Distortion-compensated multifocusing of ultrashort pulse beams for nano- and micro-processing

2016 Fiscal Year Final Research Report

• Project/Area Number: 26420059
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Production engineering/Processing studies
• Research Institution: Toyo University
• Principal Investigator: AMAKO JUN 東洋大学, 理工学部, 教授 (20644628)
• Research Collaborator: MURAKAKI Takumi ; UEDA Yoshihito ; SATO Shin ; TAKEDA Shu ; KANNO Takayuki ; KOBAYASHI Masaya
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 超短パルス / ビーム列 / 回折光学 / 光学設計 / 光線行列解析

Outline of Final Research Achievements

We have developed a cascade optical system for multifocusing of ultrashort pulse beams. The system consists of a diffractive subsystem, a refractive subsystem, and a phase plate located between them. The primary reason for pulse distortions is chromatic aberrations arising from a diffractive beam splitter. Two subsystems optically coupled in cascade correct chromatic aberrations and the phase plate compensates for angular dispersions, while remaining material dispersions are removed by pre-chirping the input pulse. We designed a prototype system for evaluation by applying the aberration correction conditions derived from a ray-matrix analysis. The designed system was evaluated with 20-fs pulses by characterizing the transmitted pulses in terms of spatial and temporal profiles to verify the proposed beam delivery scheme. This optical system, which has the potential to be extended to sub-20 fs, enables thermal-free and high-throughput nano-and micro-processing using ultrashort pulses.

Free Research Field

光工学