Abstract

We report on the effects of various laser system parameters on the magnitude of phase change induced inside hydrogel-based contact lens materials in the two-photon absorption limit via a laser induced refractive index (LIRIC) technique. In comparison with near infrared writing at 1035 nm where four-photon absorption process dominates, blue writing at 405 nm allows for the achievement of a decent amount of phase change (one wave) with a low power and a fast scan speed due to a more efficient two photon absorption process. Efficacy of the LIRIC process could be further improved by taking advantage of intermediate repetition rate laser pulses instead of high repetition rate (> 60 MHz) pulses or low repetition rate (< 500 KHz) pulses. A generally applicable photochemical model based on multiphoton absorption mechanism and pulse overlapping effect in two dimensions is proposed to predict the scaling behavior of the induced phase change. A modified photochemical model incorporating a saturation factor is developed to account for the behavior at large phase shifts. The modified photochemical model also helps explain the inapparent dependence of the phase change on numerical aperture (NA) at low irradiation doses and the observed sub-linear inverse dependence on scan speed.

© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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Femtosecond laser micromachining in ophthalmic hydrogels: spectroscopic study of materials effects

Dan Yu, Ruiting Huang, and Wayne H. Knox
Opt. Mater. Express 9(8) 3292-3305 (2019)

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2019 (2)

2018 (3)

2017 (1)

2015 (2)

2014 (2)

K. Sugioka and Y. Cheng, “Ultrafast lasers – reliable tools for advanced materials processing,” Light: Sci. Appl. 3(4), e149 (2014).
[Crossref]

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

2013 (1)

J. Eichstädt, G. R. B. E. Römer, and A. J. Huis in’t Veld, “Determination of irradiation parameters for laser-induced periodic surface structures,” Appl. Surf. Sci. 264, 79–87 (2013).
[Crossref]

2011 (3)

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

L. Xu and W. H. Knox, “Lateral gradient index microlenses written in ophthalmic hydrogel polymers by femtosecond laser micromachining,” Opt. Mater. Express 1(8), 1416–1424 (2011).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

2009 (2)

2008 (4)

A. Baum, P. J. Scully, W. Perrie, D. Jones, R. Issac, and D. A. Jaroszynski, “Pulse-duration dependency of femtosecond laser refractive index modification in poly (methyl methacrylate),” Opt. Lett. 33(7), 651–653 (2008).
[Crossref]

L. Ding, D. Jani, J. Linhardt, J. F. Künzler, S. Pawar, G. Labenski, T. Smith, and W. H. Knox, “Large enhancement of femtosecond laser micromachining speed in dye-doped hydrogel polymers,” Opt. Express 16(26), 21914–21921 (2008).
[Crossref]

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

R. R. Gattas and E. Mazur, “Femtosecond laser micromachining in transparent materials,” Nat. Photonics 2(4), 219–225 (2008).
[Crossref]

2006 (1)

2005 (3)

S. M. Eaton, H. Zhang, P. R. Herman, F. Yoshino, L. Shah, J. Bovatsek, and A. Y. Arai, “Heat accumulation effects in femtosecond laser-written waveguides with variable repetition rate,” Opt. Express 13(12), 4708–4716 (2005).
[Crossref]

C. Wochnowski, M. A. Shams Eldin, and S. Metev, “UV-laser-assisted degradation of poly (methyl methacrylate),” Polym. Degrad. Stab. 89(2), 252–264 (2005).
[Crossref]

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

2004 (1)

2003 (2)

K. Kamada, K. Matsunaga, A. Yoshino, and K. Ohta, “Two photon-absorption-induced accumulated thermal effect on femtosecond Z-scan experiments studied with time-resolved thermal-lens spectrometry and its simulation,” J. Opt. Soc. Am. B 20(3), 529–537 (2003).
[Crossref]

P. J. Scully, D. Jones, and D. A. Jaroszynski, “Femtosecond laser irradiation of polymethylmethacrylate for refractive index gratings,” J. Opt. A: Pure Appl. Opt. 5(4), S92–S96 (2003).
[Crossref]

2001 (2)

2000 (1)

