基于复合晶体的全固态高功率1064nm激光器的实验研究

研究了最大输出功率超过500W的全固态连续高功率1064nm激光器。为了改善热效应,选用了扩散键合方法制成的复合Nd：YAG,有效地降低了高功率激光器中的激光晶体热透镜问题。在实验中,1064nm输出镜的透过率分别为T=10％、30％、35％和40％,得到了512W 1064nm输出,光-光转换效率达到32％。     

TDLAS检测系统的激光器驱动电路

针对温度变化对半导体激光器(LD)的输出激光波长及其工作稳定性的影响,提出运用热电制冷器TEC构成二级制冷系统,分别对激光器的外部和内部温度进行精准控制。采用闭环PID电路产生控制信号控制TEC的驱动电流和方向,从而达到制冷和加热的目的;为进一步实现对驱动信号的滤波,提出采用级联方式的LTC1064构成四阶滤波系统。测试结果表明:TEC温控系统取得了很好的温控效果,响应速度快,精度达到±0.01℃,滤波系统有效滤除了正弦波中的直流分量和高次谐波的干扰,满足激光器对温度和驱动信号的要求。     

双波长585nm/1064nm Nd:YAG激光治疗面部皱纹的效果与安全性

为观察双波长585nm/〖J P 〗1064 nm Nd:YAG激光治疗面部皱纹的疗效与安全性,对42例面部皱纹女性患者采用 双波长585nm/1064nm Nd:YAG 激光 治疗,每4周治疗1次,共5次。通过医师主观评价和VISIA皮肤分析仪对有效性和安全性进行 综合评定。结果表明, 治疗后,所有病例均有改善,临床有效率为92.86％,患者面部皱纹 及毛孔的VISIA值明 显下降,与治疗前相比,差异有统计学意义(P＜0.001)。这表明,Nd:YAG激光用于 面部皱纹的治疗疗效显著,安全性 高。     

585nm脉冲染料/1064nm Nd：YAG复合激光治疗痤疮的疗效观察

目的：观察585nm脉冲染料/1064nmNd：YAG复合激光治疗痤疮的疗效及安全性。方法：应用585nm脉冲染料/1064nm Nd：YAG复合激光对丘疹脓疱性痤疮患者35例以及红斑性痤疮患者26例进行治疗。每4周治疗1次,一共治疗3次。脉冲染料的能量为6.5J/cm2至9J/cm2、1064nmNd：YAG激光为30J/cm2至60J/cm2前者脉宽为0.5ms,后者为15ms：光斑大小均为7mm。丘疹脓疱性痤疮对照组35例外用0.025%维甲酸霜,每晚1次;1%克林霉素磷酸酯凝胶涂抹患处,每天早晨1次;同时口服盐酸米诺环素胶囊0.1g Q12H。结果：治疗的第4周、8周、12周,丘疹脓疱性痤疮患者激光组的平均疗效指数分别为49.83%、75.49%、80.83%,平均Leeds评分分别为0.88、0.69、0.29;红斑性痤疮患者平均疗效指数分别为32.66%、62.14%、83.31%。12周后,丘疹脓疱性痤疮和红斑性痤疮患者激光组的有效率分别为97.14%、88.57%。绝大多数激光治疗者皮肤弹性得到不同程度改善,皮脂分泌有所减少。所有激光治疗者均出现轻微的红斑,但均在24小时内消退;31例患者出现紫癜,一般1-2周内消退不留痕迹;2例患者出现暂时性水疱,未见其他副反应。结论：585nm脉冲染料/1064nmNd：YAG复合激光治疗丘疹脓疱性痤疮及红斑性痤疮有效且副作用小。     

大口径1064nm窄带滤光片的研制

采用现代光通信DWDM镀膜技术,选用Ta2O5/SiO2氧化物硬质薄膜材料,研制成功大口径、高性能1064nm窄带滤光片。给出了从膜系设计到试生产及膜层的性能方面的一些实验结果,表明产品的各项性能指标达到或超过了客户的要求,现已定型批量生产。     

