keep the distance meaning in English

患病者保持距离

A sil flying head is designed to keep the distance between sil and recording medium in near - field range . a sil optical data storage system is built up when the recording head is combined with sil flying head . meanwhile , using astigmatic focusing error detection technology and twin optical pick - up heads , a novel nontouching nanometer measurement method is developed to measure the flying height of sil , and provides us with a powerful tool to optimize the design of sil fly head
在sil存储技术研究方面，首先提出一种光学玻璃热熔加工制作sil的新方法，该方法克服了小半径球透镜加工的难题，成功制作出了半球固体浸没透镜；设计了sil飞行头系统，并利用光学头像散法聚焦误差检测原理，设计出一种双光学头sil飞行高度测量方案，实现了sil飞行头飞行高度的测量。