Patent ID: 7242641

Claim:
A solar cell watch comprising an outer dial and an inner solar cell, the outer dial comprising: a transmissive substrate; a series of projections and recesses formed on a first surface of the substrate oriented toward the inner solar cell, the series of projections and recesses being in regularly distributed disposition over a whole area of the first surface, each of the projections being disposed between recesses; a nontransmissive film formed on a whole inner surface of each of the recesses; a transmissive portion formed on a top of each of the projections; and a light passage being formed in each of the projections, such that light outside the dial assembly passes through the light passage, wherein the width of the light passages is 70 μm or less, and the total area of the light passages is between 20 and 50% of the area of a second surface opposite the first surface.