Picosecond pulsed two-photon imaging with repetition rates of 200 and 400 MHz

We show the viability of high-resolution two-photon fluorescence imaging of fixed and live cells by exciting the fluorophores with a train of near-infrared pulses with duration in the picosecond range. This is exemplified with a compact, diode-pumped Nd:YVO₄ laser, emitting trains of 7-ps pulses at a wavelength of 1064 nm, with a repetition rate of 200 MHz at two separate outputs. Incoherent combination of the outputs enabled two-photon excitation with a repetition rate of 400 MHz. For a numerical aperture of 1.4 (oil), we used an average illumination power of up to 20–40 mW at the sample. The pulses were coupled into a beam scanning microscope, either directly or through a single mode glass fibre. Compared with standard femtosecond titanium–sapphire excitation conditions, our experiments were performed with a 2.5 or 5 times higher repetition rate, 30–70 times longer pulses and 10–35 times lower pulse peak intensity. The experiments indicate the possibility of significantly relaxing the temporal pulse width constraints for a series of applications.     

A 1480/1064 nm dual wavelength photo-thermal etching system for non-contact three-dimensional microstructure generation into agar microculture chip

We have developed a new type of non-contact three-dimensional photo-thermal etching method for agar microculture chips exploiting the characteristics of two different wavelengths of infrared laser beams. We used two different wavelengths of infrared (1480 and 1064 nm) focused laser beam as a heat source to melt and remove a portion of 200 μm high agar gel layer on the 5 nm thick chromium-coated glass slide. As the 1480 nm infrared beam is absorbed by water, the agar gel on the light pathway is heated and melted. On the other hand, as the 1064 nm infrared beam is not absorbed by water and agar, the melting of the agar occurred just near the chromium thin layer that absorbs 1064 nm infrared light. Using this non-contact etching, we can easily make microstructures in agar-layer using infrared laser beam only within a few minutes; i.e. cell-culture holes are melted by 100 mW, 1480 nm laser and tunnels by 100 μm/s, 40 mW, 1064 nm laser, respectively. The size of holes and tunnels were also controlled by choosing the irradiation power and time of infrared lasers. Those results indicate that we can make and use microstructures for biological use without any expensive microfablication facilities nor a series of complicated procedure and time.     

I~2C总线在大幅面高速彩色喷绘机中的应用

介绍了I2C总线的结构、工作原理和数据传输方式,详细讨论了基于I2C总线的大幅面高速彩色喷绘机软硬件设计。经研究测试,系统能够喷绘出高精度彩色图像,达到了预期要求。     

1064 nm波段白天背景噪声分析及应用研究

卫星激光测距(SLR)是目前卫星单点距离测量精度最高的技术,已成为高精度测量领域不可或缺的手段。国际上大多数SLR台站采用532 nm的工作波长,在白天测距中存在天空背景噪声大、有效回波识别困难等问题,影响了台站的白天测距数据产出。鉴于白天1064 nm 波段天空背景亮度低,理论上对比分析计算了1064 nm波段与532 nm波段的系统噪声强度。并在晴好白天开展了1064 nm波段的噪声测量,并与532 nm波段的测距系统噪声进行了比较,数据结果与理论分析基本一致。在此基础上,开展了晨昏时段的1064 nm卫星激光测距实验,并获得了多圈次卫星的有效回波数据,为1064 nm的白天卫星激光测距打下了技术基础。     

1064nm激光大气透过率数据库的建立与应用

利用FASCODE计算出1064nm激光的大气透过率,建成透过率数据库,该数据库对应的大气模型为中纬度夏季,斜程范围为(0～10)kin(间隔0.1km),仰角范围为0°～90°(间隔5°),地面能见度范围为(5～20)km(间隔1km),数据库可以根据需要进行扩展.通过对透过率数据曲线进行分析,发现有极少数的数据点不合常理,即随距离增加透过率也略微增加,这是FASCODE软件的Bug.为此,编写了数据修正程序,利用人工介入方法剔除不合常理的数据点;并采用三次c样条插值的方法,补充被剔除的数据点.修正后的数据库,便于在相关软件的迭代计算中调用,如用于激光制导武器作战训练、光电对抗仿真等课题的研究.