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Fulltext Manipulating microbending losses in single mode optical fiber for pressure sensing

Wan Maisarah Mukhtar, Nur Auni Marzuki, Affa Rozana Abdul Rashid

Journal of Advanced Research in Applied Sciences and Engineering Technology, 2017;9(1):14-21.
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This paper reports the effect of microbending losses in single mode optical fiber
for pressure sensing system application. Several types of periodical corrugated
plates were fabricated, namely cylindrical-structured surface (Plate A) and
rectangular-structured surface (Plate B) with thicknesses of corrugated parts
were varied at 0.1 cm, 0.2 cm and 0.3 cm. Laser sources with excitation
wavelengths of 1= 1310 nm and 2= 1550 nm were launched at the first end
of the fiber. The values of losses were recorded by using an optical power
meter. It was clearly seen that the microbending losses were polynomially
increased with the increment of applied pressure and the thicknesses of
corrugated parts of Plate A and Plate B. The maximum microbending losses of
1.5185 dBm/kPa was resulted as SMF was coupled with corrugated plates B
with thicknesses of 0.3cm by using excitation wavelength of 1550nm. These
values reduced to 0.7628 dBm/kPa and 0.4014 dBm/kPa as the thicknesses
were decreased to 0.2cm and 0.1cm respectively. In comparison with a plain
plate which acted as a reference indicator, the maximum percentage of
microbending losses was obtained as 74.29 % for Plate A and 95.02 % for Plate
B. In conclusions, we successfully proved the ability of SMF as a pressure sensor
by manipulating the microbending losses experienced by the fiber. The
employment of 1550nm of laser wavelength results better sensitivity sensor
where the system able to detect large losses as the pressure applied on the
corrugated surfaces.

Matched MeSH terms: Lasers
Optical properties of InGaAs/GaAs multi quantum wells structure grown by molecular beam epitaxy

Mohd Sharizal Alias, Mohd Fauzi Maulud, Mohd Razman Yahya, Abdul Fatah Awang Mat, Suomalainen S

Sains Malaysiana, 2008;37:233-237.

Inclusive analysis on the optical characteristics of InGaAs/GaAs QW structure for 980 nm semiconductor laser operation is presented from experimental and theoretical point of view. The InGaAs/GaAs quantum well structure is grown by molecular beam epitaxy at different indium composition and quantum well thickness for optical characteristic comparison. Photoluminescence spectra from the measurement show that the spectrum is in good agreement with the simulation results. Detail simulation on the material gain for the InGaAs/GaAs quantum well as a function of carrier densities and operating temperature is also performed in order to optimize the semiconductor laser design for device fabrication.

Matched MeSH terms: Lasers, Semiconductor
Fulltext Retrofitting ancient timber glulam mortise & tenon construction joints through computer-aided laser cutting

Zhan Z, Wang C, Yap JBH, Loi MS

Heliyon, 2020 Apr;6(4):e03671.
PMID: 32382668 DOI: 10.1016/j.heliyon.2020.e03671

This study is aimed to rationalise and demonstrate the efficacy of utilising laser cutting technique in the fabrication of glulam mortise & tenon joints in timber frame. Trial-and-error experiments aided by laser cutter were conducted to produce 3D timber mortise & tenon joints models. The two main instruments used were 3D modelling software and the laser cutter TH 1390/6090. Plywood was chosen because it could produce smooth and accurate cut edges whereby the surface could remain crack-free, and it could increase stability due to its laminated nature. Google SketchUp was used for modelling and Laser CAD v7.52 was used to transfer the 3D models to the laser cutter because it is compatible with AI, BMP, PLT, DXF and DST templates. Four models were designed and fabricated in which the trial-and-error experiments proved laser cutting could speed up the manufacturing process with superb quality and high uniformity. Precision laser cutting supports easy automation, produces small heat-affected zone, minimises deformity, relatively quiet and produces low amount of waste. The LaserCAD could not process 3D images directly but needed 2D images to be transferred, so layering and unfolding works were therefore needed. This study revealed a significant potential of rapid manufacturability of mortise & tenon joints with high-quality and high-uniformity through computer-aided laser cutting technique for wide applications in the built environment.

