论文部分内容阅读
本文介绍了一种可利用激光精确测量低的跑道能见度的仪器。该仪器由光学发射与接收系统、信号放大与处理系统及显示系统三部分组成。其中，光学发射与接收系统主要包括：Ｎｄ：ＹＡＧ激光器、倍频器、准直镜、扩束镜、分束镜、接收镜头、截止滤光片、窄带干涉滤光片及ＰＩＮ光电二极管等；信号放大与处理系统主要包括：电压跟随放大电路、可程控可变增益放大电路、计时电路、模———数转换电路及计算机系统等；显示系统则主要由显示器、打印机及接口电路等组成。文中还详细介绍了该仪器对低能见度进行精确测量的理论依据，讨论了其中的技术难点及相应的解决方法。
This article describes an instrument that uses lasers to accurately measure low runway visibility. The instrument consists of optical transmitting and receiving system, signal amplification and processing system and display system composed of three parts. The optical transmitting and receiving system mainly includes Nd: YAG laser, frequency multiplier, collimating lens, beam expander, beam splitter, receiving lens, cut filter, narrowband interference filter and PIN photodiode, Signal amplification and processing systems include: voltage follow the amplifier circuit, programmable variable gain amplifier, timing circuit, analog-digital conversion circuits and computer systems; display system is mainly composed of monitors, printers and interface circuits. The article also introduces the theoretical basis of the instrument for accurate measurement of low visibility and discusses the technical difficulties and the corresponding solutions.