Patent ID: 7515347

Claim:
A device for varying an electromagnetic radiation field in an optical spectral region, the device comprising: a first substrate with a first refractive index and a first optically functional boundary surface being at least partially curved, the electromagnetic radiation field to be varied being able to pass at least partially through said first optically functional boundary surface; a second substrate with a second refractive index and a second optically functional boundary surface being at least partially curved, the electromagnetic radiation field to be varied being able to pass at least partially through said second optically functional boundary surface after passing through said first optically functional boundary surface; a difference between said first and said second refractive indices of said first and said second substrates is smaller than a difference between each of said first and second refractive indices and a refractive index of air; said first and said second optically functional boundary surfaces being disposed on mutually facing sides of said first and said second substrates, said first and said second optically functional boundary surfaces having curvatures corresponding to one another at least in sections; and said first optically functional boundary surface and said second optically functional boundary surface defining therebetween an interspace fashioned such that when propagating from said first substrate into said second substrate through said first and said second optically functional boundary surfaces and said interspace located therebetween, the electromagnetic radiation field predominantly experiences a refraction on a basis of at least one difference in refractive index that are smaller than or equal to the difference between said first and said second refractive indices of said first and said second substrates.