C. Wochnowski, S. Metev, and G. Sepold, “UV–laser-assisted modification of the optical properties of polymethylmethacrylate,” Appl. Surf. Sci. 154-155(1), 706–711 (2000).
[Crossref]

1998 (1)

K. Hirao and K. Miura, “Writing waveguides and gratings in silica and related materials by a femtosecond laser,” J. Non-Cryst. Solids 239(1-3), 91–95 (1998).
[Crossref]

1996 (2)

1982 (2)

N. D. Arora, J. R. Hauser, and D. J. Roulston, “Electron and hole mobilities in silicon as a function of concentration and temperature,” IEEE Trans. Electron Devices 29(2), 292–295 (1982).
[Crossref]

M. Takeda, H. Ina, and S. Kobayashi, “Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry,” J. Opt. Soc. Am. 72(1), 156–160 (1982).
[Crossref]

1967 (1)

Anderson, N.

Arai, A. Y.

Arora, N. D.

N. D. Arora, J. R. Hauser, and D. J. Roulston, “Electron and hole mobilities in silicon as a function of concentration and temperature,” IEEE Trans. Electron Devices 29(2), 292–295 (1982).
[Crossref]

Bauer, F.

Baum, A.

Blackwell, R.

Blackwell, R. I.

Bovatsek, J.

Boyd, R. W.

R. W. Boyd, Nonlinear Optics (Elsevier, 2008), Chap. 1 and Chap. 12.

Brisset, F.

Brooks, D. R.

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

Callan, J. P.

Cancado, L. G.

Cao, J.

Cerullo, G.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

R. Osellame, G. Cerullo, and R. Ramponi, Femtosecond Laser Micromachining (Springer, 2012).

Chan, J. W.

Cheng, Y.

K. Sugioka and Y. Cheng, “Ultrafast lasers – reliable tools for advanced materials processing,” Light: Sci. Appl. 3(4), e149 (2014).
[Crossref]

Chichkov, B. N.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Davis, K. M.

DeMagistris, M.

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

Ding, L.

Dudic, M.

Eaton, S. M.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

S. M. Eaton, H. Zhang, P. R. Herman, F. Yoshino, L. Shah, J. Bovatsek, and A. Y. Arai, “Heat accumulation effects in femtosecond laser-written waveguides with variable repetition rate,” Opt. Express 13(12), 4708–4716 (2005).
[Crossref]

Eichstädt, J.

J. Eichstädt, G. R. B. E. Römer, and A. J. Huis in’t Veld, “Determination of irradiation parameters for laser-induced periodic surface structures,” Appl. Surf. Sci. 264, 79–87 (2013).
[Crossref]

Ellis, J. D.

G. A. Gandara-Montano, A. Ivansky, D. E. Savage, J. D. Ellis, and W. H. Knox, “Femtosecond laser writing of freeform gradient index microlenses in hydrogel-based contact lenses,” Opt. Mater. Express 5(10), 2257–2271 (2015).
[Crossref]

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

Finlay, R. J.

Gandara-Montano, G. A.

Gattas, R. R.

R. R. Gattas and E. Mazur, “Femtosecond laser micromachining in transparent materials,” Nat. Photonics 2(4), 219–225 (2008).
[Crossref]

Ghiglia, D. C.

D. C. Ghiglia and M. D. Pritt, Two-Dimensional Phase Unwrapping: Theory, Algorithms, and Software (Wiley,1998).

Glezer, E. N.

Haškovcová, K.

Hauser, J. R.

N. D. Arora, J. R. Hauser, and D. J. Roulston, “Electron and hole mobilities in silicon as a function of concentration and temperature,” IEEE Trans. Electron Devices 29(2), 292–295 (1982).
[Crossref]

Hecht, E.

E. Hecht, Optics (Pearson Education, 2002), Chap. 4.

Her, T. H.

Hercher, M.

Herman, P. R.

Hirao, K.

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

K. Hirao and K. Miura, “Writing waveguides and gratings in silica and related materials by a femtosecond laser,” J. Non-Cryst. Solids 239(1-3), 91–95 (1998).
[Crossref]

K. M. Davis, K. Miura, N. Sugimoto, and K. Hirao, “Writing waveguides in glass with a femtosecond laser,” Opt. Lett. 21(21), 1729–1731 (1996).
[Crossref]

Hô, N.

