Anti-Fungal Laser Treatment of Paper: A Model Study with a Laser Wavelength of 532 nm

Linear and Nonlinear Optical Properties of Natural Dyes Freestanding Films and Application in Optical Limiting

10.32792/utq/utjsci/vol7/2/30 ◽

2020 ◽

pp. 139-143

Keyword(s):

Absorption Coefficient ◽

Water Solution ◽

Optical Limiting ◽

Refraction Index ◽

Laser Wavelength ◽

Solid State Laser ◽

Natural Dyes ◽

Linear And Nonlinear ◽

532 Nm ◽

Absorbance Spectra

Natural dyes were followed and prepared from a pomegranate, purple carrot, and eggplant peel. The absorbance spectra was measured in the wavelength range 300-800 nm. The linear properties measurements of the prepared natural dye freestanding films were determined include absorption coefficient (α0), extinction coefficient (κ), and linear refraction index (n). The nonlinear refractive index n2 and nonlinear absorption coefficient β2 of the natural dyes in the water solution were measured by the optical z-scan technique under a pumped solid state laser at a laser wavelength of 532 nm. The results indicated that the pomegranate dye can be promising candidates for optical limiting applications with significantly low optical limiting of 3.5 mW.

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Spectrochemical Analysis of Liquids Using Laser-Induced Plasma Emissions: Effects of Laser Wavelength

Applied Spectroscopy ◽

10.1366/0003702971938812 ◽

1997 ◽

Vol 51 (1) ◽

pp. 87-91 ◽

Cited By ~ 70

Author(s):

W. F. Ho ◽

C. W. Ng ◽

N. H. Cheung

Keyword(s):

Laser Pulse ◽

Signal To Noise Ratio ◽

Laser Wavelength ◽

Spectrochemical Analysis ◽

Liquid Jets ◽

Single Shot ◽

Transient Nature ◽

Vapor Plume ◽

193 Nm ◽

532 Nm

The plasma plume emissions produced by pulsed (∼ 10 ns) laser ablation of liquid jets were monitored for spectrochemical analysis. Laser wavelengths at 532 and 193 nm were used, and sodium was the test analyte. As expected, the 532-nm laser pulse produced very intense plasma continuum emissions that masked the sodium signal for the first hundred nanoseconds, especially near the bright core of the vapor plume. Neither time-gating nor spatial masking could significantly improve the single-shot signal-to-noise ratio, since the transient nature of the emissions placed stringent demands on timing precision while the small size of the plume required accurate mask positioning—both antithetical to the inherent instability of jet ablation. In sharp contrast, the 193-nm laser pulse produced relatively dim plasma flash but intense sodium emissions, rendering it ideal for analytical applications.

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Efficacy of laser treatment of tattoos using lasers emitting wavelengths of 532 nm, 755 nm and 1064 nm

British Journal of Dermatology ◽

10.1111/j.1365-2133.2004.05658.x ◽

2004 ◽

Vol 150 (2) ◽

pp. 245-251 ◽

Cited By ~ 23

Author(s):

B.M. Prinz ◽

S.R. Vavricka ◽

P. Graf ◽

G. Burg ◽

R. Dummer

Keyword(s):

Laser Treatment ◽

532 Nm

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Long-pulsed 532-nm Nd:YAG laser treatment for small acquired melanocytic nevi in a single session: an 8-year study on 350 Yemeni patients

Journal of Cosmetic and Laser Therapy ◽

10.3109/14764172.2013.854631 ◽

2013 ◽

Vol 16 (1) ◽

pp. 14-20 ◽

Cited By ~ 8

Author(s):

Mohammad Ali Alshami

Keyword(s):

Laser Treatment ◽

Nd:Yag Laser ◽

Single Session ◽

Melanocytic Nevi ◽

532 Nm

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LASER TATTOO REMOVAL COMPARISON BETWEEN 1064 AND 532 NM OF A Q-SWITCHEd Nd:YAG LASER TREATMENT

Jurnal Teknologi ◽

10.11113/jt.v78.7499 ◽

2016 ◽

Vol 78 (3) ◽

Author(s):

Nada Abusalah Almabrouk Imrigha ◽

Lau Pik Suan ◽

Shumaila Islam ◽

Ganesan Krishnan ◽

Noriah Bidin

Keyword(s):

