Patent ID: 8179618

Claim:
An optical unit, comprising: a first lens; a second lens having a convex shape; a diaphragm; a third lens having a meniscus shape; a fourth lens having a convex shape; and a fifth lens having a negative power, wherein, the first lens, the second lens, the diaphragm, the third lens, the fourth lens, and the fifth lens are arranged in the stated order from an object side to an image plane side, and the fourth lens and the fifth lens satisfy the following conditional expressions (1) and (2), 0.3 ≦f 4 /f≦ 10 (1) −10 ≦f 5 /f≦− 0.3 (2) where f represents a total focal length, f4 represents a focal length of the fourth lens, and f5 represents a focal length of the fifth lens.