US Patent 11067316 Cooling with anti-stokes fluorescence

A double or multi-layer apparatus or device for optical anti-Stokes cooling of object surfaces. The apparatus comprises at least one bottom layer, which is configured to respond in anti-Stokes fluorescence upon absorption of electromagnetic radiation and at least one top layer, which is overlaid on the bottom layer and configured to filter the electromagnetic radiation and transmit selected spectral band of the electromagnetic radiation to the bottom layer. The active cooling does not depend on the coherent nature of the radiation, which enables the usage of incoherent solar radiation as the active cooling input power source. The cooling technology of the invention is suitable for small and large scales and practically for any object with surface on which the layer substance can be applied or overlaid, e.g., roof, wall, car, ship, tent, clothing, etc.