Search

Transparent glass-ceramics based on Co2+:ZnO nanocrystals are synthesized in cobalt-doped glasses of the K 2 O-ZnO-Al 2 O 3 -SiO 2 system. Passive Q-switching of an Er, Yb:glass laser with 0.37 mJ/100 ns pulses at ∼1.54 μm is realized.

A new TOF camera design is presented based on a compact eye-safe actively Q-switched diode pumped Er:glass laser and a receiver system based on focal plane array of short wave infrared InGaAs PIN diodes with a special readout integration circuit and an image intensifier. The developed camera is operable for distances up to 4 kilometers with 10 frame/s and 2.5 m resolution. The camera could be applied for airborne and space geodesy location and navigation.

To evaluate the efficacy and side effects of 1550-nm fractional Er:Glass laser in treating atrophic acne scar.Thirty Chinese patients aged 18-65 with atrophic acne scars on both cheeks received a split-face treatment, one side with four sessions of treatment with fractional 1550-nm Er:Glass laser at 20-day interval and the other with topical asiaticoside cream application three times daily as control. Clinical response and side effects were evaluated by a dermatologist three weeks after each treatment and again 12 weeks after the last laser treatment. In addition, self-evaluation of satisfaction by the patients was done at the end of treatment.The study found that mean scores decrease after treatment was 5.65 ± 4.34 for the treated side and 1.23 ± 3.41 for the control side. The improvement in acne scars after the fractional Er:Glass laser 1550-nm treatment was more significant than the control side (p = 0.0001). The side effects were mainly local skin irritation and erythema, which disappeared within one week.The research results show that the fractional 1550-nm Er:Glass laser is an effective and safe treatment device for atrophic acne scars.

Temperature distribution is the key factor affecting the bonding quality in the glass/glass laser bonding process. In this work, the finite element method was used to establish three-dimensional (3D) numerical analysis model of the temperature field during bonding. Based on the result of the finite element analysis, the crucial parameters and their influences on the temperature distribution were discussed. In order to predetermine the necessary process parameter values for bonding, a nonlinear multiparameter fitting formula was established to predict the maximum temperature. The fitting model was validated experimentally by recording the maximum temperature during laser bonding via an infrared thermal imager.

The liquid confinement medium (LCM) and the free confinement medium (FCM) made by ourselves were used as confinement overlays of laser shock processing (LSP) respectively, stainless steel 304 was shocked by Nd:Glass laser. The parameters of LSP are the wavelength of 1.06μm, the pulse duration of 20ns, and output energy of 35~40J. The laser was focused on a spot of Ф5mm. Firstly, the profiles of shocked regions of samples were measured by Taylor Hobson admeasuring apparatus, in which two different confinement mediums are used by LSP. Secondly, the ruinous behavior of the free confinement overlays induced by laser shock wave is observed and analyzed. Analyzed and compared with the experiments results, it is discovered that the effects of LSP are different with using different confinement mediums.

Background Female pattern hair loss (FPHL) is the most common cause of hair loss in women, and its prevalence increases with advancing age. Affected women may experience psychological distress and social withdrawal. A variety of laser and light sources have been tried for treatment of hair loss, and some success has been reported. Objective The purpose of this study was to determine the efficacy and safety of a 1550 nm fractional erbium–glass laser in treatment of female pattern hair loss. Patients and methods Twenty eight ethnic South Korean patients with varying degrees of FPHL were enrolled in the study. Patients received ten treatments with a 1550 nm fractional Er:Glass Laser (Mosaic, Lutronic Co., Ltd, Seoul, South Korea) at 2-weeks intervals using the same parameters (5–10 mm tip, 6 mJ pulse energy, 800 spot/cm2 density, static mode). Phototrichogram and global photographs were taken at baseline and at the end of laser treatment, and analysed for changes in hair density and hair shaft diameter. Global photographs underwent blinded review by three independent dermatologists using a 7-point scale. Patients also answered questionnaires assessing hair growth throughout the study. All adverse effects were reported during the study. Results Twenty seven patients completed a 5-month schedule of laser treatment. One patient was excluded during treatment due to occurrence of alopecia areata. At the initial visit, mean hair density was 100 ± 14/cm2, and mean hair thickness was 58 ± 12 μm. After 5 months of laser treatment, hair density showed a marked increase to 157 ± 28/cm2 (P

