A method to improve the module efficiency of solar cells by modifying the surface of the glass cover of the solar cells module is proposed. A model is built to show that a better efficiency can be achieved by optimizing the light distribution on the cell, which reduces the shadow losses and thereby allows the finger spacing to be decreased, which in turn decreases the (resistive) ohmic losses. This method is illustrated by considering industrial crystalline silicon solar cells as an example, however, it applies to all solar cells that are characterized by a metallization pattern on the surface of the solar cell. It is estimated that this method can improve the relative module efficiency by about 5% and halve the front side losses. (C) 2009 Elsevier Ltd. All rights reserved.