摘要
研制了激光超声测厚传感器 ,并对其测试原理进行了讨论。该传感器具有高频响、频带宽、较高的灵敏度且易于调节。进而采用该传感器测试了由脉冲Nd∶YAG激光在抛光的薄铁片上所激发的超声纵波。根据铁片背面对心处接收到的超声纵波及其回波波形 ,可以推算出样品薄板的厚度。理论和实验测试结果显示 ,该传感器的相对测量误差达 0 .5 %。
A new laser ultrasonic sensor for testing samples’ thickness is developed. The detection principle is discussed in detail. This sensor has high-frequency response,high sensitivity and is easy to adjust. The sensor is used to detect laser-induced ultrasonic longitude-wave at the epicenter of the rear metallic surface when pulse Nd∶YAG laser is focused on polished iron plate.Well-defined longitude-wave and its echo waves are acquired. Based on the experimental results,the sample’s thickness can be deduced.The theoretical and experimental results are in good agreement with relative error of 0.5%.
出处
《激光技术》
CAS
CSCD
北大核心
2003年第6期557-559,共3页
Laser Technology
基金
国家自然科学基金
江苏省自然科学基金
教育部高校优秀青年教师奖励计划
激光技术国家重点实验室开放基金资助项目
关键词
激光超声
光偏转
测厚传感器
纵波
laser ultrasound
optical beam deflection
senor for testing thickness
longitudinal wave