Objective This study aimed to compare the clinical efficacies of 1550- and 1565-nm Er:glass lasers in the treatment of periorbital wrinkles and to evaluate histological changes after treatment. Methods Twenty patients received five treatments each at 3-week intervals. The right periorbital area was exposed to the 1550-nm Er:glass laser and the left periorbital area was exposed to the 1565-nm Er:glass laser. Clinical improvement was evaluated by two blinded physicians who assessed comparative photographs using a four-point scale at baseline and 3 months after the final treatments. Skin biopsies were performed in five volunteers before treatment and at 3 months after the final treatment. Results The mean improvement scores 3 months after treatment with the 1550- and 1565-nm Er:glass lasers were 2.25 ± 0.62 and 2.28 ± 0.59 respectively. Histological examination revealed increased epidermal thickening and decreased solar elastosis 3 months after the final laser treatments. Conclusions Both 1550- and 1565-nm Er:glass lasers are safe and effective modalities in the treatment of periorbital wrinkles with no significant differences between the two lasers.

BACKGROUND Fractional laser resurfacing is a new procedure for skin rejuvenation. We have found that it has a skin tightening effect in humans. OBJECTIVE To assess the mechanism of the skin tightening effect of fractional laser treatment in animals using histologic approaches. METHODS The dorsal skin of hairless guinea pigs was irradiated with a fractional 1,540-nm erbium glass laser. Biopsy specimens were taken serially from 0 hour until 1 year after irradiation and evaluated histologically. RESULTS Histologic evaluation indicated dermal remodeling within 2 months, in which regenerated collagen bundles and fibroblasts aligned in a horizontal direction, suggesting a traction stress on the dermal components. The treated part became less obvious over a period of more than 3 months by recovery of fine collagen bundles without fibrosis. CONCLUSION These results suggest that improvement of the tension in a horizontal direction is essential for skin remodeling and improvement of facial laxity using fractional laser resurfacing.

Pulse synchronisation with an accuracy of no worse than ±5 ns is demonstrated in passively Q-switched neodymium phosphate glass and Nd:YAG lasers. Two operating regimes are realised: the 'sub-threshold' regime (when the slave Nd:YAG laser does not generate a giant pulse if its passive Q switch is not irradiated by the master Nd:glass laser) and the 'above-threshold' regime (when the pulse irradiating the passive Q switch of the slave laser advances its generation).

We have developed preliminary conceptual laser system designs for the Laser ICF (Inertial Confinement Fusion) Fission Energy (LIFE) application. Our approach leverages experience in high-energy Nd:...

