DRNI型磁盘表面粗糙度非接触测量仪

Disk Surface Roughness A Non-Contact Instrument

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.

The principle, structure, optical system design, driving control system, electro-optical transformation, information processing system and precision positioning system of an intelligent instrument for non-contact measurement of computer hard disk surface roughness are described. It is based on the principle of heterodyne interferometry. The surface to be examined is illuminated by two beams with parallel optical axis and of different diameters and different frequencies. Errors due to mechanism movement and random deflection can be compensated. The lateral resolution is less than 2 um and the height resolution is 1 nm. The actual profile curves of the standard surface roughness sample and disk surface are given. It is shown that the indication error 'of the instrument is less than 3% and the indication variation is in a range of ±3%.