Huang, L.

Huang, R.

Huis in’t Veld, A. J.

J. Eichstädt, G. R. B. E. Römer, and A. J. Huis in’t Veld, “Determination of irradiation parameters for laser-induced periodic surface structures,” Appl. Surf. Sci. 264, 79–87 (2013).
[Crossref]

Huser, T.

Hüttman, G.

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

Huxlin, K. R.

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

Ina, H.

Issac, R.

Ivansky, A.

Jani, D.

Jaroszynski, D. A.

A. Baum, P. J. Scully, W. Perrie, D. Jones, R. Issac, and D. A. Jaroszynski, “Pulse-duration dependency of femtosecond laser refractive index modification in poly (methyl methacrylate),” Opt. Lett. 33(7), 651–653 (2008).
[Crossref]

P. J. Scully, D. Jones, and D. A. Jaroszynski, “Femtosecond laser irradiation of polymethylmethacrylate for refractive index gratings,” J. Opt. A: Pure Appl. Opt. 5(4), S92–S96 (2003).
[Crossref]

Jones, D.

A. Baum, P. J. Scully, W. Perrie, D. Jones, R. Issac, and D. A. Jaroszynski, “Pulse-duration dependency of femtosecond laser refractive index modification in poly (methyl methacrylate),” Opt. Lett. 33(7), 651–653 (2008).
[Crossref]

P. J. Scully, D. Jones, and D. A. Jaroszynski, “Femtosecond laser irradiation of polymethylmethacrylate for refractive index gratings,” J. Opt. A: Pure Appl. Opt. 5(4), S92–S96 (2003).
[Crossref]

Juodkazis, S.

Kamada, K.

Kiedrowski, T.

Kiyan, R.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Knox, W. H.

D. Yu, R. Huang, and W. H. Knox, “Femtosecond laser micromachining in ophthalmic hydrogels: spectroscopic study of materials effects,” Opt. Mater. Express 9(8), 3292–3305 (2019).
[Crossref]

R. Huang and W. H. Knox, “Quantitative photochemical scaling model for femtosecond laser micromachining of ophthalmic hydrogel polymers: effect of repetition rate and laser power in the four photon absorption limit,” Opt. Mater. Express 9(3), 1049–1061 (2019).
[Crossref]

W. H. Knox, “Nonlinear Optics: Femtosecond lasers and nonlinear optics: New approaches solve old problems in ophthalmology,” Laser Focus World 54(3), 22–25 (2018).

G. A. Gandara-Montano, L. Zheleznyak, and W. H. Knox, “Optical quality of hydrogel ophthalmic devices created with femtosecond laser induced refractive index modification,” Opt. Mater. Express 8(2), 295–313 (2018).
[Crossref]

G. A. Gandara-Montano, V. Stoy, M. Dudič, V. Petrák, K. Haškovcová, and W. H. Knox, “Large optical phase shifts in hydrogels written with femtosecond laser pulses: elucidating the role of localized water concentration changes,” Opt. Mater. Express 7(9), 3162–3180 (2017).
[Crossref]

G. A. Gandara-Montano, A. Ivansky, D. E. Savage, J. D. Ellis, and W. H. Knox, “Femtosecond laser writing of freeform gradient index microlenses in hydrogel-based contact lenses,” Opt. Mater. Express 5(10), 2257–2271 (2015).
[Crossref]

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

L. Xu and W. H. Knox, “Lateral gradient index microlenses written in ophthalmic hydrogel polymers by femtosecond laser micromachining,” Opt. Mater. Express 1(8), 1416–1424 (2011).
[Crossref]

L. Ding, D. Jani, J. Linhardt, J. F. Künzler, S. Pawar, G. Labenski, T. Smith, and W. H. Knox, “Optimization of femtosecond laser micromachining in hydrogel polymers,” J. Opt. Soc. Am. B 26(9), 1679–1687 (2009).
[Crossref]

