Light emitting array with continuous active layer and light out-coupling structure

Abstract

A light emitting array includes a semiconductor LED structure, a plurality of decoupling structures, a plurality of separate first electrical contacts, and second electrical contact (s). The LED structure extends continuously over the array. The second electrical contact is in electrical contact with the second semiconductor layer. Each decoupling structure is a protruding portion of the second semiconductor layer. Each first electrical contact includes an external electrode layer opposite a corresponding outcoupling structure. Each outcoupling structure and a corresponding first electrical contact define a corresponding discrete circumscribed pixel region within an adjoining region of the array, each pixel region being separated from other pixel regions. Some of the light emitted in the pixel region is collected or redirected by the out-coupling structure to propagate away from the out-coupling structure and away from the array.

Description

[0001] Priority claim

[0002] This application claims priority to U.S. Provisional Application No. 63 / 433,356, filed on December 16, 2022, in the name of Antonio Lopez Julia, entitled “Light-emitting array with continuous active layer and light outcoupling structures,” which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention generally relates to light emitting diodes and phosphor converted light emitting diodes. Background Art

[0004] Semiconductor light-emitting diodes and laser diodes (collectively referred to herein as "LEDs") are among the most efficient light sources currently available. The emission spectrum of an LED typically exhibits a single, narrow peak at a wavelength determined by the device's structure and the composition of the semiconductor materials from which it is constructed. By appropriately selecting the device structure and material system, LEDs can be designed to operate at ultraviolet, visible, or infrared wavelengths.

[0005] LEDs can be combined with one or more wavelength-converting materials (generally referred to herein as "phosphors") that absorb light emitted by the LED and, in response, emit light of a longer wavelength. For such phosphor-converted LEDs ("pcLEDs"), the fraction of light emitted by the LED that is absorbed by the phosphor depends on the amount of phosphor material in the optical path of the light emitted by the LED, for example, on the concentration of the phosphor material in a phosphor layer disposed on or around the LED and the thickness of the layer.

[0006] Phosphor-converted LEDs can be designed so that all light emitted by the LED is absorbed by one or more phosphors, in which case the emission from the pcLED comes entirely from the phosphors. In this case, for example, the phosphors can be selected to emit light in a narrow spectral region that is not efficiently generated directly by the LED.

[0007] Alternatively, a pcLED can be designed so that only a portion of the light emitted by the LED is absorbed by the phosphor, in which case the emission from the pcLED is a mixture of the light emitted by the LED and the light emitted by the phosphor. By appropriately selecting the LED, phosphor, and phosphor composition, such a pcLED can be designed to emit, for example, white light having a desired color temperature and desired color rendering characteristics.

[0008] Multiple LEDs or pcLEDs can be formed together on a single substrate to form an array. Such an array can be used to form active lighting displays, such as those employed in, for example, smartphones and smartwatches, computer or video displays, augmented or virtual reality displays, or signage; or to form adaptive lighting sources, such as those employed in, for example, motor vehicle headlights, street lighting, camera flash sources, or flashlights (i.e., flashlights). An array having one, a few, or many individual devices per millimeter (e.g., a device pitch or spacing of about one millimeter, a few hundred microns, or less than 100 microns, and a separation of less than 100 microns or only tens of microns or less between adjacent devices) is generally referred to as a miniLED array or microLED array (alternatively, a μLED array). Such a miniLED array or microLED array may also, in many instances, include a phosphor converter as described above; such an array may be referred to as a pc-miniLED array or pc-microLED array. Summary of the Invention

[0009] The semiconductor light emitting array of the present invention includes a semiconductor light emitting diode structure, a plurality of outcoupling structures, a plurality of independent first electrical contacts, and (one or more) second electrical contacts. The diode structure includes a first and a second doped semiconductor layer and a junction or active layer therebetween. The diode structure emits light at a nominal emission vacuum wavelength λ0, which is caused by carrier recombination at the junction or active layer. The first and second semiconductor layers and the junction or active layer extend together over an adjacent area of ​​the array. The second electrical contact is in electrical contact with the second semiconductor layer. Each of the plurality of outcoupling structures includes a protruding portion of the second semiconductor layer that protrudes away from its first surface opposite to the first semiconductor layer. The outcoupling structure collects or redirects at least some of the light emitted by the active layer to leave the outcoupling structure and propagate away from the array. A corresponding external conductive first electrode layer is located on a first surface of the first semiconductor layer opposite to the second semiconductor layer and opposite to each outcoupling structure. The first electrode layer is in electrical contact with the first semiconductor layer at its first surface and forms at least a portion of a corresponding one of the plurality of independent first electrical contacts. Each out-coupling structure and corresponding first electrical contact define a corresponding discrete circumscribed pixel region within a contiguous region of the array, the circumscribed pixel region being isolated from other circumscribed pixel regions of the array.

[0010] Objects and advantages associated with LEDs, pcLEDs, miniLED arrays, pc-miniLED arrays, microLED arrays, and pc-microLED arrays may become apparent when referring to the examples illustrated in the accompanying drawings and disclosed in the following written description or appended claims.

[0011] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic cross-sectional view of an example pcLED is shown.

[0013] Figure 2A and Figure 2B Schematic cross-sectional and top views of an example array of pcLEDs are shown, respectively.

[0014] Figure 3A A schematic cross-sectional view of an example array of pcLEDs arranged relative to a waveguide and projection lens is shown. Figure 3B Shown with Figure 3A A similar arrangement to the one above, but without the waveguide.

[0015] Figure 4A Shown is a schematic top view of an example miniLED or microLED array and a magnified portion of a 3×3 LED of the array. Figure 4B is a side cross-sectional schematic diagram of an example of a close packed array of multicolor phosphor-converted LEDs on a monolithic die and substrate.

[0016] Figure 5A is a schematic top view of a portion of an example LED display in which each display pixel is a red, green, or blue phosphor-converted LED pixel. Figure 5B is a schematic top view of a portion of an example LED display in which each display pixel comprises multiple phosphor-converted LED pixels (red, green, and blue) integrated onto a single die bonded to a control circuit backplane.

[0017] Figure 6A shows a schematic top view of an example electronic board on which a pcLED array may be mounted, and Figure 6B Similarly, the installation Figure 6A An example pcLED array on an electronics board.

[0018] Figure 7A An example camera flash system is schematically shown. Figure 7B An example display system is schematically illustrated. Figure 7C A block diagram of an example visualization system is shown.

[0019] Figure 8 is a schematic cross-sectional view of a light emitting array with an etched active layer.

[0020] Figures 9-21 are schematic cross-sectional views of various examples of light emitting arrays of the present invention, each having an adjoining active layer.

[0021] Figures 22A-22E Various examples of nanostructured optical elements are schematically shown.

[0022] The depicted examples are shown schematically only; all features may not be shown in full detail or to scale; some features or structures may be exaggerated or minimized relative to others, or omitted entirely, for the sake of clarity; and the drawings should not be considered to scale unless explicitly indicated to be so. For example, the vertical dimensions or layer thicknesses of individual LEDs may be exaggerated relative to their lateral extent or relative to substrate or phosphor thickness. The examples shown should not be construed as limiting the scope of the present disclosure or the appended claims. DETAILED DESCRIPTION

[0023] The following detailed description should be read with reference to the accompanying drawings, in which like reference numerals refer to similar elements throughout the different figures. The drawings, which are not necessarily to scale, depict selective examples and are not intended to limit the scope of the subject matter of the present invention. The detailed description illustrates the principles of the subject matter of the present invention by way of example, not by way of limitation. For the purposes of simplicity and clarity, specific embodiments of well-known devices, circuits, and methods may be omitted so as not to obscure the description of the subject matter of the present invention with unnecessary detail.

[0024] Figure 1 An example of a single pcLED 100 is shown, which includes a semiconductor diode structure 102 (collectively referred to herein as an "LED" or "semiconductor LED") disposed on a substrate 104, and a wavelength conversion structure (e.g., a phosphor layer) 106 disposed on the semiconductor LED. The semiconductor diode structure 102 generally includes an active region disposed between an n-type layer and a p-type layer. Applying a suitable forward bias across the diode structure 102 results in light emission from the active region. The wavelength of the emitted light is determined by the composition and structure of the active region.

[0025] The LED can be, for example, a Group III nitride LED that emits blue, violet, or ultraviolet light. LEDs formed from any other suitable material system and emitting light of any other suitable wavelength can also be used. Other suitable material systems can include, for example, Group III phosphide materials, Group III arsenide materials, other binary, ternary, or quaternary alloys of gallium, aluminum, indium, nitrogen, phosphorus, or arsenic, or Group II-VI materials.

[0026] Any suitable phosphor material may be used for or incorporated into the wavelength conversion structure 106 depending on the desired optical output from the pcLED.

[0027] Figure 2A-2B A cross-sectional view and a top view, respectively, of an array 200 of pcLEDs 100 disposed on a substrate 204, each pcLED 100 including a phosphor pixel 106. Such an array can include any suitable number of pcLEDs arranged in any suitable manner. In the illustrated example, the array is depicted as being monolithically formed on a shared substrate, but alternatively, the pcLED array can be formed from separate individual pcLEDs (e.g., singulated devices assembled onto an array substrate). Individual phosphor pixels 106 are shown in the illustrated example, but alternatively, a contiguous layer of phosphor material can be provided across multiple LEDs 102. In some instances, the array 200 can include a light barrier (e.g., reflective, scattering, and / or absorbing) between adjacent LEDs 102, phosphor pixels 106, or both. The substrate 204 can optionally include electrical traces or interconnects, or CMOS or other circuitry for driving the LEDs, and can be formed from any suitable material.

[0028] Optionally, each pcLED 100 may include, or be arranged in combination with, a lens or other optical element positioned adjacent to or disposed on the phosphor layer. Such an optical element (not shown) may be referred to as a "primary optical element." Figure 3A-Figure 3B As shown in , a pcLED array 200 (e.g., mounted on an electronics board) can be arranged in combination with secondary optical elements (such as waveguides, lenses, or both) for use in an intended application. Figure 3A , light emitted by each pcLED 100 of array 200 is collected by a corresponding waveguide 192 and directed to a projection lens 294. For example, projection lens 294 may be a Fresnel lens. For example, this arrangement may be suitable for use in automotive headlights or other adaptive lighting sources. Each pixel may include other primary or secondary optical elements of any suitable type or arrangement, as needed or desired. Figure 3B In FIG. 2 , light emitted by the pcLEDs of array 200 is collected directly by projection lens 294 without the use of an intervening waveguide. This arrangement can be particularly suitable when the pcLEDs can be spaced sufficiently close to each other and can also be used in automotive headlights and camera flash applications or other illumination sources. For example, miniLED or microLED display applications can use Figure 3A-Figure 3BIn general, any suitable arrangement of optical elements (primary, secondary, or both) can be used in combination with the pcLEDs described herein, depending on the desired application.

