Measuring laser beam intensity profiles and interpreting the results are the key to developing optics for high volume commercial consumer applications.  There is no room for best guesses or for interpretations, designers and integrator of laser beam shaping optics need hard facts – does it work or not. This section highlights technology used to verify results with links to equipment, techniques and some general advice.

 Laser beam shaper alignment and analysis techniques 

Paper 7062-15  
Author(s): Todd E. Lizotte, Orest Ohar, Tracie Tuttle, Hitachi Via Mechanics USA, Inc.

Abstract

Laser beam shapers challenge our sanity in new ways on a daily basis. From an industrial perspective; we design, analyze and then fabricate what is believed to be a simple solution to the complex problem of creating a uniform beam profile. Once the laser beam shaping optics are received and mounted, the task of alignment, fine tuning and measuring begins. This paper will cover methods of flat top beam shaper alignment and measurement, using various methods including beam profilometry, exposure film, and thermal paper and scanning sensor techniques. Analysis will be provided on specific measurement results relating to fabrication errors.

  
       
Beam profiling at focus: essential for beam shaping 

Paper 7062-16  
Author(s): Lawrence I. Green, Ophir-Spiricon

Abstract

Spatial laser beam profiling at focus is an essential part of quantitatively characterizing the shaped laser beam. We will discuss new methods that can profile almost any laser at almost any power level.   

 
       
Optimization of achromatic refractive laser beam shaping systems 

Paper 7062-17  
Author(s): Hagen Schimmel, LightTrans GmbH (Germany); Frank Wyrowski, Friedrich Schiller Univ. (Germany)

Abstract

Diffractive optical elements are often used in laser beam shaping systems. It is known that they are sensitive to the variation of wavelength. During the last years new design approaches of diffractive optical elements were suggested using the different dispersion characteristics of glasses. This allows the reduction of chromatic effects. Nevertheless the authors will show that especially the angular dispersion can’t be removed.
The authors will extend these suggested design methods for the optimization of refractive beam shaping elements. Again different glasses must be used to achieve an achromatization within a limited wavelength range. It will be shown that this will allow also the reduction of angular dispersion. The design approach will be demonstrated on the example of reshaping of a Gaussian intensity distribution into a circular Top Hat.

     
       
Comparison between a super Gaussian and a "true" top hat 

Paper 7062-18  
Author(s): John G. Smith, MEMS Optical, Inc.

 
Abstract

Shaping a Gaussian to a top-hat profile is actually re-mapping one functional form to another functional form such as a Gaussian to a super Gaussian. Figures of merit such as efficiency and uniformity of a super Gaussian will be compared to that of a true top-hat profile.