L. Ding, L. G. Cancado, L. Novotny, W. H. Knox, N. Anderson, D. Jani, J. Linhardt, R. I. Blackwell, and J. F. Künzler, “Micro-Raman spectroscopy of refractive index microstructures in silicone-based hydrogel polymers created by high-repetition-rate femtosecond laser micromachining,” J. Opt. Soc. Am. B 26(4), 595–602 (2009).
[Crossref]

L. Ding, D. Jani, J. Linhardt, J. F. Künzler, S. Pawar, G. Labenski, T. Smith, and W. H. Knox, “Large enhancement of femtosecond laser micromachining speed in dye-doped hydrogel polymers,” Opt. Express 16(26), 21914–21921 (2008).
[Crossref]

L. Ding, R. Blackwell, J. F. Künzler, and W. H. Knox, “Large refractive index change in silicone-based and non-silicone-based hydrogel polymers induced by femtosecond laser micro-machining,” Opt. Express 14(24), 11901–11909 (2006).
[Crossref]

R. Huang and W. H. Knox, “Femtosecond Micromachining of Ophthalmic Hydrogels: effects of laser repetition rate on the induced phase change in the two photon and four photon absorption limit,” in Conference on Lasers and Electro-Optics, OSA Technical Digest (Optical Society of America, 2019), paper AW4I.5.

Kobayashi, S.

Krol, D. M.

Kumar, A.

A. Kumar, Introduction to Solid State Physics (PHI Learning Private Limited, 2010), Chap. 9.

Künzler, J. F.

Kuznetsov, A.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Labenski, G.

Lancry, M.

Levi, M.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Linhardt, J.

Lopez, C.

MacRae, S.

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

Marcinkevicius, A.

Matsunaga, K.

Matsuo, S.

Mazur, E.

Metev, S.

C. Wochnowski, M. A. Shams Eldin, and S. Metev, “UV-laser-assisted degradation of poly (methyl methacrylate),” Polym. Degrad. Stab. 89(2), 252–264 (2005).
[Crossref]

C. Wochnowski, S. Metev, and G. Sepold, “UV–laser-assisted modification of the optical properties of polymethylmethacrylate,” Appl. Surf. Sci. 154-155(1), 706–711 (2000).
[Crossref]

Michalowski, A.

Milosavljevic, M.

Misawa, H.

Miura, K.

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

K. Hirao and K. Miura, “Writing waveguides and gratings in silica and related materials by a femtosecond laser,” J. Non-Cryst. Solids 239(1-3), 91–95 (1998).
[Crossref]

K. M. Davis, K. Miura, N. Sugimoto, and K. Hirao, “Writing waveguides in glass with a femtosecond laser,” Opt. Lett. 21(21), 1729–1731 (1996).
[Crossref]

Miwa, M.

Nishii, J.

Noack, J.

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

Nolte, S.

Novotny, L.

Ohta, K.

Osellame, R.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

R. Osellame, G. Cerullo, and R. Ramponi, Femtosecond Laser Micromachining (Springer, 2012).

Paltauf, G.

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

Pawar, S.

Perrie, W.

Petrák, V.

Poumellec, B.

Pritt, M. D.

D. C. Ghiglia and M. D. Pritt, Two-Dimensional Phase Unwrapping: Theory, Algorithms, and Software (Wiley,1998).

Ramponi, R.

R. Osellame, G. Cerullo, and R. Ramponi, Femtosecond Laser Micromachining (Springer, 2012).

Richardson, K.

Richardson, M.

Risbud, S.

Rivero, C.

Römer, G. R. B. E.

J. Eichstädt, G. R. B. E. Römer, and A. J. Huis in’t Veld, “Determination of irradiation parameters for laser-induced periodic surface structures,” Appl. Surf. Sci. 264, 79–87 (2013).
[Crossref]

Roulston, D. J.

N. D. Arora, J. R. Hauser, and D. J. Roulston, “Electron and hole mobilities in silicon as a function of concentration and temperature,” IEEE Trans. Electron Devices 29(2), 292–295 (1982).
[Crossref]

Sakakura, M.

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

Savage, D. E.

G. A. Gandara-Montano, A. Ivansky, D. E. Savage, J. D. Ellis, and W. H. Knox, “Femtosecond laser writing of freeform gradient index microlenses in hydrogel-based contact lenses,” Opt. Mater. Express 5(10), 2257–2271 (2015).
[Crossref]

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

Schulte, A.