[0029] although Figure 2A and Figure 2B A 3×3 array of nine pcLEDs is shown, but such an array may include, for example, 10 1 , 10 2 , 10 3 , 10 4 or more LEDs, such as Figure 4A Schematically shown in . Each LED 100 (i.e., pixel) can have a width w1 (e.g., side length) in the plane of the array 200 of, for example, less than or equal to 1 millimeter (mm), less than or equal to 500 microns, less than or equal to 100 microns, or less than or equal to 50 microns. The LEDs 100 in the array 200 can be separated from each other by streets, lanes, or trenches 230 having a width w2 in the plane of the array 200 of, for example, hundreds of microns, less than or equal to 100 microns, less than or equal to 50 microns, less than or equal to 20 microns, less than or equal to 10 microns, or less than or equal to 5 microns. The pixel pitch or spacing D1 is the sum of w1 and w2. Although the illustrated example shows rectangular pixels arranged in a symmetrical matrix, the pixels and array can have any suitable shape or arrangement, whether symmetrical or asymmetrical. Multiple separate LED arrays can be combined in any suitable arrangement in any applicable format to form a larger combined array or display.

[0030] LEDs with a dimension w1 (e.g., side length) in the array plane less than or equal to about 0.10 mm are generally referred to as microLEDs, and an array of such microLEDs may be referred to as a microLED array. LEDs with a dimension w1 (e.g., side length) in the array plane between about 0.10 mm and about 1.0 mm are generally referred to as miniLEDs, and an array of such miniLEDs may be referred to as a miniLED array.

[0031] Figure 4BFIG2 is a schematic cross-sectional view of a close-packed array 200 of multicolor phosphor-converted LEDs 100 on a monolithic die and substrate 204. The side view shows GaN LEDs 102 attached to substrate 204 via metal interconnects 239 (e.g., gold-gold interconnects or solder attached to copper micropillars) and metal interconnects 238. Phosphor pixels 106 are located on or above corresponding GaN LED pixels 102. Either the semiconductor LED pixels 102 or the phosphor pixels 106 (typically both) can be coated on their sides with a reflector or diffuse scattering layer to form an optical isolation barrier 220. In this example, each phosphor pixel 106 is one of three different colors, e.g., a red phosphor pixel 106R, a green phosphor pixel 106G, and a blue phosphor pixel 106B (still generally or collectively referred to as phosphor pixels 106). This arrangement can enable the LED array 200 to be used as a color display.

[0032] The individual LEDs (pixels) in an LED array may be individually addressable, addressable as part of a group or subset of pixels in the array, or may not be addressable. Therefore, luminescent pixel arrays are useful for any application that requires or benefits from fine-grained intensity, spatial, and temporal control of light distribution. These applications may include, but are not limited to, precise, specialized patterning of emitted light from a pixel block or individual pixels, including, in some instances, forming images as a display device. Depending on the application, the emitted light may be spectrally distinct, adaptive over time, and / or environmentally responsive. The luminescent pixel array may provide pre-programmed light distributions in various intensity, spatial, or temporal patterns. The emitted light may be based, at least in part, on received sensor data and may be used for optical wireless communication. The associated electronics and optics may be distinct at the pixel, pixel block, or device level.

[0033] Figure 5A and Figure 5B is an example of an LED array 200 employed in a display application, wherein the LED display comprises a large number of display pixels. In some examples (e.g., Figure 5A In some examples (e.g., as in the example above), each display pixel includes a single semiconductor LED pixel 102 and a corresponding single color (red, green, or blue) phosphor pixel 106R, 106G, or 106B. Each display pixel provides only one of the three colors. Figure 5B), each display pixel includes a plurality of semiconductor LED pixels 102 and a plurality of corresponding phosphor pixels 106 of a plurality of colors. In the example shown, each display pixel includes a 3×3 array of semiconductor pixels 102; three of those LED pixels have red phosphor pixels 106R, three have green phosphor pixels 106G, and three have blue phosphor pixels 106B. Thus, each display pixel can produce any desired color combination. In the example shown, the spatial arrangement of the different colored phosphor pixels 106 varies between display pixels; in some examples (not shown), each display pixel can have the same arrangement of the different colored phosphor pixels 106.

[0034] like Figure 6A and Figure 6B As shown in FIG, pcLED array 200 can be mounted on an electronics board 300 that includes a power and control module 302, a sensor module 304, and an LED attachment area 306. The power and control module 302 can receive power and control signals from an external source and signals from the sensor module 304, and control the operation of the LEDs based on these signals. The sensor module 304 can receive signals from any suitable sensor, such as a temperature or light sensor. Alternatively, the pcLED array 200 can be mounted on a separate board (not shown) from the power and control module and the sensor module.

[0035] An array of independently operable LEDs or pcLEDs can be used in conjunction with a lens, lens system, or other optical device or optical system (e.g., as described above) to provide lighting adapted for a specific purpose. For example, in operation, such an adaptive lighting system can provide lighting that changes color and / or intensity across the illuminated scene or object, and / or is aimed in a desired direction. Focusing or steering the beam of light emitted by the LED or pcLED array can be performed electronically by activating the LEDs or pcLEDs in groups of different sizes or sequentially, allowing for dynamic adjustment of the beam shape and / or direction without moving the optical device or changing the focus of the lens in the lighting device. A controller can be configured to receive data indicating the position and color characteristics of objects or people in the scene, and based on this information, control the LEDs or pcLEDs in the array to provide lighting appropriate for the scene. This data can be provided, for example, by an image sensor, an optical (e.g., laser scanning) sensor, or a non-optical (e.g., millimeter-wave radar) sensor. Such adaptive lighting is becoming increasingly important for automotive applications (e.g., adaptive headlights), mobile device cameras (e.g., adaptive flash), and AR, VR, and MR applications (such as those described below).

[0036] Figure 7AAn example camera flash system 310 is schematically shown that includes an array of LEDs or pcLEDs and an optical (e.g., lens) system 312. The example camera flash system 310 can be or include an adaptive lighting system as described above, in which the LEDs or pcLEDs in the array can be operable individually or in groups. During operation of the camera flash system, illumination from some or all of the LEDs or pcLEDs in the array and optical system 312 can be adjusted (deactivated, operated at full intensity, or operated at intermediate intensities). As described above, the array can be a monolithic array, or include one or more monolithic arrays. As described above, the array can be a micro-LED array.

[0037] The flash system 310 also includes an LED driver 316 controlled by a controller 314 (such as a microprocessor). The controller 314 may also be coupled to a camera 317 and a sensor 318 and operate according to instructions and profiles stored in the memory 311. The camera 317 and the LED or pcLED array and lens system 312 may be controlled by the controller 314 to, for example, match the illumination provided by the system 312 (i.e., the field of view of the illumination system) to the field of view of the camera 317, or otherwise adapt the illumination provided by the system 312 to the scene viewed by the camera as described above. The sensor 318 may include, for example, a position sensor (e.g., a gyroscope and / or accelerometer) and / or other sensors that can be used to determine the position and orientation of the system 310.

[0038] Figure 7BAn example display system 320 is schematically shown and includes an array 321 of individually operable or group-operable LEDs or pcLEDs, a display 322, a light array controller 323, a sensor system 324, and a system controller 325. As described above, the array 321 can be a monolithic array, or include one or more monolithic arrays. The array can be monochrome. Alternatively, the array can be a multicolor array, in which different LEDs or pcLEDs in the array are configured to emit light of different colors, as described above. Thus, the array can be or include a monolithic multicolor matrix of individually operable LED or pcLED light emitters, which can be, for example, microLEDs as described above. A single individually operable LED or pcLED in the array, or a group of adjacent such LEDs or pcLEDs, can correspond to a single pixel (picture element) in the display. For example, a group of three individually operable adjacent LEDs or pcLEDs including a red emitter, a blue emitter, and a green emitter can correspond to a single color-tunable pixel in the display. Similarly, to provide redundancy in the event of a defective LED or pcLED, a group of six individually operable adjacent LEDs or pcLEDs, including two red emitters, two blue emitters, and two green emitters, can correspond to a single color-tunable pixel in a display. Array 321 can be used to project light in a graphic pattern or object pattern, which can, for example, support AR / VR / MR systems. In some cases, individual emitters can be referred to as pixels, even though several emitters operate together to act as a single pixel of a display.

[0039] Sensor input is provided to sensor system 324, while power and user data input is provided to system controller 325. In some embodiments, the modules included in system 320 can be compactly arranged in a single structure, or one or more components can be separately mounted and connected via wireless or wired communication. For example, array 321, display 322, and sensor system 324 can be mounted on a headset or glasses, with the light array controller and / or system controller 325 mounted separately.

[0040] System 320 may incorporate a variety of optics (not shown) to couple the light emitted by array 321 into display 322. Any suitable optics may be used for this purpose.

[0041] Sensor system 324 may include, for example, external sensors to monitor the environment, such as cameras, depth sensors, or audio sensors, and internal sensors to monitor the position of the AR / VR / MR headset, such as accelerometers or two-axis or three-axis gyroscopes. Other sensors may include, but are not limited to, air pressure, strain sensors, temperature sensors, or any other suitable sensors required for local or remote environmental monitoring. In some embodiments, control input through the sensor system may include detected touches or taps, gesture inputs, or controls based on the position of the headset or display.

[0042] In response to data from the sensor system 324, the system controller 325 can send images or instructions to the light array controller 323. Changes or modifications to the images or instructions can also be made through user data input or automatic data input as needed. User data input can include, but is not limited to, data input provided by audio commands, tactile feedback, eye or pupil positioning, or a connected keyboard, mouse, or game controller.

[0043] As described above, AR, VR, and MR systems can be more generally referred to as examples of visualization systems. In a virtual reality system, a display can present a view of a scene (such as a three-dimensional scene) to a user. The user can move within the scene, such as by repositioning the user's head or by walking. The virtual reality system can detect the user's movement and change the view of the scene to account for the movement. For example, when the user rotates the user's head, the system can present a view of the scene that changes in the view direction to match the user's gaze. In this way, the virtual reality system can simulate the user's presence in the three-dimensional scene. In addition, the virtual reality system can receive tactile sensory input, such as from a wearable position sensor, and can optionally provide tactile feedback to the user.

