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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. At this critical juncture the most subtle changes in fabrication and
design, either within a single diced wafer of elements (brothers & sisters) or from batch
to batch, tend to demonstrate that small changes can greatly change the conditions or
state of affairs that previously existed for alignment and performance. Once variations are
detected it is up to quality assurance and manufacturing to identify these problems and
figure how they came into existence. These slight variations which randomly materialize
influence our ability to align and measure the true performance of laser beam shaping
optical systems. Various alignment and beam shape measurement techniques are needed to ensure that the laser beam shaper is properly aligned and true performance is assessed. From an industrial perspective, it is important to rapidly understand how these variations in performance relate to the actual design, fabrication and possibly alignment errors. In many cases these variations are within the general tolerances of the fabrication process, so alignment and measurement analysis must be done to determine at what point these subtle variations exceed acceptable limits of performance. This paper will cover methods of flat top beam shaper alignment and measurement, using various tools including beam profilometry, exposure film, fluorescent media, and thermal paper and scanning sensor techniques. Analysis will be provided on specific measurement results related to fabrication errors within the beam shaping element.
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