High stability and low noise laser-diode end-pumped Nd:YAG ceramic passively Q-switched laser at 1123 nm based on a Ti_(3)C_(2)T_(x)-PVA saturable absorber

We report a high repetition frequency, high power stability and low laser noise laser-diode(LD) end-pumped Nd: YAG ceramic passively Q-switched laser at 1123 nm based on a Ti_(3)C_(2)T_(x)-polyvinyl alcohol(PVA) film as a saturable absorber(SA). A Brewster polarizer(BP) and a birefringent crystal(BC) are incorporated to enable frequency selection and filtering for the passively Q-switched 1123 nm pulsed laser to improve the power stability and reduce the noise. When the pump power is 5.1 W, an average output power of 457.9 m W is obtained, corresponding to a repetition frequency of 1.09 MHz,a pulse width of 56 ns, a spectral line width of 0.65 nm, a power instability of ±0.92%, and a laser noise of 0.89%.The successful implementation of the “Ti_(3)C_(2)T_(x)-PVA film passively Q-switching” combined with “frequency selection and filtering of BP + BC” technology path provides a valuable reference for developing pulsed laser with high repetition frequency, high stability and low noise.

Passively Q-Switched Nd,Cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3μm

A diode-end-pumped Q-switched high-efficiency Nd, Cr：YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained.

Continuous-Wave and Actively Q-Switched Diode-Pumped Er:LuAG Ring Laser at 1650 nm

We demonstrate a cw and actively Q-switched Er：LuAO laser resonantly dual-end-pumped by 1532nm fibre- coupled laser diodes. A maximum cw output power of 1.9W at 1650.3nm is obtained at a pump power of 25.5 W, corresponding to a slope efficiency of 43.3 %. In the Q-switched regime, the maximum pulse energy of 3.51 mJ is reached at a pulse repetition rate of 100 Hz, a pulse duration of 90.5ns and a pump power of 25.5 W. At the repetition rate of 400 Hz, the output energy is 2.12m J, corresponding to a pulse duration of 125.4 ns.

High-Power Passively Q-Switched Nd:YAG Laser at 1112 nm with a Cr^(4+):YAG Saturable Absorber

A high-power passively Q-switched Nd：YAG laser operating at lll2nm with Cr4＋：yAO as a saturable absorber is demonstrated. Under 808 nm diode-direct pumping, the maximum average output power of 2.73 W is achieved at the pump power of 16.65 W, corresponding to an optical-to-optical conversion efficiency of 16.4%. At the same time, the pulse width, pulse repetition rate, single pulse energy and peak power are 27.2ns, 9 kHz, 303.3#3 and 11.2kW, respectively. As far as we know, the result gives the highest average output power at 1112nm generated by an 808 nm diode-end-pumped Nd：YAG laser.

Efficient Diode-Pumped Actively Q-Switched Ceramic Nd:YAG/YVO4 Raman Laser Operating at 1657 nm

A diode-pumped actively Q-switched Raman laser is demonstrated, with YV04 employed as Raman active medium, based on a ceramic Nd：YAG laser operating at 1444nm. The first-stokes Raman generation at 1657nm is achieved. A maximum output power of as high as 612mW is obtained under a pump power of 20. 7 W and at a pulse repetition frequency rate of 20kHz, corresponding to an optical-to-optical conversion efficiency of 3%.

755 nm皮秒激光治疗不同类型儿童色素增加性皮肤病的临床研究

目的:观察755 nm皮秒激光治疗不同类型儿童色素增加性皮肤病的临床疗效。方法:选取2021年1月-2022年2月于笔者医院应用755 nm皮秒激光治疗的色素增加性皮肤病患儿85例(包括雀斑25例,咖啡斑21例,太田痣20例,文身19例),针对不同的病变类型采用不同的治疗参数,疗程根据皮损的性质而定,治疗后观察临床疗效及不良反应。结果:经过1~6次755 nm皮秒激光治疗后,雀斑、咖啡斑、太田痣、文身患儿的临床总有效率分别为100.00%、85.71%、100.00%、100.00%,各类型临床疗效差异无统计学意义(P>0.05);治疗后各类型皮肤色斑定量评价数据均有显著改善,差异均有统计学意义(P<0.05)。各类型治疗期间均未出现严重不良反应。结论:应用755 nm皮秒激光治疗不同类型儿童色素增加性皮肤病疗效显著,且安全性良好,值得临床推广。

