Laser radar through the window (lrtw) coordinate correction method

A method for corrections of metrology instruments measurements of positions of points of interests measured by beams of radiation propagating through stratified media comprising following steps:

• a) definition and arrangement of at least one metrology instrument, definition of at least one point of interest, and at least one stratified medium;
• b) definition and arrangement of at least one measurement setup having the at least one metrology instrument, at least one point of interest, and at least one stratified medium having at least a portion of stratified medium arranged in between and separating the at least one metrology instrument and the at least one point of interest;
• c) determination of coordinates of a true point of interest position of the at least one point of interest;
• d) performance of ray-tracing of at least one ray lunched from that at least one metrology instrument in a direction of a choice point of interest position through at least the portion of the at least one stratified medium and determination of at least one direction of propagation of the at least one ray through the at least a portion of the at least one stratified medium;
• e) calculation of at least one path length of the at least one ray through the at least a portion of the at least one stratified medium;
• f) determination of coordinates of a current calculated point of interest position using the at least one path length and the at least one direction of propagation of the at least one ray;
• g) determination of at least one merit function value by comparing separation of the current calculated point of interest position and the true point of interest position.
• h) comparison of the at least one merit function value and at least one predetermined optimization parameter such that if the at least one predetermined optimization parameter substantially exceeds the at least one merit function value the coordinates of the current calculated point of interest position are found to represent the coordinates of an apparent point of interest position corresponding to the true point of interest position of the at least one point of interest, and if the at least one predetermined optimization parameter does not substantially exceed the at least one merit function value a choice point of interest position is updated and the steps d)-h) repeated in sequence.