Methods for forming patterns on curved surfaces

• US 9,079,349 B2
• Filed: 08/19/2014
• Issued: 07/14/2015
• Est. Priority Date: 08/19/2013
• Status: Active Grant

• Current Assignee: MicroContinuum, Inc.
• Original Assignee: MicroContinuum, Inc.
• Inventors: Slafer, W. Dennis
• Primary Examiner(s): CULBERT, ROBERTS P
• Application Number:
  US14/463,069
• Publication Number:
  US 20150048048A1
• Time in Patent Office: 329 Days
• Field of Search: 216/26
• US Class Current: 1/1
• CPC Class Codes: B29C 41/02 for making articles of definite length, i.e. discrete articles
• CPC Class Codes: B29C 41/38 Moulds, cores or other substrates
• CPC Class Codes: B29C 59/00 Surface shaping of articles, e.g. embossing; Apparatus therefor in-mould printing B29C37/0025; by using liquids B29C71/0009; by using gases without chemical reaction B29C71/009; for decorating in general B44; abrasive blasting B24C; chemical aspects C08J7/00
• CPC Class Codes: B29C 59/02 by mechanical means, e.g. pressing B29C59/007 takes precedence; embossing expanded porous articles B29C44/5627
• CPC Class Codes: B29D 11/00 Producing optical elements, e.g. lenses or prisms grinding or polishing of optical elements B24B; constructional form of optical elements G02B; optical parts of spectacles G02C7/00
• CPC Class Codes: B29D 11/00317 Production of lenses with markings or patterns
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: B29K 2101/00 Use of unspecified macromolecular compounds as moulding material use of unspecified rubbers B29K2021/00
• CPC Class Codes: B29L 2011/0016 Lenses
• CPC Class Codes: G03F 7/0002 Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping

Abstract

Methods are disclosed by which two-dimensional and three-dimensional pattern layers may be formed on non-planar surfaces, including optical elements such as lenses with one or more cylindrical, spherical or aspheric surfaces. Patterns with features in the micro- and/or nano-size regime comprised of organic, inorganic or metallic materials may be formed by the methods described herein.

Claims

1. A method for fabricating a pattern on a compound curved surface, said method comprising:

a. forming a relief pattern on a stretchable surface to form a replication mold,

b. coating a layer of curable polymer material on said stretchable surface,

c. causing said coated stretchable surface to come in conformal compliant contact with a curved substrate

d. exposing said curable polymer material to radiation to cause solidification of said polymer material,

e. withdrawing said stretchable mold from contact with said substrate so as to leave the solidified polymer having a pattern complementary to that of the relief pattern of the stretchable replication mold as a layer on the surface of said substrate.

2. The method of claim 1 in which the substrate is a lens.

3. The method of claim 1 in which the substrate is concave or convex.

4. The method of claim 1 in which the substrate is comprised of two or more curved surfaces.

5. The method of claim 1 in which the curable polymer material is applied to the substrate, the replication mold, or both.

6. The method of claim 1 in which the polymer material relief pattern is used as a resist mask.

7. The method of claim 5 in which the resist mask is used to form a pattern in an underlying material layer by etching of said underlying material.

8. The method of claim 5 in which a material layer is deposited over said pattern-forming mask followed by removal of said mask and excess deposited said material to result in the formation of a desired pattern in said material.

9. The methods of claims 7 or 8 in which the material layer is comprised of one or more metals, alloys, dielectrics or combinations thereof.

10. The methods of claims 7 or 8 in which the pattern formed in said material layer comprises a transparent conductive grid or circuit.

11. The method of claim 1 in which conformal compliance between the stretchable mold and a convex substrate is accomplished by stretching a tension hoop mounted with said stretchable mold over said convex substrate.

12. The method of claim 1 in which conformal compliance between the stretchable mold and a concave substrate is accomplished by pressing a compliant elastomeric member against the backside of said stretchable mold mounted in a tension hoop.

13. A method for fabricating a pattern on a compound curved surface, said method comprising:

a. forming a relief pattern on a stretchable surface to form a replication mold,

b. coating a layer of curable polymer material onto the relief pattern of said stretchable replication mold,

c. solidifying said layer of polymer material,

d. causing the surface of said solidified polymer layer on said stretchable surface to come into conformal compliant contact with a curved substrate

e. using an adhesive to adhere said solidified polymer layer to said curved substrate,

f. separating said stretchable replication mold from said solidified layer of polymer material so as to leave the solidified polymer having a pattern complementary to that of the relief pattern of the stretchable replication mold as a layer on the surface of said substrate.

18. The method of claim 13, wherein the pattern is a transparent electrically conductive grid.

19. The method of claim 13, wherein the stretchable replication mold is separated from the solidified layer of polymer material using differential thermal expansion and/or contraction.

14. A method for fabricating a pattern on a compound curved surface, said method comprising:

a. forming a relief pattern on a stretchable surface,

b. causing said coated stretchable surface to come in conformal compliant contact with a curved substrate

c. Using an adhesive to bond the backside of said curable polymer material to a curved substrate.

15. The method of claim 14, further comprising using an applied vacuum to produce conformal compliance between the stretchable mold and substrate.

16. The method of claim 14, wherein the pattern is a motheye antireflection pattern.

17. The method of claim 14, wherein the relief pattern on said stretchable replication mold is pre-distorted to compensate for changes in geometry caused by bringing said mold into conformal compliance with said curved substrate.