摘要 |
<P>PROBLEM TO BE SOLVED: To mitigate deterioration of optical performance with respect to birefringence specific to resin lenses and unevenness of refraction factor while improving the optical performance by using the resin lens, and to reduce occurrences of ghost light due to lens surfaces of the resin lenses. <P>SOLUTION: In an optical system having a plurality of lens groups, a final lens group arranged closest to an image side among the plurality of lens groups has a resin lens with a concave face toward the image plane side and formed of a resin material, and one or more glass lenses formed of a glass material arranged at an image plane side of the resin lens. A radius of curvature Rp2 of the image plane side lens surface of the resin lens, a radius of curvature Rr1 of the object side lens surface of the first glass lens adjacent to the image side of the resin lens, a distance dp between the resin lens and the glass lens, a focal distance fp of the resin lens, and a composite focal distance fr of the resin lens and the first glass lens are respectively appropriately established. <P>COPYRIGHT: (C)2013,JPO&INPIT |