Matched MeSH terms: Lasers
Fulltext Determination of the difference on color changes of watermelons by laser light backscattering imaging

Mohd Ali M, Hashim N, Bejo SK, Shamsudin R

J Food Sci Technol, 2017 Oct;54(11):3650-3657.
PMID: 29051660 DOI: 10.1007/s13197-017-2826-y

The potential of laser light backscattering imaging was investigated for monitoring color parameters of seeded and seedless watermelons during storage. Two watermelon cultivars were harvested and stored for 3 weeks with seven measuring storage days (0, 4, 8, 12, 15, 18, and 21). The color parameters of watermelons were monitored using the conventional colorimetric methods (L*, a*, b*, C*, H*, and ∆E*) and laser light backscattering imaging system. A laser diode emitting at 658 nm and 30 mW power was used as a light source to obtain the backscattering image. The backscattering images were evaluated by the extraction of backscattering parameters based on the mean pixel values. The results showed that a good color prediction was achieved by the seedless watermelon with the R2 are all above 0.900. Thus, the application of the laser light backscattering imaging can be used for evaluating the color parameters of watermelons during the storage period.

Matched MeSH terms: Lasers, Semiconductor
Fulltext 1700 nm and 1800 nm band tunable thulium doped mode-locked fiber lasers

Emami SD, Dashtabi MM, Lee HJ, Arabanian AS, Rashid HAA

Sci Rep, 2017 Oct 06;7(1):12747.
PMID: 28986584 DOI: 10.1038/s41598-017-13200-x

This paper presents short wavelength operation of tunable thulium-doped mode-locked lasers with sweep ranges of 1702 to 1764 nm and 1788 to 1831 nm. This operation is realized by a combination of the partial amplified spontaneous emission suppression method, the bidirectional pumping mechanism and the nonlinear polarization rotation (NPR) technique. Lasing at emission bands lower than the 1800 nm wavelength in thulium-doped fiber lasers is achieved using mode confinement loss in a specially designed photonic crystal fiber (PCF). The enlargement of the first outer ring air holes around the core region of the PCF attenuates emissions above the cut-off wavelength and dominates the active region. This amplified spontaneous emission (ASE) suppression using our presented PCF is applied to a mode-locked laser cavity and is demonstrated to be a simple and compact solution to widely tunable all-fiber lasers.

Matched MeSH terms: Lasers
Fulltext Improved Range Estimation Model for Three-Dimensional (3D) Range Gated Reconstruction

Chua SY, Guo N, Tan CS, Wang X

Sensors (Basel), 2017 Sep 05;17(9).
PMID: 28872589 DOI: 10.3390/s17092031

Accuracy is an important measure of system performance and remains a challenge in 3D range gated reconstruction despite the advancement in laser and sensor technology. The weighted average model that is commonly used for range estimation is heavily influenced by the intensity variation due to various factors. Accuracy improvement in term of range estimation is therefore important to fully optimise the system performance. In this paper, a 3D range gated reconstruction model is derived based on the operating principles of range gated imaging and time slicing reconstruction, fundamental of radiant energy, Laser Detection And Ranging (LADAR), and Bidirectional Reflection Distribution Function (BRDF). Accordingly, a new range estimation model is proposed to alleviate the effects induced by distance, target reflection, and range distortion. From the experimental results, the proposed model outperforms the conventional weighted average model to improve the range estimation for better 3D reconstruction. The outcome demonstrated is of interest to various laser ranging applications and can be a reference for future works.

