The aim of this study was to evaluate the efficacy and safety of femtosecond laserassisted cataract surgery flacs versus conventional phacoemulsification cataract surgery cpcs in the treatment of cataract. Femtosecond laser and refractive surgery in the early. When used in conjunction with an additional standard femtosecond opa. Each technique provides distinct measuring resolutions and ambiguity ranges which are. Femtosecond lasers have been proven to be a powerful tool for advanced materials processing on both the micro and nanoscale. We present a simple method for fabricating superhydrophobic silicon surfaces.
Femtosecond laser micromachining photonic and microfluidic. Sprite xt is a flexible ultrafast, femtosecond laser source. Femtosecond laser fabrication has grown to be a major method of extreme manufacturing because of the extreme energy density and spatial and temporal scales of femtosecond lasers. The femtosecond laser has been utilized experimentally in preparation of donor tissue for endothelial keratoplasty as well as in vivorabbit models. At that time, the french ministry of education decided that, in view of the growing importance of ultrashort laser pulses for the national scienti. Femtosecond laser versus mechanical keratome flaps in wavefron guided laser assisted in situ keratomileusis. Pdf femtosecond lasers for optical coherence tomography. Onestep fabrication of nanostructures by femtosecond laser. Rp photonics encyclopedia femtosecond lasers, ultrashort. As explained, the main mechanism behind the femtosecond laser surface. Sensors free fulltext femtosecond laser fabrication of.
Aug, 2015 the aim of this study was to evaluate the efficacy and safety of femtosecond laser assisted cataract surgery flacs versus conventional phacoemulsification cataract surgery cpcs in the treatment of cataract. Fabrication of micro fresnel zone plate lens on a mode. Threedimensional residuefree volume removal inside sapphire. For laser pulses 1ps, ablation will be dominated by thermal processes i. High incidence of rainbow glare after femtosecond laser. Femtosecond laser micromachining was first demonstrated in 1994, when a femtosecond laser was used to ablate micrometresized features on silica and silver surfaces 1,2. The physical effects and the mechanism of interaction between femtosecond lasers and materials are distinct from those in traditional processes. Pdf principles of physics of femtosecond laser researchgate. After ablation, the donor lenticule was peeled from the posterior surface and examined under light and scanning electron microscopy. Most femtosecond laser complications appear to be selflimiting, but one does require some treatment when it occurs. Femtosecond lasers are a type of laser that discharges optical pulses in femtoseconds.
Femtosecond laserassisted flap creation in lasik surgery has rapidly become popular with increasing safety and efficacy over time 1,2,3,4. The first clinical report of a human eye treated by femtosecond laser cataract surgery was in hungary in 2008 12. Thermal analysis of gold nanorods heated with femtosecond. Femtosecond laser micromachining can be used either to remove materials or to change a materials properties, and can be applied to both absorptive and.
A femtosecond laser is a laser which emits optical pulses with a duration well below 1 ps ultrashort pulses, i. A laser operated in this way is sometimes referred to as a femtosecond laser, for example in modern refractive surgery. Inactivation of viruses with a femtosecond laser via. Additionally, inspired by the underwater superaerophilicity of lotus leaves, we showed that the. Femtosecond laser micromachining in transparent materials. Typical microstructure formation after fs laser pulses. Femtosecond laser interaction on a silicon target torres, 2011. Alan solinsky, mddavid jeng, md10 farmington avewest hartford, ct 06107860 2332020david. It has a high average output power of 600 mw, while maintaining a laser in situ keratomileusis lasik. Photosensitivity of the erybcodoped schott iog1 phosphate glass using 248 nm, femtosecond, and picosecond laser radiation.
Femtosecond laser micromachining can be used either to remove materials or to change a materials properties, and can be applied to both absorptive and transparent substances. The excimer laser and femtosecond laser were connected and the data including refraction, keratometry readings, and flap parameters exchanged between the 2 machines. Femtosecond laser assisted flap creation in lasik surgery has rapidly become popular with increasing safety and efficacy over time 1,2,3,4. Durrie ds, kezirian gm 2005 femtosecond laser versus mechanical keratome flaps in wavefront guided laser in situ keratomileusis.