[0044] In an augmented reality system, a display can incorporate elements from the user's surroundings into the view of the scene. For example, an augmented reality system can add text subtitles and / or visual elements to the view of the user's surroundings. For example, a retailer can use an augmented reality system to show a user what a piece of furniture would look like in a room in the user's home by combining a visualization of the furniture on top of a captured image of the user's surroundings. As the user walks around the user's room, the visualization interprets the user's movements and changes the visualization of the furniture in a manner consistent with the movements. For example, an augmented reality system can place a virtual chair in a room. The user can stand in front of the virtual chair's location in the room to view the front of the chair. The user can move within the room to an area behind the virtual chair's location to view the back of the chair. In this way, the augmented reality system can add elements to the dynamic view of the user's surroundings.

[0045] Figure 7C A general block diagram of an example visualization system 330 is shown. The visualization system 330 may include a wearable housing 332, such as a headset or goggles. The housing 332 may mechanically support and house the elements described in detail below. In some examples, one or more of the elements described in detail below may be included in one or more additional housings that may be separate from the wearable housing 332 and may be coupled to the wearable housing 332 wirelessly and / or via a wired connection. For example, a separate housing may reduce the weight of the wearable goggles, such as by including batteries, radios, and other elements. The housing 332 may include one or more batteries 334 that may power any or all of the elements described in detail below. The housing 332 may include circuitry that may be electrically coupled to an external power source (such as a wall outlet) to charge the batteries 334. The housing 332 may include one or more radios 336 for wirelessly communicating with a server or network via a suitable protocol (such as WiFi).

[0046] The visualization system 330 may include one or more sensors 338, such as optical sensors, audio sensors, tactile sensors, thermal sensors, gyroscope sensors, time-of-flight sensors, triangulation-based sensors, and the like. In some examples, the one or more sensors may sense the location, position, and / or orientation of the user. In some examples, the one or more sensors 338 may generate a sensor signal in response to the sensed location, position, and / or orientation. The sensor signal may include sensor data corresponding to the sensed location, position, and / or orientation. For example, the sensor data may include a depth map of the surrounding environment. In some examples, such as for an augmented reality system, the one or more sensors 338 may capture real-time video images of the surrounding environment near the user.

[0047] The visualization system 330 may include one or more video generation processors 340. The one or more video generation processors 340 may receive scene data representing a three-dimensional scene from a server and / or storage medium, such as a set of position coordinates of objects in the scene or a depth map of the scene. The one or more video generation processors 340 may receive one or more sensor signals from one or more sensors 338. In response to the scene data representing the surrounding environment and at least one sensor signal representing the location and / or orientation of the user relative to the surrounding environment, the one or more video generation processors 340 may generate at least one video signal corresponding to a view of the scene. In some examples, the one or more video generation processors 340 may generate two video signals, one for each eye of the user, the two video signals representing views of the scene from the perspective of the user's left eye and right eye, respectively. In some examples, the one or more video generation processors 340 may generate more than two video signals and combine the video signals to provide one video signal for both eyes, two video signals for both eyes, or other combinations.

[0048] Visualization system 330 may include one or more light sources 342 that may provide light for a display of visualization system 330. Suitable light sources 342 may include any of the LEDs, pcLEDs, LED arrays, and pcLED arrays discussed above, such as those discussed above with respect to display system 320.

[0049] The visualization system 330 can include one or more modulators 344. The modulators 344 can be implemented in one of at least two configurations.

[0050] In a first configuration, modulator 344 may include circuitry that can directly modulate light source 342. For example, light source 342 may include an array of light-emitting diodes, and modulator 344 may directly modulate the electrical power, voltage, and / or current directed to each light-emitting diode in the array to form modulated light. Modulation may be performed in an analog and / or digital manner. In some examples, light source 342 may include an array of red light-emitting diodes, an array of green light-emitting diodes, and an array of blue light-emitting diodes, and modulator 344 may directly modulate the red light-emitting diodes, the green light-emitting diodes, and the blue light-emitting diodes to form modulated light to produce a particular image.

[0051] In a second configuration, the modulator 344 may include a modulation panel, such as a liquid crystal panel. The light source 342 may generate uniform or nearly uniform illumination to illuminate the modulation panel. The modulation panel may include pixels. Each pixel may selectively attenuate a corresponding portion of the modulation panel area in response to an electrical modulation signal to form modulated light. In some examples, the modulator 344 may include multiple modulation panels that can modulate light of different colors. For example, the modulator 344 may include a red modulation panel that can attenuate red light from a red light source (such as a red light-emitting diode), a green modulation panel that can attenuate green light from a green light source (such as a green light-emitting diode), and a blue modulation panel that can attenuate blue light from a blue light source (such as a blue light-emitting diode).

[0052] In some examples of the second configuration, the modulator 344 can receive uniform white light or nearly uniform white light from a white light source (such as a white light emitting diode). The modulation panel can include a wavelength selective filter on each pixel of the modulation panel. The panel pixels can be arranged in groups (such as three or four groups), where each group can form a pixel of a color image. For example, each group can include a panel pixel with a red filter, a panel pixel with a green filter, and a panel pixel with a blue filter. Other suitable configurations can also be used.

[0053] The visualization system 330 can include one or more modulation processors 346 that can receive a video signal (such as from one or more video generation processors 340) and, in response, can generate an electrical modulation signal. For configurations in which the modulator 344 directly modulates the light source 342, the electrical modulation signal can drive the light source 342. For configurations in which the modulator 344 includes a modulation panel, the electrical modulation signal can drive the modulation panel.

[0054] The visualization system 330 may include one or more beam combiners 348 (also referred to as beam splitters 348) that may combine light beams of different colors to form a single polychromatic light beam. For configurations in which the light source 342 may include multiple light emitting diodes of different colors, the visualization system 330 may include one or more wavelength-sensitive (e.g., dichroic) beam splitters 348 that may combine light of different colors to form a single polychromatic light beam.

[0055] Visualization system 330 can direct modulated light toward an observer's eyes in one of at least two configurations. In a first configuration, visualization system 330 can function as a projector and can include suitable projection optics 350 that can project the modulated light onto one or more screens 352. Screens 352 can be positioned at a suitable distance from the user's eyes. Visualization system 330 can optionally include one or more lenses 354 that can position a virtual image of screen 352 at a suitable distance from the eyes, such as a close-focus distance of 500 mm, 750 mm, or another suitable distance. In some examples, visualization system 330 can include a single screen 352 so that the modulated light can be directed toward both eyes of the user. In some examples, visualization system 330 can include two screens 352 so that the modulated light from each screen 352 can be directed toward a respective eye of the user. In some examples, visualization system 330 can include more than two screens 352. In a second configuration, visualization system 330 can direct the modulated light directly into one or both eyes of the observer. For example, projection optics 350 may form an image on the retina of one eye of a user, or on the retina of each of both eyes of a user.

[0056] For some configurations of the augmented reality system, visualization system 330 may include an at least partially transparent display, allowing the user to view the user's surroundings through the display. For such configurations, the augmented reality system may generate modulated light corresponding to an enhancement of the surrounding environment, rather than the surrounding environment itself. For example, in an example where a retailer displays chairs, the augmented reality system may direct modulated light corresponding to the chairs, rather than the rest of the room, toward the screen or toward the user's eyes.

[0057] For purposes of the present disclosure and the appended claims, any arrangement in which a layer, surface, substrate, diode structure, or other structure is "on," "over," or "against" another such structure shall encompass arrangements with direct contact between the two structures, as well as arrangements that include some intervening structure therebetween. Conversely, any arrangement in which a layer, surface, substrate, diode structure, or other structure is "directly on," "directly over," or "directly against" another such structure shall encompass only arrangements with direct contact between the two structures. For purposes of the present disclosure and the appended claims, layers, structures, or materials described as "transparent" and "substantially transparent" shall exhibit a sufficiently high level of optical transmission, or a sufficiently low level of optical loss (due to absorption, scattering, or other loss mechanisms), at the nominal emission vacuum wavelength λ0, such that the light emitting device can function within operationally acceptable parameters (e.g., output power or brightness, conversion or extraction efficiency, or other figures of merit (including any parameters described herein)).

[0058] In many previous examples (including some of the examples shown above), multiple individual LED devices 102 (e.g., as shown in FIG. 1 ) are monolithically formed on a common layered semiconductor structure by etching trenches to form mesa-like structures separated by the trenches. Figure 8 Each mesa forms a separate LED device or pixel 102, with a trench extending through at least one (and sometimes both) of the doped semiconductor layers and the junction or active layer therebetween. Figure 8 In the example of , the trench extends completely through the p-type semiconductor layer 102b and the active layer 102a, but only partially through the n-type semiconductor layer 102c. In this common arrangement, the partially etched layer 102c holds the multiple LED devices 102 together in the monolithically integrated array 200. Figure 8 In the example of FIG, a drive current can be directed through each mesa independently of the other mesas via traces 238, contacts 234 and 236, vias 242, and transparent electrodes 244 (where an electrically insulating dielectric layer 240 separates contacts 236 from electrode layer 244). The surrounding trench walls laterally limit the drive current delivered to each mesa, so that the corresponding pixels 102 are independently addressable. However, as pixel size or spacing becomes smaller, many factors limit the light output from each pixel, the contrast between adjacent pixels 102, or both.

[0059] One such factor is the reduced internal quantum efficiency of light emission due to non-radiative carrier recombination at defect sites in the etched sidewalls. Such defects are an unavoidable byproduct of the etching process, and their relative importance increases with decreasing pixel size; as the lateral pixel size decreases, the sidewall perimeter decreases linearly, while the emission area decreases quadratically. For pixel sizes larger than, for example, 50 or 100 μm wide, the effects of recombination at sidewall defects are relatively insignificant, or at least tolerable. As pixel sizes shrink to 20 μm, 10 μm, or even smaller, a larger fraction of the overall carrier recombination is non-radiative recombination at the sidewalls, and the internal quantum efficiency deteriorates accordingly.

[0060] Another factor is that light extraction becomes increasingly difficult as pixel size decreases. A common approach for increasing light extraction from semiconductor LEDs is to provide texturing on the light exit surface of the device. Such texturing can be formed by growing a semiconductor layer on a substrate with corrugations or other similar surface structural features, or by depositing a layer of scattering particles on the light exit surface. However, the resulting structure typically has a feature size of at least a few microns or tens of microns, and therefore cannot be easily implemented on LED pixels that are too small (e.g., less than 5 or 10 μm wide). Even if such a small pixel size is structurally achievable, such light extraction surface features will severely reduce the contrast between adjacent pixels. Figure 8 The common arrangement of the inter-pixel trenches (wherein the inter-pixel trenches extend only partially through one of the semiconductor layers) also allows light emitted from one pixel 102 to propagate into and out of the array from a different pixel 102, as indicated by Figure 8 Indicated by some thick arrows in .

