Process of making optical zone plates

Claim 1

THE METHOD OF MAKING A ZONE PLATE WHICH COMPRISES THE STEPS OF PROVIDING A PIECE OF WIRE HAVING A DIAMETER EQUAL TO 2$F$ WHERE F EQUALS THE DESIRED FOCAL LENGTH OF THE ZONE PLATE AND $ EQUALS THE WAVE LENGTH OF THE RADIATION WITH WHICH IT IS TO BE USED, ELECTROPLATING METAL LAYERS SUCCESSIVELY ON THE WIRE HAVING OUTER DIAMETERS DETERMINED BY THE EQUATIONS: D=2$F$N, WHERE N TAKES ON THE VALUES OF SUCCESSIVE INTEGERS, STARTING WITH N=2, FOR SUCCESSIVE LAYERS, ALTERNATE OF SAID WIRE AND LAYERS BEING FORMED OF A METAL WHICH IS DISSOVLABLE IN A PREDETERMINED LIQUID AND THE REMAINDER BEING FORMED OF A METAL WHICH IS NON-DISSOLVABLE IN SAID LIQUID, CUTTING OFF A SLICE OF SAID WIRE SO PLATED, AND DISSOLVING OUT THE DISSOLVABLE METAL IN THE SLICE EXCEPT FOR THIN STRIPS OF SOLID METAL BETWEEN ALTERNATE LAYERS FOR HOLDING TOGETHER THE CONCENTRIC RINGS OF THE NONDISSOLVABLE METAL.

Claim 2

THE METHOD OF MAKING A ZONE PLATE WHICH COMPRISES THE STEPS OF PROVIDING A PIECE OF WIRE HAVING A DIAMETER EQUAL TO 2$F$ WHERE F EQUALS THE DESIRED FOCAL LENGTH OF THE ZONE PLATE AND $ EQUALS THE WAVE LENGTH OF THE RADIATION WITH WHICH IT IS TO BE USED, ELECTROPLATING METAL LAYERS SUCCESSIVELY ON THE WIRE HAVING OUTER DIAMETERS DETERMINED BY THE EQUATIONS: D=2$F$N, WHERE N TAKES ON THE VALUES OF SUCCESSIVE INTEGERS, STARTING WITH N=2, FOR SUCCESSIVE LAYERS, ALTERNATE OF SAID WIRE AND LAYERS BEING FORMED OF A METAL WHICH IS DISSOVLABLE IN A PREDETERMINED LIQUID AND THE REMAINDER BEING FORMED OF A METAL WHICH IS NON-DISSOLVABLE IN SAID LIQUID, CUTTING OFF A SLICE OF SAID WIRE SO PLATED, AND DISSOLVING OUT THE DISSOLVABLE METAL IN THE SLICE EXCEPT FOR THIN STRIPS OF SOLID METAL BETWEEN ALTERNATE LAYERS FOR HOLDING TOGETHER THE CONCENTRIC RINGS OF THE NONDISSOLVABLE METAL.