Skin Biopsy ◽

Laser Treatment ◽

Laser Fluence ◽

Pulse Energy ◽

Single Pulse ◽

Skin Damage ◽

Laser Method ◽

Yag Laser ◽

Tattoo Removal ◽

532 Nm

Invention of the Q-switch advanced laser method is the most effective methods of tattoo removal compared to other methods of i.e. chemical, mechanical and surgical. In this study, we are reporting black pigment tattoo removal by comparing two wavelengths 532 nm and 1064 nm of Q-switched Nd-YAG laser. Using a single-pulse laser at 1064 nm wavelength, the maximum laser fluence for skin damage is 3.04 J/cm2 with pulse energy 0.55 J. While, at 532 nm wavelength, maximum laser fluence is 0.5 J/cm2 with pulse energy 0.42 J at 8-10 ns for tattooed skins. Moreover, after 1064 nm and 532 nm laser irradiations, skin biopsy of black tattooed rat’s skin demonstrates the ink granules local redistribution. Microscopic study indicates that black ink particles become smaller and vanished from the skins after 1064 nm laser treatment. The findings of this study indicate that 1064 nm wavelengths of Q-switched Nd-YAG laser treatment with 0.55 J pulse energy, is one of the significant methods of black tattoo removal with remarkable differences.

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Q-Switched Laser Treatment for Freckles in Individuals with Skin Type V

Aesthetics in Dermatology and Surgery ◽

10.1159/000454913 ◽

2017 ◽

Vol 1 (1) ◽

pp. 2-7

Author(s):

Ganesh S. Pai ◽

Anusha H. Pai

Keyword(s):

Laser Treatment ◽

Laser Therapy ◽

Skin Type ◽

Color Test ◽

Satisfactory Response ◽

Exposed Skin ◽

Type V ◽

532 Nm

Freckles are usually thought of as small, poorly marginated, well-circumscribed, pale brown macules present on sun-exposed skin areas in fair-complexioned individuals. However, freckles also occur in patients who have skin types IV and V, and there is a risk of prolonged depigmentation after treatment with a Q-switched laser emitting wavelengths of 532 nm. Unlike in fair-complexioned patients with light eyes and auburn hair who respond well but relapse in a matter of weeks, patients with skin type V show a permanent and satisfactory response to laser therapy. However, lower energies have to be used to prevent permanent hypopigmentation, which stands out in patients with skin of color. It is advisable to perform test spots on freckles before treating the entire face. After treatment, freckles can become of an ash white color. Test spots can be evaluated after 6 weeks. Sunscreen should be mandatory after the procedure. Additionally, freckles should be differentiated from lentigines by Wood lamp examination, where the superficial freckles get accentuated. Lentigines are treated using wavelengths of 1,064 nm.

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The Feature of Laser Deposition of Polymeric Composite Films from an Active Gas Phase

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.480-481.30 ◽

2011 ◽

Vol 480-481 ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

Zhu Bo Liu ◽

Xiao Hong Jiang ◽

Bing Zhou ◽

M.A. Yarmolenko ◽

D.L. Gorbachev ◽

...

Keyword(s):

Laser Radiation ◽

Gas Phase ◽

Composite Films ◽

Polymeric Composite ◽

Laser Wavelength ◽

Attenuated Total Reflection ◽

Silicon Films ◽

Organic Silicon ◽

Order Degree ◽

532 Nm

The organic-silicon films, polytetrafluorethylene (PTFE) films and its composite films with copper have been fabricated from an active gas phase by pulse laser dispersion from initial powder species. The features of all films obtained were studied with the application of attenuated total reﬂection-Fourier transform infrared (ATR-FTIR) spectroscopy. Our results suggest that the wavelength of laser radiation impact a strong effect on the molecular structure of all films. Specifically, the peaks corresponding to the detachment of C-H bonds in the organic-silicon films and its Cu doped films at a laser wavelength of 532 nm and the destruction of the Si-O-Si groups at 266 nm due to the ultraviolet radiation have been observed. Interestingly, the concentration of Si-С6Н5 groups relative increases with a decremental of the wavelength of laser radiation. In addition, the PTFE films formed at a laser wavelength of 355 nm presented a lower order degree and high amorphous phase, while PTFE-Cu composite films at laser wavelength 266 nm exhibited enhanced crystallinity due to the presence of copper species, wherein being served as nucleation centers. Remarkably, the wavelengths of laser radiation nearly play no effect on the orderness of PTFE-Cu composite films.

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