Abstract:
An inorganic-light-emitter display includes a display substrate and a plurality of spatially separated inorganic light emitters distributed on the display substrate in a light-emitter layer. A light-absorbing layer located on the display substrate in the light-emitter layer is in contact with the inorganic light emitters. Among other things, the disclosed technology provides improved angular image quality by avoiding parallax between the light emitters and the light-absorbing material, increased light-output efficiency by removing the light-absorbing material from the optical path, improved contrast by increasing the light-absorbing area of the display substrate, and a reduced manufacturing cost in a mechanically and environmentally robust structure using micro transfer printing.

Description:
PRIORITY APPLICATION 
     This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/169,520, filed Jun. 1, 2015, titled “Inorganic-Light-Emitter Display with Integrated Black Matrix,” the contents of which are incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a display including inorganic light emitters and a black matrix for reducing ambient light reflections. 
     BACKGROUND OF THE INVENTION 
     Flat-panel displays are widely used in conjunction with computing devices, in portable devices, and for entertainment devices such as televisions. Such displays typically employ a plurality of pixels distributed over a display substrate to display images, graphics, or text. For example, liquid crystal displays (LCDs) employ liquid crystals to block or transmit light from a backlight behind the liquid crystals and organic light-emitting diode (OLED) displays rely on passing current through a layer of organic material that glows in response to the electrical current. 
     Most flat-panel displays are either reflective or emissive. Reflective displays, such as many e-paper displays and reflective LCDs do not emit light but rather each of the display pixels reflects or absorbs ambient light to form an image. Such displays cannot be viewed in the dark but excel in bright conditions such as a sunny day outdoors. In contrast, light-emissive displays emit light and can be viewed in the dark but are often difficult to view in bright conditions. 
     In order to improve the display contrast of light-emissive displays, display designers typically use anti-reflection layers on the front cover of displays and light-absorbing layers internal to the display to reduce ambient light reflection. For example, OLED displays often employ circular polarizers on the cover glass and LCDs use an ambient-light-absorbing black matrix in combination with color filters used to color the white light emitted by the LCD backlights. These black-matrix structures are either in a common structure with the color filters or between the viewer and the color filter. For example, U.S. Pat. No. 6,466,281 entitled Integrated black matrix/color filter structure for TFT-LCD describes a light-shielding layer located above the switching transistors in the display. U.S. Patent Application Publication No. 2007/0077349 entitled Patterning OLED Device Electrodes and Optical Material describes a black matrix integrated into an electrically insulating layer to absorb unwanted light in an RGBW configuration. Similarly, U.S. Pat. No. 7,402,951 entitled OLED Device having Improved Contrast discloses a contrast enhancement element with a light-absorbing layer for absorbing ambient light. U.S. Pat. No. 6,812,637, U.S. Pat. No. 7,466,075, and U.S. Pat. No. 7,091,523 all describe the use of black-matrix structures to improve contrast. These light-absorbing elements or layers are located between a viewer and the light-emitting OLED pixels. 
     Outdoor inorganic LED displays for public viewing are known to have black louvers associated with individual pixels to reduce glare from the sun. However, such displays are not capable of high resolution. 
     Inorganic LED displays are also known to use black-matrix structures, as disclosed in U.S. Pat. No. 7,919,342 entitled Patterned Inorganic LED Device in which a patterned conductive layer between and above the patterned light emitters can act as a black matrix to absorb light and increase the display contrast. 
     Black matrix structures in conventional displays locate light-absorbing elements or layers between a viewer and the light-emitting OLED pixels. Although such an arrangement can be relatively effective in absorbing ambient light, they also absorb emitted light and can create viewing-angle dependence for brightness. Such multi-layer structures are more complex and costly to manufacture and the additional layers can also absorb emitted light, reducing display efficiency. Thus, there remains a need for improvements in display systems, structures, and methods of manufacturing that provide improved image quality and contrast, emission efficiency, and a reduced manufacturing cost in a mechanically and environmentally robust structure. 
     SUMMARY OF THE INVENTION 
     The present invention provides a display having a plurality of spatially separated inorganic light emitters distributed over a display substrate in a light-emitter layer. A light-absorbing material is formed over the display substrate in the light-emitter layer and in contact with the inorganic light emitters. This arrangement provides the light emitters in a common layer with the light-absorbing material so that very little, if any, emitted light is absorbed by the light-absorbing material, improving the light output efficiency of the display. Moreover, since the light emitters are in a common layer with the light-absorbing material, there is no parallax between the light emitters and the light absorbing layer and thus no angular dependence on the light absorption or emission due to the light-absorbing material. Since an additional layer for incorporating the light-absorbing material is unnecessary, there is no further emitted light loss or additional manufacturing steps due to such an additional layer. Thus, the light-absorbing material absorbs ambient light but little or no emitted light. 
     The light emitters can be embedded in the light-absorbing material, providing additional robustness and environmental protection to the display. Furthermore, since an embodiment of the present invention uses micro-LEDs as the light emitters, the aperture ratio of the display can be relatively small and the light-absorbing material area is relatively large, contrary to prior-art displays, so that the ambient light is effectively absorbed by the light-absorbing material. Furthermore, in a small-aperture-ratio display using micro-LEDs, the problem of angular dependence for brightness due to parallax with a black matrix in a layer between the micro-LEDs and the viewer is particularly acute. According to embodiments of the present invention, because the light emitters are in a common layer with the light-absorbing material, this problem does not arise. 
     Among other things, the disclosed technology provides improved angular image quality by avoiding parallax between the light emitters and the light-absorbing material, increased light-output efficiency by removing the light-absorbing material from the optical path, improved contrast by increasing the light-absorbing area of the display substrate, and a reduced manufacturing cost in a mechanically and environmentally robust structure using micro transfer printing. 
     In one aspect, the disclosed technology includes an inorganic-light-emitter display, the display including: a display substrate; a plurality of spatially separated inorganic light emitters distributed on the display substrate in a light-emitter layer; and a light-absorbing material surrounding at least a portion of the plurality of inorganic light emitters in the light-emitter layer, wherein the light-absorbing material at least partially covers the display substrate. 
     In certain embodiments, the display includes a transparent adhesive layer located between the display substrate and the plurality of spatially separated inorganic light emitters that adheres the spatially separated inorganic light emitters to the display substrate. 
     In certain embodiments, the transparent adhesive layer is index-matched to the display substrate or to an element of the inorganic light emitters. 
     In certain embodiments, the transparent adhesive layer has a thickness that causes constructive optical interference for one or more of the frequencies of light emitted by the inorganic light emitters or that causes destructive optical interference for at least some frequencies of ambient light. 
     In certain embodiments, the display includes one or more pixel controllers located at least partially over the light-absorbing material and electrically connected to the inorganic light emitters. 
     In certain embodiments, the display includes one or more pixel controllers disposed on the display substrate, the pixel controllers connected to the inorganic light emitters with electrical connections, and the pixel controllers and the electrical connections located at least partially between the light-absorbing layer and the display substrate. 
     In certain embodiments, the display includes optical vias in the light-absorbing layer, the optical vias located at least partially in correspondence with the light-emitting areas of the inorganic light emitters. 
     In certain embodiments, the plurality of inorganic light emitters and the light-absorbing material are disposed on a common surface. 
     In certain embodiments, the inorganic light emitters include semiconductor layers and an electrically insulating layer disposed between the semiconductor layers and the light-absorbing material. 
     In certain embodiments, the light-emitter layer includes an electrically insulating layer disposed between the inorganic light emitters and the light-absorbing material. 
     In certain embodiments, the display includes an interlayer dielectric disposed between the inorganic light emitters and the light-absorbing material. 
     In certain embodiments, the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm. 
     In certain embodiments, the light-absorbing material is in contact with one or more of the light emitters of the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is contiguous and surrounds the plurality of inorganic light emitters on the display substrate. 
     In certain embodiments, the light-absorbing material is a curable resin that includes a light-absorbing dye or pigment. 
     In certain embodiments, the display substrate has a transparency greater than or equal to 50%, 80%, 90%, or 95% for visible light. 
     In certain embodiments, the inorganic light emitters are inorganic light-emitting diodes. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, the display includes a plurality of pixels, each pixel comprising one or more of the plurality of inorganic light emitters. 
     In certain embodiments, each pixel of the plurality of pixels has inorganic light emitters that emit different colors of light. 
     In certain embodiments, the plurality of light emitters includes: a plurality of red micro inorganic light-emitting diodes, a plurality of green micro inorganic light-emitting diodes, and a plurality of blue micro inorganic light-emitting diodes, wherein each pixel of the plurality of pixels comprises a red micro inorganic light-emitting diode of the plurality of red micro inorganic light-emitting diodes, a green micro inorganic light-emitting diode of the plurality of green micro inorganic light-emitting diodes, and a blue micro inorganic light-emitting diode of the plurality of blue micro inorganic light-emitting diodes. 
     In certain embodiments, the plurality of light emitters comprise a plurality of yellow light emitters, and each pixel of the plurality of pixels comprises a yellow micro inorganic light-emitting diode of the plurality of yellow micro inorganic light-emitting diodes. 
     In certain embodiments, each pixel of the plurality of pixels is spatially separated from two or more adjacent pixels by a first distance, each pixel comprises two or more inorganic light emitters of the plurality of inorganic light emitters, each of the two or more inorganic light emitters with a pixel are spatially separated from an adjacent inorganic light emitter within the pixel by a second distance, and the first distance is greater than the second distance. 
     In certain embodiments, the plurality of pixels forms an array. 
     In certain embodiments, the light-absorbing material is within the spatial area encompassed by the plurality of pixels. 
     In certain embodiments, the display substrate is transparent and the plurality of inorganic light emitters are disposed on the display substrate to emit light through the display substrate. 
     In certain embodiments, the inorganic light emitters emit light in a direction opposite the display substrate. 
     In certain embodiments, each light emitter of the plurality of inorganic light emitters has a light-emissive area and wherein the combined light-emissive areas of the plurality of inorganic light emitters is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, or one ten-thousandth of the light-absorbing material area. 
     In certain embodiments, at least one or more of the plurality of inorganic light emitters is at least partially between the light-absorbing material and the display substrate. 
     In certain embodiments, the light-absorbing material covers a display area of the display substrate. 
     In certain embodiments, the display includes electrically conductive wires formed on or over the display substrate and electrically connected to the inorganic light emitters. 