BACKGROUND Surgical scars are a common cosmetic problem that occurs in various surgical fields including dermatology. Diverse trials have been made to prevent this annoying scar formation. Recently, 585- and 595-nm pulsed dye laser irradiation presented satisfactory cosmetic outcome for the treatment of surgical scars. Other fractionated lasers or light devices were also applied for scar treatment. OBJECTIVE To determine the effectiveness and safety of a newly developed 1,550-nm fractional erbium–glass laser in the prevention of scar formation after total thyroidectomy. MATERIALS AND METHODS Twenty-seven ethnic South Korean patients with linear surgical suture lines after total thyroidectomy operation were treated with a 1,550-nm fractional erbium–glass laser. The same surgeon performed all of the operations using the same surgical techniques. Each patient was treated four times at 1-month intervals using the same parameters (5- × 10-mm spot size, 10 mJ, 1,500 spot/cm2, static mode). Initiation of the first irradiation was made approximately 2 to 3 weeks after the thyroidectomy. The scar prevention effects were evaluated each month for 6 months after thyroidectomy. Two kinds of assessment methods were applied in this evaluation. First, the Vancouver Scar Scale (VSS) was used. Second, three independent physicians gave a global assessment valuation to the final cosmetic results: poor (1), fair (2), good (3), or excellent (4). These results were compared with the surgical scars of a control group (patients who denied laser treatments and had no other treatments during the 6 months after total thyroidectomy by the same surgeon). RESULTS The average VSS score was lower in the laser treatment group. The global assessment also presented better cosmetic outcomes in the treatment group than in the controls. CONCLUSION A new 1,550-nm fractional erbium–glass laser may efficiently repress the formation and hypertrophy of thyroidectomy scars on the neck, and it can be safely applied in relatively dark Asian skin without noticeable adverse effects. CONCLUSION The authors have indicated no significant interest with commercial supporters.

1623 nm Er:YAP and 1648 nm Er:YAG lasers resonantly pumped by a solid state Er:glass laser operating at 1535 nm were investigated. Laser generation was reached for Er:YAP and two Er:YAG crystals with different Er ion concentration. The maximal output energies were 20 and 45 mJ for Er:YAP and Er:YAG laser systems, respectively.

Background and Objective Fractional photothermolysis is a popular treatment option for photodamaged skin and other cutaneous conditions. Recently, successful improvement in melasma has been achieved with this laser system. We undertook this study to evaluate the ultrastructural changes associated with fractional laser treatment of melasma. Study Design/Materials and Methods Ten subjects with skin types III and IV and a clinical diagnosis of epidermal melasma were treated with a 1,550-nm erbium:glass laser delivering light in a fractional manner (Fraxel SR 750, Reliant Technologies, Inc., Mountain View, CA) every 2 weeks for a total of four sessions. Biopsies were obtained from all subjects both before treatment and at 3 months following the final treatment. All biopsies were analyzed by light and electron microscopy for treatment-induced changes. In addition, a secondary endpoint of the study was to assess for clinical improvement in melasma following fractional resurfacing. This assessment was performed by the investigator using pre- and post-treatment photographs. Results Light microscopy on post-treatment specimens showed a relative decrease in melanocytes compared to the pre-treatment ones. Post-treatment electron microscopy revealed fewer melanocytes and a relative absence of melanin in the surrounding keratinocytes compared to pre-treatment specimens. In addition, six subjects with skin type III were determined to have good improvement, whereas four subjects with skin type IV had fair improvement, as assessed by the investigator. Conclusion Post-treatment ultrastructural changes are consistent with an elimination process and may help to explain clinical improvement following laser treatment. Lesers Surg. Med. 40:134–138, 2008. © 2008 Wiley-Liss, Inc.

BACKGROUND The erbium:glass laser is approved to treat inflammatory acne on the back. OBJECTIVE This aim of this study was to evaluate the use of the 1,540-nm erbium:glass laser in the treatment of moderate to severe inflammatory acne on the face. METHODS AND MATERIALS An erbium:glass laser (Aramis, Quantel Medical, Clermont-Ferrand, France) was used to treat 15 patients with moderate to severe acne four times at 2-week intervals. Active lesions were first treated with six pulses at 10 J/cm2. The entire face was then treated with a single pass using bursts of four pulses at 10 J/cm2. Sebum measurements were performed. Six patients continued in a double-arm study to determine whether an additional treatment at 6 months would prolong the lesion-free period. Final evaluation was at 9 months. RESULTS At 6-month follow-up, patients rated improvement as 68%, and the mean investigator improvement assessment was 78%. Sebum measurements did not change. No patients required anesthesia, and no side effects were observed. A single retreatment session 6 months after the initial course held clearance at 80% at 9-month follow-up, whereas patients without retreatment had 72% clearance. CONCLUSION Treatment of inflammatory facial acne with the 1,540-nm erbium:glass laser is effective and relatively painless. Papules, pustules, and nodules all respond well to therapy. Additional treatment sessions may prolong the lesion-free period, and maintenance therapy should be included as a part of the treatment course.