By varying the laser fluence, we can tune the surface. Bioinspired design of underwater superaerophobic and. Visumax femtosecond laser system carl zeiss meditec. We present a compact allfiber zone plate lens directly ablated on the surface of a modeexpanded hybrid fiber end by using a high precision femtosecond laser processing technique. Femtosecond laser flap parameters and visual outcomes in. In addition, the fsl allows better circularity of the anterior. Femtosecond lasers belong to a class of ultrashort pulse lasers or ultrafast lasers. To achieve a sufficiently large beam size and focusing efficiency, a segment of a coreless silica fiber having a 200mum diameter was adapted. Mode locking lasers are used to produce such ultrashort pulses. The color of voxels was bluish white because of plasma emission. To evaluate a new technique for penetrating keratoplasty pk with the use of a new software algorithm for a femtosecond laser that is designed to create penetrating cuts for pk in the treatment. We describe a combined interferometric scheme that enables absolute distance measurements using a femtosecond pulse laser. Driftfree femtosecond timing synchronization of remote. May 28, 20 femtosecond laser assistedcataractsurgery 1.
Femtosecond lasers for optical coherence tomography article pdf available in proceedings of spie the international society for optical engineering 79 december 2008 with 486 reads. The first analytical application was reported in 1996, using adenine as a sample. The basic concept was demonstrated using a nanosecond laser in kimura et al. They arise in the visible and infrared range from femtosecond lasers, and at shorter. Efficacy and safety of femtosecond laserassisted cataract. Silicon wafer substrates in the aqueous solution of silver nitrate were machined by the femtosecond laser direct writing to achieve simultaneously in onestep the generation of gratinglike nanostructures on the surface of the substrate and the formation of silver. The mechanism of femtosecond laser interaction with both metals and dielectric materials has been studied intensively in recent times 4, 1, 34. Several weeks after surgery, these patients develop an intense sensitivity to bright light. Mar 17, 2008 femtosecond lasers are a type of laser that discharges optical pulses in femtoseconds. Femtosecond lasers have revolutionized the processing of materials, since their ultrashort pulse width and extremely high peak intensity allows highquality micro and nanofabrication of threedimensional 3d structures. Several advantages of the femtosecond laser over mechanical microkeratomes have been reported in. Femtosecondscale synchronization using modelocked lasers has been limited to periods of just a few minutes. Femtosecondlaserassisted cataract surgery flacs springerlink. Any user of this site is welcome to upload data sheets for products they use and recommend.
Photosensitivity of the erybcodoped schott iog1 phosphate glass using 248. Now it is shown that, by combining a number of laser techniques, sub10fsprecision. Femtosecond laser micromachining of transparent material is a powerful and versatile technology. Unlike linear photon absorption that follows beerlambert law seen in nanosecond pulse regime, the absorption of laser energy with pulse duration in order of. After corneal pachymetry, the femtosecond laser was used to create a donor lenticule by using a variety of diameter ablations, 150. Yag laser and the femtosecond laser have a similar wavelength, respectively 1,064 nm and 1,0301,060 nm, but the femtosecond laser provokes less damage in terms. A roundup of recent papers in the field of photonics. Structural modification of amorphous fused silica under. Femtosecond laser which belong to the category of ultrafast lasers or ultrashort pulse lasers emit optical pulses with duration much below 1ps of the order of 1015 sec. Femtosecond laser cataract surgery eye and vision full text. Pdf femtosecond laser fsl is an infrared laser with a wavelength of 1053 nm. A micronanoscale hierarchical rough structure inspired by the underwater superaerophobicity of fish scales was fabricated by ablation of a silicon surface by a femtosecond laser.
As explained, the main mechanism behind the femtosecond laser surface modification is multiphoton phenomenon and nonthermal processes. When used in conjunction with an additional standard femtosecond opa, it offers the potential to provide both femtosecond and picosecond tunable beams simultaneously. Our experimental results show that for a visible femtosecond laser having. For laser pulses 2008 article id 868767 research article. Randomized controlled trials rcts were searched in pubmed, embase and the cochrane central register of controlled trials. Femtosecond laser fsl cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis. The method consists of irradiating silicon wafers with femtosecond laser pulses and then coating the surfaces with a layer of fluoroalkylsilane molecules. Femtosecond lasers belong to a class of ultrashort pulse lasers. The resultant silicon surface showed superhydrophilicity in air and became superaerophobic after immersion in water. Compared with traditional laser processing techniques that use longer pulse or continuous wave lasers, femtosecond laser micromachining offers several key advantages due to its unique characteristics of ultrashort pulse width and extremely high peak intensity. Flap creation is a critical step in laser in situ keratomileusis lasik. One of the ways we help our community of laser scientists and engineers find the best products for their projects is by hosting a free openindex product database. Spie 7005, highpower laser ablation vii, 70051t 14 may 2008. By increasing the etching temperature, complete volume etching without residue was achieved.
