The lines you see do not exist. It is made of 8 checkerboards that technically should overlap and abut each other perfectly to create only black. Only when the grids are rotated away from 0º do these lines appear in the theoretically non-existent negative spaces as imperfect edges revealed by the medium of pixels.
V.02 Note: v.01 was murdered by compression. This one is up-scaled by double, but still has some compression issues though at least is more clear. If anyone wants to be sent an uncompressed version to look at or play with shoot me an email.