This paper proposes a novel approach that forms image using matrix technique for ray trace,in the condition of axial ray and axial object.

In this paper an introduction to the matrix method for paraxial ray in geometrical optics is presented.

Under paraxial ray conditions, the object-image formula for a single refercating spherical surface is derived from the ray equation, the eikonal equation, vectorial representation of the refractive law, mixed characteristic function and the refractive matrix for spherical surface.

Study on auto-focalizationof the near axle meridian light in square regulation graded index fiber;