[0061] It would therefore be desirable to provide a light emitting device that exhibits sufficient, desired, or improved internal quantum efficiency or light extraction levels. It would be desirable to provide a monolithic array of LED pixels, including arrays with pixel sizes less than 20 μm, 10 μm, or even 5 μm, while maintaining such internal quantum efficiency or light extraction levels, or sufficient, desired, or improved pixel contrast levels.

[0062] Various examples of the light emitting array 500 of the present invention are Figures 9 to 21Schematically shown in FIG (in cross-section). A corresponding plan view is not shown; the pixels of array 500 can be arranged in any suitable manner; a rectangular array is typically employed. The semiconductor light emitting array 500 of the present invention includes light emitting diode structures 502a / 502b / 502c, a plurality of outcoupling structures 570, a plurality of independent first electrical contacts, and one or more second electrical contacts. The first and second doped semiconductor layers 502b and 502c are respectively arranged to emit light at a nominal emission vacuum wavelength λ0. This emission originates from carrier recombination at the junction between semiconductor layers 502b / 502c or at the active layer 502a. The semiconductor layers 502b / 502c and the junction or active layer 502a extend together over adjacent regions of the array 500. In other words, for most pixels of the array 500, there is no etched edge of the junction or active layer 502a, where defect sites can cause excessive non-radiative recombination.

[0063] In some examples, the first and second semiconductor layers 502b / 502c and the junction or active layer 502a can form a semiconductor light emitting diode (LED) structure. In some examples, the diode structure (i.e., one or more layers 502a / 502b / 502c) can include one or more doped or undoped III-V, II-VI, or IV semiconductor materials or alloys, or mixtures thereof. In some examples, layer 502b can be a p-doped semiconductor layer, and layer 502c can be an n-doped semiconductor layer. In some examples, the junction or active layer 502a can include one or more pn junctions, one or more quantum wells, one or more multiple quantum wells, or one or more quantum dots. In some examples, the nominal emission vacuum wavelength λ0 can be greater than 0.20 μm, greater than 0.4 μm, greater than 0.8 μm, less than 10 μm, less than 2.5 μm, or less than 1.0 μm. In some examples, the total non-zero thickness of the semiconductor layers 502b / 502c and the junction or active layer 502a can be less than 10 μm, less than 5 μm, less than 3 μm, less than 2.0 μm, less than 1.5 μm, or less than 1.0 μm. In some examples, the non-zero thickness of the first semiconductor layer 502b can be less than approximately 1.0 μm, less than approximately 0.8 μm, less than approximately 0.5 μm, or less than approximately 0.3 μm. In some examples, the non-zero thickness of the second semiconductor layer 502c in the region between the outcoupling structures 570 can be less than approximately 1.0 μm, less than approximately 0.8 μm, less than approximately 0.5 μm, or less than approximately 0.3 μm.

[0064] Each of the plurality of outcoupling structures 570 includes a protruding portion of the second semiconductor layer 502c. The outcoupling structures 570 protrude away from the semiconductor layer 502c from a surface opposite the first semiconductor layer 502b. Each outcoupling structure is structurally arranged to collect or redirect at least some of the light emitted by the active layer 502a to exit the outcoupling structure 570 and propagate away from the array 500.

[0065] On a first surface of the first semiconductor layer 502b, opposite the second semiconductor layer 502c and opposite each outcoupling structure 570, is a corresponding external conductive first electrode layer 544. Electrode layer 544, at its first surface, electrically contacts the first semiconductor layer 502b and forms at least a portion of a corresponding one of a plurality of independent first electrical contacts. Each outcoupling structure 570 and the corresponding first electrical contact together define a corresponding discrete external pixel region within a contiguous area of ​​the array 500. Each pixel region is isolated from the other external pixel regions of the array 500. The localized flow of charge carriers confined by the external electrode layer 544 results in localized emission from the active layer 502a; the outcoupling structures 570 are positioned to collect or redirect at least a portion of this localized emission to travel away from the outcoupling structures 570 and away from the array 500. The net effect is that the discrete pixel regions can function as independently operable light-emitting elements of the array 500, despite the lack of physical separation between the corresponding pixel regions of the active layer 502a or the first semiconductor layer 502b. The lack of physical separation between pixel areas (eg, the lack of etched edges of the active layer 502a) reduces the fraction of charge carriers that non-radiatively recombine and therefore cannot generate light.

[0066] In some examples, each outcoupling structure 570 can be arranged with substantially vertical side surfaces (e.g., as in Figure 10 、 Figure 11 、 Figure 13 、 Figure 15 、 Figure 17 、 Figure 19 and Figure 21 In some other examples, each outcoupling structure 570 may be arranged with an inclined side surface, such that the outcoupling structure is tapered (e.g., as in Figure 9 、 Figure 12 、 Figure 14 、 Figure 16 、 Figure 18 and Figure 20). This arrangement can result in improved flux output in some instances. Examples of suitable tapered shapes for the outcoupling structure 570 may include, for example, a truncated cone, a truncated pyramid, a spherical cap or frustum (i.e., a spherical portion), a parabolic cap or frustum, an oblate spherical cap or frustum, an elliptical cap or frustum, or an oval cap or frustum. It should be noted that the figures show side cross-sectional views, and therefore the depicted shapes cannot be definitively determined. Figure 9 、 Figure 12 、 Figure 14 、 Figure 16 、 Figure 18 and Figure 20 An example of an outcoupling structure 570 is depicted, characterized by a single shape that may be a frustoconical or a frustopyramidal shape. Figures 9-21 Examples that may or may not have rotational symmetry are depicted in In some examples, each outcoupling structure 570 can be characterized by a single shape.

[0067] In some examples (not shown), each outcoupling structure 570 can be characterized by a variety of different shapes, such as a first shape at the base of the outcoupling structure 570 at the surface of the semiconductor layer 502c, and a second shape separated from the base by the first shape. In some examples, the first portion of each outcoupling structure 570 near the base has a steeper slope than the second portion separated from the base by the first portion. In some examples, the angular distribution of light emitted from the layer 502a toward the outcoupling structure 570 can be used to guide the arrangement of the outcoupling structure 570. In a specific example, if the angular emission distribution has local maxima at two different angles, the corresponding portions of the outcoupling structure 570 can be arranged (for example, by changing the tilt angle) to redirect the corresponding portions of the angular emission distribution to the corresponding desired directions. Many suitable arrangements can be used.

[0068] In some examples (e.g., as in Figure 12 、 Figure 13 and Figures 16-21 ), each outcoupling structure 570 may include a set of nanostructured scattering elements 556 arranged to redirect at least some of the light emitted by the active layer 502a to exit the outcoupling structure 570 and propagate away from the array 500. Such a set of nanostructured scattering elements 556 can be arranged overall relative to the nominal emission wavelength λ0, for example, to provide non-refractive transmissive redirection of light emitted from the outcoupling structure 570, resulting in a narrowing of the angular distribution of the emission, or to increase the fraction of light emitted from the outcoupling structure 570. Other arrangements of the nanostructured scattering elements 556 may be employed, or the nanostructured scattering elements 556 may be used for other purposes. Suitable structures and materials for the scattering elements 556 are discussed below.

[0069] One or more second electrical contacts provide electrical connections to the semiconductor layer 502c and can be arranged in any suitable manner. Figure 9 、 Figure 10 、 Figure 12 、 Figure 14 、 Figure 16 、 Figure 18 and Figure 20 ), the second electrical contact may include a transparent second electrode layer 574 on the first surface of the second semiconductor layer 502c and the outcoupling structure 570. The transparent second electrode layer 574 may include one or more of indium tin oxide (ITO), indium zinc oxide (IZO), or other suitable transparent conductive oxides (TCOs). In some of these examples (e.g., as in Figure 10 ), the second electrical contact may also include a conductive second contact layer 572 for connecting the second electrode layer 574 to, for example, the conductive trace 238. Although the second contact layer 572 appears discontinuous in the figures (because they are a cross-section of the light-emitting elements), the layer 572 may still be arranged to surround and connect all of the light-emitting elements. In some examples (e.g., as in Figure 10 ), an insulating dielectric layer 573 separates the second contact layer 572 from the side surface of the outcoupling structure 570. In some examples, the second contact layer 572 may include one or more of aluminum, silver, gold, or other suitable metals. In some other examples, there is no transparent second electrode layer (e.g., as in Figure 11 、 Figure 13 、 Figure 15 、 Figure 17 、 Figure 19 and Figure 21 ); the second contact may instead include a second contact layer 572 that electrically contacts the second semiconductor layer 502c only on those portions of its first surface between the plurality of outcoupling structures 570, with an insulating dielectric layer 573 separating the second contact layer 572 from the side surfaces of the outcoupling structures 570. In any example having a metal second contact layer 572 covering those portions of the second semiconductor layer 502c between the outcoupling structures 570, the metal second contact layer 572 may also act as an optical absorber for light propagating between pixel regions and may also prevent light from escaping the second semiconductor layer 502c from those regions, each of which may potentially improve contrast between adjacent pixel regions. The one or more second electrical contacts may be connected to the conductive trace 238 in any suitable manner (e.g., secondary via(s) passing through and electrically insulated from the layers 502b / 502a / 502c, edge contact(s), or peripheral face contact(s)).

[0070] In some examples, the reduced thickness of semiconductor layers 502b and 502c in the region between the outcoupling structures 570 (e.g., a combined thickness of less than 2 microns or less than 1 micron) can improve contrast between adjacent pixel regions. The reduced distance between the first electrode layer 544 and the active layer 502a can reduce the lateral diffusion of charge carriers in the first semiconductor layer 502b before the charge carriers reach the active layer 502a. The reduced thickness of the combined layers reduces the solid angle over which light emitted by the active layer 502a can propagate laterally toward adjacent pixels. In some examples, the first surface of the first semiconductor layer 502b, or the first surface and the second semiconductor layer 502c, or both, can have portions between the pixel regions that are structurally arranged to reduce or prevent propagation of at least some of the emitted light. In some of these examples, one or more optical absorption layers 504 can be located on (i) portions of the first surface of the first semiconductor layer 502b between the pixel regions, or (ii) portions of the first surface of the second semiconductor layer 502c between the pixel regions. The optical absorption layer 504 can be arranged to absorb at least some of the light emitted by the active layer 502a that propagates out of the pixel area through the semiconductor layers. In examples where the second electrical contact is located between the outcoupling structures 570, the optical absorber on the surface of the second semiconductor layer 502c can also act as an ohmic contact layer between the second semiconductor layer 502c and the second contact layer 572.

