An optical element comprising at least one strip-shaped optical lens, wherein, in a cross-section perpendicular to a length direction, the optical lens comprises: a light source setting portion, provided for setting the light source with a central axis; a light incident surface, disposed facing the light source setting portion, wherein incident light rays of the light source comprise small-angle light rays and large-angle light rays; two first total reflection surfaces located opposite to the light incident surface and each disposed on opposite sides of the central axis, wherein the two ends of the two first total reflection surfaces close to the light source setting portion are close to each other, for total reflection of the small-angle light rays emitted to the first total reflection surfaces; two first light emitting surfaces arranged on either side of the two first total reflection surfaces in a direction perpendicular to the central axis, for emitting reflected light from the first total reflection surfaces on the same side; two second total reflection surfaces located opposite to the light incident surface and each disposed on opposite sides of the central axis, wherein the two second total reflection surfaces are angled outwards for total reflection of the large-angle light rays in the direction of the small-angle light rays; and two second light emitting surfaces disposed on opposite sides of the central axis and each located between the second total reflection surface and the first light emitting surface on the same side, for emitting reflected light from the second total reflection surface on the same side; wherein the second total reflection surface and the second light emitting surface on either side of the central axis are connected to form an acute angle. a light source setting portion, provided for setting the light source with a central axis; a light incident surface, disposed facing the light source setting portion, wherein incident light rays of the light source comprise small-angle light rays and large-angle light rays; two first total reflection surfaces located opposite to the light incident surface and each disposed on opposite sides of the central axis, wherein the two ends of the two first total reflection surfaces close to the light source setting portion are close to each other, for total reflection of the small-angle light rays emitted to the first total reflection surfaces; two first light emitting surfaces arranged on either side of the two first total reflection surfaces in a direction perpendicular to the central axis, for emitting reflected light from the first total reflection surfaces on the same side; two second total reflection surfaces located opposite to the light incident surface and each disposed on opposite sides of the central axis, wherein the two second total reflection surfaces are angled outwards for total reflection of the large-angle light rays in the direction of the small-angle light rays; and two second light emitting surfaces disposed on opposite sides of the central axis and each located between the second total reflection surface and the first light emitting surface on the same side, for emitting reflected light from the second total reflection surface on the same side; wherein the second total reflection surface and the second light emitting surface on either side of the central axis are connected to form an acute angle.