Matched MeSH terms: Lasers
Fulltext Underwater Turbulence Detection Using Gated Wavefront Sensing Technique

Bi Y, Xu X, Chua SY, Chow EMT, Wang X

Sensors (Basel), 2018 Mar 07;18(3).
PMID: 29518889 DOI: 10.3390/s18030798

Laser sensing has been applied in various underwater applications, ranging from underwater detection to laser underwater communications. However, there are several great challenges when profiling underwater turbulence effects. Underwater detection is greatly affected by the turbulence effect, where the acquired image suffers excessive noise, blurring, and deformation. In this paper, we propose a novel underwater turbulence detection method based on a gated wavefront sensing technique. First, we elaborate on the operating principle of gated wavefront sensing and wavefront reconstruction. We then setup an experimental system in order to validate the feasibility of our proposed method. The effect of underwater turbulence on detection is examined at different distances, and under different turbulence levels. The experimental results obtained from our gated wavefront sensing system indicate that underwater turbulence can be detected and analyzed. The proposed gated wavefront sensing system has the advantage of a simple structure and high detection efficiency for underwater environments.

Matched MeSH terms: Lasers
Comparison of LED and LASER Colonoscopy About Linked Color Imaging and Blue Laser/Light Imaging of Colorectal Tumors in a Multinational Study

Yoshida N, Draganov PV, John S, Neumann H, Rani RA, Hsu WH, et al.

Dig Dis Sci, 2023 Oct;68(10):3943-3952.
PMID: 37558800 DOI: 10.1007/s10620-023-08057-2

INTRODUCTION: In light-emitting diode (LED) and LASER colonoscopy, linked color imaging (LCI) and blue light/laser imaging (BLI) are used for lesion detection and characterization worldwide. We analyzed the difference of LCI and BLI images of colorectal lesions between LED and LASER in a multinational study.
METHODS: We prospectively observed lesions with white light imaging (WLI), LCI, and BLI using both LED and LASER colonoscopies from January 2020 to August 2021. Images were graded by 27 endoscopists from nine countries using the polyp visibility score: 4 (excellent), 3 (good), 2 (fair), and 1 (poor) and the comparison score (LED better/similar/LASER better) for WLI/LCI/BLI images of each lesion.
RESULTS: Finally, 32 lesions (polyp size: 20.0 ± 15.2 mm) including 9 serrated lesions, 13 adenomas, and 10 T1 cancers were evaluated. The polyp visibility scores of LCI/WLI for international and Japan-expert endoscopists were 3.17 ± 0.73/3.17 ± 0.79 (p = 0.92) and 3.34 ± 0.78/2.84 ± 1.22 (p

Matched MeSH terms: Lasers
New tree height allometries derived from terrestrial laser scanning reveal substantial discrepancies with forest inventory methods in tropical rainforests

Terryn L, Calders K, Meunier F, Bauters M, Boeckx P, Brede B, et al.

Glob Chang Biol, 2024 Aug;30(8):e17473.
PMID: 39155688 DOI: 10.1111/gcb.17473

Tree allometric models, essential for monitoring and predicting terrestrial carbon stocks, are traditionally built on global databases with forest inventory measurements of stem diameter (D) and tree height (H). However, these databases often combine H measurements obtained through various measurement methods, each with distinct error patterns, affecting the resulting H:D allometries. In recent decades, terrestrial laser scanning (TLS) has emerged as a widely accepted method for accurate, non-destructive tree structural measurements. This study used TLS data to evaluate the prediction accuracy of forest inventory-based H:D allometries and to develop more accurate pantropical allometries. We considered 19 tropical rainforest plots across four continents. Eleven plots had forest inventory and RIEGL VZ-400(i) TLS-based D and H data, allowing accuracy assessment of local forest inventory-based H:D allometries. Additionally, TLS-based data from 1951 trees from all 19 plots were used to create new pantropical H:D allometries for tropical rainforests. Our findings reveal that in most plots, forest inventory-based H:D allometries underestimated H compared with TLS-based allometries. For 30-metre-tall trees, these underestimations varied from -1.6 m (-5.3%) to -7.5 m (-25.4%). In the Malaysian plot with trees reaching up to 77 m in height, the underestimation was as much as -31.7 m (-41.3%). We propose a TLS-based pantropical H:D allometry, incorporating maximum climatological water deficit for site effects, with a mean uncertainty of 19.1% and a mean bias of -4.8%. While the mean uncertainty is roughly 2.3% greater than that of the Chave2014 model, this model demonstrates more consistent uncertainties across tree size and delivers less biased estimates of H (with a reduction of 8.23%). In summary, recognizing the errors in H measurements from forest inventory methods is vital, as they can propagate into the allometries they inform. This study underscores the potential of TLS for accurate H and D measurements in tropical rainforests, essential for refining tree allometries.

