| 摘要 |
PROBLEM TO BE SOLVED: To provide a camera head using a compact optical system which is tele-centric in order to prevent a decrease in an amount of peripheral light due to the incident angle characteristic of a CCD and the aberrations of which are sufficiently corrected. SOLUTION: In the camera head having a photographic lens 6 that is attached to the eye-piece section of an endoscope, the photographic lens 6 includes at least a meniscus lens whose convex face is disposed in the direction of the object side, and comprises, in order from the object side, a first lens L1 having a positive refracting power, a second lens L2 having a negative refracting power, a third lens L3 having a positive refracting power, and a fourth lens L4 having a positive refracting power. A condition (1) 1.1<L/f<1.4 for defining the entire length of the optical system of the photographic lens 6 and a condition (2) 0.55<f<SB>1</SB>/f<0.85 for defining the power of the first lens L1, are satisfied. COPYRIGHT: (C)2006,JPO&NCIPI
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