An array chip design is provided where the chip includes a field region arranged with sites according to a first pitch and at least one track region having a one-dimensional site pattern arranged according to a second pitch that is less dense and is an integer multiple of the first pitch so that observation through pixel-based sensors using one-dimensional quad-cell averaging can be applied in the track region, thereby to attain alignment of the chip to pixel-based optical instrumentation with a higher density of sites.