[0071] For any light that does leave the pixel area, the thin semiconductor layers 502b / 502a / 502c can act as waveguides. Thus, in some examples (e.g., as in Figure 12 In one embodiment, one or more groups of nanostructured scattering elements 506 may be located (i) on a portion of the first surface of the first semiconductor layer 502b between pixel regions, or (ii) on a portion of the first surface of the second semiconductor layer 502c between pixel regions. The nanostructured scattering elements 506 may be arranged to reduce or prevent at least some light emitted from the active layer 502a in one pixel region from propagating through the semiconductor layers 502b / 502a / 502c to adjacent pixel regions. The nanostructured scattering elements 506 may be arranged overall relative to the nominal emission wavelength λ0 to reduce or prevent the propagation of the emitted light in one or more optical modes supported by the semiconductor layers 502b / 502a / 502c. Suitable structures and materials for the scattering elements 506 are discussed below.

[0072] In some examples, each pixel area of ​​the light emitting array 500 may include a transparent electrically insulating dielectric layer 540 and a conductive first contact layer 536. The dielectric layer 540 may be located on the first surface of the first semiconductor layer 502b, opposite to the corresponding outcoupling structure 570. The corresponding first electrode layer 544 may be transparent and located between the first semiconductor layer 502b and the dielectric layer 504, and may include ITO, IZO, or other suitable TCO. The first contact layer 536 may be located on the dielectric layer 540 opposite to the first electrode layer 544, and may include aluminum, silver, gold, or other suitable metal. The first contact layer 536 may be electrically connected to the first electrode layer 544 to form a corresponding independent first electrical contact for the pixel area. In some examples (e.g., as in Figures 9-16 ), the first electrode layer 544 and the first contact layer 536 of each pixel region can be electrically connected through one or more conductive vias 542 passing through the dielectric layer 540. Each via 542 can provide a localized, external electrical connection between the first electrode layer 544 and the corresponding first contact layer 536, and can include aluminum, silver, gold, or other suitable metals.

[0073] In some examples, the corresponding dielectric layer 540 of each pixel region can be in the form of an external dielectric body 540 that protrudes from the first surface of the first semiconductor layer 502b. In some of these examples, the corresponding first electrode layer 544 of each pixel region can be connected to the corresponding first contact layer 536 of the pixel region at the periphery of the dielectric body 540 (e.g., as in Figures 18-21 In some examples (e.g., as in Figures 14-21 ), the dielectric body 540 of each pixel area can have side surfaces that are shaped or tilted to redirect at least some of the light emitted by the active layer 502a and propagating through the first dielectric layer 502b through one or more internal reflections to propagate toward the corresponding outcoupling structure 570. Suitable shapes for the dielectric body 540 can include, for example, a truncated cone, a truncated pyramid, a spherical cap or frustum (i.e., a spherical portion), a parabolic cap or frustum, an oblate spherical cap or frustum, an elliptical cap or frustum, or an oval cap or frustum. It should be noted that the figures show side cross-sectional views and therefore the depicted shapes cannot be definitively determined.

[0074] In some examples (not shown), each dielectric body 540 can be characterized by a variety of different shapes, such as a first shape at the base of the dielectric body 540 at the surface of the semiconductor layer 502b, and a second shape separated from the base by the first shape. In some examples, a first portion of each dielectric body 540 near the base has a steeper slope than a second portion separated from the base by the first portion. In some examples, the angular distribution of light emitted from layer 502a toward the dielectric body 540 can be used to guide the arrangement of the dielectric bodies 540. In a specific example, if the angular emission distribution has local maxima at two different angles, corresponding portions of the dielectric body 540 can be arranged (e.g., by varying the tilt angle) to redirect the corresponding portions of the angular emission distribution in corresponding desired directions toward the outcoupling structure 570. Many suitable arrangements can be employed.

[0075] In some examples, an optical reflector can be located on the dielectric layer 540 opposite the first electrode layer 544. In some examples, the first contact layer 536 can act as an optical reflector. In some examples, a different optical reflector 548 can be located between the dielectric body 540 and the first contact layer 536 (e.g., as in Figure 20 and Figure 21 The optical reflector 548 may be of any suitable type or arrangement, such as a distributed Bragg reflector (DBR) or other multilayer dielectric reflector.

[0076] For each pixel region, some examples may include a dielectric layer 540 located between the dielectric layer 540 and the first surface of the first semiconductor layer 502b (e.g., as in Figures 18-21 502b) or within the dielectric layer 540 (not shown) or a corresponding set of nanostructured scattering elements 552. The nanostructured scattering elements 552 can be arranged to redirect at least some of the light emitted by the active layer 502b that propagates through the dielectric layer 540 to propagate toward the outcoupling structure 570. Suitable structures and materials for the scattering elements 552 are discussed below.

[0077] In some examples, the non-zero spacing of the pixel regions of array 500 can be less than 1.0 mm, less than 0.5 mm, less than 0.3 mm, less than 0.2 mm, less than 0.1 mm, less than 0.08 mm, less than 0.05 mm, less than 0.03 mm, less than 0.02 mm, or less than 0.01 mm. In some examples, the non-zero spacing between adjacent first electrical contacts can be less than 50 μm, less than 20 μm, less than 10 μm, less than 5 μm, less than 2 μm, less than 1.0 μm, or less than 0.05 μm.

[0078] In some examples, array 500 can be arranged so that some or all of its pixel regions act as direct emitters, i.e., light emitted from the junction or active layer 502a serves as the output of those pixel regions. In some examples, array 500 can include one or more wavelength conversion structures (e.g., phosphor wavelength converters) on one or more or all of the pixel regions, so that the output of those pixel regions includes down-converted light emitted by the wavelength conversion structures (with or without residual light emitted by the junction or active layer 502a). In some examples, such wavelength conversion structures can all emit at the same one or more wavelengths; in other examples, the wavelength conversion structures of some pixel regions can emit at a wavelength different from the wavelength emitted by the wavelength conversion structures of some other pixel regions. In some examples, the wavelength conversion structures can be arranged as discrete elements on each pixel region; in some other examples, the wavelength conversion structures can be corresponding regions of an adjacent layer over multiple pixel regions or over all pixel regions.

[0079] The corresponding transparent electrode layers 544 of the plurality of first electrical contacts can be separated from each other by air gaps or by electrically insulating materials so as to substantially prevent direct conduction between adjacent first electrical contacts. In some examples, the corresponding conductive layers 536 of the plurality of first electrical contacts can be separated from each other by air gaps or by electrically insulating materials so as to substantially prevent direct conduction between adjacent first electrical contacts. In some examples, a collection of multiple independent conductive traces or interconnects 238 can be connected to the first electrical contacts (e.g., to layer 536). In some examples, each first electrical contact can be connected to a single corresponding trace or interconnect 238 of the traces or interconnects 238 that is different from the corresponding traces or interconnects 238 connected to any other first electrical contacts. In such examples, each pixel region can be independently addressable.

[0080] In some examples, each dielectric layer or body 540 and each electrically insulating layer 546 or reflector 548 (if present) can include one or more of the following materials: doped or undoped silicon oxide, silicon nitride, or silicon oxynitride; one or more doped or undoped semiconductor oxides, nitrides, or oxynitrides; or one or more doped or undoped metal or transition metal oxides, nitrides, or oxynitrides. In some examples, each insulating layer 540 (or 546, if present) can include an oxidized or otherwise passivated material of the first semiconductor layer 502b; in other examples, each insulating layer or body 540 (or insulating layer 546 or reflector 548, if present) can be formed from a material grown, deposited, or otherwise formed on the semiconductor layer 502b. In some examples, the non-zero thickness of the dielectric layer or body 540 can be less than 10 μm, less than 5 μm, less than 3 μm, less than 2 μm, less than 1.5 μm, or less than 1.0 μm. In some examples, it may be desirable to limit the refractive index contrast between the dielectric layer or body 540 and the semiconductor layer 502b to facilitate collection, collimation, or redirection of emitted light into the dielectric layer or body 540. Thus, in some examples, the difference in refractive index between the first semiconductor layer 502b and the dielectric layer or body 540 can be less than 0.5, less than 0.4, less than 0.3, less than 0.2, or less than 0.1.

[0081] exist Figure 12 、 Figure 13 and Figures 16-21 In the examples of FIG, one or more sets of multiple nanostructured optical elements are depicted that can be used to redirect emitted light within and outside the array 500. In some examples (e.g., as in Figures 18-21 ), the set of multiple nanostructured optical elements 552 can be located between the first semiconductor layer 502b and the dielectric layer or dielectric body 540, or located within the dielectric layer or dielectric body 540. In some examples (e.g., as in Figure 12 、 Figure 13 and Figures 16-21 ), a collection of multiple nanostructured optical elements 556 can be located on the outcoupling structure 570. In some examples (e.g., as in Figure 12), a plurality of sets of nanostructured optical elements 506 can be located on (i) a portion of the first surface of the first semiconductor layer 502b between the pixel regions, or (ii) a portion of the first surface of the second semiconductor layer 502c between the pixel regions, or both. Each such set of nanostructured elements can be arranged as described below, independently of the arrangement of other sets that may be present (e.g., if both element set 552 and element set 556 are present, the arrangement and composition of each set will be independent of the other, except that they will both be referenced to the same nominal output wavelength λ0).

[0082] Each nanostructured optical element 506 / 552 / 556 can be arranged as one or more volumes of dielectric material that protrude into or are embedded in another medium, material, or layer (e.g., the first or second semiconductor layer 502b / 502c, the corresponding dielectric layer or dielectric body 540, or the surrounding medium) and can be characterized by corresponding element dimensions relative to the nominal emission vacuum wavelength λ0 and by element shape. The nanostructured optical elements 506 / 552 / 556 can be arranged into corresponding element arrays characterized by at least one element spacing relative to the nominal emission vacuum wavelength λ0.

