Computer simulation method using highprecision form representatioin method including mid-spatial frequency

Research Project

Project/Area Number	16K06022
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	Tokyo Denki University
Principal Investigator	MORITA Shinya 東京電機大学, 工学部, 教授 (30360655)
Project Period (FY)	2016-04-01 – 2019-03-31
Project Status	Completed (Fiscal Year 2018)
Budget Amount *help	¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000) Fiscal Year 2018: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000) Fiscal Year 2017: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000) Fiscal Year 2016: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Keywords	中間周波数形状 / 輪帯ボケ / 長田パッチ / 光学素子 / 微小工具研磨 / 金型 / 修正研磨 / 非球面 / ボケ像 / 光学シミュレーション / 超精密加工 / 光線追跡 / 高精度形状モデル / 自由曲面光学素子 / 超精密モデリング / 中間周波数
Outline of Final Research Achievements	It became possible to simulate the optical performance in the molding process of aspheric optics for digital single lens cameras, and to design the polishing path to obtain a lens shape with less ring band blurring. (1) The optimal conditions to model curved surfaces with sub-micron fluctuation in mid-spatial frequency wavelength created by ultraprecision machining process were clarified by this study.(2) The removal characteristics of the optical mold surface shape with sub-micron fluctuation in mid-spatial frequency wavelength by ultrasonic-assisted small tool polishing were clarified. (3) We examined ray tracing method using Nagata patch to simulate ring band blurring, and it was possible to quantitatively evaluate the ununiformed intensity of light in low calculation cost.
Academic Significance and Societal Importance of the Research Achievements	カメラ用の非球面レンズや自動車ヘッドライト用の自由曲面光学素子の加工技術において，中間周波数形状と呼ばれる波長数10μm～数百μmの表面微小うねりによる光学機能の悪化が問題となる．この領域は砥粒のランダムネスによる平均化効果が十分に働かない領域であるために研磨工程で十分に除去することが難しい．また十分に除去しようと長時間の研磨と行うと，加工時間コストの増大と大域的な形状精度の悪化が問題となる．そこでによる中間周波数形状の高精度かつ高速演算が可能な光線追跡手法を開発し，最小限の加工時間で十分な光学性能を持つコンピュータシミュレーション技術を開発した．