Matched MeSH terms: Lasers
Seamless tuning range based-on available gain bandwidth in multiwavelength Brillouin fiber laser

Ajiya M, Mahdi MA, Al-Mansoori MH, Hitam S, Mokhtar M

Opt Express, 2009 Apr 13;17(8):5944-52.
PMID: 19365413

We experimentally demonstrate a simple widely tunable multiwavelength Brillouin/Erbium fiber laser that can be tuned over the entire C-band, thereby greatly improving the tuning range limitation faced by the previous Brillouin-erbium fiber laser architectures. Tuning range of 39 nm from 1527 nm to 1566 nm, which is only limited by the amplification bandwidth of the erbium gain was successfully achieved. At Brillouin pump wavelength of 1550 nm and 1480 nm laser pump and Brillouin pump powers of 130 mW and 2 mW respectively, all the generated output channels have peak power above 0 dBm, with the first output channel having a peak power of 8.52 dBm. The experimental set up that consists of only 4 optical components, is simple, devoid of the complex structure employed previously to enhance the tunability and feedback mechanism normally associated with multiwavelength Brillouin-erbium fiber laser sources. The generated output channels are stable, rigidly separated by 10 GHz (0.08 nm).

Matched MeSH terms: Lasers*
Investigation on the effect of EDFA location in ring cavity Brillouin-Erbium fiber laser

Hambali NA, Mahdi MA, Al-Mansoori MH, Abas AF, Saripan MI

Opt Express, 2009 Jul 06;17(14):11768-75.
PMID: 19582091

We have investigated the characteristics of Brillouin-Erbium fiber laser (BEFL) with variation of Erbium-doped fiber amplifier (EDFA) locations in a ring cavity configuration. Three possible locations of the EDFA in the laser cavity have been studied. The experimental results show that the location of EDFA plays vital role in determining the output power and the tuning range. Besides the Erbium gain, Brillouin gain also contributes to the performance of the BEFL. By placing the EDFA next to the Brillouin gain medium (dispersion compensating fiber), the Brillouin pump signal is amplified thereby generating higher intensities of Brillouin Stokes line. This efficient process suppresses the free running self-lasing cavity modes from oscillating in cavity as a result of higher Stokes laser power and thus provide a wider tuning range. At the injected Brillouin pump power of 1.6 mW and the maximum 1480 nm pump power of 135 mW, the maximum Stokes laser power of 25.1 mW was measured and a tuning range of 50 nm without any self-lasing cavity modes was obtained.

Matched MeSH terms: Lasers*
Fulltext In Vitro Mean Red Blood Cell Volume Change Induced by Diode Pump Solid State Low-Level Laser of 405 nm

Musawi MS, Jafar MS, Al-Gailani BT, Ahmed NM, Suhaimi FM, Suardi N

Photomed Laser Surg, 2016 May;34(5):211-4.
PMID: 26966989 DOI: 10.1089/pho.2015.4043

OBJECTIVE: This study was conducted to investigate the effects of low-level laser (LLL) doses on human red blood cell volume. The effects of exposure to a diode pump solid state (DPSS) (λ = 405 nm) laser were observed.
BACKGROUND DATA: The response of human blood to LLL irradiation gives important information about the mechanism of interaction of laser light with living organisms. Materials and methods Blood samples were collected into ethylenediaminetetraacetic acid (EDTA)-containing tubes, and each sample was divided into two equal aliquots, one to serve as control and the other for irradiation. The aliquot was subjected to laser irradiation for 20, 30, 40, or 50 min at a fixed power density of 0.03 W/cm(2). Mean cell volume (MCV) and red blood cell (RBC) counts were measured immediately after irradiation using a computerized hemtoanalyzer.
RESULTS: Significant decrease in RBC volume (p

Matched MeSH terms: Lasers, Solid-State; Lasers, Semiconductor
The effect of CO2 laser treatment on skin tissue

Baleg SM, Bidin N, Suan LP, Ahmad MF, Krishnan G, Johari AR, et al.

