| 摘要 |
An optical system comprises, in order from the object side, a first lens having a biconvex shape and having a positive refractive power, a second lens having a meniscus shape with a concave surface facing the object side and having a negative refractive power, a third lens having a negative refractive power, a fourth lens having a meniscus shape with a concave surface facing the object side and having a positive refractive power, and a fifth lens having a negative refractive power. The first lens and the second lens are cemented together. |
