MAGNETIC DISK AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To form an effective landing zone area on a magnetic disk by using a laser beam having a large-sized beam spot advantageous for manufacture. SOLUTION: On the magnetic disk continuous peaks extending from its pedestal surface to the outside are formed by turning a series of effectively overlapping laser radiation onto the landing zone. The effectively overlapping laser radiation is a series of radiation overlapping from 0% to nearly 99% from a regular pulse laser. By forming the continuous peaks, a large-sized laser beam is used, and the depth of focus becomes larger than usual small-sized unoverlapping discrete laser radiation.