Polarizer-free LED displays
Exemplary subpixel structures include a directional light-emitting diode structure characterized by a full-width-half-maximum (FWHM) of emitted light having a divergence angle of less than or about 10°. The subpixel structure further includes a lens positioned a first distance from the light-emitting diode structure, where the lens is shaped to focus the emitted light from the light-emitting diode structure. The subpixel structure still further includes a patterned light absorption barrier positioned a second distance from the lens. The patterned light absorption barrier defines an opening in the barrier, and the focal point of the light focused by the lens is positioned within the opening. The subpixels structures may be incorporated into a pixel structure, and pixel structures may be incorporated into a display that is free of a polarizer layer.
1 . A light-emitting subpixel structure comprising:
a directional light-emitting diode structure characterized by a full-width-half-maximum (FWHM) of emitted light having a divergence angle of less than or about 10°;
a lens shaped to focus the emitted light from the light-emitting diode structure; and
a patterned light absorption barrier that defines an opening in which a focal point of the emitted light focused by the lens is positioned within the opening.
2 . The light-emitting subpixel structure of claim 1 , wherein the light-emitting subpixel structure is free of a polarizer layer.
3 . The light-emitting subpixel structure of claim 1 , wherein the light exiting the opening in the patterned light absorption barrier is characterized by a viewing angle that is greater than or about 45°.
4 . The light-emitting subpixel structure of claim 1 , wherein a first distance between the light-emitting diode structure and the lens is greater than a second distance between the lens and the patterned light absorption barrier.
5 . The light-emitting subpixel structure of claim 1 , wherein the lens is characterized by a diameter that is greater than or about 10 μm.
6 . The light-emitting subpixel structure of claim 1 , wherein the opening defined in the patterned light absorption barrier is characterized by a width of less than or about 1 μm.
7 . The light-emitting subpixel structure of claim 1 , wherein the patterned light absorption barrier is characterized by a thickness that is less than or about 10 μm.
8 . The light-emitting subpixel structure of claim 1 , wherein the light-emitting diode structure comprises an organic light-emitting diode structure.
9 . A light-emitting pixel structure comprising:
light-emitting diode structures;
a patterned light absorption barrier defining a group of openings in the barrier, wherein each of the openings permit transmission of light emitted from one of the light-emitting diode structures through the patterned light absorption barrier; and
a plurality of lenses shaped to concentrate the light emitted from the light-emitting diode structures into the openings of the patterned light absorption barrier, wherein each lens in the plurality of lenses is characterized by a ratio of a focal point of the lens to a diameter of the lens that is less than or about 1:1.
10 . The light-emitting pixel structure of claim 9 , wherein each of the light-emitting diode structures is characterized by a full-width-half-maximum (FWHM) of emitted light having a divergence angle of less than or about 10°.
11 . The light-emitting pixel structure of claim 9 , wherein the light exiting the light-emitting pixel structure is characterized by a viewing angle that is greater than or about 45°.
12 . The light-emitting pixel structure of claim 9 , wherein the light-emitting pixel structure is greater than or about 50% brighter than a comparable light-emitting pixel structure with a polarizer.
13 . The light-emitting pixel structure of claim 9 , wherein the light-emitting diode structures comprise organic light-emitting diode structures.
14 . A processing method to form a light-emitting pixel, the method comprising:
forming light-emitting diode structures over a substrate that are characterized by a full-width-half-maximum (FWHM) of emitted light having a divergence angle of less than or about 10°;
forming lenses over the light-emitting diode structures, wherein the lenses are operable to focus light emitted from the light-emitting diode structures; and
forming a patterned light absorption barrier over the lenses, wherein the patterned light absorption barrier defines a group of openings in the barrier to transmit light from the light-emitting diode structures through the barrier such that focal points of the light focused by the lenses are positioned within the group of openings.
15 . The method of claim 14 , wherein the patterned light absorption barrier is formed by:
depositing a layer of a light-absorbing material over the lenses, wherein the layer of the light-absorbing material is characterized by an optical density greater than or about 2 μm −1 ; and
forming the openings in the layer of the light-absorbing material to make the patterned light absorption barrier, wherein the openings have a width of less than or about 1 μm.
16 . The method of claim 14 , wherein the light exiting the light-emitting pixel is characterized by a viewing angle that is greater than or about 45°.
17 . The method of claim 14 , wherein the light-emitting pixel is free of a polarizer layer, and wherein the light-emitting pixel is greater than or about 50% brighter than a comparable light-emitting pixel structure with a polarizer.
18 . The method of claim 14 , wherein the light-emitting pixel comprises an organic light-emitting pixel.