[ Papers ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 30, No. 3, pp.203-211

ISSN: 2508-5107 (Online)

Print publication date 15 Jun 2021

Received 06 Apr 2021 Revised 04 May 2021 Accepted 06 May 2021

DOI: https://doi.org/10.7735/ksmte.2021.30.3.203

래스터 밀링을 이용한 마이크로렌즈 어레이 금형 가공

김영복^a^{, b} ; 이의삼^a ; 한승헌^a ; 이동길^a ; 이준기^b^{, *}

Mold Machining of Microlens Array Using the Raster Milling Method

Young Bok Kim^a^{, b} ; Wee Sam Lee^a ; Seung Heon Han^a ; Dong Kil Lee^a ; June Key Lee^b^{, *}

aIntelligent Optical Module Research Center, Korea Photonics Technology Institute
bDepartment of Materials Science & Engineering, Chonnam National University

Correspondence to: ^*Tel.: +82-62-530-0308 E-mail address: junekey@jnu.ac.kr (June Key Lee)

Abstract

Machining experiments were conducted to improve the surface morphology of a microlens array using the raster milling method. Three types of raster milling methods were investigated in this study: parallel, tilted, and single-point raster milling. Further, the characteristics of the machined surfaces were analyzed. In parallel raster milling, hump formation on the machined surface was promoted by the tool’s run-out deviation. In tilted raster milling, tool marks occurred on the machined surfaces owing to tool wear. In single-point raster milling, wherein the tool axis rotated according to the lens curvature during machining, the form accuracy of peak-to-valley was confirmed to improve from 0.46 to 0.07 μm. Therefore, single-point raster milling was validated as a highly robust machining method because the surface morphology was rarely affected by tool errors.

Keywords:

Micro lens array, Raster milling, Ultra precision diamond machine, Diamond ball endmill, Surface roughness, Optical lens

Acknowledgments

이 연구는 산업통상자원부 및 산업기술평가관리원(KEIT)의 연구비 지원에 의한 연구임(고온성형용 GMP 장비 및 제조기술 개발, 20010775).

이 논문은 전남대학교 학술연구비(과제번호: 2021-1446)의 지원에 의하여 연구되었음.

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Young Bok Kim

Researcher in the Intelligent Optical Module Research Center, Korea Photonics Technology Institute.His research interest is ultra-precision machining.

E-mail: ybkim@kopti.re.kr

Wee Sam Lee

Researcher in the Intelligent Optical Module Research Center, Korea Photonics Technology Institute.His research interest is optical lens design.

E-mail: wslee@kopti.re.kr

Seung Heon Han

Researcher in the Intelligent Optical Module Research Center, Korea Photonics Technology Institute.His research interest is camera module system.

E-mail: shawnhan@kopti.re.kr

Dong Kil Lee

Researcher in the Intelligent Optical Module Research Center, Korea Photonics Technology Institute.His research interest is the fabrication of optical lenses.

E-mail: dklee@kopti.re.kr

June Key Lee

Professor in the Department of Materials & Engineering, Chonnam National University.His research interest includes Material and Engineering.

E-mail: junekey@jnu.ac.kr