Scully, P. J.

A. Baum, P. J. Scully, W. Perrie, D. Jones, R. Issac, and D. A. Jaroszynski, “Pulse-duration dependency of femtosecond laser refractive index modification in poly (methyl methacrylate),” Opt. Lett. 33(7), 651–653 (2008).
[Crossref]

P. J. Scully, D. Jones, and D. A. Jaroszynski, “Femtosecond laser irradiation of polymethylmethacrylate for refractive index gratings,” J. Opt. A: Pure Appl. Opt. 5(4), S92–S96 (2003).
[Crossref]

Sepold, G.

C. Wochnowski, S. Metev, and G. Sepold, “UV–laser-assisted modification of the optical properties of polymethylmethacrylate,” Appl. Surf. Sci. 154-155(1), 706–711 (2000).
[Crossref]

Shah, L.

Shams Eldin, M. A.

C. Wochnowski, M. A. Shams Eldin, and S. Metev, “UV-laser-assisted degradation of poly (methyl methacrylate),” Polym. Degrad. Stab. 89(2), 252–264 (2005).
[Crossref]

Shimizu, M.

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

Shimotsuma, Y.

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

Siegman, A. E.

A. E. Siegman, Lasers (University Science Books, 1986), Chap. 17.

Smith, T.

Stoy, V.

Sugimoto, N.

Sugioka, K.

K. Sugioka and Y. Cheng, “Ultrafast lasers – reliable tools for advanced materials processing,” Light: Sci. Appl. 3(4), e149 (2014).
[Crossref]

Suriano, R.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Takeda, M.

Turri, S.

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

Vallée, R.

Vogel, A.

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

Wang, N.

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

Watanabe, M.

Wochnowski, C.

C. Wochnowski, M. A. Shams Eldin, and S. Metev, “UV-laser-assisted degradation of poly (methyl methacrylate),” Polym. Degrad. Stab. 89(2), 252–264 (2005).
[Crossref]

C. Wochnowski, S. Metev, and G. Sepold, “UV–laser-assisted modification of the optical properties of polymethylmethacrylate,” Appl. Surf. Sci. 154-155(1), 706–711 (2000).
[Crossref]

Xu, L.

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

L. Xu and W. H. Knox, “Lateral gradient index microlenses written in ophthalmic hydrogel polymers by femtosecond laser micromachining,” Opt. Mater. Express 1(8), 1416–1424 (2011).
[Crossref]

Yoshino, A.

Yoshino, F.

Yu, D.

Zhang, H.

Zheleznyak, L.

Zoubir, A.

Appl. Opt. (1)

Appl. Phys. B: Lasers Opt. (1)

A. Vogel, J. Noack, G. Hüttman, and G. Paltauf, “Mechanisms of femtosecond laser nanosurgery of cells and tissues,” Appl. Phys. B: Lasers Opt. 81(8), 1015–1047 (2005).
[Crossref]

Appl. Phys. Lett. (1)

M. Sakakura, M. Shimizu, Y. Shimotsuma, K. Miura, and K. Hirao, “Temperature distribution and modification mechanism inside glass with heat accumulation during 250kHz irradiation of femtosecond laser pulses,” Appl. Phys. Lett. 93(23), 231112 (2008).
[Crossref]

Appl. Surf. Sci. (3)

C. Wochnowski, S. Metev, and G. Sepold, “UV–laser-assisted modification of the optical properties of polymethylmethacrylate,” Appl. Surf. Sci. 154-155(1), 706–711 (2000).
[Crossref]

R. Suriano, A. Kuznetsov, S. M. Eaton, R. Kiyan, G. Cerullo, R. Osellame, B. N. Chichkov, M. Levi, and S. Turri, “Femtosecond laser ablation of polymeric substrates for the fabrication of microfluidic channels,” Appl. Surf. Sci. 257(14), 6243–6250 (2011).
[Crossref]

