TY - JOUR
T1 - Fibre optic beam delivery system for high peak power laser PIV illumination
AU - Hand, Duncan Paul
AU - Entwistle, Jonathan D.
AU - Maier, Robert Raimund Josef
AU - Kuhn, Andreas
AU - Greated, Clive A.
AU - Jones, Julian David Clayton
PY - 1999/3
Y1 - 1999/3
N2 - Diffractive optical elements (DOEs) are used to couple Q-switched and frequency-doubled Nd:YAG laser beams into optical fibres to achieve significantly increased damage thresholds, enabling fibre optic beam delivery for high-speed particle image velocimetry (PIV) measurements. For single fibre delivery systems, the maximum pulse energy density that can be transmitted is increased by a factor of 5-10 compared with the best that can be achieved using conventional optics, of up to 10 mJ in a 200 µm core diameter fibre at 532 nm. We also applied the DOE arrangement to our previously developed bundle delivery system, comprising nineteen 200 µm core diameter fibres. On testing, over 1000 pulses with energies of 30 mJ were successfully transmitted, with no indication of damage. This allows fibre delivery to become a practical option for many air-flow PIV applications, as demonstrated here with measurements of flow in a square duct.
AB - Diffractive optical elements (DOEs) are used to couple Q-switched and frequency-doubled Nd:YAG laser beams into optical fibres to achieve significantly increased damage thresholds, enabling fibre optic beam delivery for high-speed particle image velocimetry (PIV) measurements. For single fibre delivery systems, the maximum pulse energy density that can be transmitted is increased by a factor of 5-10 compared with the best that can be achieved using conventional optics, of up to 10 mJ in a 200 µm core diameter fibre at 532 nm. We also applied the DOE arrangement to our previously developed bundle delivery system, comprising nineteen 200 µm core diameter fibres. On testing, over 1000 pulses with energies of 30 mJ were successfully transmitted, with no indication of damage. This allows fibre delivery to become a practical option for many air-flow PIV applications, as demonstrated here with measurements of flow in a square duct.
KW - Fibre optic beam delivery
KW - Fluid flow analysis
KW - Fluid flow velocity
KW - Pulsed laser illumination
UR - http://www.scopus.com/inward/record.url?scp=0033100768&partnerID=8YFLogxK
U2 - 10.1088/0957-0233/10/3/021
DO - 10.1088/0957-0233/10/3/021
M3 - Article
SN - 0957-0233
VL - 10
SP - 239
EP - 245
JO - Measurement Science and Technology
JF - Measurement Science and Technology
IS - 3
ER -