[0083] In some examples, each set of nanostructured elements 506 / 552 / 556 may include a large number of protrusions, holes, recesses, inclusions, or structures of suitable sizes and shapes, or they may be arranged into an array of single or dual nanoantennas, partial photonic bandgap structures, photonic crystals, or arrays of metaatoms or metamolecules. Figures 22A-22E Various examples are schematically depicted in FIG. In some examples, the size or spacing of nanostructured elements 506, 552, or 556 can be (i) less than λ0 / n D , less than λ0 / 2n D , less than λ0 / 4n D or less than λ0 / 10n D (n D is the refractive index of the dielectric body 540), (ii) less than λ0 / n SC1 , less than λ0 / 2n SC1 , less than λ0 / 4n SC1 or less than λ0 / 10n SC1 (n SC1 is the refractive index of the first semiconductor layer 502b), or (iii) is less than λ0 / n SC2 , less than λ0 / 2n SC2 , less than λ0 / 4n SC2 or less than λ0 / 10n SC2 (n SC2is the refractive index of the second semiconductor layer 502c). In some examples, the nanostructured elements 506, 552, or 556 may include one or more of the following materials: one or more metals or metal alloys; doped or undoped silicon; one or more doped or undoped III-V, II-VI, or IV semiconductors; doped or undoped silicon oxide, silicon nitride, or silicon oxynitride; one or more doped or undoped metal or transition metal oxides, nitrides, or oxynitrides; one or more doped or undoped semiconductor oxides, nitrides, or oxynitrides; one or more optical glasses; or one or more doped or undoped polymers. In some examples, the nanostructured elements 506, 552, or 556 may be arranged in a periodic array, such as a rectangular, hexagonal, or triangular array. In some examples, the nanostructured elements 506, 552, or 556 may be arranged in an irregular or non-periodic arrangement.

[0084] The arrangement of the first electrode layer 544 and the outcoupling structure 570, and (if present) one or more of the first contact layer 536, the electrically insulating layer 546, or the nanostructured elements 506 / 552 / 556, can be particularly advantageous in that (i) a sufficiently large contrast ratio between adjacent pixel regions, (ii) a sufficiently large fraction of light emitted within a given pixel region exits the array from that pixel region, or (iii) a sufficiently small fraction of light emitted within a given pixel region exits the array from any different pixel region. In some examples, the pixel regions of the array 500 can exhibit a contrast ratio of greater than 5:1, greater than 10:1, greater than 20:1, greater than 50:1, greater than 100:1, or greater than 300:1 to light emitted from adjacent pixel regions. In some examples, the fraction of light emitted within each pixel region that exits the array 500 from that pixel region can be greater than 50%, greater than 75%, greater than 90%, greater than 95%, greater than 98%, or greater than 99%. In some examples, the fraction of light emitted within each pixel region that exits array 500 from any different pixel region may be less than 50%, less than 25%, less than 10%, less than 5%, less than 2%, or less than 1%.

[0085] One or more or all of the diode structure (layers 502a / 502b / 502c), outcoupling structure 570 (size, shape), transparent electrode layer 544, and (if present) dielectric layer or body 540 (size, shape, refractive index), first contact layer 536, through-hole 542, reflector 548, or nanostructured elements 506 / 552 / 556 can be designed or optimized (through calculation, simulation, or iterative design / fabrication / testing of prototype or test devices) based on one or more selected figures of merit (FOMs). FOMs based on device performance that can be considered may include, for example: (i) overall efficiency of light emission relative to input current; (ii) angular distribution of radiant emission of emitted light; (iii) contrast between adjacent pixel areas for light emission, or (iv) other suitable or desired FOMs. Alternatively or in addition, reducing cost or manufacturing complexity can be used as a FOM in the design or optimization process. Optimization for one FOM may result in non-optimal values ​​for one or more other FOMs. Note that a device that is not necessarily fully optimized with respect to any FOM may still provide acceptable improvement in one or more FOMs; such partially optimized devices fall within the scope of the present disclosure or the appended claims.

[0086] In some examples, light emitting array 500 can include a collection of multiple independent conductive traces or interconnects 238 connected to first electrical contacts. In some examples, each first electrical contact can be connected to a single corresponding trace or interconnect 238 of traces or interconnects 238 that is different from the corresponding trace or interconnect 238 connected to at least one other first electrical contact. In some examples, each first electrical contact can be connected to a single corresponding trace or interconnect 238 of traces or interconnects 238 that is different from all corresponding traces or interconnects 238 connected to any other first electrical contact, such that the pixel regions are independently addressable. In some examples, light emitting array 500 can include driver circuitry 302 connected to the first electrical contacts and to second electrical contacts 234 via electrical traces or interconnects 238 through corresponding conductive layers 536. Driver circuitry 302 can be configured and connected to provide an electrical drive current that flows through array 500 and causes array 500 to emit light. The drive circuit can be further constructed and connected so that (i) corresponding portions of the electrical drive current flow as corresponding pixel currents through one or more corresponding pixel regions, and (ii) the magnitude of each pixel current is different from the magnitude of the corresponding pixel current of at least one other pixel region of array 500.

[0087] In some examples, a method for using light emitting array 500 (in any arrangement shown or described) may include selecting a first specified spatial distribution of pixel current amplitudes and operating driver circuitry 302 to provide those pixel current amplitudes to corresponding pixel regions of array 500, thereby causing the array to emit light according to a corresponding first spatial distribution of luminous intensities across array 500. Then, a second specified spatial distribution of pixel current amplitudes that is different from the first spatial distribution may be selected, and driver circuitry 302 may be operated to provide the second specified spatial distribution of pixel current amplitudes to pixel regions of array 500, thereby causing the array to emit light according to a corresponding second spatial distribution of luminous intensities across array 500 that is different from the first spatial distribution of luminous intensities.

[0088] In some examples, a method for manufacturing a light emitting array 500 (in any arrangement shown or described) may include forming a second semiconductor layer 502c on a fabrication substrate (e.g., a sapphire substrate), forming an active layer 502a on the second semiconductor layer 502c, and then forming a first semiconductor layer 502b on the active layer 502a. Any suitable process may be used to grow, deposit, or otherwise form these layers. While still attached to the sapphire substrate, a first electrode layer 544 is formed on the semiconductor layer 502b along with one or more of the dielectric layer 540, nanostructured scattering elements 506 or 552, vias 542, first contact layer 536, or reflector 548 (if present). Any suitable spatially selective material processing technique may be used. After separating the semiconductor layers 502b / 502a / 502c from the sapphire substrate, the entire structure is flipped over for processing the second semiconductor layer 502c to form an outcoupling structure 570, along with (if present) a second contact layer 572, a dielectric element 573, a second electrode layer 574, an absorber 504, or nanostructured scattering elements 506 or 556. Any suitable spatially selective material processing technique may be employed.

[0089] In addition to the foregoing, the following example embodiments fall within the scope of the present disclosure or the appended claims. Any given example below that mentions one or more or all of the foregoing examples should be understood to refer only to those foregoing examples that are not inconsistent with the given example, and to exclude those foregoing examples that are inconsistent with the given example.

[0090] Example 1. A semiconductor light emitting array comprises: first and second doped semiconductor layers arranged to emit light at a nominal emission vacuum wavelength λ0, the nominal emission vacuum wavelength λ0 resulting from carrier recombination at a junction or active layer between the first and second semiconductor layers, the first and second semiconductor layers and the junction or active layer coextensive over a contiguous region of the array; a set of a plurality of outcoupling structures comprising a protruding portion of the second semiconductor layer protruding away from a first surface thereof opposite the first semiconductor layer and structurally arranged to collect or redirect at least some of the light emitted by the active layer to exit the outcoupling structure and propagate away from the array; a corresponding circumscribed conductive first electrode layer on a first surface of the first semiconductor layer opposite the second semiconductor layer and opposite each outcoupling structure, the first electrode layer in electrical contact with the first semiconductor layer at its first surface to form at least a portion of a corresponding one of a plurality of independent first electrical contacts; and one or more second electrical contacts in electrical contact with the second semiconductor layer, each outcoupling structure and the corresponding first electrical contact defining a corresponding discrete circumscribed pixel region within the contiguous region of the array, the circumscribed pixel region being isolated from other circumscribed pixel regions of the array.

[0091] Example 2. The light emitting array according to Example 1, each outcoupling structure is arranged with a substantially vertical side surface.

[0092] Example 3. According to the light emitting array of Example 1, each outcoupling structure is arranged with an inclined side surface so that the outcoupling structure has a tapered shape.

[0093] Example 4. The light emitting array according to Example 3, wherein each dielectric body comprises a truncated cone shape or a truncated pyramid shape.

[0094] Example 5. The light emitting array according to any of Examples 3 or 4, each outcoupling structure comprises a shape of a spherical cap or frustum, a parabolic cap or frustum, an oblate spherical cap or frustum, an elliptical cap or frustum, or an oval cap or frustum.

[0095] Example 6. The light emitting array according to any one of Examples 3 to 5, each outcoupling structure includes a first portion having a first shape and a second portion having a second shape different from the first shape, the first portion being between the second portion and the second semiconductor layer.

[0096] Example 7. The light emitting array of Example 6, the first and second shapes being arranged to transmit or redirect corresponding first and second portions of the angular distribution of light emitted by the active layer to exit the outcoupling structure and propagate away from the array.

[0097] Example 8. The light emitting array according to any one of Examples 1 to 7, wherein each outcoupling structure comprises, over at least a portion thereof, a transparent conductive second electrode layer in electrical contact with the second semiconductor layer, the second electrode layer forming at least a portion of the one or more second electrical contacts.

[0098] Example 9. The light emitting array according to Example 8, wherein the transparent second electrode layer includes one or more of indium tin oxide, indium zinc oxide, one or more other transparent conductive oxides, or a combination or mixture thereof.

[0099] Example 10. The light emitting array according to any one of Examples 1 to 7, wherein the one or more second electrical contacts are in electrical contact with the second semiconductor layer only on those portions of its first surface that are between the plurality of outcoupling structures.

[0100] Example 11. The light emitting array according to any one of Examples 1 to 10, wherein each second electrical contact comprises one or more of aluminum, silver, gold, other metals or metal alloys, or a combination thereof.

[0101] Example 12. The light emitting array according to any one of Examples 1 to 11, wherein each first electrode layer comprises one or more of aluminum, silver, gold, other metals or metal alloys, or a combination thereof.

[0102] Example 13. The light emitting array according to any one of Examples 1 to 11 further includes, for each pixel region: (i) a corresponding electrically insulating transparent dielectric layer on the first surface of the first semiconductor layer opposite to the corresponding out-coupling structure, the corresponding first electrode layer being transparent and located between the first semiconductor layer and the dielectric layer; and (ii) a corresponding electrically conductive first contact layer on the dielectric layer opposite to the first electrode layer and electrically connected to the first electrode layer to form a corresponding independent first electrical contact.

