| 摘要 |
The present invention relates to a lens system and an optical device with the same and, more specifically, relates to a lens system including a first lens group having a negative reflective power from an object side to an image side along an optical axis, an aperture, and a second lens group with positive reflective power capable of maintaining excellent optical performance by satisfying equation 1 and equation 2 and reducing a size and weight of the entire lens system, and to an optical device with the lens system. [Equation 1] 1.0 < (C1 + C9) / F < 2.0 (C1 is a lens size in the object side of a first lens, C9 is a lens size of the image size of a ninth lens, and F is a focal distance of the entire lens system in a telephotographic state). [Equation 2] 0.6 < fF / fR < 0.9 (fF is a distance between the first lens group to the aperture, fR is a distance between the aperture and the second lens group). |
