At present the cell array lens is usually cylinder or hemispheroid whose fill-factor (the ratio of light area and total area ) can achieve about 90.7% ， so we need higher fill-factor arrays sometimes such as in the compound eye simulation optical system. In order to enhance the fill-factor, we apply the method of the photo etching ionic exchange to manufacture hexagon aperture planar microlens array with the center distance as 160μm .We present a real photograph and an imaging photograph of the array and we apply Jamin Interference method to manufacture hexagon aperture planar micro-lens array’s interference slice and draw the refractive index distribution curve. In the use of ray equations in integral form paraxial optical properties of microlens arrays are studied here. The ray trajectory equation and imaging of microlens arrays are presented. Mathematics expressions of images distance focal length by ABCD law are obtained. This array is arranged in order with a uniform optical feature after the exchange of ions. It has a high fill-factor and a good quality of image along with slight overlaps in the area of Gradient-Index.