Is it Cold Enough, Yet?

Mayerhofer, R.; May, Andrew B.; Serbin, Jürgen

doi:10.1002/latj.201600008

Cited by 2 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the tissue ablation with ns laser sources depends on the linear absorption properties of the tissue and therefore on the color of the eye (1)(2)(3)(4)(5)(6)(7). However, such unintended results can be counteracted by using ultrashort pulses (USP) (8)(9)(10)(11)(12)(13). The main advantage of these pulseswhich have a pulse width of a few picoseconds or less-is to be near the regime of cold material ablation.…”

Section: Open Access Edited Bymentioning

confidence: 99%

Ophthalmic surgeries on post mortem porcine eyes with picosecond ultrashort laser pulses

Körber,

Fellinger,

Fritsche

et al. 2024

Front. Med.

View full text Add to dashboard Cite

PurposeThis work demonstrates significant advantages in ophthalmic surgeries through the use of picosecond ultrashort laser pulses instead of state-of-the-art nanosecond laser pulses. These ultrashort lasers shall serve as universal tools more effectively combining advantages of high precision, low impact and economic advantages compared to existing instruments.MethodsAs samples, we used post-mortem porcine eyes on which we performed the experiments with both picosecond and nanosecond lasers. Performed surgeries were laser iridotomy, (post-) cataract treatment/capsulotomy and selective laser-trabeculoplasty. Pulse widths were between 12 ps and 220 ns with pulse energies between 30 μJ and 10 mJ at 532 nm and 1,064 nm. Additionally, we investigated accompanying shock waves, cavitation bubbles, and heat effects during the ablation processes.ResultsFor all surgeries, significant differences were observed between picosecond and nanosecond pulses: It was possible to scale the pulse energy down to 10 of microjoules rather than requiring millijoules, and resulting tissue ablations are much more precise, more deterministic and less frayed. The shock wave and cavitation bubble investigation revealed major differences in pressure between picosecond pulses (0.25 MPa, 50 μJ) and nanosecond pulses (37 MPa, 5 mJ). The heat input during ablation could be lowered by two orders of magnitude.ConclusionPicosecond ultrashort laser pulses show substantial benefits for several ophthalmic surgeries, with regard to ablation precision, shock wave generation and heat input. They are better than state-of-the-art ophthalmic nanosecond lasers in all aspects tested.

show abstract

Section: Open Access Edited Bymentioning

confidence: 99%

Ophthalmic surgeries on post mortem porcine eyes with picosecond ultrashort laser pulses

Körber,

Fellinger,

Fritsche

et al. 2024

Front. Med.

View full text Add to dashboard Cite

show abstract

Femtosecond Pulsed Ti:Sapphire Laser-Assisted Surface Texturing on Piston Ring and Its Tribology Characterization

Ezhilmaran¹,

Vasa

Krishnan

et al. 2020

Journal of Tribology

View full text Add to dashboard Cite

Femtosecond laser-assisted surface texturing of compression piston-rings is proposed and demonstrated. A femtosecond pulsed Ti3+:sapphire laser is used to generate dimples of the same size but with different area density on a moly-chrome ceramic deposited cast iron piston ring. The influence of the surface morphology and tribology operating conditions, such as reciprocating frequency and temperature of the lubricant, on friction and wear characteristics of textured piston rings and plateau honed liner samples is investigated. A decrease in the friction coefficient is observed with the texturing of rings. The dimple area density, which is defined as the ratio of the total textured area and the total area of the surface, of 16% and 27% offered a reduced coefficient of friction and minimize wear on the liner surface.

show abstract

Is it Cold Enough, Yet?

Cited by 2 publications

References 2 publications

Ophthalmic surgeries on post mortem porcine eyes with picosecond ultrashort laser pulses

Ophthalmic surgeries on post mortem porcine eyes with picosecond ultrashort laser pulses

Femtosecond Pulsed Ti:Sapphire Laser-Assisted Surface Texturing on Piston Ring and Its Tribology Characterization

Contact Info

Product

Resources

About