IPL联合Q开关755 nm激光治疗太田痣疗效分析

目的:探讨分析应用强脉冲光(Intense pulsed light,IPL)联合Q开关755 nm激光治疗太田痣患者70例的疗效。方法:选取2020年1月-2021年12月笔者医院收治的太田痣患者70例,简单随机分组为观察组(n=35)和对照组(n=35)。对照组予以IPL治疗,观察组在对照组基础上联合Q开关755 nm激光治疗。比较两组临床疗效、皮肤屏障功能[皮脂含量、角质层含水量和经表皮水分流失值(Trans epidermal water loss,TEWL)]、美观度[皮肤黑素指数(Melanin Index,MI)和红斑指数(Erythema index,EI)]和不良反应。结果:观察组治疗后总有效率(97.14%)高于对照组(82.86%),差异有统计学意义(P<0.05)。治疗后,两组患者皮脂含量、角质层含水量均升高,但观察组较对照组低,差异有统计学意义(P<0.05);治疗后,两组患者TEWL均降低,但观察组较对照组高,差异有统计学意义(P<0.05)。治疗后,两组患者MI、EI均降低,且观察组更低,差异有统计学意义(P<0.05)。两组患者治疗期间不良反应发生率比较差异无统计学意义(P>0.05)。结论:IPL联合Q开关755 nm激光可提高太田痣治疗效果和美观度,但对于皮肤屏障功能缺乏明显的保护效果。

Efficient Nd:YVO4 laser in-band pumped by wavelength-locked 913.9-nm laser diode and Q-switch operation

An efficient 1064-nm Nd：YVO_4laser in-band pumped by a wavelength-locked laser diode（LD） at 913.9 nm was demonstrated. The maximum continuous wave（CW） output power of 23.4 W at 1064 nm was realized with the incident pump power of 40 W, corresponding to a total optical-to-optical efficiency of 58.5%. This is to the best of our knowledge the highest total optical-to-optical efficiency and output power of Nd：YVO_4laser in-band pumped by a 913.9-nm laser diode.The Q-switched operation of this laser was also investigated. Through a contrast experiment of pumping at 808 nm, the experimental results showed that an Nd：YVO_4laser in-band pumped by a wavelength-locked LD at 913.9 nm had excellent pulse stability and beam quality for high repetition rate Q-switching operation.

Er^3+,Yb^3+:glass-Co^2+:MgAl2O4 diffusion bonded passively Q-switched laser

A Co^2＋：spinel passively Q-switched erbium-ytterbium-phosphate glass bonded laser pumped at 940 nm is reported.A pulse energy of 210 μJ, a peak power over 70 kW, and beam quality M-2 parameter of 1.2 are obtained under a pump power of 235 mW. An unbonded laser output experiment with the same dimension of the active material and the saturable absorber as the bonded laser output experiment is carried out. The reason why the output in the bonded laser is improved is determined.

755 nm皮秒激光联合微针治疗雀斑伴黄褐斑的Canfield VISIA系统色斑残留评分影响

目的探析755 nm皮秒激光联合微针治疗雀斑伴黄褐斑的临床疗效,及对症状消退时间的影响。方法以我院开展755 nm皮秒激光联合微针治疗的时间(2021年1月)为截点,2020年1月至2020年12月收治的62例雀斑伴黄褐斑患者为对照组(采用微针治疗),2021年1月至2021年12月收治的62例雀斑伴黄褐斑患者为观察组(采用755 nm皮秒激光联合微针治疗)。比较两组治疗前后的黄褐斑面积及严重程度(MASI)评分、治疗后的Canfield VISIA系统色斑残留评分、症状消退时间(色斑消退时间、黄褐斑消退时间)、不良反应及临床疗效。结果观察组治疗后的MASI评分、色斑残留评分均低于对照组,所需色斑消退时间、黄褐斑消退时间短于对照组,差异有统计学意义(P<0.05)。观察组不良反应总发生率与对照组相比无明显差异,差异无统计学意义(P>0.05)。观察组总有效率高于对照组,差异有统计学意义(P<0.05)。结论755 nm皮秒激光联合微针治疗在雀斑伴黄褐斑中能达较理想的治疗效果,能促进色斑、黄褐斑的消退,且安全度高、耐受良好,值得在临床中推广应用。

Q开关532 nm与755 nm激光治疗咖啡斑的疗效对比

本中心回顾性研究咖啡斑患者84例,随机给予Q开关532 nm和755 nm激光治疗,观察临床效果。结果显示,Q开关532 nm激光治疗36例,痊愈10例(27. 8%),显效10例(27. 8%),有效8例(22. 2%),无效8例(22. 2%); Q开关755 nm激光治疗48例,痊愈14例(29. 2%),显效13例(27. 1%),有效11例(22. 9%),无效10例(20. 8%),84例患者总有效率78. 6%。术后半年随访,色素沉着9例,色素减退3例,复发9例。Q开关激光治疗形状不规则的咖啡斑有效率为79. 5%,治疗形状规则的咖啡斑有效率为52. 5%,两组治疗的有效率差异有统计学意义(P <0. 05),Q开关532 nm激光和Q开关755 nm激光对咖啡斑的治疗效果无显著的统计学差异(P> 0. 05)。以上结果表明,Q开关532 nm激光和Q开关755 nm激光对咖啡斑有明确的治疗效果,且外形不规则的咖啡斑治疗效果好。

