelectric layer, said foil having precut rows and columns of perforations, said foil being mounted to said layer adjacent said columns of perforations;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective one of said pedestals and generally coextensive therewith wherein opposite edge portions of each mirrors are mounted to said respective one of said pedestals; and

electrically connecting said second face of said pedestals to a common circuit node.

38. A method as set forth in claim 37, wherein said holes are disposed in equally spaced columns and in equally spaced rows.

39. A method as set forth in claim 37, wherein said first grooves and said second grooves are relatively narrow and are substantially of the same width.

40. A method as set forth in claim 37, wherein said mounting step of said layer includes the step of applying a plurality of strips of an electrically conductive epoxy between said top surface and said layer, each of said strips being disposed over a respective one of said columns of said holes, each cutting step of said first and said second grooves removing said epoxy from said first and said second interstices.

41. A method as set forth in claim 40, further comprising the step of:

metallizing a first face of said layer prior to said mounting step of said substrate, said cutting step of said first and said second grooves further removing metal therefrom so that metal remains only on said first face of said pedestals.

42. A method as set forth in claim 37, wherein said mounting step of said foil includes the step of applying a plurality of strips of epoxy along said second face of each of said pedestals adjacent said second grooves.

43. A method as set forth in claim 37, wherein said electrically connecting step includes the steps of placing a plurality of electrically conductive strips across said second face of said pedestals, each of said strips being disposed across a respective one of columns of said pedestals;

and

affixing said strips to said second face of said pedestals by an electrical conductive epoxy.

44. A method as set forth in claim 43, further comprising the step of:

metallizing a second face of said layer prior to said mounting step of said substrate, said cutting step of said first and second grooves further removing metal therefrom so that metal remains only on said second face of said pedestals.

45. A method as set forth in claim 37, wherein said foil further has a plurality of elongated channels on an underside thereof, each of said channels being alternating disposed between said columns of perforations to facilitate bending of said mirror.

46. A method for fabricating a mirror array for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of a substrate wherein said holes are in equally spaced rows and equally spaced columns and further wherein each of said columns of said holes contains a pair of closely spaced holes at each row;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said layer being mounted along first parallel narrow strips on said top surface wherein said strips are parallel to said columns, each of said strips being disposed adjacent both sides of each pair of said holes and separated therefrom by a distance generally one-fourth of the distance between each pair of holes in each row;

cutting a plurality of first parallel grooves completely through said piezoelectric layer, each of said first grooves being in a respective one of first interstices between said rows of said holes;

cutting a plurality of second parallel grooves orthogonal to said first grooves completely through said piezoelectric layer, first alternate ones of said second grooves being over a respective one of said columns of said holes, second alternate ones of said second grooves being alternating disposed substantially midway between said first alternate ones, said cutting of said first and said second grooves patterning said piezoelectric layer into a plurality of pedestals bonded substantially along a center line thereof to said substrate by said narrow strips, said pedestals each having first and second faces;

mounting a relatively flexible optically reflecting foil on said second face, said foil having rows and columns of precut perforations, said foil being mounted to said layer adjacent said columns of perforations;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective one of said pedestals wherein opposite edge portions are bonded thereto, first alternate ones of said second grooves exposing said conductive material in said columns of said holes, second alternate ones of said grooves each being substantially midway between said columns of said holes;

electrically connecting said first face of each of said pedestals to said electrically conductive material in an adjacent one of said holes; and

electrically connecting said metal in said second alternate ones to a common circuit node.

47. A method as set forth in claim 46, wherein said first grooves and said second grooves are relatively narrow and of substantially equal width.

48. A method as set forth in claim 46, wherein mounting step of said layer includes the step of applying a glue between said top surface and said layer along each of said strips, said cutting step of said first grooves removing said glue therefrom.

49. A method as set forth in claim 46, wherein mounting step of said foil includes the steps of:

applying strips of glue along edges of each of said pedestals wherein said edges are adjacent said second grooves; and

placing said foil on said pedestals.

50. A method as set forth in claim 46, wherein said foil further includes a plurality of channels on an underside thereof, each of said channels being alternating disposed between said columns of perforations.

