| 摘要 |
PROBLEM TO BE SOLVED: To inexpensively provide a lens suitable for a recognition camera of a packaging equipment. SOLUTION: In the order from the object side to an image surface side, the followings are successively arranged, i.e., a first biconvex shaped lens 1 having positive refractive power, a second flat and convex shaped lens 2 in which its convex surface is faced toward the object side and positive refractive power is provided, a third biconvex shaped lens 3 having positive refractive power, a fourth biconcave shaped lens 4 which is joined to the third lens 3 and has negative refractive power, an aperture diaphragm 9, a fifth biconcave shaped lens 5 having negative refractive power, a sixth biconvex shaped lens 6 which is joined to the fifth lens 5 and has positive refractive power, a seventh biconvex shaped lens 7 having positive refractive power and an eighth meniscus shaped lens 8 which has a convex surface directed toward the object side and has positive refractive power. Thus, the lens, which is inexpensive as a whole and having a telecentric characteristic toward the object side, is provided. COPYRIGHT: (C)2006,JPO&NCIPI
|