     In certain embodiments, the wires are located between the light-absorbing material and the display substrate and comprising a light filter between the wires and the display substrate. 
     In certain embodiments, the light filter is a dichroic filter. 
     In certain embodiments, the light filter is a black metal, is carbon, or is carbon black. 
     In certain embodiments, the light-absorbing material includes multiple layers of light-absorbing material and the wires are located between the layers. 
     In certain embodiments, the display includes an anti-reflection layer located between the plurality of inorganic light emitters and a viewer. 
     In certain embodiments, the light-absorbing material absorbs ambient light transmitted through the display substrate. 
     In certain embodiments, the display substrate is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. 
     In certain embodiments, the display substrate is flexible. 
     In certain embodiments, the display includes a protection layer located between the light emitters and a viewer. 
     In certain embodiments, the display includes a removal layer located on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the display includes vias formed in the light-absorbing material where the light-absorbing material overlaps the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is deposited by spin, curtain, or hopper coating the display substrate with the light-absorbing material. 
     In certain embodiments, the display includes a plurality of pixel substrates separate from the display substrate and wherein each of the plurality of inorganic light emitters are located on one of the plurality of pixel substrates and the plurality of pixel substrates are located on the display substrate. 
     In certain embodiments, the pixel substrate includes a material selected from the group consisting of a semiconductor material, plastic, glass, metal, or a combination thereof. 
     In certain embodiments, the common surface on which the plurality of light emitters and the light-absorbing material are formed is a planar surface. 
     In certain embodiments, the display substrate has two opposing smooth sides. 
     In certain embodiments, the plurality of inorganic light emitters are non-native to the display substrate. 
     In certain embodiments, the inorganic light emitters include semiconductor layers and an electrically insulating layer disposed between the semiconductor layers and the light-absorbing material. 
     In certain embodiments, the light-emitter layer includes an electrically insulating layer disposed between the inorganic light emitters and the light-absorbing material. 
     In certain embodiments, the display includes an interlayer dielectric disposed between the inorganic light emitters and the light-absorbing material. 
     In another aspect, the display includes a display substrate; a light-absorbing material in contact with the display substrate; and a plurality of inorganic light emitters distributed on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the plurality of inorganic light emitters distributed on the light-absorbing material are at least partially embedded in the light-absorbing material. 
     In certain embodiments, the display includes one or more pixel controllers connected to the inorganic light emitters on the side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the light-absorbing material forms a first layer and comprising a second layer of light-absorbing material on the first layer, the pixel controllers and the connections. 
     In certain embodiments, the display includes inorganic light emitter optical vias in the second layer. 
     In certain embodiments, a surface of each of the plurality of inorganic light emitters are flush with a surface of the light-absorbing material. 
     In certain embodiments, the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm. 
     In certain embodiments, the light-absorbing material is in contact with one or more of the light emitters of the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is contiguous and surrounds the plurality of inorganic light emitters on the display substrate. 
     In certain embodiments, the light-absorbing material is a curable resin that includes a light-absorbing dye or pigment. 
     In certain embodiments, the display substrate has a transparency greater than or equal to 50%, 80%, 90%, or 95% for visible light. 
     In certain embodiments, the inorganic light emitters are inorganic light-emitting diodes. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, the display includes a plurality of pixels, each pixel comprising one or more of the plurality of inorganic light emitters. 
     In certain embodiments, each pixel of the plurality of pixels has inorganic light emitters that emit different colors of light. 
     In certain embodiments, the plurality of light emitters includes: a plurality of red micro inorganic light-emitting diodes, a plurality of green micro inorganic light-emitting diodes, and a plurality of blue micro inorganic light-emitting diodes, wherein each pixel of the plurality of pixels comprises a red micro inorganic light-emitting diode of the plurality of red micro inorganic light-emitting diodes, a green micro inorganic light-emitting diode of the plurality of green micro inorganic light-emitting diodes, and a blue micro inorganic light-emitting diode of the plurality of blue micro inorganic light-emitting diodes. 
     In certain embodiments, the plurality of light emitters comprise a plurality of yellow light emitters, and each pixel of the plurality of pixels comprises a yellow micro inorganic light-emitting diode of the plurality of yellow micro inorganic light-emitting diodes. 
     In certain embodiments, each pixel of the plurality of pixels is spatially separated from two or more adjacent pixels by a first distance, each pixel comprises two or more inorganic light emitters of the plurality of inorganic light emitters, each of the two or more inorganic light emitters with a pixel are spatially separated from an adjacent inorganic light emitter within the pixel by a second distance, and the first distance is greater than the second distance. 
     In certain embodiments, the plurality of pixels forms an array. 
     In certain embodiments, the light-absorbing material is within the spatial area encompassed by the plurality of pixels. 
     In certain embodiments, the display substrate is transparent and the plurality of inorganic light emitters are disposed on the display substrate to emit light through the display substrate. 
     In certain embodiments, the inorganic light emitters emit light in a direction opposite the display substrate. 
     In certain embodiments, each light emitter of the plurality of inorganic light emitters has a light-emissive area and wherein the combined light-emissive areas of the plurality of inorganic light emitters is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, or one ten-thousandth of the light-absorbing material area. 
     In certain embodiments, at least one or more of the plurality of inorganic light emitters is at least partially between the light-absorbing material and the display substrate. 
     In certain embodiments, the light-absorbing material covers a display area of the display substrate. 
     In certain embodiments, the display includes electrically conductive wires formed on or over the display substrate and electrically connected to the inorganic light emitters. 
     In certain embodiments, the wires are located between the light-absorbing material and the display substrate and comprising a light filter between the wires and the display substrate. 
     In certain embodiments, the light filter is a dichroic filter. 
     In certain embodiments, the light filter is a black metal, is carbon, or is carbon black. 
     In certain embodiments, the light-absorbing material includes multiple layers of light-absorbing material and the wires are located between the layers. 
     In certain embodiments, the display includes an anti-reflection layer located between the plurality of inorganic light emitters and a viewer. 
     In certain embodiments, the light-absorbing material absorbs ambient light transmitted through the display substrate. 
     In certain embodiments, the display substrate is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. 
     In certain embodiments, the display substrate is flexible. 
     In certain embodiments, the display includes a protection layer located between the light emitters and a viewer. 
     In certain embodiments, the display includes a removal layer located on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the display includes vias formed in the light-absorbing material where the light-absorbing material overlaps the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is deposited by spin, curtain, or hopper coating the display substrate with the light-absorbing material. 
     In certain embodiments, the display includes a plurality of pixel substrates separate from the display substrate and wherein each of the plurality of inorganic light emitters are located on one of the plurality of pixel substrates and the plurality of pixel substrates are located on the display substrate. 
     In certain embodiments, the pixel substrate includes a material selected from the group consisting of a semiconductor material, plastic, glass, metal, or a combination thereof. 
     In certain embodiments, the common surface on which the plurality of light emitters and the light-absorbing material are formed is a planar surface. 
     In certain embodiments, the display substrate has two opposing smooth sides. 
     In certain embodiments, the plurality of inorganic light emitters are non-native to the display substrate. 
     In certain embodiments, the inorganic light emitters include semiconductor layers and an electrically insulating layer disposed between the semiconductor layers and the light-absorbing material. 
     In certain embodiments, the light-emitter layer includes an electrically insulating layer disposed between the inorganic light emitters and the light-absorbing material. 
     In certain embodiments, the display includes an interlayer dielectric disposed between the inorganic light emitters and the light-absorbing material. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method including: providing a plurality of inorganic light emitters; micro transfer printing the plurality of inorganic light emitters onto a display substrate such that the plurality of inorganic light emitters are spatially separated on the display substrate in a light-emitter layer; and depositing a light-absorbing material on the display substrate in the light-emitter layer and surrounding at least a portion of the plurality of inorganic light emitters, thereby forming a light-absorbing layer on the display substrate. 
     In certain embodiments, the plurality of inorganic light emitters and the light-absorbing material are disposed on a common surface. 
     In certain embodiments, the plurality of inorganic light emitters distributed on the light-absorbing material are at least partially embedded in the light-absorbing material. 
     In certain embodiments, a top surface of each of the plurality of inorganic light emitters are flush with a top surface of the light-absorbing material. 
     In certain embodiments, the plurality of inorganic light emitters are non-native to the display substrate. 
     In certain embodiments, the light-absorbing material is in contract with one or more of the light emitters of the plurality of light emitters. 
     In certain embodiments, the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm. 
     In certain embodiments, the light-absorbing material is contiguous and surrounds the plurality of inorganic light emitters on the display substrate. 
     In certain embodiments, the light-absorbing material is a curable resin that includes a light-absorbing dye or pigment. 
     In certain embodiments, the inorganic light emitters are inorganic light-emitting diodes. 
     In certain embodiments, display substrate has a transparency greater than or equal to 50%, 80%, 90%, or 95% for visible light. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, the display includes a plurality of pixels, each pixel including one or more of the plurality of inorganic light emitters. 
     In certain embodiments, each pixel of the plurality of pixels has inorganic light emitters that emit different colors of light. 
     In certain embodiments, the plurality of light emitters includes: a plurality of red micro inorganic light-emitting diodes, a plurality of green micro inorganic light-emitting diodes, and a plurality of blue micro inorganic light-emitting diodes, wherein each pixel of the plurality of pixels comprises a red micro inorganic light-emitting diode of the plurality of red micro inorganic light-emitting diodes, a green micro inorganic light-emitting diode of the plurality of green micro inorganic light-emitting diodes, and a blue micro inorganic light-emitting diode of the plurality of blue micro inorganic light-emitting diodes. 
     In certain embodiments, the plurality of light emitters comprise a plurality of yellow light emitters, and each pixel of the plurality of pixels comprises a yellow micro inorganic light-emitting diode of the plurality of yellow micro inorganic light-emitting diodes. 
     In certain embodiments, each pixel of the plurality of pixels is spatially separated from two or more adjacent pixels by a first distance, each pixel comprises two or more inorganic light emitters of the plurality of inorganic light emitters, each of the two or more inorganic light emitters within a pixel are spatially separated from an adjacent inorganic light emitter within the pixel by a second distance, and the first distance is greater than the second distance. 
     In certain embodiments, the plurality of pixels forms an array. 
     In certain embodiments, the light-absorbing material is within the spatial area encompassed by the plurality of pixels. 
     In certain embodiments, the display substrate is transparent and the plurality of inorganic light emitters are disposed on the display substrate to emit light through the display substrate. 
