Transient Dynamics Measurement of Light-material Interaction for Laser Optics

Laser damage performance is an important parameter to evaluate the quality of high power laser optical components. Understanding the physical mechanism of the interaction between laser and optical material is of great significance for improving the laser damage resistance of optical elements. For nanosecond pulsed laser, the time duration of laser-induced damage is ultra-short, and the measurement of related physical quantities is very difficult. Therefore, the Time Resolved Pump and Probe (TRPP) technique can effectively solve this problem. TRPP shadow imaging can obtain the transient dynamic information in range of picosecond to microsecond, including the plasma formation in the early stage, the shock wave propagation, the crack expanding, material ejection and other phenomena. Moreover, the ultra-fast physical quantities can be accurately measured by employing two detective beams with perpendicular polarization directions, for example S and P polarization light. All those information provides effective experimental data to reveal the physical mechanism of damage process.

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High laser induced damage threshold photoresists for nano-imprint and 3D multi-photon lithography

Nanophotonics ◽

10.1515/nanoph-2021-0263 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Elmina Kabouraki ◽

Vasileia Melissinaki ◽

Amit Yadav ◽

Andrius Melninkaitis ◽

Konstantina Tourlouki ◽

...

Keyword(s):

Nanoimprint Lithography ◽

Three Dimensional ◽

Damage Threshold ◽

Laser Pulses ◽

Intense Laser ◽

Optical Elements ◽

Photonic Circuits ◽

Future Production ◽

Intense Laser Pulses ◽

Laser Induced Damage

Abstract Optics manufacturing technology is predicted to play a major role in the future production of integrated photonic circuits. One of the major drawbacks in the realization of photonic circuits is the damage of optical materials by intense laser pulses. Here, we report on the preparation of a series of organic–inorganic hybrid photoresists that exhibit enhanced laser-induced damage threshold. These photoresists showed to be candidates for the fabrication of micro-optical elements (MOEs) using three-dimensional multiphoton lithography. Moreover, they demonstrate pattern ability by nanoimprint lithography, making them suitable for future mass production of MOEs.

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Performance of rapid-grown KDP crystals with continuous filtration

High Power Laser Science and Engineering ◽

10.1017/hpl.2015.7 ◽

2015 ◽

Vol 3 ◽

Cited By ~ 11

Author(s):

Guohang Hu ◽

Yueliang Wang ◽

Junxiu Chang ◽

Xiaoyi Xie ◽

Yuanan Zhao ◽

...

Keyword(s):

Near Infrared ◽

Laser Damage ◽

Damage Resistance ◽

Damage Initiation ◽

Micron Size ◽

Continuous Filtration ◽

Laser Induced Damage ◽

Almost All ◽

Lower Correlation ◽

Kdp Crystals

Rapid growth processing of KDP crystals was improved by employing continuous filtration to eliminate bulk defects. The performances of the KDP crystals, including scattering defects, laser damage resistance and transmittance, were measured and analyzed. Compared with rapid-grown KDP without continuous filtration, the transmittance in the near-infrared was increased by at least 2%, almost all of ‘micron size’ defects were eliminated and ‘sub-micron size’ defects were decreased by approximately 90%. Laser damage testing revealed that the laser-induced damage thresholds (LIDTs), as well as the consistency of the LIDTs from sample to sample, were improved greatly. Moreover, it identified that ‘micron size’ defects were the precursors which initiated laser damage at relative lower laser fluence (4–6 J cm−2), and there was a lower correlation between smaller size scattering defects and laser damage initiation. The improved consistency in the LIDTs, attributed to elimination of ‘micron size’ defects, and LIDT enhancement originated from the decreased absorption of the KDP crystals.

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Simulation of Large Scale KDP Crystal Polishing by Computer Controlled Micro-Nano Deliquescence

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.497.165 ◽

2012 ◽

Vol 497 ◽

pp. 165-169 ◽

Cited By ~ 3

Author(s):

He Ping Zhang ◽

Dong Ming Guo ◽

Xu Wang ◽

Hang Gao

Keyword(s):

Large Scale ◽

Surface Condition ◽

Single Point ◽

Damage Threshold ◽

Diamond Turning ◽

Water Soluble ◽

Optical Elements ◽

Kdp Crystal ◽

Computer Controlled ◽

Laser Induced Damage

Although Single Point Diamond Turning (SPDT) can do pretty well in optical surfacing of large scale KDP crystal, both the surface accuracy and integrity are considerably high; meanwhile as the defects of micro-waveness and stress are inevitable, the laser-induced damage threshold of KDP optical elements after SPDT still cannot be satisfied. Because of the characters of deliquescent and water-soluble, the process of computer controlled Micro-nano deliquescence is attempted to remove the residual micro-waveness on KDP surface after SPDT. Based on the assumption of Preston and the characters of Micro-nano deliquescence, the model of material removal ratio is suggested, the dwell time for ascertained KDP surface is solved, the processing of computer controlled Micro-nano deliquescence is simulated and the processed surface condition on theory is obtained. Besides, the influences of different parameters on the surfacing efficiency and accuracy are analyzed. Finally, three polishing tracks are comparatively analyzed. The simulation results are quite important in guiding the experimental polishing of large scale KDP by computer controlled Micro-nano deliquescence

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Early Dynamics of a Laser-induced Underwater Shock Wave

Journal of Fluids Engineering ◽

10.1115/1.4051385 ◽

2021 ◽

Author(s):

Guihua Lai ◽

Siyuan Geng ◽

Hanwen Zheng ◽

Zhifeng Yao ◽

Qiang Zhong ◽

...