755nm皮秒激光仪平光透镜与Focus蜂巢透镜联合应用治疗黄褐斑

目的:观察755 nm皮秒激光仪平光透镜与Focus蜂巢透镜联合应用治疗黄褐斑的临床疗效及不良反应。方法:对36例黄褐斑患者,联合应用755 nm皮秒激光仪平光透镜和Focus蜂巢透镜治疗,每4周治疗1次,6次为1个疗程。先用平光透镜对黄褐斑区域治疗1遍,能量密度0.4 J/cm^2,光斑直径8 mm,频率5 Hz, 后用Focus蜂巢透镜以同样参数再治疗1遍。治疗后随访12周。疗程结束后进行黄褐斑面积及严重程度指数(MASI)评分与患者自我满意度评价,记录不良反应,观察随访情况,并进行统计学分析。结果:治疗前、治疗6次后及治疗结束后12周MASI评分分别为(11.17±5.29)、 (4.63±3.05)、 (5.11±3.23);治疗6次后MASI评分下降率为(64±7)%,治疗结束后12周为(61±6)%;治疗6次后与结束后12周的平均MASI评分均低于治疗前,差异有统计学意义(P<0.05);治疗结束后12周平均MASI评分比治疗6次后略有升高,但差异无统计学意义(P>0.05)。Fitzpatrick III型皮肤患者MASI评分下降率为(68±8)%,高于IV型患者的(56±6)%,差异有统计学意义(P<0.05)。治疗6次后患者满意率为94.4%,治疗结束后12周为88.9%。而且绝大多数患者皮肤肤质比治疗前更细腻紧致,细纹和毛孔粗大得到改善。所有患者均无明显不良反应发生。结论:755 nm皮秒激光仪平光透镜与Focus蜂巢透镜联合应用治疗黄褐斑起效快,不良反应少,复发率低,患者满意度高,是有效的治疗新方案。

Q开关755nm激光治疗太田痣的临床疗效及其相关因素分析

目的回顾性分析Q开关755nm激光治疗太田痣的疗效及其影响因素。方法对2014年1月-2015年12月就诊于我科的83例太田痣患者使用Q开关755nm激光进行治疗，根据治疗前后照片进行对比分析。结果83例太田痣患者经1-6次治疗，有效12例，显效27例，痊愈44例，总有效率100％。发病年龄与疗效呈负相关（r=-0．256，P〈0．05），皮损颜色与疗效呈负相关（r=-0．598，P〈0．05），治疗次数与疗效呈正相关（r=0．700，P〈0．05），病程、皮损面积及治疗时能量与疗效无统计学意义（P〉0．05）。结论Q开关755nm激光治疗太田痣安全、有效，治疗次数、皮损颜色及发病年龄对疗效有影响，且治疗次数影响最大。

光子嫩肤技术联合Q开关755nm翠绿宝石激光治疗皮肤色素性疾病的疗效分析

目的分析光子嫩肤联合Q开关755nm翠绿宝石激光在皮肤色素性疾病治疗中的应用价值。方法将112例皮肤色素增加性疾病患者分成对照组、观察组,给予单纯Q开关755nm翠绿宝石激光治疗、光子嫩肤联合755nm翠绿宝石激光治疗。结果观察组总有效率高于对照组(P<0.05);观察组治疗后生活质量高于对照组(P<0.05);光子嫩肤治疗后,患者局部皮肤发红,部分患者可见水肿,多于1d内自行消退;755nm翠绿宝石激光治疗后可见红肿、起泡等反应,起泡经穿刺抽液、外用抗生素软膏后可消退;红肿可于3d内自行消退。结论皮肤色素性疾病治疗中,光子嫩肤联合Q开关755nm翠绿宝石激光治疗的显效速度较快,有助于提升皮肤色素性疾病患者的生活质量。

LD-pumped acousto-optic 2-switched Pr:YLF pulsed laser at 604 nm

We demonstrated an actively acousto-optic Q-switched pulsed laser based on Pr:YLF at 604 nm.A 604 nm continuous-wave(CW)laser with a maximum output power of 3.84 W was achieved for the first time,to the best of our knowledge.The Q-switched laser with a maximum average output power of 0.384 W,a narrowest pulse duration of 44.5 ns,a maximum single pulse energy of~64.1μJ,and a maximum peak power of~1.44 kW was obtained at a repetition rate of 6 kHz.As far as we know,this was the first report of such a narrow pulse duration,high-power,and high-energy Q-switched pulsed laser at604 nm.The beam quality factors M_x~2and M_y~2were measured to be 2.87 and 2.40,respectively.The results show that acousto-optic Q-switching is a promising method for obtaining pulsed lasers.

