1. A color image sensor for generating a color image signal representing a subject, the image sensor comprising: an imaging element array configured as a unitary, open-bottomed box comprising: an optical substrate including: a first imaging element comprising a first refractive surface defined in an external major surface of the optical substrate, and a second imaging element comprising a second refractive surface defined in the external major surface of the optical substrate, the first and second refractive surfaces each configured to image light of a respectively different color, a plurality of side portions of the open-bottomed box, and a screen extending from one side portion to an opposite side portion of the open-bottomed box between the first and the second imaging elements for separating the first and second imaging elements, the screen including a light absorbing material such that (1) light imaged by the first imaging element is blocked by the screen from being incident on a second region of sensor elements, and (2) light imaged by the second imaging element is blocked by the screen from being incident on a first region of sensor elements; and a light sensor configured on a further substrate, the light sensor comprising: the first and second regions of sensor elements disposed on the further substrate opposite the first and second imaging elements, respectively, and one or more attachment pads attached to the further substrate for aligning the imaging element array to the light sensor and for affixing the imaging element array to the further substrate, the one or more attachment pads affixed to and aligned with the plurality of side portions and the screen using solder such that the first and second regions of sensor elements are encapsulated inside the unitary open-bottomed box.