PBP MICRO-LENS FOR MICRO-OLED BEAM TUNING
A micro-light emitting diode device includes a backplane including drive circuits formed thereon, an array of micro-LEDs bonded to the backplane and electrically coupled to the drive circuits, an array of polarization diffraction micro-lenses bonded to the array of micro-LEDs and including a planar surface, and a cover glass bonded to the planar surface of the array of polarization diffraction micro-lenses. A center of each polarization diffraction micro-lens of the array of polarization diffraction micro-lenses aligns with a center of a respective micro-LED of the array of micro-LEDs.
1 . A micro-light emitting diode (micro-LED) device comprising:
a backplane including drive circuits formed thereon;
an array of micro-LEDs bonded to the backplane and electrically coupled to the drive circuits;
an array of polarization diffraction micro-lenses bonded to the array of micro-LEDs and including a planar surface, wherein a center of each polarization diffraction micro-lens of the array of polarization diffraction micro-lenses aligns with a center of a respective micro-LED of the array of micro-LEDs; and
a cover glass bonded to the planar surface of the array of polarization diffraction micro-lenses.
2 . The micro-LED device of claim 1 , wherein the array of polarization diffraction micro-lenses is configured to collimate light beams emitted by the array of micro-LEDs.
3 . The micro-LED device of claim 2 , wherein the array of polarization diffraction micro-lenses is configured to deflect chief rays of light beams emitted by the array of micro-LEDs by different deflection angles that gradually increase from a center of the micro-LED device to an edge of the micro-LED device.
4 . The micro-LED device of claim 1 , wherein an optical axis of a polarization diffraction micro-lens of the array of polarization diffraction micro-lenses is offset from the center of the polarization diffraction micro-lens.
5 . The micro-LED device of claim 1 , wherein:
a first polarization diffraction micro-lens of the array of polarization diffraction micro-lenses is characterized by a first offset between an optical axis of the first polarization diffraction micro-lens and the center of the first polarization diffraction micro-lens; and
a second polarization diffraction micro-lens of the array of polarization diffraction micro-lenses is characterized by a second offset between an optical axis of the second polarization diffraction micro-lens and the center of the second polarization diffraction micro-lens, wherein the second offset is different from the first offset.
6 . The micro-LED device of claim 1 , wherein each polarization diffraction micro-lens of the array of polarization diffraction micro-lenses is characterized by a positive optical power for light of a first circular polarization state and a negative optical power for light of a second circular polarization state.
7 . The micro-LED device of claim 1 , wherein the array of polarization diffraction micro-lenses includes Pancharatnam-Berry Phase (PBP) micro-lenses.
8 . The micro-LED device of claim 1 , wherein each polarization diffraction micro-lens of the array of polarization diffraction micro-lenses includes:
an alignment layer including an alignment pattern formed thereon; and
liquid crystal molecules arranged according to the alignment pattern.
9 . The micro-LED device of claim 1 , wherein a pitch of the array of micro-LEDs is equal to a pitch of the array of polarization diffraction micro-lenses.
10 . The micro-LED device of claim 1 , wherein the array of micro-LEDs includes:
an array of micro-organic light emitting diodes (micro-OLEDs) configured to emit red, green, and blue light;
an array of III-V semiconductor micro-LEDs configured to emit red, green, and blue light; or
an array of color filters and an array of micro-OLEDs configured to emit white light.
11 . The micro-LED device of claim 1 , wherein the array of micro-LEDs includes an array of pixels, each pixel of the array of pixels including:
a first micro-LED configured to emit light in a first wavelength range;
a second micro-LED configured to emit light in a second wavelength range; and
a third micro-LED configured to emit light in a third wavelength range,
herein three polarization diffraction micro-lenses of the array of polarization diffraction micro-lenses are configured to deflect chief rays of light beams emitted by the first micro-LED, the second micro-LED, and the third micro-LED by a same deflection angle.
12 . The micro-LED device of claim 1 , further comprising a circular polarizer.
13 . A near-eye display system comprising:
an image source configured to generate display light, the image source comprising:
a backplane including drive circuits formed thereon;
an array of micro-LEDs bonded to the backplane and electrically coupled to the drive circuits;
an array of polarization diffraction micro-lenses aligned with the array of micro-LEDs and including a planar surface, wherein a pitch of the array of polarization diffraction micro-lenses is equal to a pitch of the array of micro-LEDs; and
a cover glass bonded to the planar surface of the array of polarization diffraction micro-lenses; and
display optics configured to project the display light emitted by the image source to an eye box of the near-eye display system.
14 . The near-eye display system of claim 13 , wherein the array of polarization diffraction micro-lenses is configured to direct chief rays of light beams emitted by the array of micro-LEDs onto the display optics at different incident angles.
15 . The near-eye display system of claim 13 , wherein the array of polarization diffraction micro-lenses is configured to deflect chief rays of light beams emitted by the array of micro-LEDs by different deflection angles that gradually increase from a center of the image source to an edge of the image source.
16 . The near-eye display system of claim 13 , wherein an optical axis of a polarization diffraction micro-lens of the array of polarization diffraction micro-lenses is offset from a center of the polarization diffraction micro-lens.
17 . The near-eye display system of claim 13 , wherein the array of polarization diffraction micro-lenses includes Pancharatnam-Berry Phase (PBP) micro-lenses, each PBP micro-lens of the PBP micro-lenses characterized by a positive optical power for light of a first circular polarization state and a negative optical power for light of a second circular polarization state.
18 . The near-eye display system of claim 13 , wherein each polarization diffraction micro-lens of the array of polarization diffraction micro-lenses includes:
an alignment layer including an alignment pattern formed thereon; and
liquid crystal molecules arranged according to the alignment pattern.
19 . The near-eye display system of claim 13 , wherein the array of micro-LEDs includes:
an array of micro-organic light emitting diodes (micro-OLEDs) configured to emit red, green, and blue light;
an array of III-V semiconductor micro-LEDs configured to emit red, green, and blue light; or
an array of color filters and an array of micro-OLEDs configured to emit white light.
20 . The near-eye display system of claim 13 , further comprising a circular polarizer between the image source and the display optics.