     In certain embodiments, the inorganic light emitters emit light in a direction opposite the display substrate. 
     In certain embodiments, each light emitter of the plurality of inorganic light emitters has a light-emissive area and wherein the combined light-emissive areas of the plurality of inorganic light emitters is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, or one ten-thousandth of the light-absorbing material area. 
     In certain embodiments, the plurality of inorganic light emitters are at least partially between the light-absorbing material and the display substrate. 
     In certain embodiments, the light-absorbing material covers display area of the display substrate. 
     In certain embodiments, the display includes electrically conductive wires formed on or over the display substrate and electrically connected to the inorganic light emitters. 
     In certain embodiments, the wires are located between the light-absorbing material and the display substrate and comprising a light filter between the wires and the display substrate. 
     In certain embodiments, the light filter is a dichroic filter. 
     In certain embodiments, the light filter is a black metal, is carbon, or is carbon black. 
     In certain embodiments, the light-absorbing material includes multiple layers of light-absorbing material and the wires are located between the layers. 
     In certain embodiments, the display includes an anti-reflection layer located between the plurality of light emitters and a viewer. 
     In certain embodiments, the light-absorbing material absorbs ambient light transmitted through the display substrate. 
     In certain embodiments, the display substrate is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. 
     In certain embodiments, the display substrate is flexible. 
     In certain embodiments, the display includes a protection layer located between the light emitters and a viewer. 
     In certain embodiments, the display includes a removal layer located on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the method includes forming vias in the light-absorbing material where the light-absorbing material overlaps the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is deposited by spin, curtain, or hopper coating the display substrate with the light-absorbing material. 
     In certain embodiments, the method includes providing a plurality of pixel substrates separate from the display substrate and wherein each of the plurality of inorganic light emitters are located on one of the plurality of pixel substrates and the plurality of pixel substrates are located on the display substrate. 
     In certain embodiments, the pixel substrate includes a material selected from the group consisting of a semiconductor material, plastic, glass, metal, or a combination thereof. 
     In certain embodiments, the common surface on which the plurality of light emitters and the light-absorbing material are formed is a planar surface. 
     In certain embodiments, the display substrate has two opposing smooth sides. 
     In certain embodiments, the display substrate is non-native to the plurality of inorganic light emitters. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method including: providing a plurality of inorganic light emitters; depositing a light-absorbing material on a display substrate, thereby forming a light-absorbing layer on the display substrate; and micro transfer printing the plurality of inorganic light emitters onto the light-absorbing material. 
     In certain embodiments, the light-absorbing material forms a first layer and depositing a second layer of light-absorbing material on the first layer and at least partially between the inorganic light emitters. 
     In certain embodiments, the light-absorbing material forms a first layer and depositing a second layer of light-absorbing material on the first layer and at least partially over the light-emitting areas of one or more inorganic light emitters to at least partially obscure the light-emitting areas of the one or more inorganic light emitters, and forming optical vias in the second layer over the partially obscured light-emitting areas. 
     In certain embodiments, the method includes disposing one or more pixel controllers on the light-absorbing layer and electrically connecting the pixel controllers to one or more of the inorganic light emitters. 
     In certain embodiments, the light-absorbing material forms a first layer and depositing a second layer of light-absorbing material on the first layer and at least partially over the pixel controllers and electrical connections. 
     In certain embodiments, the light-absorbing material forms a first layer and depositing a second layer of light-absorbing material on the first layer, at least partially over the pixel controllers and electrical connections, and at least partially over the light-emitting areas of one or more inorganic light emitters to at least partially obscure the light-emitting areas of the one or more inorganic light emitters, and forming optical vias in the second layer over the partially obscured light-emitting areas. 
     In certain embodiments, the second layer includes curable light-absorbing materials and comprising recording the locations of the light-emitting areas of the inorganic light emitters and curing the second layers in the non-light-emitting areas to form the optical vias. 
     In certain embodiments, the plurality of inorganic light emitters distributed on the light-absorbing material are at least partially embedded in the light-absorbing material. 
     In certain embodiments, a top surface of each of the plurality of inorganic light emitters are flush with a top surface of the light-absorbing material. 
     In certain embodiments, the plurality of inorganic light emitters are non-native to the display substrate. 
     In certain embodiments, the light-absorbing material is in contract with one or more of the light emitters of the plurality of light emitters. 
     In certain embodiments, the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm. 
     In certain embodiments, the light-absorbing material is contiguous and surrounds the plurality of inorganic light emitters on the display substrate. 
     In certain embodiments, the light-absorbing material is a curable resin that includes a light-absorbing dye or pigment. 
     In certain embodiments, the inorganic light emitters are inorganic light-emitting diodes. 
     In certain embodiments, display substrate has a transparency greater than or equal to 50%, 80%, 90%, or 95% for visible light. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, the display includes a plurality of pixels, each pixel including one or more of the plurality of inorganic light emitters. 
     In certain embodiments, each pixel of the plurality of pixels has inorganic light emitters that emit different colors of light. 
     In certain embodiments, the plurality of light emitters includes: a plurality of red micro inorganic light-emitting diodes, a plurality of green micro inorganic light-emitting diodes, and a plurality of blue micro inorganic light-emitting diodes, wherein each pixel of the plurality of pixels comprises a red micro inorganic light-emitting diode of the plurality of red micro inorganic light-emitting diodes, a green micro inorganic light-emitting diode of the plurality of green micro inorganic light-emitting diodes, and a blue micro inorganic light-emitting diode of the plurality of blue micro inorganic light-emitting diodes. 
     In certain embodiments, the plurality of light emitters comprise a plurality of yellow light emitters, and each pixel of the plurality of pixels comprises a yellow micro inorganic light-emitting diode of the plurality of yellow micro inorganic light-emitting diodes. 
     In certain embodiments, each pixel of the plurality of pixels is spatially separated from two or more adjacent pixels by a first distance, each pixel comprises two or more inorganic light emitters of the plurality of inorganic light emitters, each of the two or more inorganic light emitters within a pixel are spatially separated from an adjacent inorganic light emitter within the pixel by a second distance, and the first distance is greater than the second distance. 
     In certain embodiments, the plurality of pixels forms an array. 
     In certain embodiments, the light-absorbing material is within the spatial area encompassed by the plurality of pixels. 
     In certain embodiments, the display substrate is transparent and the plurality of inorganic light emitters are disposed on the display substrate to emit light through the display substrate. 
     In certain embodiments, the inorganic light emitters emit light in a direction opposite the display substrate. 
     In certain embodiments, each light emitter of the plurality of inorganic light emitters has a light-emissive area and wherein the combined light-emissive areas of the plurality of inorganic light emitters is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, or one ten-thousandth of the light-absorbing material area. 
     In certain embodiments, the plurality of inorganic light emitters are at least partially between the light-absorbing material and the display substrate. 
     In certain embodiments, the light-absorbing material covers display area of the display substrate. 
     In certain embodiments, the display includes electrically conductive wires formed on or over the display substrate and electrically connected to the inorganic light emitters. 
     In certain embodiments, the wires are located between the light-absorbing material and the display substrate and comprising a light filter between the wires and the display substrate. 
     In certain embodiments, the light filter is a dichroic filter. 
     In certain embodiments, the light filter is a black metal, is carbon, or is carbon black. 
     In certain embodiments, the light-absorbing material includes multiple layers of light-absorbing material and the wires are located between the layers. 
     In certain embodiments, the display includes an anti-reflection layer located between the plurality of light emitters and a viewer. 
     In certain embodiments, the light-absorbing material absorbs ambient light transmitted through the display substrate. 
     In certain embodiments, the display substrate is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. 
     In certain embodiments, the display substrate is flexible. 
     In certain embodiments, the display includes a protection layer located between the light emitters and a viewer. 
     In certain embodiments, the display includes a removal layer located on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the method includes forming vias in the light-absorbing material where the light-absorbing material overlaps the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is deposited by spin, curtain, or hopper coating the display substrate with the light-absorbing material. 
     In certain embodiments, the method includes providing a plurality of pixel substrates separate from the display substrate and wherein each of the plurality of inorganic light emitters are located on one of the plurality of pixel substrates and the plurality of pixel substrates are located on the display substrate. 
     In certain embodiments, the pixel substrate includes a material selected from the group consisting of a semiconductor material, plastic, glass, metal, or a combination thereof. 
     In certain embodiments, the common surface on which the plurality of light emitters and the light-absorbing material are formed is a planar surface. 
     In certain embodiments, the display substrate has two opposing smooth sides. 
     In certain embodiments, the display substrate is non-native to the plurality of inorganic light emitters. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method including: providing a plurality of inorganic light emitters; micro transfer printing the plurality of inorganic light emitters onto a handle substrate; depositing a light-absorbing material on the handle substrate such the light-absorbing material covers and surrounds at least a portion of the plurality of inorganic light emitters; and removing the handle substrate. 
     In certain embodiments, the handle substrate is non-native to the plurality of inorganic light emitters. 
     In certain embodiments, the plurality of inorganic light emitters distributed on the light-absorbing material are at least partially embedded in the light-absorbing material. 
     In certain embodiments, a top surface of each of the plurality of inorganic light emitters are flush with a top surface of the light-absorbing material. 
     In certain embodiments, the plurality of inorganic light emitters are non-native to the display substrate. 
     In certain embodiments, the light-absorbing material is in contract with one or more of the light emitters of the plurality of light emitters. 
     In certain embodiments, the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm. 
     In certain embodiments, the light-absorbing material is contiguous and surrounds the plurality of inorganic light emitters on the display substrate. 
     In certain embodiments, the light-absorbing material is a curable resin that includes a light-absorbing dye or pigment. 
     In certain embodiments, the inorganic light emitters are inorganic light-emitting diodes. 
     In certain embodiments, display substrate has a transparency greater than or equal to 50%, 80%, 90%, or 95% for visible light. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, each of the plurality of inorganic light emitters is a light-emitting diode with a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. 
     In certain embodiments, the display includes a plurality of pixels, each pixel including one or more of the plurality of inorganic light emitters. 
     In certain embodiments, each pixel of the plurality of pixels has inorganic light emitters that emit different colors of light. 
