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http://dx.doi.org/10.7736/KSPE.2014.31.7.561

Mold Technology for Precision Injection Lens  

Ha, Tae Ho (Department of Ultra Precision Machines & Systems, Korea Institute of Machinery & Materials)
Jo, Hyoung Han (N2A. Ltd.)
Song, Jun Yeob (Department of Ultra Precision Machines & Systems, Korea Institute of Machinery & Materials)
Jeon, Jong (N2A. Ltd.)
Publication Information
Journal of the Korean Society for Precision Engineering / v.31, no.7, 2014 , pp. 561-567 More about this Journal
Abstract
Precision injection mold is an essential element in order to manufacture small and precision plastic lenses used for phone camera. There are many critical factors to meet the requested specifications of high quality plastic lenses. One of the main issues to realize high quality is minimizing decenter value, which becomes more critical as pixel numbers increases. This study suggests the method to minimize decenter value by modifying ejecting structure of the mold. Decenter value of injection-molded lens decreased to 1 ${\mu}m$ level from 5 ${\mu}m$ by applying suggested ejecting method. Also, we also developed BIS (Built-in Sensor) based smart mold system, which has pressure and temperature sensors inside of the mold. Pressure and temperature profiles from cavities are obtained and can be used for deduction of optimal injection molding condition, filling imbalance evaluation, status monitoring of injection molding and prediction of lens quality.
Keywords
Plastic Lens; Injection Mold; Decenter; Built-in Sensor;
Citations & Related Records
Times Cited By KSCI : 5  (Citation Analysis)
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