Patent ID: 8873164

Claim:
A lens optical system comprising first, second, third, fourth, and fifth lenses that are arranged between an object and an image sensor where an image of the object is formed, in order from an object side, wherein the first lens has a positive (+) refractive power and an incident surface that is convex toward the object, the second lens has a negative (−) refractive power and a meniscus shape that is convex toward the object, the third lens has a positive (+) refractive power and both convex surfaces, the fourth lens has a positive (+) refractive power and a meniscus shape that is convex toward the image sensor, and the fifth lens has a negative (−) refractive power and an incident surface and an exit surface, at least one of the incident surface and the exit surface is an aspherical surface, wherein a viewing angle θ of the lens optical system and a total length TTL of the lens optical system satisfy the following inequality, 0.5<tan θ/ TTL <1.5.