| 摘要 |
<p>An objective of an endoscope comprising a first lens (L1) with a zero or negative refractive index, a second lens (L2) with a convex face on the image side, and a third lens (L3) with a convex surface on the object side, wherein the following condition is satisfied: 3 < r3F/D3 < 10 where r3F is the radius of curvature of the surface of the third lens on the object side and D3 is the thickness of the third lens.</p> |