51. A method as set forth in claim 46, wherein said step of electrically connecting said first face includes the steps of:

metallizing first alternative ones of said second grooves wherein said first alternative ones expose said holes; and

patterning metal in said first alternate ones to connect said first face of each of said pedestals to said electrically conductive material in an adjacent one of said holes.

52. A method as set forth in claim 51, wherein said step of electrically connecting said metal includes the steps of:

metallizing second alternate ones of said second grooves, said second alternate ones being alternatingly disposed between said first alternate ones; and

electrically connecting metal in said second alternate ones to said common circuit node.

57. A method as set forth in claim 50, further comprising the step of:

metallizing a first face of said layer prior to said mounting step of said substrate, said cutting step of said first, said second and said third grooves further removing metal therefrom so that metal remains only on said first face of said pedestals.

53. A method for fabricating a mirror array for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of an electrically insulative substrate wherein said holes are grouped in triplets along each row of said holes, said triplets being aligned in columns;

filling said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said material being in electrical contact with said layer;

cutting a plurality of first parallel grooves completely through said layer, each of said first grooves being in a respective one of said first interstices between columns of said holes wherein said first interstices are between columns of said triplets;

cutting a plurality of second parallel grooves parallel to said first grooves completely through said layer, each of said second grooves being in a respective one of second interstices between columns of said holes wherein said second interstices are within said triplets of holes;

cutting a plurality of third parallel grooves orthogonal to said first grooves completely through said layer, each of said third grooves being in a respective one of third interstices between rows of said holes, said cutting of said first, second and third grooves patterning said layer into a plurality of piezoelectric pedestals wherein each of said pedestals has a first face in electrical contact with said material in a respective one of said holes, and a second face opposite said first face;

mounting a relatively rigid optically reflective foil on said piezoelectric layer, said foil having rows and columns of precut perforations, each of said rows of perforations being positioned over a respective one of said third grooves and each of said columns of perforations being disposed over a respective one of said first grooves;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective triplet of said pedestals, each triplet being associated with a respective one of said triplets of said holes; and

electrically connecting said second face of each of said pedestals to a common circuit node.

54. A method as set forth in claim 53, wherein each row of said holes is equally spaced from each other and said holes in each of said triplets are separated by a first distance and said holes in adjacent triplets are separated by a second distance.

55. A method as set forth in claim 53, wherein said first and said third grooves are relatively narrow and said second grooves are relatively wide.

56. A method as set forth in claim 53, wherein said mounting step of said layer includes the step of applying an electrically conductive epoxy between said top surface and said layer, each cutting step of said first, second and said third grooves removing said epoxy from said interstices.

58. A method as set forth in claim 53, wherein said mounting step of said foil includes the step of applying an electrically conductive epoxy between said second face of said pedestals and said foil.

59. A method as set forth in claim 58, wherein said step of electrically connecting includes the step of placing a plurality of electrically conductive strips across said second face of selected ones of said pedestals, said selected ones being disposed on selected columns of said pedestals with one of said pedestals from each of said triplets being in said selected columns, said strips being further affixed thereto by said epoxy, said foil further being electrically conductive to connect electrically said second face of each of said pedestals of each of said triplets to each other.

60. A method as set forth in claim 59, further comprising the step of:

metallizing a second face of said layer prior to said mounting to said substrate, said cutting of said first, said second and said third grooves further removing metal therefrom so that metal remains on said second face of said pedestals.

61. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface in an electrically insulative substrate;

filling said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface;

cutting a plurality of first parallel grooves completely through said layer, each of said first grooves being in a respective one of first interstices between rows of said holes;

cutting a plurality of second parallel grooves orthogonal to said first grooves completely through said layer, each of said second grooves being over a respective one column of said holes;

cutting a plurality of third parallel grooves orthogonal to said first grooves completely through said layer, said third grooves being alternatingly disposed substantially midway between said second grooves, said cutting of said first, second and third grooves patterning said layer into a plurality of pedestals wherein rows of said pedestals are arranged in spaced apart pairs, each of said holes being disposed intermediate said pedestals in a respective one of said spaced apart pairs;

mounting a relatively rigid, optically reflective foil to said layer, said foil having rows and columns of precut perforations, each of said rows of said perforations being disposed over a respective one of said first grooves and each of said columns of perforations being disposed over a respective one of said third grooves;

cutting said foil along said perforations to form a plurality of mirrors, each of said mirrors being disposed on a respective one of said spaced apart pairs with opposing end portions mounted to said second face of said pedestals in each of said pairs and a middle portion disposed over one of said second grooves;

electrically connecting a first face of each of said pedestals to said conductive material in an adjacent one of said holes; and

electrically connecting a second face opposite of said first face of each of said pedestals to a common circuit node.

