axes w 1 r w 1 l are then bent by longitudinally stacked reflecting prisms wm 2 r wm 2 l in such a way as to run in the same direction while they are mutually parallel and longitudinally in alignment in this embodiment one common filter wf is provided for both optical systems osr and osl as shown in fig3 in this embodiment the long sides of such a rectangular image pickup plane w 12 as shown in fig4 of an image pickup device w 10 are positioned in the longitudinal direction in such a way that an image plane wir for the right optical path formed by the superwide angle optical system osr and an image plane wil for the left optical path formed by the superwide angle lens optical system osl both having mutual parallaxes are formed on that image pickup plane w 12 longitudinally in alignment thus the optical axes w 1 r w 1 l strike from the vertically stacked reflecting prisms wm 2 r wm 2 l vertically on the image pickup plane w 12 with such arrangement a wide field is assured in both the lateral and longitudinal directions even when the single image pickup device w 10 is used such optical system arrangements are well fit for the optical systems in onboard cameras needed for looking ahead and aside or the like especially those onboard cameras and surveillance cameras for looking behind as the optical path is taken part the optical axis w 1 r w 1 l of the superwide angle lens optical system osr osl takes.