Characteristics of the depth of focus in a high-NA optical system with a SIAX for data storage

We study the tolerance characteristic of SIAX and suggest a newly designed SIL-Axicon system for the better tolerances. Methods for checking beam quality, optimization and remaining problems are suggested. SIL-Axicon system shows more tolerances in the uniformity of beam incident angle. Bessel beam (BB) with SIL can be used for multi layer high density data storage systems. We study the tolerance characteristic of SIAX and suggest a newly designed SIL-Axicon system for the better tolerances.