OSA BQ Tutorial TOPS ms

How to (Maybe) MeasureLaser Beam QualityProfessor A. E. SiegmanEdward L. Ginzton LaboratoryStanford Universitysiegman@ee.stanford.eduTutorial presentation at theOptical Society of America Annual MeetingLong Beach, California, October 1997To be published in anOSA TOPS Volume during 19981How to (Maybe) MeasureLaser Beam QualityProfessor A. E. SiegmanEdward L. Ginzton LaboratoryStanford Universitysiegman@ee.stanford.eduTutorial presented atOptical Society of America Annual MeetingLong Beach, California, October 1997AbstractThe objectives of this tutorial are to introduce the most important concepts anddefine some of the common terms involved in laser beam quality; to review brieflysome of the beam quality definitions and measurement schemes employed to date;to describe some of the problems associated with various approaches and withstandardization efforts for beam qualityt; and finally to express afew of the author’s personal prejuduces on this subject. The “Maybe” in the titleof this tutorial is intended to convey that measuring, or even rigorously defining,any single all-inclusive measure of laser beam quality is still a controversial andunsettled topic—and may remain so for some time.1. Background: Some “Ideal” Beam ProfilesTo gain some insight into the concept of laser beam quality, let us consider three elementarynear-ideal laser beam profiles such as the examples shown in Figure 1. If for example thenear-field and far-field of a uniform slit ...