Abstract: A folding lens system includes: a polarization-dependence device, a first optical device, a first polarization controller, a second optical device and a second polarization controller. The polarization-dependence device has a first surface and a second surface opposite to the first surface. The first optical device is located at a side facing toward the first surface of the polarization-dependence device. The first polarization controller is located between the polarization-dependence device and the first optical device. The first polarization controller has the same curvature as the first surface of the polarization-dependence device. The second optical device is located at a side facing toward the second surface of the polarization-dependence device. The second polarization controller is located between the polarization-dependence device and the second optical device. The second polarization controller has the same curvature as the second surface of the polarization-dependence device.

Abstract: A rear-wheel skating shoe provides an enhanced shoe stand with a single fulcrum for a wheel axle to make the structure at positions between a sidewall and a wheel axle and between a sidewall and a bottom plate of the shoe stand stronger to facilitate exposing luminous wheels and protect a user's safety effectively. The shoe includes a left shoe stand, a right shoe stand, a metal screw rod at external sidewalls of the shoe stands, a luminous wheel on the metal screw rod, a left reinforced stand in a sidewall of the left shoe stand, a right reinforced stand in a sidewall of the right shoe stand, and a reinforced plate at the bottom of the bottom plate of the shoe stand and connected to the right reinforced stand. The metal reinforced elements of the skating shoe give a strong structure, and the luminous wheels provide a color effect.