Painfree efficient and precise laser ablation of dental decay using a femtosecond laser

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• - Pain-free efficient and precise laser ablation
  of dental decay using a femtosecond laser
• Projects investigating acid resistance of laser
  treated teeth and dental handpiece
• development

Ablated craters in teeth, different power and
pulses
Femtosecond-pulsed laser sources cause minimal
damage to surrounding tooth material with
potential for highly precise treatment of dental
caries.
A portion of a tooth ablated by the femtosecond
laser. Note the sharp edge and minimal surface
damage.
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• Use a crystalline laser to produce microwaves
• Two optical frequencies are generated in the
  laser as the optical carrier waves
• the microwaves are obtained by mixing the
  optical signals
• The interaction of the two optical frequencies
  in the laser material controls the
• efficiency of the process

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MACQUARIE UNIVERSITY, DEPARTMENT OF
PHYSICS RESEARCH Random Lasers

• Maybe a laser doesnt have to have two mirrors
  with a gain material in between
• Random lasers use laser materials with lots of
  particles to scatter the light in random
  directions
• These can produce lasers within very thin films
  and with random directions
• We are coupling these with surface plasmons to
  improve propagation of surface plasmons

A/Prof Judith Dawes,Judith_at_ics.mq.edu.au, Tel
02 9850 8903ARC Centre of Excellence
(CUDOS_at_MQ)Centre for Lasers and Applications,
Department of Physics
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• Crystals grown in a furnace from molten
  mixtures, creating a thin
• waveguide on the crystal
• These can guide light and provide opportunities
  for optical signal
• processing

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MACQUARIE UNIVERSITY, DEPARTMENT OF
PHYSICS RESEARCH Opals

• Opals are examples of 3D photonic crystals which
  can control the propagation
• of light in every direction
• We are combining opals with optical fibres and
  with waveguides to create new
• types of photonic devices to control and guide
  light

A/Prof Judith Dawes,Judith_at_ics.mq.edu.au, Tel
02 9850 8903ARC Centre of Excellence
(CUDOS_at_MQ)Centre for Lasers and Applications,
Department of Physics