Patent ID: 8269955

Claim:
A system, comprising: a laser configured to produce a laser beam and to be optically coupled to a first end of an optical fiber of a device under test; a phase mask configured to selectively pass one of a plurality of modes and to be optically coupled to a second end of said optical fiber of said device under test; a detector optically coupled to said phase mask and configured to determine an intensity of said beam received over said optical connection from said phase mask; and a data analyzer connected to said detector and in selective communication with said phase mask, wherein said data analyzer is configured to: set said phase mask to selectively pass a fundamental mode, set said phase mask to selectively pass a higher order mode, receive intensity data from said detector, perform an analysis on said received intensity data, determine an analysis result indicative of an undesired mode being passed by said phase mask in addition to said mode said phase mask is set to selectively pass, send a directive to said phase mask to adjust settings of said phase mask to minimize said analysis result indicative of said undesired mode, and determine a performance in the form of at least one performance factor for said device under test according to said intensity data.