     In certain embodiments, the plurality of light emitters includes: a plurality of red micro inorganic light-emitting diodes, a plurality of green micro inorganic light-emitting diodes, and a plurality of blue micro inorganic light-emitting diodes, wherein each pixel of the plurality of pixels comprises a red micro inorganic light-emitting diode of the plurality of red micro inorganic light-emitting diodes, a green micro inorganic light-emitting diode of the plurality of green micro inorganic light-emitting diodes, and a blue micro inorganic light-emitting diode of the plurality of blue micro inorganic light-emitting diodes. 
     In certain embodiments, the plurality of light emitters comprise a plurality of yellow light emitters, and each pixel of the plurality of pixels comprises a yellow micro inorganic light-emitting diode of the plurality of yellow micro inorganic light-emitting diodes. 
     In certain embodiments, each pixel of the plurality of pixels is spatially separated from two or more adjacent pixels by a first distance, each pixel comprises two or more inorganic light emitters of the plurality of inorganic light emitters, each of the two or more inorganic light emitters within a pixel are spatially separated from an adjacent inorganic light emitter within the pixel by a second distance, and the first distance is greater than the second distance. 
     In certain embodiments, the plurality of pixels forms an array. 
     In certain embodiments, the light-absorbing material is within the spatial area encompassed by the plurality of pixels. 
     In certain embodiments, the display substrate is transparent and the plurality of inorganic light emitters are disposed on the display substrate to emit light through the display substrate. 
     In certain embodiments, the inorganic light emitters emit light in a direction opposite the display substrate. 
     In certain embodiments, each light emitter of the plurality of inorganic light emitters has a light-emissive area and wherein the combined light-emissive areas of the plurality of inorganic light emitters is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, or one ten-thousandth of the light-absorbing material area. 
     In certain embodiments, the plurality of inorganic light emitters are at least partially between the light-absorbing material and the display substrate. 
     In certain embodiments, the light-absorbing material covers display area of the display substrate. 
     In certain embodiments, the display includes electrically conductive wires formed on or over the display substrate and electrically connected to the inorganic light emitters. 
     In certain embodiments, the wires are located between the light-absorbing material and the display substrate and comprising a light filter between the wires and the display substrate. 
     In certain embodiments, the light filter is a dichroic filter. 
     In certain embodiments, the light filter is a black metal, is carbon, or is carbon black. 
     In certain embodiments, the light-absorbing material includes multiple layers of light-absorbing material and the wires are located between the layers. 
     In certain embodiments, the display includes an anti-reflection layer located between the plurality of light emitters and a viewer. 
     In certain embodiments, the light-absorbing material absorbs ambient light transmitted through the display substrate. 
     In certain embodiments, the display substrate is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. 
     In certain embodiments, the display substrate is flexible. 
     In certain embodiments, the display includes a protection layer located between the light emitters and a viewer. 
     In certain embodiments, the display includes a removal layer located on a side of the light-absorbing material opposite the display substrate. 
     In certain embodiments, the method includes forming vias in the light-absorbing material where the light-absorbing material overlaps the plurality of light emitters. 
     In certain embodiments, the light-absorbing material is deposited by spin, curtain, or hopper coating the display substrate with the light-absorbing material. 
     In certain embodiments, the method includes providing a plurality of pixel substrates separate from the display substrate and wherein each of the plurality of inorganic light emitters are located on one of the plurality of pixel substrates and the plurality of pixel substrates are located on the display substrate. 
     In certain embodiments, the pixel substrate includes a material selected from the group consisting of a semiconductor material, plastic, glass, metal, or a combination thereof. 
     In certain embodiments, the common surface on which the plurality of light emitters and the light-absorbing material are formed is a planar surface. 
     In certain embodiments, the display substrate has two opposing smooth sides. 
     In certain embodiments, the display substrate is non-native to the plurality of inorganic light emitters. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method includes: providing a plurality of inorganic light emitters; disposing a transparent adhesive layer on a display substrate; micro transfer printing the plurality of inorganic light emitters onto the transparent adhesive layer such that the plurality of inorganic light emitters are spatially separated on the display substrate in a light-emitter layer; and depositing a light-absorbing material on the display substrate in the light-emitter layer and surrounding at least a portion of the plurality of inorganic light emitters, thereby forming a light-absorbing layer on the display substrate. 
     In certain embodiments, the method includes disposing one or more pixel controllers on the light-absorbing layer and electrically connecting the pixel controllers to one or more of the inorganic light emitters. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method including: providing a plurality of inorganic light emitters and one or more pixel controllers; disposing the pixel controllers on a display substrate together with one or more electrical interconnections; micro transfer printing the plurality of inorganic light emitters onto the display substrate and the electrical interconnections such that the plurality of inorganic light emitters are connected to the pixel controllers and are spatially separated on the display substrate in a light-emitter layer; and depositing a light-absorbing material on the display substrate in the light-emitter layer and surrounding at least a portion of the plurality of inorganic light emitters, thereby forming a light-absorbing layer on the display substrate. 
     In certain embodiments, the light-absorbing layer at least partially obscures at least a portion of the light-emitting areas of one or more inorganic light emitters and comprising forming optical vias in the light-absorbing layer. 
     In another aspect, the disclosed technology includes a method of micro assembling a micro light-emitting diode (LED) display, the method including: providing a plurality of inorganic light emitters and one or more pixel controllers; disposing the pixel controllers on a display substrate; micro transfer printing the plurality of inorganic light emitters onto the display substrate such that the plurality of inorganic light emitters are spatially separated on the display substrate in a light-emitter layer; electrically connecting the pixel controllers to the inorganic light emitters; and depositing a light-absorbing material on the display substrate in the light-emitter layer and surrounding at least a portion of the plurality of inorganic light emitters, thereby forming a light-absorbing layer on the display substrate. 
     In certain embodiments, the light-absorbing layer at least partially obscures at least a portion of the light-emitting areas of one or more inorganic light emitters and comprising forming optical vias in the light-absorbing layer. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and other objects, aspects, features, and advantages of the present disclosure will become more apparent and better understood by referring to the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a cross section of an embodiment of the present invention; 
         FIG. 2A  is a plan view and  FIG. 2B  is a perspective of an embodiment of the present invention corresponding to the illustration of  FIG. 1 ; 
         FIG. 3A  is a plan view and  FIG. 3B  is a perspective of another embodiment of the present invention; 
         FIG. 4  is a plan view of an embodiment of the present invention; 
         FIG. 5  is a perspective of a pixel element useful in an embodiment of the present invention; 
         FIG. 6A  is a perspective view and  FIG. 6B  is a cross section of yet another embodiment of the present invention including the pixel element illustrated in  FIG. 5 ; 
         FIG. 7  is a cross section of another embodiment of the present invention; 
         FIGS. 8, 9, and 10  are cross sections of various conductive wire structures in accordance with embodiments of the present invention; 
         FIGS. 11-13  are flow charts illustrating methods of the present invention; and 
         FIG. 14  is a flow chart of a method in accordance with an embodiment of the present invention; 
         FIG. 15  is a cross section of an embodiment of the present invention; 
         FIGS. 16A-16H  are cross sections illustrating steps in constructing an embodiment of the present invention; 
         FIG. 17  is a cross section of an embodiment of the present invention including a patterned removal layer; 
         FIG. 18  is a cross section of yet another embodiment of the present invention including a transparent removal layer; 
         FIG. 19-21  are flow charts illustrating methods of the present invention; 
         FIGS. 22-28  are cross sections of various embodiments of the present invention; 
         FIGS. 29-31  are flow charts illustrating methods of the present invention; 
         FIGS. 32A-32B  are cross section views of another embodiment of the present invention. 
     
    
    
     The features and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The figures are not drawn to scale since the variation in size of various elements in the Figures is too great to permit depiction to scale. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the cross section of  FIG. 1 , the plan view of  FIG. 2A , and the perspective of  FIG. 2B , where the  FIG. 1  cross section is taken along the cross section line A of  FIG. 2B , in an embodiment of the present invention an inorganic-light-emitter display  5  includes a display substrate  10 . A plurality of spatially separated inorganic light emitters  30  are distributed over the display substrate  10  in a light-emitter layer  40 . A light-absorbing material  42  is located over the display substrate  10  in the light-emitter layer  40  and in contact with the inorganic light emitters  30 . The light-absorbing material  42  absorbs transmitted ambient light  64  transmitted through the display substrate  10  without interfering with emitted light  60 . The light emitters  30  can emit different colors of light, for example red light emitters  32  that emit red light, green light emitters  34  that emit green light, and blue light emitters  36  that emit blue light arranged in a regular array of spatially separated pixel elements  20  that each include one of each color light emitter  30 . In some embodiments, more or fewer light emitters are included in each pixel. For example, in addition to light emitters that emit red, green, and blue light, each pixel may include a light emitter than emits yellow light. In an embodiment, referring to  FIG. 2A , the pixel elements  20  are spatially separated by a distance D 1  that is greater than the distance D 2  that separates the light emitters  30  included in a pixel element  20 . 
     The light emitters  30  and the light-absorbing material  42  in the light-emitter layer  40  can be in contact with the display substrate  10  or provided in a layer over or under the display substrate  10 . The display substrate  10  can be transparent, for example transmitting more than 50%, 80%, 90%, or 95% of visible light, and the light emitters  30  can emit light through the display substrate  10  to form a bottom-emitter display. Alternatively, the light emitters  30  can emit light in a direction opposite to the display substrate  10  to form a top-emitter display. 
     The light-emitter layer  40  includes light emitters  30  and the light-absorbing material  42 . In one embodiment, the light emitters  30  and the light-absorbing material  42  are provided on a common surface or substrate, for example display substrate surface  16  on the display substrate  10 . In another embodiment, portions of the light emitters  30  and portions of the light-absorbing material  42  are located in a plane parallel to, or are a common distance from, the display substrate  10 . The light-emitter layer  40  can extend over the entire display substrate  10 , as in  FIG. 1 , or extend over only a portion of the display substrate  10 , as shown in  FIGS. 2A and 2B . In an embodiment, the light-absorbing material  42  forms a contiguous surface, for example surrounding the light emitters  30 . (For clarity of illustration, in  FIGS. 2A and 2B , the light-emitter layer  40  is shown as an area and the light-absorbing material  42  is indicated as a surface on the display substrate  10  but is not shown as a dark layer as in  FIG. 1 .  FIGS. 3A, 3B, and 6B  use a similar illustrative convention.) The light-absorbing material can be located over the entire display substrate  10  or only a portion of the display substrate  10 , for example a display area that includes only the spatial area encompassed by the light emitters  30 . 