J Cosmet Dermatol, 2015 Sep;14(3):246-53.
PMID: 25817596 DOI: 10.1111/jocd.12142

The aim of this study was to evaluate the effects of multiple pulses on the depth of injury caused by CO2 laser in an in vivo rat model.

Matched MeSH terms: Lasers, Gas*
Effect of Photodynamic therapy and Er,Cr: YSGG laser on bond strength of bleached enamel to composite resin

Niazi FH, Qamar Z, Tanvir SB, Noushad M, Dossary OBA

Photodiagnosis Photodyn Ther, 2021 Sep;35:102405.
PMID: 34153543 DOI: 10.1016/j.pdpdt.2021.102405

OBJECTIVE: The purpose of the present study was bleached enamel reversal using conventional ascorbic acid (AA) and contemporary methods including Photodynamic therapy (PDT), Er, Cr: YSGG (ECL) on bond integrity to composite resin.
MATERIAL AND METHOD: Forty sound permanent mandibular premolars were collected from a dental clinical setting and disinfected. All forty samples were mounted vertically in a rubber mold exposing only the clinical crown. All samples were bleached using Opalescence Boost Professional Teeth Whitening. After the bleaching procedure, each sample was randomly allocated into four groups according to surface treatment. Samples in group 1 were treated with methylene blue photosensitizer (MBP). Samples in group 2 were exposed to 10% sodium ascorbate. Samples in group 3 were treated with Er, Cr: YSGG laser (ECL). Samples in group 4 were not treated (control). All Samples were treated with 37% phosphoric acid and a bonding agent was applied. A bulk-fill composite was cured to all specimens and all samples were treated in a thermocycler. Specimens were placed in a universal testing machine for shear bond strength (SBS) testing. Descriptive statistics were associated by analysis of variance (ANOVA) and Tukey's post hoc test maintaining level of significance (p<0.05) RESULTS: The lowest SBS scores were achieved in the bleached enamel (BE) group (15.25±1.745 MPa). Whereas, the highest bond integrity was attained by AA group (32.23±1.854 MPa). Samples treated with ECL (31.87±1.659 MPa) and AA (32.23±1.854) were comparable (p>0.05). Samples treated with PDT exhibited significantly different SBS (22.41±1.258) compared to other experimental groups CONCLUSION: ECL showed a reversal effect of BE compared to AA and has the potential to be used in clinical settings. BE reversal using MBP needs further investigation.

Matched MeSH terms: Lasers, Solid-State*
Evaluation of structural and compositional changes on the root surface exposed to diode laser (810 nm): An In-vitro study

Jayachandran D, Selvaraj S, Priya S, Kukkamalla MA, Senkalvarayan V

Indian J Dent Res, 2023;34(1):19-23.
PMID: 37417051 DOI: 10.4103/ijdr.ijdr_723_22

