A display panel, comprising: a polarizer, configured to convert light incident from a light-incident surface thereof into a linearly polarized light emitted out from a light-emitting surface thereof; a plurality of optical adjustment layers stacked one over another and arranged over the light-emitting surface of the polarizer, each comprising: a polarization direction-adjusting sub-layer comprising a plurality of adjusting portions, configured to adjustably control a polarization direction of an incident polarized light; and a quantum rod sub-layer over a surface of the polarization direction-adjusting sub-layer distal to the polarizer, comprising a plurality of light-excitement portions and configured to change a wavelength of the incident polarized light, wherein each of the plurality of light-excitement portions comprises a plurality of quantum rods, each configured to have a long axis thereof to be in a substantially same direction, wherein the plurality of adjusting portions in the polarization direction-adjusting sub-layer and the plurality of light-excitement portions in the quantum rod sub-layer in each of the plurality of optical adjustment layers respectively correspond to a plurality of display units, configured such that an orthographic projection of one light-excitement portion corresponding to a display unit on the polarizer overlaps with an orthographic projection of one adjusting portion corresponding to a same display unit on the polarizer, and wherein the plurality of optical adjustment layers are configured such that: each light-excitement portion in a same quantum rod sub-layer is capable of emitting light having a substantially same color upon excitement; and each light-excitement portion in a different quantum rod sub-layer is capable of emitting light having a different color upon excitement. a polarizer, configured to convert light incident from a light-incident surface thereof into a linearly polarized light emitted out from a light-emitting surface thereof; a plurality of optical adjustment layers stacked one over another and arranged over the light-emitting surface of the polarizer, each comprising: a polarization direction-adjusting sub-layer comprising a plurality of adjusting portions, configured to adjustably control a polarization direction of an incident polarized light; and a quantum rod sub-layer over a surface of the polarization direction-adjusting sub-layer distal to the polarizer, comprising a plurality of light-excitement portions and configured to change a wavelength of the incident polarized light, wherein each of the plurality of light-excitement portions comprises a plurality of quantum rods, each configured to have a long axis thereof to be in a substantially same direction, wherein the plurality of adjusting portions in the polarization direction-adjusting sub-layer and the plurality of light-excitement portions in the quantum rod sub-layer in each of the plurality of optical adjustment layers respectively correspond to a plurality of display units, configured such that an orthographic projection of one light-excitement portion corresponding to a display unit on the polarizer overlaps with an orthographic projection of one adjusting portion corresponding to a same display unit on the polarizer, and a polarization direction-adjusting sub-layer comprising a plurality of adjusting portions, configured to adjustably control a polarization direction of an incident polarized light; and a quantum rod sub-layer over a surface of the polarization direction-adjusting sub-layer distal to the polarizer, comprising a plurality of light-excitement portions and configured to change a wavelength of the incident polarized light, wherein each of the plurality of light-excitement portions comprises a plurality of quantum rods, each configured to have a long axis thereof to be in a substantially same direction, wherein the plurality of adjusting portions in the polarization direction-adjusting sub-layer and the plurality of light-excitement portions in the quantum rod sub-layer in each of the plurality of optical adjustment layers respectively correspond to a plurality of display units, configured such that an orthographic projection of one light-excitement portion corresponding to a display unit on the polarizer overlaps with an orthographic projection of one adjusting portion corresponding to a same display unit on the polarizer, and wherein the plurality of optical adjustment layers are configured such that: each light-excitement portion in a same quantum rod sub-layer is capable of emitting light having a substantially same color upon excitement; and each light-excitement portion in a different quantum rod sub-layer is capable of emitting light having a different color upon excitement. each light-excitement portion in a same quantum rod sub-layer is capable of emitting light having a substantially same color upon excitement; and each light-excitement portion in a different quantum rod sub-layer is capable of emitting light having a different color upon excitement.