     In an embodiment, the light emitters  30  are formed in or located on the display substrate surface  16 . For example, the light emitters  30  are located in a semiconductor layer formed over the extent of the display substrate  10 , for example a layer of semi-crystalline polysilicon. In this embodiment, the components of the light emitters  30  are formed in the semiconductor layer and processed, for example using photolithographic processes, to form the light emitters  30 . Such a structure has the advantage of using conventional photolithographic processes found in the integrated circuit and flat-panel display industries. 
     Alternatively, the light emitters  30  are formed in substrates or on supports separate from the display substrate  10 . For example, the light emitters  30  in some embodiments are separately formed in a semiconductor wafer (e.g., light emitters emitting red light, green light, and blue light, in some embodiments, are each formed on a respective wafer). The light emitters  30  are then removed from the wafer and transferred, for example using micro transfer printing, to the display substrate  10 . This arrangement has the advantage of using a crystalline silicon substrate that provides higher-performance integrated circuit components than can be made in the amorphous or polysilicon semiconductor available on a large substrate such as the display substrate  10 . The display substrate  10 , in some embodiments, is a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, glass, a semiconductor, or sapphire. In this arrangement, the light emitters  30  are small inorganic light-emitting diodes or micro-LEDs. For a discussion of micro-transfer printing techniques see, U.S. Pat. Nos. 8,722,458, 7,622,367 and 8,506,867, each of which is hereby incorporated by reference. 
     In some embodiments, the light-absorbing material  42  in the light-emitting layer  40  is in contact with the inorganic light emitters  30 , for example when the light-absorbing material  42  is in physical contact with the material that emits light, the substrate in which the light emitter  30  is formed, or a package encapsulating the light emitter  30 . For example, an inorganic light-emitting diode light emitter  30  is in contact with the light-absorbing material  42  if the light-absorbing material  42  is in physical contact with a package encapsulating the LED or an LED substrate such as a semiconductor substrate. 
     As shown in  FIG. 2A , the light emitters  30  are each electrically connected to one or more electrically conductive wires  50  that electrically connect two or more of the pixel elements  20  and conduct power, a ground reference voltage, or signals for controlling the pixel elements  20  and the light emitters  30 . In an embodiment, the conductive wires  50  are connected to a display controller  12  that is external to the display substrate  10 . In an alternative embodiment, not shown, the display controller  12  is located on the display substrate  10 . The display controller  12  controls the inorganic-light-emitter display  5  by, for example, providing power, a ground reference signal, and control signals. For clarity of illustration, the conductive wires  50  and the display controller  12  are omitted from the perspective of  FIG. 2B  (and  FIGS. 3B and 6A ). 
     As illustrated in  FIG. 23 , in another embodiment of the present invention, a transparent adhesive layer  15  is located between the display substrate  10  and the plurality of spatially separated inorganic light emitters  30 . The transparent adhesive layer  15  is transparent to visible light or the frequencies of light emitted by the inorganic light emitters  30  and can be 1-100 microns thick. The transparent adhesive layer  15  adheres the spatially separated inorganic light emitters  30  to the display substrate  10  and can maintain the position of the inorganic light emitters  30  during subsequent processing steps, such as coating the light-absorbing material  42 . Suitable adhesives include optical clear adhesives (OCAs), polymers, or curable resins and can be optical-index matched to the display substrate  10  or to an element of the inorganic light emitters  30  (for example a protective or conductive layer over the light-emitting area of the inorganic light emitters  30 ). Index matching reduces reflections and enhances light output and resolution in a display. In a further embodiment, the transparent adhesive layer  15  has a thickness that causes constructive optical interference for one or more of the frequencies of light emitted by the inorganic light emitters  30  or that causes destructive optical interference for at least some frequencies of ambient light. Such a layer thickness can increase light output from the inorganic light emitters  30  and reduces ambient light reflections, thereby increasing the contrast of the device, as discussed with respect to  FIG. 1 . 
     Referring to  FIG. 29 , according to the present invention a method of micro assembling a micro light-emitting diode (LED) display includes providing a plurality of inorganic light emitters  30  in step  105 , providing one or more pixel controller in step  107 , and a display substrate in step  100 . In step  310 , a transparent adhesive layer  15  is disposed on a display substrate  10 , for example by coating a liquid or laminating an adhesive layer with or without a release layer and curing the adhesive. The plurality of inorganic light emitters  30  are micro transfer printed in step  320  onto the transparent adhesive layer  15  so that the plurality of inorganic light emitters  30  are spatially separated on the display substrate  10  in a light-emitter layer  40 . In step  330 , light-absorbing material  42  is deposited, for example by coating or laminating a layer of light-absorbing material  42 , on the display substrate  10  in the light-emitter layer  40 . The light-absorbing material  42  surrounds at least a portion of the plurality of inorganic light emitters  30  to form a light-absorbing layer on the display substrate  10 . 
     Referring to the plan view of  FIG. 3A  and the perspective of  FIG. 3B , in a further embodiment of the inorganic-light-emitter display  5  of the present invention, each pixel element  20  further includes a pixel controller  22 . Each pixel controller  22  is electrically connected to the one or more light emitters  30  (for example the red light emitter  32 , the green light emitter  34 , and the blue light emitter  36 ) in each pixel element  20  and to the display controller  12  through the conductive wires  50  to control the light output of the one or more light emitters  30 . As with the light emitters  30 , the pixel controller  22  can be formed in a semiconductor layer on the display substrate  10  or on or in a separate substrate, such as a semiconductor substrate, and transferred to the display substrate  10 , for example by micro transfer printing. 
     The pixel controller  22  can include power circuitry that is electrically connected to the light emitters  30 . In another embodiment, the pixel controller  22  includes analog, digital, or mixed-signal circuitry. The pixel controller  22  can provide signals through the electrically conductive wires  50  to provide information to the display controller  12  and also can control the light emitters  30  to emit light in an image-wise fashion to provide a display, for example displaying images, graphics, text, or other information. 
       FIG. 4  is a plan view of the top of the inorganic-light-emitter display  5  in the case of a top-emitter structure or is a plan view of the bottom of the organic-light-emitter display  5  in the case of a bottom-emitter structure. As shown, the three-color pixel elements  20  (emitting red, green, and blue light) are spatially separated over the display substrate  10  and surrounded and in contact with a contiguous layer of the light-absorbing material  42  on the display substrate  10 . The light-absorbing material  42  absorbs transmitted ambient light  64  ( FIG. 1 ) illuminating the inorganic-light-emitter display  5  from the emission (viewing) side of the display substrate  10 . 
     As shown in  FIG. 24 , in another embodiment of the present invention, the pixel controllers  22  can be located at least partially over the light-absorbing material  42  and electrically connected to the inorganic light emitters  30  with electrical connections, for example with conductive wires  50  including conductive metals. Metal or metal oxide electrical interconnections can be formed using photolithographic methods and materials. By locating the pixel controllers  22  and conductive wires  50  over the light-absorbing material  42 , ambient light reflections from the pixel controllers  22  and conductive wires  50  are reduced, improving the contrast of the display. Therefore, referring again to  FIG. 29 , in a further embodiment of the present invention, one or more pixel controllers  22  are disposed on the light-absorbing material  42  in step  340  and electrically connected to one or more of the inorganic light emitters  30  in step  350 . 
     Referring next to the perspective of  FIG. 5 , the perspective of  FIG. 6A , and the cross section of  FIG. 6B  taken along the cross section line B of  FIG. 6A , in an alternative embodiment the light emitters  30  and the pixel controller  22  are located on or in a pixel substrate  24  smaller than and separate and distinct from the display substrate  10 . In such an embodiment the display substrate  10  can include material, for example glass or plastic, different from a material in the pixel substrate  24 , for example a semiconductor material such as silicon. In some embodiments, the display substrate  10  and pixel substrate  24  are formed of the same material. In some embodiments, the pixel substrate is glass, plastic, metal, or other such materials (e.g., material non-native to the light emitters). In any of these cases, a pixel substrate  24  that is separate and distinct from the display substrate  10  and that is processed independently from the display substrate  10  to form light emitters  30  is non-native to the display substrate  10 . Likewise, the light emitters  30  formed on or in the pixel substrate  24  are non-native to the display substrate  10 . A further discussion of utilizing pixel substrates in a display can be found in U.S. Patent Application Ser. No. 62/055,472 filed Sep. 25, 2014, entitled Compound Micro-Assembly Strategies and Devices, the contents of which are incorporated by reference herein in its entirety. 
     In one embodiment, the pixel substrate  24  is a semiconductor or includes semiconductor materials and the pixel elements  20  or the pixel controller  22  are formed in the pixel substrate  24 , for example using conventional photolithographic and integrated circuit processing techniques, and the pixel substrate  24  is separately located on the display substrate  10 . Alternatively, as shown in  FIGS. 5, 6A, and 6B , the pixel elements  20  and the pixel controller  22  are formed in separate substrates that are located on the pixel substrate  24  and the pixel substrate  24  is separately located on the display substrate  10 . In such an embodiment, the pixel controller  22  or the light emitters  30  can be formed separately on separate semiconductor substrates, assembled onto the pixel substrate  24 , and then the assembled unit (including the pixel substrate  24 , the light emitters  30  and the pixel controller  22 ) is located on the display substrate surface  16 . This arrangement has the advantage that the pixel elements  20  can be separately tested before they are located on the display substrate surface  16 , thus improving yields and reducing costs. 
     As shown in  FIG. 5 , the light emitters  30  each have a light-emissive area, e.g. red-light-emissive area  32 A, green-light-emissive area  34 A, and blue-light-emissive area  36 A. The light-emissive area of each light emitter  30  can be only a portion of the light emitter  30 . The combined light-emissive area is then the sum of the red-light-emissive area  32 A, green-light-emissive area  34 A, and blue-light-emissive area  36 A. In various embodiments, the combined light-emissive areas of the light emitters  30  is less than or equal to one eighth, one tenth, one twentieth, one fiftieth, one hundredth, one two-hundredth, one five-hundredth, one thousandth, one ten thousandth of the area of the light-absorbing material  42  or the area of the light-emitter layer  40 . 
     In an embodiment of the present invention, the light emitters  30  are micro-light-emitting diodes (micro-LEDs), for example having light-emissive areas of less than 10, 20, 50, or 100 square microns. For example, light emitters  30  can have a height, length, and/or width from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm. Such micro-LEDs have the advantage of a small light-emissive area compared to their brightness as well as color purity providing highly saturated display colors and a substantially Lambertian emission providing a wide viewing angle for the inorganic-light-emitter display  5  of the present invention. A discussion of micro-LEDs and micro-LED displays can be found in U.S. patent application Ser. No. 14/743,981, filed Jun. 18, 2015, entitled Micro Assembled Micro LED Displays and Lighting Elements, which is hereby incorporated by reference in its entirety. 
