Patent ID: 8416410
Filing Date: 2013-04-09
Classification: G01J,G01N,G02B

Abstract:
1. A method of minimizing the effect of aberration caused by a focusing lens system at a sequential plurality of image planes, thereby minimizing abeam spot size at a point whereat it impinges on an image plane, comprising the steps of: a) providing a source of electromagnetic radiation having a finite size, and a lens system located at an object distance from said source of electromagnetic radiation, such that an image of said source is formed at an image plane at an image distance from said lens system, said lens system comprising at least two groupings of lens elements, each grouping comprising a selection from the group consisting of: said lens system further comprising means for releasably securing groupings of lens elements at intended distances from one another; and said lens system allowing for adjustment of distance between at least two, of said at least two, groupings of lens elements; b) configuring the system to position said source of electromagnetic radiation at an object distance from said lens system to direct a beam thereof through said lens system and impinge at said image plane; c) adjusting the spacing between at least two, of the at least two, groupings of lens elements so that the effects of aberration, hence, spot size of the beam where it impinges on said image plane become substantially minimized and releasably securing said at least two groupings of lens elements in position; said method further comprising: d) configuring the system to position said source of electromagnetic radiation at an object distance from said lens system, which differes from that set in step b, to direct a beam thereof through said lens system and impinge at a resulting image plane; e) adjusting the spacing between at least two, of the at least two, groupings of lens elements so that the effects of aberration, hence, spot size of the beam where it impinges on a resulting image plane become substantially minimized, and releasably securing said at least two groupings of lens elements in position; wherein said spacings in steps c and e between said at least two, of the at least two groupings of lens elements different.