It thus also belongs to the category of ultrafast lasers or ultrashort pulse lasers which also include picosecond lasers. When using femtosecond laser for flap creation, each pulse of the laser causes the generation of a small amount of microplasma at its focal point in the corneal tissue leading to formation of microscopic gas bubbles and cavitations, which then dissipate. Efforts to improve the safety and predictability of the lamellar incision have fostered the development of femtosecond lasers. This unique capability opens up a new route for fabrication of microfluidic sensors for biochemical applications. The period of the breathing modes has been measured for different sizes of particles and the corresponding temperatures are calculated using the temperature dependent elastic constants of gold. The femtosecond fs laser operates in the infrared range wavelength. This paper reports an efficient fabrication of nanostructures on silicon substrates for surfaceenhanced raman scattering sers. The experimental results were supported by a thermodynamic. The inactivation of viruses such as m bateriophages subject to excitations by a very low power visible femtosecond laser has been studied. Femtosecond laser systems have strict ambient humidity and temperature requirements for proper operation, but advances in fs laser technology are making the newer machines less sensitive to environmental perturbations. This course provides an overview of howfemtosecond lasers can and will benefitpatients with cataracts and astigmatism. Femtosecond lasers in ophthalmology touchophthalmology. It enables subsequently less phacoemulsification energy and time to be employed, which has gains in terms of reduced corneal oedema.
Modelocking is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, on the order of picoseconds 10. This course provides an overview of howfemtosecond lasers can and. In this chapter, the focus will be on understanding the basics of femtosecond laser ablation processes which include laser energy transport, ablation mechanisms, ablation threshold, plume hydrodynamics and evolution. We applied the femtosecond laserassisted etching technique, that is, irradiation of focused femtosecond laser pulses followed by selective chemical etching, to volume removal inside sapphire. The first femtosecond laser designed for instrumentation and oem integration, 920 nm and 1064 nm axon lasers are priced at breakthrough cost to grow applications such as twophoton microscopy, harmonic generation microscopy, and inspection. One of 3 curved contact glass sizes for the femtosecond laser was selected depending on corneal diameter measured with an atlas topography system carl zeiss meditec ag.
Femtosecond lasers have shown promising applications in bio, energy, and aerospace sectors in recent years. Femtosecond lasers and laser assisted in situ keratomileusis. It is a maskless technology that allows rapid device prototyping, has intrinsic threedimensional capabilities and can produce both photonic and. Choose your output power up to multiwatts, pulse width femtosecond or picosecond models, wavelength range fixed wavelength or tunable, and pulse repetition. At room temperature, volume etching only slightly advanced while residue remained inside the volume. The nonlinear and nonequilibrium effects of the interaction have given. It delivers stability, reliability and productivity and is equally at home in the lab or as part of an oem application. Free post a pdf data sheet to our openindex product research engine.
Ultraviolet femtosecond laser ionization mass spectrometry. Femtosecond laserassisted endothelial keratoplasty. This method is combined with synthetic wavelength interferometry swi, time of flight tof and spectrallyresolved interferometry sri using the optical comb of femtosecond laser. Femtosecond laser in refractive and cataract surgeries. Cataract surgery femtosecond laser chirped pulse amplification optical. Femtosecond laser an overview sciencedirect topics. A laser operated in this way is sometimes referred to as a femtosecond laser, for. Fs lasers are also rapidly gaining popularity in many other fields of medicine, such as in dentistry and neurosurgery.
Metal colorization with femtosecond laser pulses 2008. Several advantages of the femtosecond laser over mechanical microkeratomes have been reported in lasik surgery. A compact synchrotron radiation source driven by a laser plasma wakefield accelerator. Femtosecond lasers versatile ultrafast ytterbium amplifier ideal for either timeresolved spectroscopy or material processing rapid fx rapid fx this industrial femtosecond laser system features 10 w average power at 100 khz and is ideal for high throughput micromachining. The ifs femtosecond laser is an ophthalmic surgical laser indicated for use in patients undergoing surgery or treatment requiring initial lamellar resection of the cornea, in treatment requiring initial lamellar resection of the cornea to create tunnels for placement of corneal ring segments, in treatment requiring arcuate cutsincisions in. Thus, a femtosecond laser pulse ends before the electrons thermally. Femtosecond scale synchronization using modelocked lasers has been limited to periods of just a few minutes. The lasermatter interaction and the mechanisms leading to ablation are dissimilar for different laser pulse widths. We applied the femtosecond laser assisted etching technique, that is, irradiation of focused femtosecond laser pulses followed by selective chemical etching, to volume removal inside sapphire. The laser irradiation creates a surface morphology that exhibits structure on the micro and nanoscale. Superhydrophobic surfaces prepared by microstructuring of.
820 943 613 1231 1353 1413 966 1447 157 768 954 487 842 1283 1059 909 727 617 945 387 362 1380 935 347 532 7 1283 9 1460 85 909 761 141 815 386 1302 1024 1444 1472 503 693 1037 688 1446 992 1042