     Referring to  FIG. 7 , in an embodiment of the inorganic-light-emitter display  5 , the light emitters  30  are at least partially between the light-absorbing material  42  and the display substrate  10 . As shown in  FIG. 7 , the red, green, and blue light emitters  32 ,  34 ,  36  are located on the display substrate  10  and the light-absorbing material  42  in the light-emitter layer  40  extends at least partially over the light emitters  30 . Vias  26  are formed in the light-absorbing material  42  where the light-absorbing material  42  overlaps the light emitters  30  to provide electrical connections to the light emitters  30  for example to the conductive wires  50  (not shown in  FIG. 7 ). 
     The electrically conductive wires  50  electrically connect the light emitters  30  to each other and to sources of power, ground reference voltage, or signals, for example from the display controller  12 . In an embodiment, and as shown in  FIG. 8 , the electrically conductive wires  50  are located or formed on the light-absorbing material  42  over the light-emitter layer  40 . In an alternative embodiment, and as shown in  FIGS. 9 and 10 , the electrically conductive wires  50  are located or formed under the light-absorbing material  42  in the light-emitter layer  40  and on or over the display substrate  10 . In this arrangement, to avoid reflecting transmitted ambient light  64  from the conductive wires  50 , a light filter is located between the conductive wires  50  and the display substrate  10 . The light filter can be an additional light absorber  52  such as a black metal, carbon, carbon black, a black metal, or chromium dioxide or other metal oxides for example as shown in  FIG. 9 , or a dichroic filter  54  as shown in  FIG. 10 . 
     In a further embodiment of the present invention, the light-absorbing material  42  includes multiple layers of light-absorbing material  42  and the conductive wires  50  are located between the layers. For example, a first layer of light-absorbing material  42  is formed, then the conductive wires  50  are formed on the first layer of light-absorbing material  42 , and then a second layer of light-absorbing material  42  is formed over the first layer and the conductive wires  50 . By placing the conductive wires  50  between the layers of light-absorbing material  42 , the conductive wires  50  are rendered less reflective and less visible, reducing the reflectance of the display and improving the display&#39;s contrast. 
     The inorganic-light-emitter display  5  of the present invention can be operated in a variety of useful ways. In one way, the display controller  12  provides power, a ground reference, and control signals to the pixel elements  20  through the electrically conductive wires  50 . The signals can provide a passive-matrix control of the light emitters  30  in the pixel elements. In an alternative embodiment, the pixel elements  20  include the pixel controller  22 . The display controller  12  is connected to the pixel controller  22  through the conductive wires  50  and provides control signals for operating the light emitters  30 . In response to control signals from the display controller  12 , the pixel controllers  22  each control the light emitters  30 , for example in an active-matrix control configuration. Referring again, to  FIG. 1 , in a bottom-emitter embodiment, the light emitters  30  emit light  60  through the display substrate  10  to display information with the inorganic-light-emitter display  5 . An anti-reflection layer  14  or coating absorbs or transmits most, but not all, of the incident ambient light  62  incident on the inorganic-light-emitter display  5 . Transmitted ambient light  64  is absorbed by the light-absorbing material  42 . Although some of the transmitted ambient light  64  can be reflected from the light emitters  30 , the aperture ratio of the inorganic-light-emitter display  5  is so small (for example much less than 1%), that reflected transmitted ambient light  64  is negligible, providing the inorganic-light-emitter display  5  with an excellent contrast ratio, even in bright conditions. Furthermore, a color filter (not shown) can be employed with the light-emitters  30  emitting light of the corresponding color to further absorb ambient light. In the top-emitter case, the anti-reflection layer  14  is located on a display cover opposite the display substrate  10  and the ambient light, incident from the top side of the inorganic-light-emitter display  5 , is absorbed in a similar way. 
     Referring to  FIGS. 1 and 11 , in a method of the present invention, the display substrate  10  is provided in step  100 . The display substrate  10  can be any conventional substrate such as glass, plastic, or metal or include such materials. The display substrate  10  can be transparent, for example having a transmissivity greater than or equal to 50%, 80%, 90%, or 95% for visible light. The display substrate  10  has two opposing smooth sides (such as the display substrate surface  16 ) suitable for material deposition, photolithographic processing, or micro-transfer printing of micro-LEDs. The display substrate  10  can have a size of a conventional display, for example a rectangle with a diagonal length of a few centimeters to one or more meters and a thickness of 50 microns to 10 mm or even more. Such substrates are commercially available. Before, after, or at the same time the light emitters  30  (e.g. micro-LEDs) are provided in step  105 , using conventional photolithographic integrated-circuit processes on semiconductor substrates. The micro-LED semiconductor substrates are much smaller than and separate and distinct from the display substrate  10  and can include different materials. In an alternative method, the controller and micro-LEDs are made in a semiconductor coating formed on the display substrate  10  using conventional substrate processing methods, for example employing low- or high-temperature polysilicon processed, for example with excimer lasers, to form localized crystalline silicon crystals (e.g. LTPS). Likewise, the display controller  12  is made using photolithographic integrated circuit processes on semiconductor substrates, using analog, digital, or mixed-signal circuits. 
     In step  110  the conductive wires  50  are formed on the display substrate  10  using photolithographic and display substrate processing techniques, for example photolithographic processes employing metal or metal oxide deposition using evaporation or sputtering, curable resin coatings (e.g. SU8), positive or negative photo-resist coating, radiation (e.g. ultraviolet radiation) exposure through a patterned mask, and etching methods to form patterned metal structures, vias, insulating layers, and electrical interconnections. The conductive wires  50  can include light-absorbing layers. Inkjet and screen-printing deposition processes and materials can be used to form the patterned conductive wires  50  or other electrical elements. 
     In an embodiment, the light emitters  30  (e.g. micro-LEDs) formed in step  105  are transfer printed to the display substrate  10  in step  120  in one or more transfers. As mentioned above, micro-transfer methods are described in U.S. Pat. Nos. 8,722,458, 7,622,367 and 8,506,867, each of which is hereby incorporated by reference. The light-absorbing material  42  is then deposited in step  130 , for example by coating (e.g. by spin, curtain, or hopper coating) over the display substrate  10  and in contact with the light emitters  30 . The light-absorbing material can include a polymer, resin, acrylic, or curable resin, for example with cross-linking materials and can include light-absorbing particles, pigments, or dyes, for example carbon black, or black metal particles such as chromium dioxide or other metal oxides. If the light-absorbing material  42  includes a curable resin, when cured the resin can adhere the light emitters  30  to the display substrate  10 . In an embodiment and as shown in  FIG. 7 , the light-absorbing material  42  can cover a portion or all of one or more of the light emitters  30 . In an embodiment, the light-absorbing material  42  is patterned, for example using photolithographic patterning methods such as photographically defining or imaging the light-absorbing material  42  and then developing the material. In an alternative technique, the light-absorbing material  42  is not photo-patterned but, since it can be coated after the light elements  30  are located on the display substrate  10  and is therefore formed contiguously around and in contact with the light emitters  30 , the light-absorbing material  42  is patterned without resorting to additional processing steps. 
     The transferred light emitters  30  are then interconnected in step  140  at least partly on the light-absorbing materials  42  using similar materials and methods as in step  110 , for example with the conductive wires  50  and optionally including connection pads and other electrical connection structures, to enable the display controller  12  to electrically interact with the light emitters  30  to emit light in the inorganic-light-emitter display  5 . In alternative processes, the transfer or construction of the light emitters  30  is done before or after all of the conductive wires  50  are in place. Thus, in embodiments the construction of the conductive wires  50  can be done before the light emitters  30  are printed (in step  110  and omitting step  140 ) or after the light emitters  30  are printed (in step  140  and omitting step  110 ), or using both steps  110  and  140 . In any of these cases, the light emitters  30  are electrically connected with the conductive wires  50 , for example through connection pads on the top or bottom of the light emitters  30 . Thus, the light emitters  30  can be completely electrically connected before the light-absorbing materials  42  is deposited or after. 
     In an embodiment, the display controller  12  is externally located (for example on a separate printed circuit board substrate) and electrically connected to the conductive wires  50  using conventional connectors, ribbon cables, or the like. Alternatively, the display controller  12  is affixed to the display substrate  10  outside the area of the light-emitter layer  40  and electrically connected to the conductive wires  50  using conventional wires and buses (not shown), for example using surface mount and soldering technology. 
     Referring to  FIG. 12 , in an alternative process and referring also to  FIGS. 3A and 3B , the pixel controller  22  is provided in step  107 , for example using conventional semiconductor integrated circuit processes, in addition to providing the display substrate  10  (in step  100 ) and providing the light emitters  30  (in step  105 ). The pixel controller  22  can be provided at the same time as, before, or after the micro-LEDs, on separate semiconductor wafers, or on the same semiconductor wafer. In step  122 , the light emitters  30  and the pixel controller  22  are transfer printed to the display substrate  10 , either in a common transfer step or separate transfer steps from the same or different semiconductor wafers. The remaining steps  100 ,  110 ,  130 , and  140  of  FIG. 12  are the same as those described with respect to  FIG. 11 . 
     Referring next to  FIG. 13 , in yet another process and referring also to  FIGS. 5, 6A and 6B , the pixel substrate  24  is provided in step  102  in addition to providing the display substrate  10  (in step  100 ), providing the light emitters  30  (in step  105 ), and providing the pixel controller  22  (in step  107 ). The pixel substrate  24  can, for example, be similar to the display substrate  10  (e.g. made of glass or plastic) but in a much smaller size, for example having an area of 50 square microns, 100 square microns, 500 square microns, or 1 square mm and can be only a few microns thick, for example 5 microns, 10 microns, 20 microns, or 50 microns. The light emitters  30  (e.g. micro-LEDs) and the pixel controller  22  are transfer printed onto the pixel substrate  24  in step  124  using one or more transfers from one or more semiconductor wafers to form the pixel element  20  with the pixel substrate  24  separate from the display substrate  10 , the substrate of the pixel controller  22 , and the substrates of the light emitters  30 . In an alternative embodiment, not shown, the pixel substrate  24  includes a semiconductor and the light emitters  30  and the pixel controller  22  and, optionally, some electrical interconnections, are formed in the pixel substrate  24 . In optional step  142 , electrical interconnects are formed on the pixel substrate  24  to electrically interconnect the light emitters  30  and the pixel controller  22 , for example using the same processes that are employed in steps  110  or  140 . In optional step  125 , the pixel elements  20  on the pixel substrates  24  are tested and accepted, repaired, or discarded. In step  126 , the pixel elements  20  are transfer printed or otherwise assembled onto the display substrate  10  and then electrically interconnected in step  140  with the conductive wires  50  and to connection pads for connection to the display controller  12 . The steps  102  to  107  can be done in any order and before or after any of the steps  100  or  110 . 
