Japan Science & Technology Agency (JST) has established a technology for low cost mass-production of resin lenses with anti-reflection function jointly with Ito Optical Industrial Co., Ltd. A microstructure of metal nanoparticle is formed on the surface of the die used for injection molding of resin lens, to which anti-reflection function is given. Cost reduction is expected because the process of multi-layer coating that was required for giving this function to lenses in conventional method is no longer necessary. The new technology uses nanoparticle formed under vacuum process as a mask to produce a die with nanoparticle on the surface through etching method. This technology is applicable to lenses of smaller radius of curvature, on which conventional multi-layer coating method was not applicable. The new technology is effective for lenses of compact digital cameras or camera modules of mobile phones, according to JST.

Lithography is used in general to form nm-size microstructure. However, since lithography equipment is expensive, it is unprofitable to use lithography for manufacturing optical lenses. To solve this problem, JST has been working on research and development of technology to manufacture the aforementioned die. The die is manufactured thorough the following procedures. As a first step, mask of nanoparticles is formed on the surface of die under vacuum process. Then, nanostructure is produced on the die surface by dry etching. This nanostructure can be produced both on concave and convex sides. It was confirmed that resin lenses inject-molded using this die have reduced reflection and improved transmission factor.

Sample shipment of the lenses based on this technology is slated for the summer of 2007. JST is also currently working on development of mold press die for glass. This die production technology was jointly developed by Kazuma Kurihara and Takashi Nakano who belong to the Super Lens Technology Research Team at the Center for Applied Near-Field Optics Research of JST. The company has technologies for die production, injection molding, etc. In addition, it cooperates with Tokai Seimitsu Kogyo Co., Ltd. in regard to these technologies.

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