BACKGROUND: The laser therapy has been used as an adjuvant for conventional periodontal disease as they exhibit a bactericidal effect on scaling and root planning by its thermal and photo disruptive effects on the pathogens. This study focuses on the structural and compositional changes induced on the root surfaces of teeth following diode laser (DL) application with increasing quantum of exposure time.
OBJECTIVE: The objective of this study was to evaluate the structural and compositional changes on the root surface of extracted human permanent teeth after application of DLs (810 nm) with varying time interval.
MATERIALS AND METHODS: Twenty samples of single-rooted periodontally compromised extracted teeth were utilized for this study. Root planning was done and the roughness caused by the instrumentation was measured using profilometric analysis. Then, the samples were divided into four groups, with DL application time: Group 1 - laser application for 15 s, Group 2 - laser application for 30 s, Group 3 - laser application for 45 s, and Group 4 - laser application for 60 s. A scanning electron microscope was used to examine the cemental surface and energy-dispersive X-ray analysis software assesses the compositional changes of the teeth in each group.
RESULTS: This study reveals that on exposure of DL (810 nm) on the root surface when time of exposure increases, there were relative increases in surface irregularities and charring. There were significant changes in the chemical composition of the tooth surface.

Matched MeSH terms: Lasers, Semiconductor/therapeutic use
Fulltext Effect of Laser and Energy-based Device Therapies to Minimize Surgical Scar Formation: A Systematic Review and Network Meta-analysis

Yenyuwadee S, Achavanuntakul P, Phisalprapa P, Levin M, Saokaew S, Kanchanasurakit S, et al.

Acta Derm Venereol, 2024 Jan 08;104:adv18477.
PMID: 38189223 DOI: 10.2340/actadv.v104.18477

Utilization of lasers and energy-based devices for surgical scar minimization has been substantially evaluated in placebo-controlled trials. The aim of this study was to compare reported measures of efficacy of lasers and energy-based devices in clinical trials in preventing surgical scar formation in a systematic review and network meta-analyses. Five electronic databases, PubMed, Scopus, Embase, ClinicalTrials.gov, and the Cochrane Library, were searched to retrieve relevant articles. The search was limited to randomized controlled trials that reported on clinical outcomes of surgical scars with treatment initiation no later than 6 months after surgery and a follow-up period of at least 3 months. A total of 18 randomized controlled trials involving 482 participants and 671 postsurgical wounds were included in the network meta-analyses. The results showed that the most efficacious treatments were achieved using low-level laser therapy) (weighted mean difference -3.78; 95% confidence interval (95% CI) -6.32, -1.24) and pulsed dye laser (weighted mean difference -2.46; 95% CI -4.53, -0.38). Nevertheless, low-level laser therapy and pulsed dye laser demonstrated comparable outcomes in surgical scar minimization (weighted mean difference -1.32, 95% CI -3.53, 0.89). The findings of this network meta-analyses suggest that low-level laser therapy and pulsed dye laser are both effective treatments for minimization of scar formation following primary closure of surgical wounds with comparable treatment outcomes.

Matched MeSH terms: Lasers, Dye*
Fluorescent microscopy evaluation of diode laser effect on the penetration depth of turmeric (Curcuma longa) extract cream on skin tissues of Wistar rats

Astuti SD, Mawaddah A, Kusumawati I, Mahmud AF, Nasution AMT, Purwanto B, et al.

Lasers Med Sci, 2024 Feb 23;39(1):79.
PMID: 38393433 DOI: 10.1007/s10103-024-04020-3

The study investigates the effect of diode laser exposure on curcumin's skin penetration, using turmeric extraction as a light-sensitive chemical and various laser light sources. It uses an in vivo skin analysis method on Wistar strain mice. The lasers are utilized at wavelengths of 403 nm, 523 nm, 661 nm, and 979 nm. The energy densities of the lasers are 20.566 J/cm2, 20.572 J/cm2, 21.162 J/cm2, and 21.298 J/cm2, which are comparable to one another. The experimental animals were divided into three groups: base cream (BC), turmeric extract cream (TEC), and the combination laser (L), BC, and TEC treatment group. Combination light source (LS) with cream (C) was performed with 8 combinations namely 523 nm ((L1 + BC) and (L1 + TEC)), 661 nm ((L2 + BC) and (L2 + TEC)), 403 nm ((L3 + BC) and (L3 + TEC)), and 979 nm ((L4 + BC) and (L4 + TEC)). The study involved applying four laser types to cream-covered and turmeric extract-coated rat skin, with samples scored for analysis. The study found that both base cream and curcumin cream had consistent pH values of 7-8, within the skin's range, and curcumin extract cream had lower viscosity. The results of the statistical analysis of Kruskal-Wallis showed a significant value (p 0.05), while the treatment using BC and TEC showed a significant difference (p

