PHOTOGRAPHIC LENS OPTICAL SYSTEM

摘要

PURPOSE: A photographic lens optical system is provided to minimize the size of the optical system by applying the lens to the aspherical surface. CONSTITUTION: The first optic(10) has the index of refraction of the positive((+) Power) and the convex surface in the subject(OBJ) and image pickup device(60). The second lens(20) has the index of refraction of the negative((-) Power) and the concave surface in the subject and image device. The third lens(30) has the definition index of refraction and the concave in the subject. The fourth lens(40) has the index of refraction of negative and the curve change point in the subject and image device. The incident side and projection face of the first to the fourth lenses are the aspherical surface. The central part of the incident face has convex shape.