62. A method as set forth in claim 61, wherein said holes are disposed in equally spaced rows and in equally spaced columns.

63. A method as set forth in claim 61, wherein said first and said third grooves are relatively narrow and said second grooves are relatively wide.

64. A method as set forth in claim 61, wherein said mounting step of said layer includes the step of applying a glue between said top surface and said layer, said cutting step of said first, said second and said third grooves removing said glue therefrom.

65. A method as set forth in claim 61, wherein said mounting step of said foil includes the steps of:

applying strips of glue along the edges of each of said pedestals; and

placing said foil on said pedestals.

66. A method as set forth in claim 65, wherein said foil further includes a plurality of channels on an underside thereof, each of said channels being alternatingly disposed between said columns of perforations.

67. A method as set forth in claim 61, wherein said step of electrically connecting said first face includes the steps of:

metallizing said second grooves so that metal coats a first face of each of said pedestals and said top surface exposed by said second grooves; and

patterning said metal in said second grooves to connect said first face of each of said pedestals to said conductive material in an adjacent one of said holes.

68. A method as set forth in claim 61, wherein said step of electrically connecting said second face includes the steps of:

metallizing said third grooves so that metal coats a second face opposite said first face of each of said pedestals and said top surface exposed by said third grooves; and

electrically connecting metal in said third grooves to said common circuit node.

69. A method for fabricating an array of mirrors for an optical projection system, said method comprising the steps of:

forming an array of holes between a top surface and a bottom surface of an electrically insulative substrate;

filling said holes with an electrically conductive material;

mounting a piezoelectric layer on said substrate, said layer being generally coextensive with said top surface, said material electrically contacting said layer;

cutting a plurality of narrow first grooves completely through said layer, each of said first grooves being in a respective one of first interstices between rows of said holes;

cutting a plurality of wide second grooves completely through said layer, each of said second grooves being in a respective one of second interstices between columns of said holes, said cutting of said first and second grooves patterning said layer into a plurality of pedestals, each of said pedestals having a first face electrically contacting said material and a respective one of said holes and a second face opposite said first face;

mounting a relatively flexible, optically reflective foil on said layer, said foil having rows and columns of precut perforations, each of said rows of perforations being over a respective one of said first grooves and each of said columns of said perforations being over a respective one of said second grooves, and further proximate an edge of said second grooves;

cutting said foil at said perforations to form a plurality of mirrors, each of said mirrors having a first portion disposed on a respective one of said pedestals and a second portion overlying one of said second grooves; and

electrically connecting said second face of each of said pedestals to a common circuit node.

70. A method as set forth in claim 69, wherein said holes are in equally spaced rows and in equally spaced columns.

71. A method as set forth in claim 69, wherein said mounting step of said layer to said substrate includes the step of applying an electrically conductive epoxy between said top surface and said layer, said cutting step of said first and said second grooves removing said epoxy from said interstices.

72. A method as set forth in claim 71, further comprising the steps of:

metallizing a first face of said layer prior to said mounting step of said substrate, said cutting step of said first and said second grooves removing metal therefrom so that metal remains on said first face of said pedestals.

73. A method as set forth in claim 69, wherein mounting step of said foil includes the step of applying an electrically conductive epoxy between said second face of said pedestals and said foil.

74. A method as set forth in claim 73, wherein said step of electrically connecting includes the steps of:

placing a plurality of conductive strips across said second face of said pedestals, each of said strips being disposed across a respective one of columns of said pedestals and being affixed thereto by said epoxy; and

electrically connecting each of said strips to said common circuit node.

75. A method as set forth in claim 74, further comprising the step of:

metallizing second face of said layer prior to said cutting of said first and said second grooves so that metal remains on said second face of said pedestals.