     By employing the multi-step transfer or assembly process of  FIG. 13 , increased yields are achieved and thus reduced costs for the inorganic-light-emitter display  5  of the present invention. A further discussion of the multi-step transfer or assembly process can be found in U.S. Patent Application Ser. No. 62/055,472 filed Sep. 25, 2014, entitled Compound Micro-Assembly Strategies and Devices. 
     Referring to  FIG. 14 , the step  110  of forming the conductive wires  50  on the display substrate  10  can include forming a light filter (for example the light absorber  52  or the dichroic filter  54 , as shown in  FIGS. 9 and 10 ) and then constructing the conductive wires  50  over or on the light filter to reduce ambient light reflection from the conductive wires  50 . The conductive wires  50  can be made using various techniques, such as, for example, photolithographic processes. 
     Referring next to  FIG. 15 , in an alternative embodiment of the present invention, the display substrate  10  is located on an opposite side of the light-emitter layer  40  with respect to the direction of light  60  emission and not through the display substrate  10 . In this embodiment, the display substrate  10  can be adhered directly to the light-absorbing material  42  or an additional adhesive layer (not shown) is located between the display substrate  10  and the light-absorbing material  42  to adhere them together. The pixel elements  20  having light emitters  30  including red, green, and blue light-emitters  32 ,  34 ,  36  are as described above with respect to  FIG. 1 . The embodiment of  FIG. 15  has the advantage that a very thin display substrate  10  can be employed. For example, in various embodiments the display substrate  10  is thin glass, a polymer, plastic, resin, polyimide, PEN, PET, metal, metal foil, a semiconductor, or sapphire. Alternatively or in addition, the display substrate  10  is flexible. In some embodiments, the display substrate  10  has a thickness less than or equal to 500 microns, 200 microns, 100 microns, 50 microns, 10 microns, or 5 microns. 
     As shown in  FIGS. 16A-16H  and in  FIG. 19 , the embodiment illustrated in  FIG. 15  is constructed by providing a support substrate  11  in step  200  and as shown in  FIG. 16A . The support substrate  11  can be any substrate with a supporting surface suitable for coating, printing, or processing and can be, for example, glass or plastic. The support substrate  11  is coated in step  210  with a removal layer  18 , for example comprising a removable adhesive or ablation material, as illustrated in  FIG. 16B . Referring next to  FIG. 16C , the red, green, and blue light emitters  32 ,  34 ,  36  making up the pixel elements  20  are located on the removal layer  18  on the support substrate  11 , for example by micro transfer printing as discussed above, in step  220 . As shown in  FIG. 16D , in step  230  light-absorbing material  42  is provided over the light-emitters  30 , the removal layer  18  and support substrate  11 , for example by curtain coating, spin coating, or hopper coating a liquid light-absorbing material over the removal layer  18  and then at least partially drying or curing the liquid light-absorbing material to form the light-absorbing material  42 . In step  240  (not shown) electrical interconnects are patterned over the light-absorbing material  42  to electrically interconnect the red, green, and blue light emitters  32 ,  34 ,  36 , for example using photolithographic processes and materials such as metal. In an alternative method, the interconnection step  240  is done before the light-absorbing material  42  is provided or between layers of the light-absorbing material  42 . 
     Referring to  FIG. 16E , in step  250  the display substrate  10  is attached to the light-absorbing material  42  or to any layers formed on the light-absorbing material  42 . For example, an adhesive layer (not shown) can be provided on the light-absorbing material  42  to adhere the light-absorbing material  42  to the display substrate  10 . Alternatively, the light-absorbing material  42  can be adhesive, in a cured, partially cured, or uncured state, and directly adheres the display substrate  10  to the light-absorbing material  42 . 
     In step  260  and as shown in  FIG. 16F , the support substrate  11  is removed, for example by mechanically peeling the support substrate  11  from the light-absorbing material  42  and light emitters  30 , or by grinding, etching, or polishing. After the support substrate  11  is removed in step  260 , the structure illustrated in  FIG. 16G  (similar to that of  FIG. 15  and reproduced here for clarity) is made. In another embodiment, the removal layer  18  serves as an ablation layer. In such an embodiment the removal layer  18  absorbs light emitted from a light source, for example a laser, is ablated, and releases the light-emitting layer  40  from the support substrate  11 . 
     A protective layer  19  can be applied, for example by adhesion or coating, to the light-absorbing material  42  and light emitters  30 , in step  280  and as shown in  FIG. 16H  and  FIG. 20 . Suitable protective materials can include resins, plastics, scratch-resistant glass, diamond-like coatings, optical hard coats, and the like that are substantially transparent to the light emitted from the light emitters  30 . Alternatively or in addition, optical enhancing elements can be added in step  290  ( FIG. 21 ). Such elements can include dichroic coatings, anti-reflection coatings, refractive elements such as lenslets, or diffractive elements. 
     In an embodiment of the present invention, the removal layer  18  is at least partially removed with the support substrate  11  in step  270  and as shown in  FIGS. 17 and 19 . In the embodiment illustrated in  FIG. 17 , the removal layer  18  is patterned, for example to expose the light emitters  30  and can itself be light absorbing, further improving the contrast of the display. 
     In another, different embodiment the removal layer  18  remains with the light-absorbing material  42  and the light emitters  30  in the light-emitting layer  40  as shown in  FIG. 18 . In this embodiment, the material making up the removal layer  18  can be transparent to the light emitted by the light emitters  30 . The embodiment of the present invention illustrated in  FIG. 15  enables a very thin display substrate  10 , since the construction of the light-emitting layer  40  is done on a temporary support substrate  11  that is subsequently removed from the display structure. This construction process and structure enables ultra-thin, flexible, direct-view, efficient emissive displays that have extremely low reflectivity and are made in a simple and robust process. 
     Referring next to  FIG. 22 , in an alternative embodiment of the present invention, the display substrate  10  is located on an opposite side of the light-emitter layer  40  with respect to the direction of light  60  emission. In this embodiment, the display substrate  10  can be adhered directly to the light-absorbing material  42  or an additional adhesive layer (not shown) is located between the display substrate  10  and the light-absorbing material  42  to adhere them together. The pixel elements  20  having light emitters  30  including red, green, and blue light-emitters  32 ,  34 ,  36  are as described above with respect to  FIG. 1 . In some embodiments, such as the embodiment shown in  FIG. 22 , the light emitters  30  are transferred (e.g., micro-transfer printed) to the light-absorbing material  42  from the native substrate(s) of the light emitters  30 . Since light is not emitted through the substrate  10  but rather in a direction opposite the display substrate  10 , this embodiment is a top-emitter embodiment. 
     As shown in  FIG. 25 , in a further top-emitter embodiment of the present invention, one or more pixel controllers  22  are electrically connected to the inorganic light emitters  30  with conductive wires  50  on the side of the light-absorbing material  42  opposite the display substrate  10 . The light-absorbing material  42  forms a first layer and a second layer of light-absorbing material  42 A is disposed on the first layer, the pixel controllers  22 , and the conductive wires  50 . By locating the pixel controllers  22  and conductive wires  50  between the light-absorbing material  42  and the display substrate  10 , ambient light reflections from the pixel controllers  22  and conductive wires  50  are reduced, improving the contrast of the display. 
     The second layer of light-absorbing material  42 A can be coated. In one embodiment, the relative surface energy of the light-absorbing material  42 A and the inorganic light emitters  30  is such that the second layer of light-absorbing material  42 A does not coat the light-emitting area of the inorganic light emitters  30 . In another embodiment, the second layer of light-absorbing material  42 A is coated over the inorganic light emitters  30  and the second layer of light-absorbing material  42 A is subsequently etched to expose the light-emitting area of the inorganic light emitters  30 . This etch can reduce the entire thickness of the second layer of light-absorbing material  42 A, for example as shown in  FIG. 25 . Alternatively, as shown in  FIG. 26 , the second layer of light-absorbing material  42 A is removed from the light-emitting areas of the inorganic light emitters  30  or from the inorganic light emitters  30 , forming optical vias  28  located at least partially in correspondence with the light-emitting areas of the inorganic light emitters through which light is emitted from the light-emitting areas of the inorganic light emitters  30 . 
     Referring next to  FIG. 30 , in a corresponding method of the present invention light emitters  30  such as micro-LEDs are provided in step  105 , pixel controllers  22  in step  107 , a display substrate  10  is provided in step  100 , and a light-absorbing material  42  layer is disposed on the display substrate  10  in step  410 , for example by coating or laminating with or without a release layer. Light emitters  30 , such as micro-LEDs, are disposed on the light-absorbing material  42 , for example by micro transfer printing, in step  420 , as well as pixel controllers  22  in step  430 . The pixel controllers  22  are electrically connected to the light emitters  30  in step  440 , for example by photolithographically defined metal conductive wires  50 . The light-absorbing material  42  forms a first layer and a second layer of light-absorbing material  42  is disposed on the first layer at least partially between the inorganic light emitters  30  and at least partially over the pixel controllers and electrical connections in step  450 . The light-absorbing material  42  of the second layer can at least partially obscure or occlude the light-emitting areas of the one or more inorganic light emitters  30 . If any light-absorbing material occludes the light-emitting areas of the light emitters  30 , it is removed in step  460 , for example by etching optical vias  28  over the light-emitting areas of the light emitters  30  in the second layer. 
     The second layer of light-absorbing material  42  can include curable materials (for example including ultra-violet-sensitive cross-linking materials or heat-sensitive curable materials). In such an embodiment, in a further method of the present invention, the curable material is cured except where it is exposed, for example by a laser. An image of the light emitters  30  or the light-emitting areas of the light emitters  30  is made before the second layer is disposed over the light emitters  30  and the locations of the light emitters  30  or the light-emitting areas of the light emitters  30  are extracted from the image by image processing. After the second layer of light-absorbing material  42  is disposed over the light emitters  30 , the locations are exposed to light, for example laser light. The curable second layer is then developed and the light-emitting areas of the light emitters  30  are exposed. 
