| 摘要 |
PURPOSE:To obtain a plastic lens having high surface accuracy by distributing uniformly the thickness of an acrylic ester resin film formed between a plastic and a reflection preventive film. CONSTITUTION:Dip coating is accomplished by dipping an acrylic lens 4 in, for example, an acrylic ester soln. 1 while positioning downward the side (a) of said lens in such a way that the angle theta between the lens surface and the liquid surface attains max. 20 deg., and pulling up the lens in the arrow (p) direction perpendicular to the lens surface at a pulling rate of 20mm./min. The lens 4 is thereafter subjected to 2-3sec of UV irradiation with a high pressure mercury vapor lamp of 80W/cm apart at 10cm therefrom to cure half the acrylic ester resin film on the surface of the lens 4 into the state of not completely curing the same. The lens 4 is then turned upside down to bring downward the side (b) and the lens 4 is subjected to dipping and pulling up under the same condition as mentioned above. The acrylic ester resin film coated on the lens is completely cured at >=0.5mm. thickness by extending the time for the UV irradiation to ten seconds. The film thickness distribution in this case is made max. <2 times. |