[0103] Example 14. The light emitting array according to Example 13, wherein each transparent first electrode layer comprises one or more of indium tin oxide, indium zinc oxide, one or more other transparent conductive oxides, or a combination or mixture thereof.

[0104] Example 15. The light emitting array according to any of Examples 13 or 14, wherein each dielectric layer comprises one or more of the following materials: doped or undoped silicon oxide, silicon nitride, or silicon oxynitride; one or more doped or undoped semiconductor oxides, nitrides, or oxynitrides; one or more doped or undoped metal or transition metal oxides, nitrides, or oxynitrides; one or more optical glasses; or one or more doped or undoped polymers.

[0105] Example 16. The light emitting array of any of Examples 13 to 15, wherein the non-zero thickness of the dielectric layer is less than 10 μm, less than 5 μm, less than 3 μm, less than 2 μm, less than 1.5 μm, or less than 1 μm.

[0106] Example 17. The light emitting array according to any one of Examples 13 to 16, wherein the corresponding first electrode layer of each pixel region is connected to the corresponding first contact layer of the pixel region via one or more conductive vias passing through the corresponding dielectric layer, each via providing a local external electrical connection between the corresponding first electrode layer and the corresponding first contact layer.

[0107] Example 18. The light emitting array according to any one of Examples 13 to 17, wherein each first contact layer comprises one or more of aluminum, silver, gold, other metals or metal alloys, or a combination thereof.

[0108] Example 19. The light emitting array according to any of Examples 13 to 18, wherein the one or more conductive vias of each first electrical contact include one or more of aluminum, silver, gold, other metals or metal alloys, or a combination thereof.

[0109] Example 20. The light emitting array according to any one of Examples 1 to 19, wherein corresponding first electrical contacts are separated from each other by air gaps or by an electrically insulating material, such that direct electrical conduction between adjacent first electrical contacts is substantially prevented.

[0110] Example 21. The light emitting array according to any one of Examples 13 to 16, wherein the corresponding dielectric layer of each pixel region is a circumscribed dielectric body, and the corresponding first electrode layer of each pixel region is connected to the corresponding first contact layer of the pixel region at the periphery of the dielectric body.

[0111] Example 22. The light emitting array of any one of Examples 13 to 21, wherein the corresponding dielectric layer of each pixel region is an external dielectric body that is structurally arranged to redirect at least some of the light emitted by the active layer that propagates through the dielectric layer to propagate toward the corresponding outcoupling structure.

[0112] Example 23. The light emitting array according to Example 22, wherein each dielectric body comprises a truncated cone shape or a truncated pyramid shape.

[0113] Example 24. The light emitting array of any of Examples 22 or 23, each dielectric body comprising the shape of a spherical cap or frustum, a parabolic cap or frustum, an oblate spherical cap or frustum, an elliptical cap or frustum, or an oval cap or frustum.

[0114] Example 25. The light emitting array according to any one of Examples 22 to 24, wherein each dielectric body includes a first portion having a first shape and a second portion having a second shape different from the first shape, the first portion being between the second portion and the first semiconductor layer.

[0115] Example 26. The light emitting array of Example 25, wherein the first and second shapes are arranged to redirect corresponding first and second portions of the angular distribution of emitted light to propagate in corresponding selected directions, thereby exiting the dielectric body and toward corresponding outcoupling structures.

[0116] Example 27. The light emitting array according to any one of Examples 13 to 26, further comprising, for each pixel region, an optical reflector on the dielectric layer opposite the first electrode layer.

[0117] Example 28. The light emitting array of any of Examples 13 to 27, further comprising a corresponding reflective coating on each dielectric layer between the dielectric layer and the corresponding first contact layer.

[0118] Example 29. The light emitting array according to Example 28, wherein the reflective coating comprises a multilayer reflective coating or a distributed Bragg reflector (DBR).

[0119] Example 30. The light emitting array according to any of Examples 29 or 30, wherein the reflective coating comprises one or more of the following materials: one or more metals or metal alloys; doped or undoped silicon; one or more doped or undoped III-V, II-VI, or IV semiconductors; doped or undoped silicon oxide, silicon nitride, or silicon oxynitride; one or more doped or undoped semiconductor oxides, nitrides, or oxynitrides; one or more doped or undoped metal or transition metal oxides, nitrides, or oxynitrides; one or more optical glasses; or one or more doped or undoped polymers.

[0120] Example 31. The light emitting array according to any one of Examples 1 to 30, wherein the first surface of the first semiconductor layer, or the first surface and the second semiconductor layer, or both, have portions thereof between pixel regions that are structurally arranged to reduce or prevent at least some light emitted from the active layer of one pixel region from propagating through the semiconductor layer to an adjacent pixel region.

[0121] Example 32. The light emitting array according to Example 31 further includes one or more optical absorption layers located (i) on a portion of the first surface of the first semiconductor layer between the pixel regions, or (ii) on a portion of the first surface of the second semiconductor layer between the pixel regions, wherein the one or more optical absorption layers are arranged to absorb at least some of the light emitted by the active layer and propagating through the semiconductor layer out of the corresponding pixel region.

[0122] Example 33. The light emitting array of any of Examples 31 or 32, further comprising one or more groups of nanostructured scattering elements located (i) on a portion of the first surface of the first semiconductor layer between the pixel regions, or (ii) on a portion of the first surface of the second semiconductor layer between the pixel regions, wherein the one or more groups of nanostructured scattering elements are arranged to reduce or prevent at least some light emitted from the active layer of one pixel region from propagating through the semiconductor layer to an adjacent pixel region.

[0123] Example 34. The light emitting array of any of Examples 1 to 33, each outcoupling structure comprising a set of nanostructured scattering elements arranged to redirect at least some of the light emitted by the active layer to exit the outcoupling structure and propagate away from the array.

[0124] Example 35. The light emitting array according to any one of Examples 1 to 34 further includes, for each pixel region, a corresponding set of nanostructured scattering elements located within the dielectric layer or between the dielectric layer and the first semiconductor layer, the nanostructured scattering elements being arranged to redirect at least some of the light emitted by the active layer that propagates through the dielectric layer to propagate toward the outcoupling structure.

[0125] Example 36. The light emitting array according to any one of Examples 33 to 35, wherein any one or more or all of the nanostructured elements in the set of nanostructured elements comprise a plurality of protrusions, holes, recesses, inclusions, ridges, grooves, or structures of appropriate sizes and shapes.

[0126] Example 37. The light emitting array according to any one of Examples 33 to 36, wherein any one or more or all of the nanostructured elements in the group of nanostructured elements comprise an array of single or double nanoantennas, a partial photonic bandgap structure, a photonic crystal, or an array of metaatoms or metamolecules.

[0127] Example 38. The light emitting array according to any one of Examples 33 to 37, wherein the non-zero size or spacing of any one or more or all of the nanostructured elements in the group of nanostructured elements is less than λ0 / n, less than λ0 / 2n, less than λ0 / 4n, or less than λ0 / 10n, where n is the refractive index of the dielectric layer or the first or second semiconductor layer.

[0128] Example 39. The light emitting array according to any one of Examples 33 to 38, wherein any one or more or all of the nanostructured elements in the group of nanostructured elements comprise one or more of the following materials: one or more metals or metal alloys; doped or undoped silicon; one or more doped or undoped III-V, II-VI, or IV semiconductors; doped or undoped silicon oxide, silicon nitride, or silicon oxynitride; one or more doped or undoped metal or transition metal oxides, nitrides, or oxynitrides; one or more doped or undoped semiconductor oxides, nitrides, or oxynitrides; one or more optical glasses; or one or more doped or undoped polymers.

[0129] Example 40. The light emitting array of any one of Examples 1 to 39, wherein the nominal emission vacuum wavelength λ0 is greater than 0.20 μm, greater than 0.4 μm, greater than 0.8 μm, less than 10 μm, less than 2.5 μm, or less than 1.0 μm.

[0130] Example 41. The light emitting array according to any one of Examples 1 to 40, wherein the first and second semiconductor layers and the junction or active layer form a semiconductor light emitting diode structure.

[0131] Example 42. The light emitting array according to any one of Examples 1 to 41, wherein the first and second semiconductor layers include one or more doped or undoped Group III-V, Group II-VI, or Group IV semiconductor materials or alloys or mixtures thereof.

[0132] Example 43. The light emitting array according to any one of Examples 1 to 42, wherein the junction or active layer comprises one or more doped or undoped Group III-V, Group II-VI, or Group IV semiconductor materials or alloys or mixtures thereof.

[0133] Example 44. The light emitting array according to any one of Examples 1 to 43, the junction or active layer comprises one or more pn junctions, one or more quantum wells, one or more multiple quantum wells, or one or more quantum dots.

[0134] Example 45. The light emitting array of any of Examples 1 to 44, wherein a pixel region of the array exhibits a contrast ratio of emitted light exiting from an adjacent pixel region of greater than 5:1, greater than 10:1, greater than 20:1, greater than 50:1, greater than 100:1, or greater than 300:1.

[0135] Example 46. The light emitting array of any of Examples 1 to 45, wherein the non-zero spacing of the pixel regions of the array is less than 1.0 mm, less than 0.5 mm, less than 0.3 mm, less than 0.2 mm, less than 0.10 mm, less than 0.08 mm, less than 0.05 mm, less than 0.03 mm, less than 0.02 mm, or less than 0.010 mm.

[0136] Example 47. The light emitting array of any of Examples 1 to 46, wherein the non-zero spacing between adjacent first electrical contacts is less than 50 μm, less than 20 μm, less than 10 μm, less than 5 μm, less than 2 μm, less than 1 μm, or less than 0.5 μm.

[0137] Example 48. The light emitting array of any of Examples 1 to 47, wherein the non-zero total thickness of the first and second semiconductor layers and the junction or active layer between the outcoupling structure is less than 10 μm, less than 5 μm, less than 3 μm, less than 2 μm, less than 1.5 μm, or less than 1 μm.

[0138] Example 49. The light emitting array of any one of Examples 1 to 48, wherein the pixel regions of the array are arranged such that, of the light emitted at the nominal emission vacuum wavelength λ0 within each pixel region and exiting the array through the second semiconductor layer, at least a specified minimum fraction of the exiting light exits the pixel region, and the specified minimum fraction is greater than 50%, greater than 75%, greater than 90%, greater than 95%, greater than 98%, or greater than 99%.

[0139] Example 50. The light emitting array of any one of Examples 1 to 49, wherein the pixel regions of the array are arranged such that, of the light emitted at the nominal emission vacuum wavelength λ0 within each pixel region and exiting the array through the second semiconductor layer, at most a specified maximum fraction of the exiting light exits the array from other different pixel regions, and the specified maximum fraction is less than 50%, less than 25%, less than 10%, less than 5%, less than 2%, or less than 1%.

