Method of producing a diffractive optic element and the resulting element
A method of producing a diffractive optical element includes forming on a textured surface of a first substrate ( 2 ) a predetermined pattern of an ink ( 3 ) including an activator for a metallization reaction and one or more binders; causing or allowing the binder to solidify; applying a first adhesive layer ( 4 ) on top on the solidified binder and activator; securing a second substrate ( 5 ) to the adhesive layer; removing the second substrate with adhered solidified binder and activator from the first substrate; and forming a metal coating ( 10 ) onto the activator-containing regions adhered to the second substrate.
1. A method of producing a diffractive optical element, comprising forming on a textured surface of a first substrate a predetermined pattern of an ink including an activator for a metallisation reaction and one or more binders; causing or allowing the binder to solidify;
applying a first adhesive layer on top of the solidified binder and activator;
securing a second substrate to the first adhesive layer;
removing the second substrate with adhered solidified binder and activator from the first substrate; and
forming a metal coating on the activator-containing regions adhered to the second substrate.
2. A method according to claim 1 , wherein the first substrate comprises an electroformed nickel shim having an array of closely spaced parallel raised lines.
3. A method according to claim 1 , wherein the ink is applied on the textured surface of the first substrate in patternwise manner to produce the predetermined pattern.
4. A method according to claim 1 , wherein the ink is applied by a noncontact process.
5. A method according to claim 1 , wherein the ink is applied by inkjet printing.
6. A method according to claim 1 , wherein the activator comprises a catalyst or catalyst precursor for catalysing a metallisation reaction.
7. A method according to claim 1 , wherein the binder is curable.
8. A method according to claim 7 , wherein the binder comprises one or more monomers or oligomers which can polymerise or cross-link in use.
9. A method according to claim 8 , wherein the binder comprises one or more UV-curable acrylates or methacrylates.
10. A method according to claim 1 , wherein the first adhesive comprises one or more curable materials.
11. A method according to claim 10 , wherein the first adhesive comprises one or more UV-curable or thermally-curable acrylates or methacrylates.
12. A method according to claim 1 , wherein the metal coating is formed by electroless deposition.
13. A method according to claim 1 , additionally comprising applying a second adhesive layer to the metal-bearing surface of the second substrate.
14. A method according to claim 1 , further comprising securing a layer of transparent third substrate material on top of the metal coating.
15. A diffractive optical element produced by the method of claim 1 .