时间监控双离子束溅射沉积制备荧光滤光片

文章对中心波长为488nm、520nm、560nm和600nm的专用滤光片进行了研制,为保证通带高透过率的要求和对背景光的高效抑制,采用单基片进行膜系叠加的方法进行了组合带通滤光片的设计,并采用时间监控膜厚的双离子束溅射沉积薄膜技术进行了镀制,成功的制备出供生化仪使用的一系列荧光栅滤光片。     

6.5W LD泵浦914 nm钒酸钇激光器

掺钕钒酸钇作为一种重要的激光增益介质,以其受激发射截面大、对809 nm波长存在很强的宽吸收带、偏振发射等优点,在LD端面泵浦全固态激光器中得到了广泛的应用,其中比较有应用价值的受激发射谱线为1 064 nm,1 342 nm和914 nm。由于914 nm谱线属准三能级结构,以及钒酸钇晶体较低的热导率,限制了其向大功率方向的发展。研究了一种具有较高效率的大功率钒酸钇连续输出激光器,通过采用简单的折叠腔设计和对腔镜镀适当的介质膜,抑制了波长为1 064 nm和1 342 nm的高增益谱线。当泵浦功率为29W时,输出功率高达6.5W,斜效率为37.9%,光光转换效率为22.4%.     

LD 泵浦腔内和频连续589nm 黄光激光器

在理论上分析和计算了Nd∶YAG激光器双波长同时运转时输出镜的透过率,提出在双波长共同运转的前提下适当减小输出镜对增益较大谱线的透过率,可以获得更高的腔内和频效率,并从实验上加以证实。实验中利用2W 激光二极管端面泵浦Nd∶YAG 的方式,得到1064nm和1319nm 连续的双波长运转,在优化输出镜透过率以后,在腔内加入Ⅰ类临界相位匹配切割的LBO 和频晶体得到20mW的589nm 黄光输出。     

Nd:YAG人眼安全波段1 444 nm激光器光学薄膜的研制

从激光晶体低增益谱线的运转机理出发,研制了对LD泵浦Nd：YAG实现人眼安全波段1444nm激光器所使用的光学薄膜。为保证1444nm激光的高效振荡,对Nd：YAG晶体的其它发射谱线946nm、1064nm、1319nm和1338nm进行有效抑制,对膜系要求进行了深入分析。将光谱特性要求合理分配在谐振腔的2个端镜上,从整体上考虑谐振腔对各谱线的透射／反射率要求,采用传统的解析设计同计算机膜系自动优化设计相结合的方法对膜系进行了优化计算,设计出符合要求并具有好的容差特性的膜系。采用离子反应溅射沉积法成功制备出1444nm激光器所使用的全介质激光反射膜,实现了人眼安全波段1444nm激光的高效振荡。在注入泵浦功率为1.5w的条件下,获得268mW的稳定TEM00模线偏振激光输出,斜效率达24．3％,M^2因子小于1．3。     

Design and fabrication of a novel high damage threshold HfO2/TiO2/SiO2 multilayer laser mirror

This paper describes a new method to design a laser mirror with high reflectivity, wide reflection bandwidth and high laser-induced damage threshold. The mirror is constructed by three materials of HfO2/TiO2/SiO2 based on electric field and temperature field distribution characteristics of all-dielectric laser high reflector. TiO2/SiO2 stacks act as the high reflector (HR) and broaden the reflection bandwidth, while HfO2/SiO2 stacks are used for increasing the laser resistance. The HfO2/TiO2/SiO2 laser mirror with 34 layers is fabricated by a novel remote plasma sputtering deposition. The damage threshold of zero damage probability for the new mirror is up to 39.6 J/cm2 (1064 nm, 12 ns). The possible laser damage mechanism of the mirror is discussed.     

Design of large acceptance angle polarizing beam splitter for laser-based displays

The performance of broadband polarizing beam splitters(PBSs) is sensitive to the incident angle.By taking account of the spectrum of the laser source and using the needle optimization method,a large acceptance angle PBS for laser-based displays is designed.The average degrees of polarization in transmission and reflection can reach 0.989 and 0.980 for an acceptance angle of 13.6?in air using two materials,while better results of 0.993 and 0.989 for an acceptance angle of 14.8?in air are attained when three ...     

High damage threshold HfO2/SiO2 multilayer mirrors deposited by novel remote plasma sputtering

Sputtering deposition coatings offer significant advantages on electron beam (EB) deposition, including high packing density, environmental stability and extremely low losses. But the inherent high compressive stress affects its application in high power laser system. This paper describes the technical feasibility of high damage threshold laser mirrors deposited by a novel remote plasma sputtering technique. This technique is based on generating intensive plasma remotely from the target and then magnetically steering the plasma to the target to realize the full uniform sputtering. The pseudo-independence between target voltage and target current provides us very flexible parameters tuning, especially for the films stress control. Deposition conditions are optimized to yield fully oxidized and low compressive stress single layer HfO2 and SiO2. The high damage threshold of 43.8 J/cm2 for HfO2/ SiO2 laser mirrors at 1064 nm is obtained. For the first time the remote plasma sputtering is successfully applied in depositing laser mirrors with high performance.     

Novel metal-dielectric metameric optical filters for optical security devices

Optical security devices play an essential role in the fight against counterfeiting. In this paper, we study and design a pair of metal-dielectric optical filters based on metameric effect, which offer a hidden image effect by the color shift at a specific angle of observation. Compared with all-dielectric multilayer system, the metal-dielectric multilayer structure has larger color shift with varying incident angle, higher color saturation and fewer layers. Finally, the stacks with 5 layers and 7 layers are achieved, and the color difference index is only 0.71, which shows good metameric matching effect. Simultaneously, the sensitivity of filters to deposition errors is analyzed when the thickness deviation is ±2%, and the results show that the two filters have good manufacturability.     

1.1μm波段Nd:YAG激光运转及其腔内倍频

为了提高Nd：YAG／LBO腔内倍频黄光激光器输出功率的稳定性,通过在腔内插入FP标准具选择出单-激光谱线来实现,同时通过FP标准具的角度调谐还得到了1．1μm波段3条分离谱线的单独倍频运转。用2WLD抽运Nd：YAG,腔内加入150μm厚的熔石英FP标准具,先通过F—P标准具放置角度的调节获得单一谱线的基频光运转,再通过LBO腔内倍频获得高稳定性的黄光输出,在1．6W的抽运功率下,556nm、558nm和561nm的输出功率分别为85mW、65mW和71mW,光光转换效率分别为5．31％、4．06％和4．68％。     

Magnetic interference gonioapparent thin film based on metal-dielectric-metal structure for optical security devices

In recent years, magnetic interference thin films have gained wide attention in optical security devices field by virtue of their gonioapparent and dynamic 3D effects. Based on the color mechanism of metal-dielectric Fabry-Perot structure, a novel seven-layer magnetic thin film structure is proposed by adopting the ultrathin metal layer as a bonding layer and a pure metallic Ni layer as a magnetic layer as well as a reflective layer. Color target optimization optimac method is utilized that realizes the seven-layer metal-dielectric optically variable magnetic thin film structure with green at the normal incidence and purple-red at 60°. The structure effectively solves the delaminate problem and simplifies the multilayer structure. Through different combined magnetic field designs, the magnetic orientation experiment of the prepared magnetic optically variable thin film is carried out, and the 3 D anti-counterfeiting with remarkable dynamic color change effect is obtained, which provides a new solution for optical security devices.