     Alternative top-emitter embodiments are illustrated in  FIG. 27  and  FIG. 28 . As shown in both  FIGS. 27 and 28 , one or more pixel controllers  22  are disposed on the display substrate  10 . In  FIG. 27 , electrical connections such as conductive wires  50  are also formed on the display substrate  10 . The inorganic light emitters  30  are disposed over and electrically connected to the conductive wires  50 . The light-absorbing material  42  is disposed over the pixel controllers  22  and the conductive wires  50  and can be coated or patterned, for example as described with respect to the second layer of light-absorbing material  42 A shown in  FIG. 25  so that the pixel controllers  22  and the electrical connections  50  are located at least partially between the light-absorbing material  42  and the display substrate  10 . As shown in  FIG. 28 , some of the conductive wires  50  are formed over the inorganic light emitters  30 . In these embodiments, optical vias can be formed in the light-absorbing material  42  as described with respect to the second layer of light-absorbing material  42 A shown in  FIG. 26 . This arrangement is useful for inorganic light emitters  30  that emit light through an electrode or have a vertical electrode structure. The structures of  FIGS. 27 and 28  are similar to that of  FIG. 26  except that only a single layer of light-absorbing material  42  is needed, thus reducing the amount of required materials and the number of processing steps. 
     Referring next to  FIG. 31 , in a corresponding method of the present invention light emitters  30  such as micro-LEDs are provided in step  105 , pixel controllers  22  in step  107 , and a display substrate  10  is provided in step  100 . Pixel controllers  22  are disposed on the display substrate  10 , for example by micro transfer printing, in step  510 , and the light emitters  30 , such as micro-LEDs, are disposed on the display substrate  10 , for example by micro transfer printing, in step  520 . The pixel controllers  22  are electrically connected to the light emitters  30  in step  520 , for example by photolithographically defined metal conductive wires  50 . Note that the steps  510  and  520  can be interchanged in other embodiments. For example, the conductive wires  50  can be formed on the display substrate  10  before the light emitters  30  are located on the display substrate  10  (as shown in  FIG. 27 ) or the light emitters  30  are disposed on the display substrate  10  before the conductive wires  50  are formed on the display substrate  10  (as shown in  FIG. 28 ). In the former case, the light emitters  30  are at least partly disposed over the conductive wires  50  (as shown). Similarly, the conductive wires  50  can be made on the display substrate  10  before the pixel controllers  22  are located on the display substrate  10 . Thus, steps  510 ,  520 , and  440  can be performed in various orders depending on the desired structure. Alternatively, conductive wires  50  are formed both before and after the light emitters  30  are disposed on the display substrate  10 . 
     Once the light emitters  30  are connected to the pixel controllers  22 , a layer of light-absorbing material  42  is disposed over the light emitters  30 , the pixel controllers  22 , and interconnecting conductive wires  50 . The light-absorbing material  42  forms a layer of light-absorbing material  42  disposed at least partially between the inorganic light emitters  30  and at least partially over the pixel controllers  22  and electrical connections (conductive wires  50 ) in step  450 . The light-absorbing material  42  of the second layer can at least partially obscure or occlude the light-emitting areas of the one or more inorganic light emitters  30 . If any light-absorbing material occludes the light-emitting areas of the light emitters  30 , it is removed, for example by etching optical vias  28  over the light-emitting areas of the light emitters  30 , in the layer of light-absorbing material  420  in step  460 . 
     In accordance with another embodiment of the present invention, the light-absorbing material  42  in the light-emitter layer  40  is at least partially electrically conductive. Since light-emitting diodes typically include several semiconductor layers that are also electrically conductive, if the electrically conductive light-absorbing material  42  is in contact with the semiconductor layers of the light-emitting diodes, the light-emitting diodes can be prevented from emitting light. To forestall such a problem, according to one embodiment of the present invention, the inorganic light emitters  30  include an electrically insulating layer (e.g., a dielectric layer) formed over the semiconductor layers and disposed between the semiconductor layers and the light-absorbing material  42 . Electrical vias can be formed, as needed, in the electrically insulating layer to provide access to the semiconductor layers of the light-emitting diode. In another embodiment, the light-emitter layer includes an electrically insulating layer, for example over the light-absorbing material  42  and between the inorganic light emitters  30  and the light-absorbing layer  42 . In yet another embodiment, an interlayer dielectric is formed between the inorganic light emitters  30  and the light-absorbing material  42 . 
     In various methods of the present invention, the light emitters  30  are first disposed on the display substrate  10 . If the light emitters  30  include an electrically insulating layer, the light-absorbing material can be coated over and around the light emitters  30 . Electrical vias can be formed in the light-absorbing material  42  and the electrically insulating layer, as needed, for example to make electrical connections to the light emitter  30 . In alternative methods of the present invention, the light-absorbing material  42  is first coated on the display substrate  10 , optical vias are formed in the light-absorbing material  42 , and an electrically insulating layer disposed over the light-absorbing material  42 . The electrically insulating layer can be an interlayer dielectric or can be a sub-layer, together with the light-absorbing material, of the light-emitter layer  40 . The light emitters  30  are then disposed in the optical vias, for example using micro transfer printing, and electrically connected using photolithography. 
     The first of these embodiments is shown, for example in  FIG. 1 . Referring to  FIG. 32A , in an alternative embodiment the light-absorbing material  42  is first deposited on the display substrate  10  and optical vias are formed in the light-absorbing material  42 . Dielectric layer  44  forms an interlayer dielectric over the light-absorbing material  42  and the optical vias into which the light emitters  30  are disposed, for example by micro-transfer printing. In this embodiment, the interlayer dielectric is at least partially transparent to light emitted by the light emitters  30  and is located at least partially between the display substrate  10  and the light-emitters  30 . Referring to  FIG. 32B , in another embodiment, the dielectric layer  44  in the optical via is removed and the light emitters  30  are located on the display substrate and flush with the light-absorbing material  42 . In this case the dielectric layer  44  does not need to be transparent. An adhesive can be employed in the optical via to assist adhesion of the light emitters  30  to the display substrate  10  or dielectric layer  44 . 
     The light-absorbing material  42  can extend beyond the height of the light emitters  30 , can extend to the top of the light-emitters  30  as shown, or extend only partially to the top of the light-emitters  30 . According to embodiments of the present invention, as long as portions of the light emitters  30  and the light-absorbing material  42  are in a common plane, the light-absorbing material is surrounding at least a portion of the inorganic light emitters. 
     As is understood by those skilled in the art, the terms “on,” “over” and “under” are relative terms and can be interchanged in reference to different orientations of the layers, elements, and substrates included in the present invention. For example, a first layer on a second layer, in some implementations means a first layer directly on and in contact with a second layer. In other implementations, a first layer on a second layer includes a first layer and a second layer with another layer therebetween. 
     Having described certain implementations of embodiments, it will now become apparent to one of skill in the art that other implementations incorporating the concepts of the disclosure may be used. Therefore, the invention should not be limited to the described embodiment, but rather should be limited only by the spirit and scope of the following claims. 
     Throughout the description, where apparatus and systems are described as having, including, or comprising specific components, or where processes and methods are described as having, including, or comprising specific steps, it is contemplated that, additionally, there are apparatus, and systems of the disclosed technology that consist essentially of, or consist of, the recited components, and that there are processes and methods according to the disclosed technology that consist essentially of, or consist of, the recited processing steps. 
     It should be understood that the order of steps or order for performing certain action is immaterial so long as the disclosed technology remains operable. Moreover, two or more steps or actions in some circumstances can be conducted simultaneously. The invention has been described in detail with particular reference to certain embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. 
     PARTS LIST 
     
         
         A cross section line 
         B cross section line 
           5  inorganic-light-emitter display 
           10  display substrate 
           11  support substrate 
           12  display controller 
           14  anti-reflection layer 
           15  transparent adhesive layer 
           16  display substrate surface 
           18  removal layer 
           19  protective layer 
           20  pixel element 
           22  pixel controller 
           24  pixel substrate 
           26  via 
           28  optical via 
           30  light emitter 
           32  red light emitter 
           32 A red-light-emissive area 
           34  green light emitter 
           34 A green-light-emissive area 
           36  blue light emitter 
           36 A blue-light-emissive area 
           40  light-emitter layer 
           42  light-absorbing material 
           42 A second layer of light-absorbing material 
           44  dielectric layer 
           50  conductive wire 
           52  light absorber 
           54  dichroic filter 
           60  emitted light 
           62  incident ambient light 
           64  transmitted ambient light 
           100  provide display substrate step 
           102  provide pixel substrate step 
           105  provide light emitters step 
           107  provide pixel controller step 
           110  form wires on substrate step 
           120  print micro-LEDs on display substrate step 
           122  print micro-LEDs and pixel controller on display substrate step 
           124  print micro-LEDs and pixel controller on pixel substrate step 
           125  optional test pixel element step 
           126  print pixel substrate on display substrate step 
           130  form light-absorbing layer on display substrate step 
           140  form interconnects on light-absorbing material step 
           142  optional form interconnects on pixel substrate step 
           200  provide support substrate step 
           210  locate removal layer on support substrate step 
           220  print micro-LEDs on removal layer step 
           230  locate light-absorbing material removal layer step 
           240  form interconnects on light-absorbing material step 
           250  attach display substrate step 
           260  remove support substrate step 
           270  remove portion of removal layer step 
           280  apply protection layer step 
           290  apply optical enhancing elements step 
           310  coat display substrate with optically clear adhesive step 
           320  print micro-LEDs on adhesive layer step 
           330  coat light-absorbing material step 
           340  print pixel controllers on light-absorbing material step 
           350  interconnect pixel controllers to micro-LEDs step 
           410  coat display substrate with light-absorbing material step 
           420  print micro-LEDs on light-absorbing material layer step 
           430  print pixel controllers on light-absorbing material layer step 
           440  interconnect pixel controllers to micro-LEDs step 
           450  coat display substrate, pixel controllers, and micro-LEDs with light-absorbing material step 
           460  remove light-absorbing material from micro-LEDs step 
           510  print pixel controllers on display substrate step 
           520  print micro-LEDs on display substrate step