J. Eichstädt, G. R. B. E. Römer, and A. J. Huis in’t Veld, “Determination of irradiation parameters for laser-induced periodic surface structures,” Appl. Surf. Sci. 264, 79–87 (2013).
[Crossref]

IEEE Trans. Electron Devices (1)

N. D. Arora, J. R. Hauser, and D. J. Roulston, “Electron and hole mobilities in silicon as a function of concentration and temperature,” IEEE Trans. Electron Devices 29(2), 292–295 (1982).
[Crossref]

Invest. Ophthalmol. Visual Sci. (2)

D. E. Savage, D. R. Brooks, M. DeMagistris, L. Xu, S. MacRae, J. D. Ellis, W. H. Knox, and K. R. Huxlin, “First Demonstration of Ocular Refractive Change Using Blue-IRIS in Live Cats,” Invest. Ophthalmol. Visual Sci. 55(7), 4603–4612 (2014).
[Crossref]

L. Xu, W. H. Knox, M. DeMagistris, N. Wang, and K. R. Huxlin, “Noninvasive Intratissue Refractive Index Shaping (IRIS) of the Cornea with Blue Femtosecond Laser Light,” Invest. Ophthalmol. Visual Sci. 52(11), 8148–8155 (2011).
[Crossref]

J. Non-Cryst. Solids (1)

K. Hirao and K. Miura, “Writing waveguides and gratings in silica and related materials by a femtosecond laser,” J. Non-Cryst. Solids 239(1-3), 91–95 (1998).
[Crossref]

J. Opt. A: Pure Appl. Opt. (1)

P. J. Scully, D. Jones, and D. A. Jaroszynski, “Femtosecond laser irradiation of polymethylmethacrylate for refractive index gratings,” J. Opt. A: Pure Appl. Opt. 5(4), S92–S96 (2003).
[Crossref]

J. Opt. Soc. Am. (1)

J. Opt. Soc. Am. B (3)

Laser Focus World (1)

W. H. Knox, “Nonlinear Optics: Femtosecond lasers and nonlinear optics: New approaches solve old problems in ophthalmology,” Laser Focus World 54(3), 22–25 (2018).

Light: Sci. Appl. (1)

K. Sugioka and Y. Cheng, “Ultrafast lasers – reliable tools for advanced materials processing,” Light: Sci. Appl. 3(4), e149 (2014).
[Crossref]

Nat. Photonics (1)

R. R. Gattas and E. Mazur, “Femtosecond laser micromachining in transparent materials,” Nat. Photonics 2(4), 219–225 (2008).
[Crossref]

Opt. Express (5)

Opt. Lett. (6)

Opt. Mater. Express (6)

Polym. Degrad. Stab. (1)

C. Wochnowski, M. A. Shams Eldin, and S. Metev, “UV-laser-assisted degradation of poly (methyl methacrylate),” Polym. Degrad. Stab. 89(2), 252–264 (2005).
[Crossref]

Other (9)

R. Huang and W. H. Knox, “Femtosecond Micromachining of Ophthalmic Hydrogels: effects of laser repetition rate on the induced phase change in the two photon and four photon absorption limit,” in Conference on Lasers and Electro-Optics, OSA Technical Digest (Optical Society of America, 2019), paper AW4I.5.

A. Kumar, Introduction to Solid State Physics (PHI Learning Private Limited, 2010), Chap. 9.

A. E. Siegman, Lasers (University Science Books, 1986), Chap. 17.

R. W. Boyd, Nonlinear Optics (Elsevier, 2008), Chap. 1 and Chap. 12.

Johnson and Johnson Vision Care, Inc., https://www.acuvue.com/sites/acuvue_us/files/d-08-14-04_1davdwl_pi-fig_0.pdf .

Pubchem, open chemistry database, https://pubchem.ncbi.nlm.nih.gov/substance/135213571#section=Top .