Keyword(s):

Shock Wave ◽

Numerical Method ◽

Cavitation Bubble ◽

Laser Energy ◽

Optical Breakdown ◽

Pulsed Laser ◽

Underwater Shock Wave ◽

Time Resolved ◽

High Attenuation ◽

Nanosecond Pulsed Laser

Abstract The objective of this paper is to observe and investigate the early evolution of the shock wave, induced by a nanosecond pulsed laser in still water. A numerical method is performed to calculate the propagation of the shock wave within 1µs, after optical breakdown, based on the Gilmore model and the Kirkwood-Bethe hypothesis. The input parameters of the numerical method include the laser pulse duration, the size of the plasma and the maximally extended cavitation bubble, which are measured utilizing a high time-resolved shadowgraph system. The calculation results are verified by shock wave observation experiments at the cavitation bubble expansion stage. The relative errors of the radiuses and the velocity of the shock wave front, reach the maximum value of 45% at 5 ns after breakdown and decrease to less than 20% within 20 ns. The high attenuation characteristics of the shock wave after the optical breakdown, are predicted by the numerical method. The quick time and space evolution of the shock wave are carefully analyzed. The normalized shock wave width is found to be independent of the laser energy and duration, and the energy partitions ratio is around 2.0 using the nanosecond pulsed laser.

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Time resolved analysis of nanosecond pulsed laser processing of carbon fiber reinforced plastics

Journal of Laser Applications ◽

10.2351/1.4983242 ◽

2017 ◽

Vol 29 (2) ◽

pp. 022406 ◽

Cited By ~ 1

Author(s):

S. Bluemel ◽

J. Kuklik ◽

R. Staehr ◽

P. Jaeschke ◽

O. Suttmann ◽

...

Keyword(s):

Carbon Fiber ◽

Laser Processing ◽

Pulsed Laser ◽

Fiber Reinforced ◽

Time Resolved ◽

Carbon Fiber Reinforced Plastics ◽

Reinforced Plastics ◽

Nanosecond Pulsed Laser ◽

Pulsed Laser Processing ◽

Fiber Reinforced Plastics

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Laser-induced damage studies in optical elements using X-ray laser interferometric microscopy

10.1117/12.823302 ◽

2009 ◽

Author(s):

D. Margarone ◽

M. Kozlova ◽

J. Nejdl ◽

B. Rus ◽

T. Mocek ◽

...

Keyword(s):

Optical Elements ◽

X Ray ◽

Laser Induced Damage ◽

Laser Interferometric

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Numerical Study of Temperature and Incandescence Intensity of Nanosecond Pulsed-Laser Heated Soot Particles at High Pressures

Heat Transfer, Part A ◽

10.1115/imece2005-81322 ◽

2005 ◽

Cited By ~ 1

Author(s):

Fengshan Liu ◽

David R. Snelling ◽

Gregory J. Smallwood

Keyword(s):

Soot Particle ◽

High Pressures ◽

Particle Diameter ◽

Aggregate Size ◽

Primary Particle Diameter ◽

Time Resolved ◽

Soot Particles ◽

Nanosecond Pulsed Laser ◽

Primary Particles ◽

Laser Heated

Histories of temperature and incandescence intensity of nanosecond pulsed-laser heated soot particles of polydispersed primary particles and aggregate sizes were calculated using an aggregate-based heat transfer model at pressures from 1 atm up to 50 atm. The local gas temperature, distributions of soot primary particle diameter and aggregate size assumed in the calculations were similar to those found in an atmospheric laminar diffusion flame. Relatively low laser fluences were considered to keep the peak particle temperatures below about 3400 K to ensure negligible soot particle sublimation. The shielding effect on the heat conduction between aggregated soot particles and the surrounding gas was accounted for based on results of direct simulation Monte Carlo calculations. After the laser pulse, the temperature of soot particles with larger primary particles or larger aggregates cools down slower than those with smaller primary particles or smaller aggregates due to smaller surface area-to-volume ratios. The effective temperature of soot particles in the laser probe volume was calculated based on the ratio of thermal radiation intensities of the soot particle ensemble at 400 and 780 nm. Due to the reduced mean free path of molecules with increasing pressure, the heat conduction between soot particles and the surrounding gas shifts from the free-molecular to the transition regime. Consequently, the rate of conduction heat loss from the soot particles increases significantly with pressure. The lifetime of laser-induced incandescence (LII) signal is significantly reduced as the pressure increases. At high pressures, the time resolved soot particle temperature is very sensitive to both the primary particle diameter and the aggregate size distributions, implying the time-resolved LII particle sizing techniques developed at atmospheric pressure lose their effectiveness at high pressures.

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Dynamics of Ultrafast Laser Induced Damage in Single Crystal Ni-based Superalloy During Machining

MRS Proceedings ◽

10.1557/proc-980-0980-ii05-31 ◽

2006 ◽

Vol 980 ◽

Author(s):

Joel P. McDonald ◽

Shuwei Ma ◽

John A. Nees ◽

Tresa M. Pollock ◽

Steven M. Yalisove

Keyword(s):

Shock Wave ◽

Laser Fluence ◽

Ultrafast Laser ◽

Laser Exposure ◽

Mechanical Shock ◽

Incident Laser ◽

Machining Time ◽

Time Resolved ◽

Pump Probe ◽

Laser Induced Damage

AbstractPump-probe imaging of femtosecond pulsed laser ablation was performed to investigate the mechanical shock induced on an intermetallic superalloy CMSX-4 during femtosecond laser machining. Time resolved shadowgraphic images were collected of the shock wave produced in the air above the target following laser exposure (0-10.3 nanoseconds). The dimensions of the shock wave were measured as a function of delay time and laser fluence (1.27 J/cm2 - 62.8 J/cm2). Time-resolved shadowgraphic images of the ablation event will be presented, and the corresponding damage morphology as a function of incident laser fluence will be discussed.

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