The inuence of the cavity trapped amplied luminescence (CTAL) on the threshold, power and dynamic characteristics of Er, Yb : glass lasers with end and side diode pump congurations has been studied. The CTAL loss coefcient has been evaluated using the luminescence balance equation. The inverse proportion dependence of the CTAL loss coefcient on the cavity length has been revealed. It has been shown that amplication of luminescence in the laser cavity leads to a signicant increase of the threshold pump power (»3n5 times). The Er, Yb : glass laser generation dynamics has been modelled taking into account the luminescence evolution beginning with the onset of the diode pumping pulse. Depending on the diode pumping pulse amplitude, the increase or decrease of the Er, Yb : glass laser pulse generation delay can be observed.

As compared with ablative fractional CO2 laser, ablative fractional erbium-doped yttrium aluminum garnet (Er:YAG) laser is considered to be a more suitable treatment option for photoaged skin in Asians due to the lower incidence of postinflammatory hyperpigmentation.To compare the efficacy and safety of ablative fractional Er:YAG laser (ablative fractional resurfacing [AFR]) and nonablative fractional 1550-nm Er:glass laser (non-AFR [NAFR]) in the treatment of photoaging.This was a prospective, randomized, double-blinded comparative study. In three sessions, at four-week intervals, 19 patients received Er:YAG AFR, and 15 patients received Er:glass NAFR. Pigmentation, uneven tone/erythema, wrinkles and overall features of photoaging were scored. Patient satisfaction, adverse effects and pain scores were recorded. Melanin and erythema indexes were measured.Reductions in pigmentation and uneven tone/erythema scores were significantly greater after Er:YAG AFR, while wrinkle score reduction was significantly greater after Er:glass NAFR. Physician and patient assessments for the overall features showed greater improvement in the Er:glass NAFR. Treatment-related pain or adverse events were less in the Er:YAG AFR.Both Er:YAG AFR and Er:glass NAFR are effective and safe and could be used in a complementary manner for treating photoaged Asian skin.

Purpose. Early postoperative fractional laser treatment has been used to reduce scarring in many institutions, but the most effective energy parameters have not yet been established. This study sought to determine effective parameters in the treatment of facial laceration scars.Methods. From September 2012 to September 2013, 57 patients were enrolled according to the study. To compare the low and high fluence parameters of 1,550 nm fractional erbium-glass laser treatment, we virtually divided the scar of each individual patient in half, and each half was treated with a high and low fluence setting, respectively. A total of four treatment sessions were performed at one-month intervals and clinical photographs were taken at every visit.Results. Results were assessed using the Vancouver Scar Scale (VSS) and global assessment of the two portions of each individual scar. Final evaluation revealed that the portions treated with high fluence parameter showed greater difference compared to pretreatment VSS scores and global assessment values, indicating favorable cosmetic results.Conclusion. We compared the effects of high fluence and low fluence 1,550 nm fractional erbium-glass laser treatment for facial scarring in the early postoperative period and revealed that the high fluence parameter was more effective for scar management.

