| 摘要 |
According to one embodiment of the present invention, an imaging optical system, in order from an object side, comprises: a first lens having negative a refractive power; a second lens having a refractive power; a third lens having a refractive power; a fourth lens having a refractive power; and a fifth lens of which an upper surface is concave in an area of a radical axis, having a positive refractive power. The lenses are arranged to increase improvement of aberration and realize the imaging optical system with a wide viewing angle and high-resolution. Moreover, the image is able to be much brighter by the imaging optical system. |
