Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Study on Ultra Precision Grinding of Silicon Carbide Molding Core for High Pixel Camera Phone Module

고화소 카메라폰 모듈을 위한 Glass 렌즈 성형용 Silicon Carbide 코어의 초정밀 가공에 관한 연구

  • Kim, Hyun-Uk (Materials Fabrication Laboratory, The Institute of Physical and Chemical Research (RIKEN)) ;
  • Kim, Jeong-Ho (Korea Photonics Technology Institute, Ultra Precision Optics Team) ;
  • Ohmori, Hitoshi (Materials Fabrication Laboratory, The Institute of Physical and Chemical Research (RIKEN)) ;
  • Kwak, Tae-Soo (Department of Mechanical Engineering, Jinju National University) ;
  • Jeong, Shang-Hwa (Department of Mechanical Engineering, Chosun University)
  • Received : 2009.06.22
  • Accepted : 2010.05.13
  • Published : 2010.07.01
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Abstract

Recently, aspheric glass lens molding core is fabricated with tungsten carbide(WC). If molding core is fabricated with silicon carbide(SiC), SiC coating process, which must be carried out before the Diamond-Like Carbon(DLC) coating can be eliminated and thus, manufacturing time and cost can be reduced. Diamond Like Carbon(DLC) is being researched in various fields because of its high hardness, high elasticity, high durability, and chemical stability and is used extensively in several industrial fields. Especially, the DLC coating of the molding core surface used in the fabrication of a glass lens is an important technical field, which affects the improvement of the demolding performance between the lens and molding core during the molding process and the molding core lifetime. Because SiC is a material of high hardness and high brittleness, it can crack or chip during grinding. It is, however, widely used in many fields because of its superior mechanical properties. In this paper, the grinding condition for silicon carbide(SiC) was developed under the grinding condition of tungsten carbide. A silicon carbide molding core was fabricated under this grinding condition. The measurement results of the SiC molding core were as follows: PV of 0.155 ${\mu}m$(apheric surface) and 0.094 ${\mu}m$(plane surface), Ra of 5.3 nm(aspheric surface) and 5.5 nm(plane surface).

Keywords

References

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