Acne treatment by a mid-infrared laser may be unsatisfactory due to deeply situated acne-affected sebaceous glands which serve as its target. Skin manipulation by vacuum and contact cooling may improve laser-skin interaction, reduce pain sensation, and increase overall safety and efficacy. To evaluate the safety and efficacy of acne treatment using an integrated cooling-vacuum-assisted 1540-nm erbium:glass laser, a prospective interventional study was conducted. It included 12 patients (seven men and five women) suffering from mild-to-moderate acne vulgaris. The device utilizes a mid-infrared 1540-nm laser (Alma Lasers Ltd. Caesarea, Israel), which is integrated with combined cooling-vacuum-assisted technology. An acne lesion is initially manipulated upon contact by a vacuum-cooling-assisted tip, followed by three to four stacked laser pulses (500-600 mJ, 4 mm spot size, and frequency of 2 Hz). Patients underwent four to six treatment sessions with a 2-week interval and were followed-up 1 and 3 months after the last treatment. Clinical photographs were taken by high-resolution digital camera before and after treatment. Clinical evaluation was performed by two independent dermatologists, and results were graded on a scale of 0 (exacerbation) to 4 (76-100 % improvement). Patients' and physicians' satisfaction was also recorded. Pain perception and adverse effects were evaluated as well. All patients demonstrated a moderate to significant improvement (average score of 3.6 and 2.0 within 1 and 3 months, respectively, following last treatment session). No side effects, besides a transient erythema, were observed. Cooling-vacuum-assisted 1540-nm laser is safe and effective for the treatment of acne vulgaris.

Acne scars are often a permanent disfiguring sequel of acne vulgaris. Although many treatment modalities are available, they are often non satisfactory for all patients.To determine the effectiveness and safety of fractional 1540 nm erbium_glass laser treatment of facial acne scars in Iraqi patients.Twenty one patients were enrolled in this prospective clinical study. Three sessions of the 1540 nm erbium glass laser were applied at 2-week intervals. The patients were assessed at 1, 3, and 6 months after the last session. The effect of treatment was assessed by objective (Sharquie scoring system for grading acne scarring and visual analog scale) and subjective (patient satisfaction) methods.Two patients were defaulted. Eleven patients (57.9%) showed improvement from moderate to mild grade, and no grade changes were detected in eight patients (42.1%). The mean score of the visual analog scale prior to treatment was 8.61 ± 0.86 and decreased to 6.15 ± 1.28 (P = 0.037). Ten patients were satisfied to varying degrees. No significant side effects were noted.Non-ablative fractional 1540 nm erbium glass laser is an effective and safe method to treat acne scars and represent good alternative for patients who cannot use the ablative methods because of its longer downtime.

Striae distensae are atrophic dermal scars associated with psychosocial stress. Several treatments have been used but there is no gold standard until now. Fractional photothermolysis has been described as a successful and safe method to treat scars. In this description, we report 4 patients (Fitzpatrick phototype IV) who developed striae distensae after long-term use of topical corticosteroids and were successfully treated with fractional nonablative 1540 nm Erbium: glass laser.

We obtained single frequency laser pulses with enery of 1.67-J and duration of 310-ps based on the nonfocusing-pumped stimulated Brillouin scattering. A high-power Nd:glass laser system delivers 3-ns super-Gaussian-shaped pulses is used as the light-source.

Laser shock processing (LSP) is a new technology for surface strengthening holes. In this procedure, the choice of laser parameters is essential. The present paper investigates a method for optimising the laser parameters in laser shock processing of holes. Based upon this method, a series of laser shocking experiments were performed using a Q switched neodymium glass laser. The fatigue test results show that the fatigue life of a hole can be greatly increased after LSP. The average fatigue life of a laser shocked hole is 2·2 times longer than that without laser treatment.

Background:. Nonablative remodeling has recently been proposed as a new antiaging treatment with no downtime. This technique could greatly benefit the increasing numbers of patients who are looking for new and efficient techniques, with a minimum of discomfort. Materialsheading. and methods. The 1.54 μm wavelength has been proposed for this application because this wavelength is well absorbed by water yet virtually not at all by melanin, allowing deep penetration into the skin. To protect the epidermis during laser irradiation, a cooling system (+58C) uses a sapphire window (purified tetrafluoroethane circulates in a pipe around the sapphire) directly applied to the skin through which the laser pulse may be fired. Results. Several clinical trials have been published and have demonstrated that clinical improvement was correlated with data from ultrasound imaging, histology, and profilometry. A recent trial on the forehead and neck yielded additional data on elasticity measured by echorheometry. Conclusions. The 1.54 μm laser is safe and effective for remodeling in all of these published studies. Remodeling requires months to achieve its goal, and the kind of improvement that can be expected should be explained to the patient. Long-term follow-up showed that the improvement increased after each treatment and lasted for months after the final session.