D. C. Ghiglia and M. D. Pritt, Two-Dimensional Phase Unwrapping: Theory, Algorithms, and Software (Wiley,1998).

E. Hecht, Optics (Pearson Education, 2002), Chap. 4.

R. Osellame, G. Cerullo, and R. Ramponi, Femtosecond Laser Micromachining (Springer, 2012).

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Figures (11)

Fig. 1.
Fig. 1. A sketch illustrates the overwriting factors in both horizontal and vertical dimensions.
Fig. 2.
Fig. 2. (a) Experimental configuration of the blue femtosecond laser writing system. HWP, half-wave plate; PBS, polarizing beam splitter; GTI mirrors, Gires-Tournois Interferometer mirrors. (b) Transmission spectra of Contaflex samples and J + J contact lenses along with femtosecond laser wavelengths used in the blue writing and NIR writing processes.
Fig. 3.
Fig. 3. DIC images showing 8 sets of phase bars written in Contaflex samples at powers from 40 mW to 75 mW. Smooth and uniform phase bars can be seen at a power below 60 mW while optical damage occurs at higher irradiation doses.
Fig. 4.
Fig. 4. Interferogram and phase map showing one wave of phase change induced by the phase bars inside Contaflex samples written at 55 mW, 200 mm/s, NA 0.45 and 8.3 MHz.
Fig. 5.
Fig. 5. Plots of the induced phase change as a function of average power (a, b) and as a function of single pulse energy (c, d) below the damage threshold at three different repetition rates. The experimental data at 1 MHz, 5 MHz and 8.3 MHz are fitted by power functions to illustrate the power dependence and the effect of repetition rate at NA 0.45.
Fig. 6.
Fig. 6. Below optical damage threshold, quantitative results showing the power dependency of phase change induced at NA 0.25 for Contaflex samples (a) and J + J contact lenses (b) via the fitting of power functions.
Fig. 7.
Fig. 7. DIC images showing cross sections of phase bars written inside Contaflex samples at different powers with NA 0.45 (a, b) and NA 0.25 (c, d). The length of the interaction region at 40 mW is estimated to be ∼20 µm at NA 0.45 and ∼40 µm at NA 0.25. Interaction volume generated at high NA is more confined and localized than low NA.
Fig. 8.
Fig. 8. Power function fitting for quantitative data obtained at NA 0.45 from Contaflex samples (a) and from J + J contact lenses (b).
Fig. 9.
Fig. 9. (a) DIC image of grating lines written at scan speeds of 5 mm/s, 50 mm/s, 100 mm/s and 150 mm/s. (b) DIC image of grating lines written by a rotational stage at scan speeds of 500 mm/s, 1.34 m/s and 2 m/s. (c) DIC image of grating lines written at 2.68 m/s, 3.35 m/s and 5 m/s. (d) DIC image of grating lines written at 5 m/s, 6.7 m/s and 8.37 m/s. (e) DIC image of grating lines written at 11.72 m/s on a smaller scale.
Fig. 10.
Fig. 10. Phase changes induced at different conditions are fitted by the photochemical model. Quantitative data were collected from Contaflex samples at NA 0.45 (a); from J + J contact lenses at NA 0.45 (b); from Contaflex samples at NA 0.25 (c); from J + J contact lenses at NA 0.25 (d).
Fig. 11.
Fig. 11. The modified photochemical model incorporating a saturation factor is used to fit qualitative data obtained from Contaflex samples and J + J contact lenses under different exposure conditions.

Tables (2)

Tables Icon

Table 1. Material constants γ2 of two materials at two NAs determined numerically by fitting the experimental data at 5 MHz with the photochemical model

Tables Icon

Table 2. Material constants γ2 and saturation phase changes ϕS determined by fitting the experimental results at 8.3 MHz with the modified photochemical model

Equations (12)

Equations on this page are rendered with MathJax. Learn more.

Δ ϕ = Δ n d λ
ω = λ π N A m
N = 2 ω υ S 2 ω t
D := ε E V O L ( β I m 1 L )
E = P a v g / υ
I = P a v g υ τ π ω 2
L = 2 π λ ω 2
V O L = 4 3 π ω 2 L
Δ ϕ = γ P a v g m N A 2 ( m 2 ) m m 2 υ m 1 τ m 1 λ 2 ( m 1 ) S t
Δ ϕ = γ 2 P a v g 2 υ τ λ 2 S t
Δ ϕ = ϕ 0 1 + D t o t D t o t , s a t
Δ ϕ = ϕ 0 1 + ϕ 0 ϕ s

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