This paper describes the submicron-spaced lens array process technology which we have successSubmicron spaced lens array process technology fully developed to realize high photosensitivity for an IT-CCD image sensor. has been developed for an IT-CCD ( Interline Transfer Charge Coupled Device ) image sensor to realize the high photosensitivity. The photosensitivity of 0.8~. -spaced lens array has been increased to more than 2.5 times the sensitivity for no-lens, and the effective aperture ratio 68% has been realized in a 1/3-inch optical format 512 (H) X 492 (V) pixels IT-CCD image sensor. By developing a lens simulation, we have found that the rectangular dome-lens shows the highest sensitivity among lenses of various forms for a 1/3-inch IT-CCD image sensor. Experimental results for the rectangular dome-lenses have been well explained by this simu