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An idea of πShaper
operation is illustrated at the left picture. Gaussian intensity
distribution of TEMoo laser beam is converted to a flat-top
distribution (similar to a Greek letter π
) that stays invariable over a long distance.
πShaper
relates to so called refractive field mapping systems, where
the intensity profile is transformed in a control manner.
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Sure the technology of energy conversion make it
possible to create almost arbitrary intensity distribution of output
beam providing adaptation to a particular application. However, very
often just flat-top distribution is required, that is why as a standard
the πShaper
provides flattop.
A main benefit from using πShaper
is saving of laser energy that is very important in many laser applications,
especially in material processing. The problem is that Gauss intensity
distribution isn't an optimum one in many cases. For example, while
materials treating a great part of energy concentrated far from a middle
of TEMoo laser beam is not used to get a proper treating effect, most
often it is considered as a loss of energy. From this point of view
evaluation of the efficiency of using laser energy has a great importance.
As a first approach it could be done with taking into account geometrical
issues only, without effects accompanying laser treatment of materials
like burning, etc. At a figure below one can see Gauss intensity distribution
in a section of laser beam where Ih is a level of energy when an effect
of material treatment happens. "The energy figure" of laser beam has
three parts:
- E1
- an apex of Gauss is an excess of energy
over the working level Ih,
- E2
- "tails" of Gauss that almost always are losses of energy, and
- E3
- effective "cylinder" of energy.
Results of calculations for "parts of energy" are presented
at right figure.
These results seem to be very interesting. The
unconditional energy loss E2,
"tails", can reach very high level, for example, if a working energy
level is a half of maximum (very often just this level is considered
as a working one) the energy losses are 50% of full laser beam energy!
In case of laser technologies of treatment of thin films of material
the energy part E1,
"apex of Gauss", is also considered as a loss of energy since this
part exceeds the working energy level Ih, thus both energy parts E1
and E2 represent
losses. Sum of losses E1 + E2
is shown as a graph at the diagram as well; minimum of this function
is 0,63. In other words, when treating of thin films in the best case
"only" 63% of energy is lost and 37% is effective!
Sure, this is geometrical interpretation only, however this approach
makes it possible to evaluate amount of losses of laser radiation,
they could reach, sometimes, a half of total laser energy! While applying
technologies of beam shaping it is possible to improve substantially
the efficiency of using the laser energy, as well as to reach some
additional effects of laser materials treatment.
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An illustration of the πShaper
influence on the results of material processing with using
the laser is presented at left picture. Here one can see a
comparison of engraving of a depression in a material with
pure TEMoo laser as well as with the same laser but with a
πShaper after it.
Difference is evident - irregular shape of
the depression with a ragged unwished hole in the middle in
case of direct engraving with the TEMoo laser, good shaped
round depression with a controlled depth when applying the
πShaper.
This is only one example of positive effect
of applying the πShaper,
there is a plenty of laser applications, however, where this
unique tool can improve their performance providing a higher
level of stability and predictability of a technological process.
πShaper
is looking forward to your application!
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Full publication about energy saving is here(PDF, 141 KB)
Beam
Shaping? Easy! Article in "Industrial Laser
Solutions", July 2006 (PDF, 1,75 MB)
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