Matched MeSH terms: Lasers, Semiconductor/therapeutic use
Comparative efficacy and safety of energy coagulation in radiation-induced hemorrhagic cystitis: A narrative review

Khern WC, Rajandram R, Raja Ram NK, Kuppusamy S

Investig Clin Urol, 2025 Mar;66(2):97-105.
PMID: 40047122 DOI: 10.4111/icu.20240288

To assess the efficacy and safety of using energy devices as treatment for radiation-induced hemorrhagic cystitis (RHC) and to determine the most suitable energy source, settings and techniques based on laser-tissue interaction. A search of Google Scholar, PubMed, and Web of Science databases was conducted uptil February 2024 to identify studies on use of energy devices for RHC. Additionally, ClinicalTrials.gov and the World Health Organization's ICTRP (International Clinical Trials Registry Platform) were searched for ongoing studies. We identified 10 studies fulfilling the search criteria using modalities including Nd:YAG laser, argon plasma coagulation, 980-nm diode laser, and potassium-titanyl-phosphate (KTP) laser. Across studies (n=137), majority (n=116, 84.7%) of RHC patients achieved hematuria resolution after one treatment session, with mean/median hematuria-free intervals of 11 to 16 months. Six patients (4.4%) were unresponsive and underwent cystectomy/urinary diversion. Total adverse events occurred in patients (30/139, 21.6%), including storage symptoms, recurrent hematuria, bladder stones and urinary retention, among others. Typical laser settings involved low power (<40 W), with either a pulse duration of 2-3 seconds or 10-40 milliseconds; some used continuous wave mode. Other standard practises include selective coagulation employed in a "painting" fashion and non-contact mode (3-5 mm). The treatment endpoints were hemostasis, involution of telangiectatic vessels and formation of pale well-circumscribed mucosal ulcer. Energy devices have considerable efficacy and safety to treat RHC patients and can be considered for refractory RHC and as an adjunct after initial management. The various properties of KTP laser confers an advantage over other energy devices.

Matched MeSH terms: Lasers, Solid-State/therapeutic use
Fulltext Fabrication of silver nanoparticles dispersed in palm oil using laser ablation

Zamiri R, Zakaria A, Ahangar HA, Sadrolhosseini AR, Mahdi MA

Int J Mol Sci, 2010;11(11):4764-70.
PMID: 21151470 DOI: 10.3390/ijms11114764

In this study we used a laser ablation technique for preparation of silver nanoparticles. The fabrication process was carried out by ablation of a silver plate immersed in palm oil. A pulsed Nd:YAG laser at a wavelength of 1064 nm was used for ablation of the plate at different times. The palm coconut oil allowed formation of nanoparticles with very small and uniform particle size, which are dispersed very homogeneously within the solution. The obtained particle sizes for 15 and 30 minute ablation times were 2.5 and 2 nm, respectively. Stability study shows that all of the samples remained stable for a reasonable period of time.

Matched MeSH terms: Lasers
Red-green-blue laser emissions from dye-doped poly(vinyl alcohol) films

Yap SS, Siew WO, Tou TY, Ng SW

Appl Opt, 2002 Mar 20;41(9):1725-8.
PMID: 11921803

A microscope slide acting as a passive waveguide was coated by three separate poly(vinyl alcohol) films that were doped with Coumarin 460, Disodium Fluorescein, and Rhodamine 640 perchlorate. On collinear pumping by a nitrogen laser, these dyes furnished primary red-green-blue laser emissions that were collected and waveguided by the microscope slide but exited from both ends. Frosting the waveguide exit introduced light scattering at the glass-air interface and spatially overlaid the red-green-blue laser emissions that emerged as a uniform white-light beam.

Matched MeSH terms: Lasers, Gas

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