Photo-polymer objective lens for red blue lasers

The authors designed a photo-polymer objective lens which can be used for b oth red and blue lasers. The following two conditions were set to facilitat e this lens production process. 1) We chose photo-polymer resin as one of the doublet lens materials. 2) One surface of the photo-polymer lens was designed to he Aat. We installed this lens in pickup heads and played back some disks. Its perf ormance was almost as good as that of a noncompatible glass lens.