Replication and related methods and devices, in particular for minimizing asymmetric form errors

1. A method for manufacturing devices by replication, each of the devices comprising a device surface, the method comprising:

producing the devices from a replication material by replication using a replication tool;

wherein the replication tool comprises a tool material comprising replication sites comprising a replication surface each, wherein each of the replication surfaces corresponds to a negative of the device surface of a respective one of the devices, and wherein the tool material comprises, in addition to the replication sites, one or more mitigating features,

wherein the mitigating features comprise recesses, grooves, cuts or protrusions, and

wherein the replication sites and the mitigating features are separated by the tool material so that the replication material does not flow between the replication sites and the mitigating features during manufacturing and the devices are solely shaped by the replication sites, wherein the mitigating features are features for at least one of:

reducing a directionality of shape deviations of the replication surfaces;

reducing a directionality of shape deviations of the replication surfaces from a negative of respective desired device surface shapes;

avoiding or at least reducing asymmetric form errors of the device surfaces;

reducing a directionality of a distribution of tool material in a respective region around each of the replication sites;

increasing a uniformity of a distribution of the tool material in respective regions around each of the replication sites; and

relieving stress in the tool material.

2. The method according to claim 1 , further comprising producing the mitigating features after producing the replication surfaces, and wherein the mitigating features are features for at least one of:

for provoking at least partial reversal of an undesired deformation of the replication surfaces;

for provoking a desired deformation of the replication surfaces, wherein said desired deformation at least partially reverses a pre-existing undesired deformation of the replication surfaces.

3. The method according to claim 1 , further comprising producing the mitigating features at the time of producing the replication surfaces, and wherein the mitigating features are features for avoiding or at least reducing a deformation of the replication surfaces, wherein the method comprises producing the replication surfaces by means of shaping surfaces of a master during manufacture of the replication tool, and wherein said deformation is a deformation relative to a negative of respective shaping surfaces of the master.

4. The method according to claim 1 , wherein the replication surfaces comprise recesses in the tool material.

5. The method according to claim 1 , wherein the devices are rotationally symmetric optical devices.

6. The method according to claim 1 , wherein a lateral distribution of the replication sites has a symmetry lower than a rotational symmetry of order two, wherein the rotational symmetry is a two-fold mirror symmetry.

7. The method according to claim 1 , wherein the producing the devices by replication comprises a carrying out an embossing process.

8. The method according to claim 1 , wherein the replication tool comprises a rigid carrier to which the tool material is attached, and wherein the tool material is resilient and/or has an open-porous structure, and wherein the tool material is a silicone.

9. The method according to claim 1 , wherein the mitigating features are interspersed with the replication sites.

10. A replication tool for manufacturing devices by means of replication, the replication tool comprising

a multitude of replication sites established in a tool material of the replication tool, each of the replication sites having a replication surface having a shape corresponding to a negative of a device surface of one of the devices; and, in addition,

one or more mitigating features,

wherein the mitigating features are features for avoiding or at least reducing asymmetric form errors of the devices

wherein the mitigating features comprise recesses, grooves, cuts or protrusions, and

wherein the replication sites and the mitigating features are separated by the tool material so that the replication material does not flow between the replication sites and the mitigating features during manufacturing and the devices are solely shaped by the replication sites.

11. The replication tool according to claim 10 , wherein the replication sites are arranged on a non-square rectangular grid, and the mitigating features are interlacing the grid.

12. The replication tool according to claim 10 , wherein the replication sites are arranged in mutually parallel rows, and at least a portion of the mitigating features are arranged between neighboring ones of the rows, wherein at least a portion of the mitigating features are arranged between each pair of neighboring ones of the rows.

13. The replication tool according to claim 10 , wherein the mitigating features are located in the vicinity of each of the replication sites and are distinct from the replication surfaces and the replication sites.

14. The replication tool according to claim 10 , wherein the replication surfaces comprise recesses in the tool material, wherein the replication surfaces are concave.

15. The replication tool according to claim 10 , comprising a carrier to which the tool material is attached, wherein the carrier is stiffer than the tool material, wherein the tool material is a resilient material, wherein the tool material is a silicone.

16. The replication tool according to claim 10 , wherein the mitigating features are features for reducing asymmetric form errors of the replication surfaces.

17. The replication tool according to claim 10 , wherein the tool material has an open porous structure, wherein the tool material is a silicone.

18. The replication tool according to claim 17 , wherein the tool material is a polydimethylsiloxane.