astigmatic focus वाक्य

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