封离式CO2激光器的新应用领域

众所周知,低功率射频(RF)激励封离式CO2激光器可用于塑料切割、橡胶雕刻、木材打标及许多其他有机材料的加工,但却很少有人知道这些激光器还可用于金属的打标和焊接、玻璃打标及在镀铜的印刷线路板上打孔.它能取代价格昂贵的激光器或其他不同的技术,其用途的扩展在很大程度上应归功于改进的加工工艺和新型激光器的设计.     

CO2激光技术在工艺上的飞跃

CO2激光器主要在金属加工工业上用作切割与焊接工具。当人们观察这种气体激光器从科学试验室到作为标准机床和专用机床的工具这一发展过程时，就会认识到在提高坚固耐用的同时，提高功率是始终如一的发展趋向。如同各种工具的发展一样，提高可靠性和耐用性，降低保养花费是很重要的。     

几种CO2激光切雕机光开关的设计与研究

设计与研究了几种用于CO2激光切雕机的光开关,并对其性能进行了讨论和比较。     

降低CO2激光器电源着火电压的方法

本文通过分析和试验，介绍了一种CO2激光器外触发起辉装置，以达到降低CO2激光电源体积和成本的目的。     

大功率扩散冷却型Slab CO2激光器光束质量的研究

本文对国际上最新的大功率扩散冷却型Slab CO2激光器的光束质量进行了全面的测量与实验研究.从原始激光束的光束质量、通过导光系统后激光束质量、聚焦光斑的质量以及焦点漂移四个方面全面考察了Slab CO2激光器的光束质量以及光束的传输、聚焦特性.结果表明,Slab CO2激光器具有高光束质量,其M2因子非常接近1的理想值;激光束具有良好的传输和聚焦性能,可以长距离传输;使用焦距为300mm的聚焦镜聚焦,聚焦光斑的束腰半径约为134μm,光束横截面能量分布接近理想的高斯分布,焦深约为5mm,在加工范围内(3m),激光束的焦点漂移量大约为1mm.另外,采用Slab CO2激光器对厚度为10mm的低碳钢在不同的离焦位置进行激光深熔焊接实验,讨论了激光光束质量和焦深对焊接结果的影响.     

二氧化碳激光的临床应用

我所与南通医学院附属医院合作，于1977年11月～1981年6月，在动物实验的基础上，用CO2激光治疗301例，取得了较好的效果，现小结如下：     

不断发展的CO2激光器

世界上第1台商用CO2激光器采用了一种很大的气体流动系统，需要定期维修和保养，而今天，CO2激光器已取得惊人的进展，人类正计划将一种体积小、重量轻并能连续工作5年的CO2激光器系统送往太空。     

A new design for rf-excited CO2 lasers

In this paper a new ‘four-pole’ electrode design for radiofrequency excited CO₂ lasers is described. Here, the two functions of the discharge tube, rf-excitation and dischare cooling can be optimized separataly. With a symmetric rf excitation technique electromagnstic interference is also minimized. A prototype laser with 50 cm cavity length produced about 2.5 W laser output power at 5% efficiency.     

Improved excitation techniques for atmospheric pressure CO2 lasers

A simple and rugged electrode structure is described for the production of uniform pulse-excited discharges throughout large volumes at atmospheric pressure. Output energy densities of 18 mJ/cm3 have been achieved in a multimode CO2 laser. The performance is compared with that of a novel mesh-cathode electrode system.     

New FIR lasers from CO2 laser-excited 1,1-difluoroethene

Forty two new far-infrared laser lines have been obtained from CH₂CF₂ by pumping with a 60 W CO₂ laser. Several of these emissions have been assigned to rotation transitions within the v4 and v9 vibration manifolds; hot and combination band transitions are suspected for the others.     

Numerical investigation on machining glass with CO2lasers

When a glass substrate was irradiated by three different temporal shapes of laser sources, namely, linetime-shape laser, triangle-time-shape laser, and parabolatime-shape laser, the mathematical models were proposed,and the temperature distribution and the resulting thermal stress were calculated by the finite-element-method (FEM)software ANSYS.With these three types of lasers having the same output laser energy, the resulting thermal stress induced in the glass substrate was analyzed.The results showed that, with the same output laser energy, the thermal stress produced in glass heated by line-time-shape laser is higher than that produced in glass heated by the other two shapes of lasers.     

Quantum dots keep their distance

Probes developed by a team of researchers at Sandia Laboratories have enabled real-time observation of the formation of quantum dots, revealing that the dots repel each other. Quantifying the repulsion may help in turning assemblages of quantum dots into future solid-state lasers.     

激光多普勒双光束横向测速技术研究

为了实现基于CWCO2激光的运动目标横向速度测量,使用双光束方式在室内进行了实验,得到了较清晰的多普勒频移信号,并对信号数据进行了滤波处理,以提高信噪比。计算出了运动目标速度并与实际速度进行了比较。结果表明,测得速度值与实际值相当接近。