Distortion-compensated multifocusing of ultrashort-pulsed laser beams for precision processing

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04112
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18020:Manufacturing and production engineering-related
• Research Institution: Toyo University
• Principal Investigator: Amako Jun 東洋大学, 理工学部, 教授 (20644628)
• Co-Investigator(Kenkyū-buntansha): 中野 秀俊 東洋大学, 理工学部, 教授 (90393793)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 超短パルスレーザー / ビームアレイ / 回折光学 / パルス波形整形 / 分散補償 / 色収差補正

Outline of Final Research Achievements

We have developed a novel optical system that splits an ultrashort-pulsed laser beam with a diffractive beam splitter to make a distortion-compensated pulse beam array in a practically significant length. Diffracted ultrashort pulse beams are distorted in space and time owing to the broad spectra of the pulses. Given that all distortions come from system dispersions, key to the pulse distortion compensation is dispersion management. Using simple formulas we designed the optical system in which hybrid lenses are of essence, which effectively manage material and angular dispersions of the system. Through system evaluations using 20-fs laser pulses, we have corroborated that the designed optical system is able to remove pulse distortions, thereby improving the spatio-temporal focusing resolutions of the system. The proposed pulse delivery technique enables high-throughput, non-thermal ablation of materials, thus contributing to industrial applications of ultrashort laser processing.

Free Research Field

光工学

Academic Significance and Societal Importance of the Research Achievements

本研究成果の学術的意義は、回折ビームスプリッタで超短パルスビームアレイをつくる光学系の設計に関して、時空間のパルス波形歪を除くために不可欠な分散補償の考え方を示し、パルスビームアレイの均一性を議論するために必要な回折効率の定式化を行った点にある。一方で本研究成果の社会的意義は、超短パルスレーザーを用いた加工技術を製造ラインへ広く導入するための具体的な方策を提案し、この加工技術がもたらす製造プロセスにおける技術革新を通して製品の市場競争力の議論を可能にした点にある。