A 120 TW/36 fs laser system based on Ti:sapphire chirped-pulse amplification (CPA) has been successfully established in our lab. The final four pass Ti:sapphire amplifier pumped by an energetic single-shot Nd:YAG—Nd:glass laser was designed and optimized. With 24 J/8 ns pump energy at 532 nm, 300 mJ/220 ps chirped pulse was amplified to 5.98 J in this amplifier, and a total saturated gain of ∼20 was achieved. The focused intensity of compressed beam could reach to 10 20 W/cm 2 with the M 2 of ∼2.0.

BACKGROUND AND OBJECTIVES Terawatt (TW) lasers have become commonplace since the development of the chirped-pulse amplification method using Ti:sapphire and Nd:glass laser rods. We have measured the minimum visible lesion (MVL) thresholds for porcine1The animals involved in this study were procured, maintained, and used in accordance with the Federal Animal Welfare Act and the "Guide for the Care and Use of Laboratory Animals" prepared by the Institute of Laboratory Animal Resources-National Research Council. Brooks City-Base, TX has been fully accredited by the Association for Assessment and Accreditation of Laboratory Animal Care, International (AAALAC) since 1967. (Yucatan mini-pig) skin using TW laser pulses. STUDY DESIGN/MATERIALS AND METHODS Our system produced laser pulses at 810 nm and sub-50 femtoseconds. These 1-2 TW laser pulses created multiple self-focusing (SF) filaments during propagation and were directed on the flanks of mini-pigs under anesthesia. We measured the pulse energies necessary to determine the ED(50) skin damage thresholds. RESULTS The MVL ED(50) threshold at 1 hour was 8 mJ and increased to 21 mJ after 24 hours. Histological sections were obtained after 1-hour and 24-hour readings. CONCLUSIONS The damage patterns on the skin indicated the number of filaments in the laser pulse. Many of the pulses produced only superficial damage that disappeared in 24 hours and that nearly three times the pulse energy was required to cause subdural or cellular damage. With further research, non-thermal tissue ablation using TW laser pulses could provide a viable alternative to current techniques of laser use in dermatology.

Photoinduced changes of the piezooptical effects were discovered in the ZnO crystalline films doped by Cu. The photoexcitation was performed by the Er 3+ doped 10 ns glass laser at wavelength 1540 nm. The piezooptical effect was determined for the diagonal tensor component at 1150 nm. A nonlinear dependence of the output piezooptical response versus the photoinducing power density was established. The effect was completely reversible and disappears within the several second after the switching off of the photoinduced treatment. The possible explanation of the observed effect is given within a framework of the possible changes of Cu aggregates which is manifested through the changes of photoluminescence.

On the basis of theoretical results describing the propagation of short acoustic pulses in relaxation media, the temporal characteristics of a signal that carry the information on the first five moments of the relaxation time spectrum (RTS) are determined. The measurement of these characteristics forms the basis of the proposed variant of pulsed acoustic spectroscopy of relaxation media. An experimental setup was developed in which short acoustic pulses were excited by a neodymium glass laser. Test measurements of RTS moments for an acetic acid, the liquid with a single relaxation time, are carried out.

A new laser-driven flyer system is developed for use with the GEKKO/HIPER high-power glass laser system. The system employs an 8-μm three-layered flyer target and a new optical system for flyer velocity measurement, and is demonstrated to be capable of accelerating the flyer to approximately 23 km/s at 1031 J laser energy while maintaining a very flat shape. This is one of the highest flyer velocities reported to date, and shows the efficiency and utility of laser-driven flyer techniques in the study of material dynamics.