By applying Gaussian optics we propose a new matrix formula model for intraocular lens (IOL) calculation that yields not only IOL optical power for a particular eye but also an evaluation of the bending factor of different IOL optical designs. This option improves IOL selection and results in the best possible optical image, a function dependent on the IOL's bending factor. This formula is a new approach to IOL calculation and may be useful in designing IOLs for abnormally hyperopic or myopic eyes. Optimal IOL power and design should both be considered in IOL calculation, which may improve the optical and clinical results of IOL implantation in the aphakic patient. The radius of the cornea is assumed to be spherical, and aspherical curves of the cornea may influence the optimal "bending" or shape factor of a lens.