Choosing a camera (1)
The TFT displays consist of 640 pixels in 240 lines. The goal is : 1 display dot (one of the colour pixels) should be contained in at least 2 camera pixels.
I.e.: In the horizontal direction we need >= 640 x 3 x 2 = 3840 camera pixels. The resolution in vertical direction is not as critical as that in horizontal direction.