Double Q-switched 946 nm laser with MgO：LN electro-optic crystal and MoSe2 saturable absorber

We report a double Q-switched 946 nm laser with a magnesium-oxide-doped LiNbO3 （MgO：LN） electro-optic （EO） crystal and a monolayer molybdenum diselenide （MoSe2） saturable absorber （SA）. A pulsed laser diode side-pumped long neodymium-doped yttrium aluminum garnet rod （φ3×65 mm） is used as the gain medium. Large pulse energy up to 3.15 mJ and peak power up to 346 kW are generated at the repetition rate of 550 Hz, corresponding to the beam quality factors of Mx^2=3.849, My^2=3.868. Monolayer MoSe2 nanosheets applied in the experiment would be a promising SA for a passive Q-switching operation.

Clinical Evaluation of a Novel Blended Mode Diode Laser for Hair Removal

Introduction: Photoepilation by lasers is a popular procedure in aesthetic dermatology for removing unwanted body and facial hair. The use of the most appropriate laser wavelength is crucial as it affects treatment depth and melanin absorption. The three commonly used hair removal lasers are of specific wavelengths: 755 nm, 810 nm, and 1064 nm, each preferred certain types of skin and hair characteristics. The current evaluation reports the safety and efficacy of unique blended modes 755/810 nm and 810/1064 nm diode lasers for hair removal. Methods: Hair removal results from 50 patients treated with the 755/810 nm handpiece and 50 patients treated with the 810/1064 nm handpiece were gathered from a few clinics. 3 treatments on various body areas were conducted 6 weeks apart and patients were followed up with 6 months after the last treatment. Results were evaluated by baseline, follow-up photographs, and hair counts. Results: Treatment area photos demonstrated hair reduction in the treated body and facial areas. Average hair count reduction at 6 months follow-up was 84% for the 755/810 nm handpiece and 81% for the 810/1064 nm handpiece. No significant or unexpected adverse events were detected in any of the patients. Conclusions: The novel blended mode hair removal diode lasers are proven to be safe and effective for hair removal in facial and body areas for patients of various skin types and hair characteristics.

Line-narrowed electro-optic periodically-poled-lithium-niobate Q-switched laser with intra-cavity optical parametric oscillation using a grazing-incidence grating

We report a line-narrowed electro-optic periodically-poled-lithium-niobate （PPLN） Q-switched laser with intra-cavity optical parametric oscillation using a grazing-incidence grating, producing 8-ns, 5-#J pulses at 10-kHz repetition rate when pumped with a 10-W diode laser at 808 rim. The output wavelength is centered at 1554.3 nm with a 0.03-nm spectral width. Wavelength tuning is achieved by rotating a mirror and changing the crystal temperature.

不同波长激光对太田痣治疗的影响

本研究对比Q开关翠绿宝石755 nm激光和Q开关Nd:YAG1 064 nm激光治疗太田痣的疗效和差别,探讨分析原因。分别用Q开关翠绿宝石755 nm激光和Q开关Nd:YAG1 064 nm激光治疗637例太田痣患者,观察患者治疗前后疗效,根据色素减轻百分比进行评定。结果表明Q开关翠绿宝石755 nm激光和Q开关Nd:YAG1 064 nm激光均能安全有效的治疗太田痣,Q开关翠绿宝石755 nm激光治疗太田痣297例,显效率为83.5%,Q开关Nd:YAG1 064 nm激光治疗太田痣340例,显效率为86.76%,显效率没有统计学差异。但Q开关翠绿宝石755 nm激光对褐色太田痣疗效较高:755 nm组褐色显效率为91.62%;1 064 nm组显效率为77.84%,统计学差异有显著性,而Q开关Nd:YAG1 064 nm激光对蓝色太田痣疗效较高:755 nm组蓝色显效率为80.54%;1 064 nm组显效率为92.86%,统计学差异有显著性,且1 064 nm组术后发生色素沉着较755

调Q开关755nm紫翠宝石激光治疗脂溢性角化病65例

目的:观察调Q开关755nm紫翠宝石激光治疗脂溢性角化病的临床效果。方法:对临床65例脂溢性角化病患者采用755nm激光治疗,根据不同临床情况选择不同能量。结果:治疗1次、2次、3次的治愈率分别是46.15%、50.77%、50.77%,有效率分别是59.05%、69.23%、70.77%。治疗次数越多,有效率越高。结论:Q开关755nm紫翠宝石激光治疗脂溢性角化病安全有效。