Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A Study on the Effect of Shrinkage on Lens Deformation in Optical Lens Manufacturing Process Using Thermosetting Resin Material

열경화성 수지 재료를 이용한 광학 렌즈 제조공정에서 렌즈 변형에 대한 수축률이 영향에 관한 연구

  • Park, Si Hwan (School of Mechanical Engineering, Ulsan College)
  • 박시환 (울산과학대학교 기계공학부)
  • Published : 2022.09.30
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Abstract

In order to reduce the manufacturing costs of the glass lens, it is necessary to manufacture a lens using a UV curable resin or a thermosetting resin, which is a curable material, in order to replace a glass lens. In the case of forming a lens using a thermosetting material, it is necessary to form several lenses at once using the wafer-level lens manufacturing technologies due to the long curing time of the material. When a lens is manufactured using a curable material, an error in the shape of the lens due to the shrinkage of the material during the curing process is an important cause of defects. The major factors for these shape errors and deformations are the shrinkage and the change of mechanical properties in the process of changing from a liquid material during curing to a solid state after complete curing. Therefore, it is necessary to understand the curing process of the material and to examine the shrinkage rate and change of physical properties according to the degree cure. In addition, it is necessary to proceed with CAE for lens molding using these and to review problems in lens manufacturing in advance. In this study, the viscoelastic properties of the material were measured during the curing process using a rheometer. Using the results, Rheological investigation of cure kinetics was performed. At the same time, The shrinkage of the material was measured and simple mathematical models were created. And using the results, the molding process of a single lens was analyzed using Comsol, a commercial S/W. In addition, the experiment was conducted to compare and verify the CAE results. As a result, it was confirmed that the shrinkage rate of the material had a great influence on the shape precision of the final product.

Keywords

Acknowledgement

본 논문은 2022년도 소재부품기술개발 소재부품패커지형기술개발사업(산업통상자원부)의 재원으로 한국산업기술평가관리원의 지원을 받아 수행된 연구임(No.20013303, 열가소성 및 열 UV경화형 광학플라스틱 수지의 광학렌즈와 모듈 개발)

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