Array substrate, method for preparing array substrate, display panel and display apparatus

An array substrate, comprising:

• a base substrate;
• an excitation light source on a side of the base substrate;
• and
• a sub pixel on a side, facing away from the base substrate, of the excitation light source;
• wherein the sub pixel at least comprises:
• a first-kind sub pixel;
• wherein the first-kind sub pixel comprises:
• a first quantum dot conversion layer, a first recycling component layer and a first color film layer sequentially located on the side, facing away from the base substrate, of the excitation light source;
• wherein the first recycling component layer is configured to limit at least part of light with a wavelength, smaller than a wavelength of emergent light of the first-kind sub pixel, into the first quantum dot conversion layer;
• a refractive index of the first recycling component layer is equal to a refractive index of the first color film layer;
• in a wave band smaller than the wavelength of the emergent light of the first-kind sub pixel, a refractive index of the first quantum dot conversion layer is greater than the refractive index of the first recycling component layer;
• and
• in a wave band greater than or equal to the wavelength of the emergent light of the first-kind sub pixel, the refractive index of the first quantum dot conversion layer is smaller than the refractive index of the first recycling component layer.