本文论述了研制成的一种用于计算机硬盘盘片等超精密表面粗糙度非接触测量的智能化仪器;提出了基于外差干涉原理的平行双光束设计方案,简述了该测量仪结构、光学系统、驱动控制系统、光电转换系统、数据处理系统及精密定位系统;给出了表面粗糙度多刻线标准样板以及磁盘表面粗糙度的实测曲线.测试结果表明,该测量仪的示值误差优于3%,示值变动性小于±3%,可实现自动调焦自动测量. In this paper, an intelligent instrument developed for non-contact measurement of ultra-precision surface roughness such as computer hard disk platters is presented. A parallel dual-beam design scheme based on heterodyne interference principle is proposed. The structure, Optical system, drive control system, photoelectric conversion system, data processing system and precision positioning system. The measured curves of the surface roughness multi-scale standard sample and the disk surface roughness are given. The test results show that the measuring instrument’s indication error Better than 3%, showing less than ± 3% change in value, automatic measurement can be achieved automatically.