[0140] Example 51. The light emitting array of any of Examples 1 to 50, further comprising: a set of a plurality of independent conductive traces or interconnects connected to first electrical contacts, each first electrical contact connected to a single corresponding trace or interconnect of the traces or interconnects that is different from the corresponding trace or interconnect connected to at least one other first electrical contact; and a drive circuit connected to the first and second electrical contacts through the electrical traces or interconnects, the drive circuit being constructed and connected to provide an electrical drive current that flows through the array and causes the array to emit light, and being further constructed and connected such that (i) a corresponding portion of the electrical drive current flows through one or more corresponding pixel regions as a corresponding pixel current, and (ii) the magnitude of each pixel current is different from the magnitude of the corresponding pixel current of at least one other pixel region of the array.

[0141] Example 52. A method for using the light emitting array of Example 51, the method comprising: (A) selecting a first specified spatial distribution of pixel current amplitudes; (B) operating a driver circuit to provide the first specified spatial distribution of pixel current amplitudes to pixel regions of the array, causing the array to emit light according to a corresponding first spatial distribution of luminous intensities across the array; (C) selecting a second specified spatial distribution of pixel current amplitudes that is different from the first specified spatial distribution of pixel current amplitudes; and (D) operating the driver circuit to provide the second specified spatial distribution of pixel current amplitudes to pixel regions of the array, causing the array to emit light according to a corresponding second spatial distribution of luminous intensities across the array, the corresponding second spatial distribution being different from the first spatial distribution of luminous intensities.

[0142] Example 53. A method for manufacturing the light emitting array of Example 51, the method comprising: (A) forming first and second semiconductor layers with a junction or active layer therebetween; (B) forming an outcoupling structure on the second semiconductor layer; (C) forming a first electrical contact in electrical contact with the first semiconductor layer; (D) forming a second electrical contact in electrical contact with the second semiconductor layer; (E) forming one or more electrical traces or interconnects connected to a set of the first and second electrical contacts; and (F) connecting a drive circuit to the first and second electrical contacts using the electrical traces or interconnects.

[0143] Example 54. A method for manufacturing the light emitting array of any of Examples 1 to 51, the method comprising: (A) forming first and second semiconductor layers with a junction or active layer therebetween; (B) forming an outcoupling structure on the second semiconductor layer; (C) forming a first electrical contact in electrical contact with the first semiconductor layer; and (D) forming a second electrical contact in electrical contact with the second semiconductor layer.

[0144] This disclosure is illustrative and not restrictive. Further modifications will be apparent to those skilled in the art in light of this disclosure and are intended to fall within the scope of this disclosure or the appended claims. It is intended that equivalents of the disclosed example embodiments and methods, or modifications thereof, should fall within the scope of this disclosure or the appended claims.

[0145] In the foregoing Detailed Description, various features from several example embodiments may be grouped together for the purpose of streamlining the disclosure. This method of disclosure should not be interpreted as reflecting an intention that any claimed embodiment requires more features than expressly recited in the corresponding claim. Rather, as reflected in the appended claims, inventive subject matter may lie in fewer than all the features of any single disclosed example embodiment. Therefore, this disclosure should be interpreted as implicitly disclosing any embodiment having any suitable subset of one or more features shown, described, or claimed in this application, including those subsets that may not be explicitly disclosed herein. A "suitable" subset of features includes only those features that are neither incompatible nor mutually exclusive with respect to any other features in that subset. The appended claims are hereby incorporated in their entirety into the Detailed Description, with each claim standing on its own as a separately disclosed embodiment. Furthermore, each of the appended dependent claims should be interpreted solely for purposes of disclosure by said incorporation into the Detailed Description, as if written in multiple dependent form and dependent upon all preceding claims that are not inconsistent therewith. It should also be noted that the cumulative scope of the appended claims may, but does not necessarily, encompass all subject matter disclosed in this application.

[0146] The following explanations should apply for the purposes of this disclosure and the appended claims. Unless expressly stated otherwise, the words "include," "comprise," "have," and their variations, wherever they appear, should be understood as open-ended terms, with the same meaning as if a phrase such as "at least" were appended to each instance thereof. The article "a" should be interpreted as "one or more" unless "only one," "single," or other similar limitations are explicitly stated or implied in the particular context; similarly, the article "the" should be interpreted as "one or more of..." unless "only one of...", "single of...", or other similar limitations are explicitly stated or implied in the particular context. The conjunction "or" should be interpreted as inclusive unless: (i) it is explicitly stated otherwise, for example, by using "or...or...", "only one of...", or similar language; or (ii) two or more of the listed alternatives are understood or disclosed (implicitly or explicitly) as being incompatible or mutually exclusive in the particular context. In the latter case, "or" will be understood to cover only those combinations involving non-mutually exclusive alternatives. In one example, each of "a dog or a cat," "one or more dogs or cats," and "one or more dogs or cats" will be interpreted as one or more dogs without any cats, or one or more cats without any dogs, or one or more of each.

[0147] For purposes of this disclosure or the appended claims, when numerical values ​​are recited (with or without terms such as "about," "approximately equal to," "substantially equal to," "greater than about," "less than about," and the like), standard conventions regarding measurement precision, rounding error, and significant figures shall apply unless a different interpretation is expressly stated. With respect to zero quantities described by phrases such as "prevent," "absent," "eliminated," "equal to zero," "negligible," and the like (with or without terms such as "substantially" or "about"), each such phrase shall mean a situation in which the quantity in question has been reduced or minimized to such an extent that, in the context of the intended operation or use of the disclosed or claimed apparatus or method, the overall behavior or performance of the apparatus or method, for practical purposes, is indistinguishable from that which would have occurred if the zero quantity had been substantially completely removed, was exactly equal to zero, or was otherwise exactly zero.

[0148] For purposes of this disclosure and the appended claims, any reference to elements, steps, limitations, or other parts of an embodiment, example, or claim (e.g., first, second, third, etc., (a), (b), (c), etc., or (i), (ii), (iii), etc.) is for clarity purposes only and should not be construed as implying any kind of ordering or priority of the parts so labeled. If any such ordering or priority is intended, it will be explicitly recited in the embodiment, example, or claim, or, in some instances, it will be implicit or inherent based on the specific content of the embodiment, example, or claim. In the appended claims, if it is intended to invoke the provisions of 35 USC §112(f) in an apparatus claim, then the word "means" will appear in the apparatus claim. If it is intended to invoke those provisions in a method claim, then the words "step for..." will appear in the method claim. Conversely, if the words "means" or "step for..." do not appear in a claim, then the provisions of 35 USC §112(f) are not intended to be invoked in respect of that claim.

[0149] If any one or more disclosures are incorporated herein by reference, and such incorporated disclosures conflict with the present disclosure in part or in whole, or differ in scope from the present disclosure, then to the extent of the conflict, the broader disclosure, or broader definition of terms, the present disclosure controls. If such incorporated disclosures conflict with each other in part or in whole, then to the extent of the conflict, the later-dated disclosure controls.

[0150] The Abstract is provided as needed to assist those searching for specific subject matter within the patent document. However, the Abstract is not intended to imply that any particular claim necessarily covers any element, feature, or limitation recited therein. The scope of the subject matter encompassed by each claim should be determined solely by the recitation of that claim.

Claims

1. A semiconductor light emitting array, comprising: a first doped semiconductor layer and a second doped semiconductor layer arranged to emit light at a nominal emission vacuum wavelength λ0 resulting from carrier recombination at a junction or active layer between the first and second semiconductor layers, the first and second semiconductor layers and the junction or active layer coextensive over a contiguous region of the array; a collection of a plurality of outcoupling structures comprising a protruding portion of the second semiconductor layer that protrudes away from a first surface thereof opposite the first semiconductor layer and is structurally arranged to collect or redirect at least some of the light emitted by the active layer to exit the outcoupling structure and propagate away from the array; a corresponding circumscribed conductive first electrode layer on a first surface of the first semiconductor layer opposite the second semiconductor layer and opposite each outcoupling structure, the first electrode layer being in electrical contact with the first semiconductor layer at its first surface so as to form at least a portion of a corresponding one of the plurality of independent first electrical contacts; and one or more second electrical contacts in electrical contact with the second semiconductor layer, Each out-coupling structure and corresponding first electrical contact define a corresponding discrete circumscribed pixel region within a contiguous region of the array, the circumscribed pixel region being isolated from other circumscribed pixel regions of the array. 2 . The light emitting array according to claim 1 , wherein each outcoupling structure is arranged with a substantially vertical side surface. 3 . The light emitting array according to claim 1 , wherein each outcoupling structure is arranged with an inclined side surface so that the outcoupling structure is tapered.

4. The light emitting array of claim 1 , each outcoupling structure comprising a set of nanostructured scattering elements arranged to redirect at least some of the light emitted by the active layer to exit the outcoupling structure and propagate away from the array. 5 . The light emitting array of claim 1 , wherein each outcoupling structure comprises a transparent conductive second electrode layer on at least a portion thereof in electrical contact with the second semiconductor layer, the second electrode layer forming at least a portion of the one or more second electrical contacts. The light emitting array of claim 1 , wherein the one or more second electrical contacts are in electrical contact with the second semiconductor layer only on portions of the first surface thereof that are between the plurality of outcoupling structures.

7. The light emitting array according to claim 1, wherein the first surface of the first semiconductor layer, or the first surface and the second semiconductor layer, or both have portions thereof between pixel regions that are structurally arranged to reduce or prevent at least some light emitted from the active layer of one pixel region from propagating through the semiconductor layer to an adjacent pixel region.

8. The light emitting array of claim 7 , further comprising one or more optical absorption layers, the one or more optical absorption layers being located (i) on a portion of the first surface of the first semiconductor layer between the pixel regions, or (ii) on a portion of the first surface of the second semiconductor layer between the pixel regions, the one or more optical absorption layers being arranged to absorb at least some of the light emitted by the active layer and propagating through the semiconductor layer out of the corresponding pixel region.

9. The light-emitting array of claim 7 , further comprising one or more groups of nanostructured scattering elements, wherein the one or more groups of nanostructured scattering elements are located (i) on a portion of the first surface of the first semiconductor layer between the pixel regions, or (ii) on a portion of the first surface of the second semiconductor layer between the pixel regions, and wherein the one or more groups of nanostructured scattering elements are arranged so as to reduce or prevent at least some light emitted from the active layer of one pixel region from propagating through the semiconductor layer to an adjacent pixel region.

10. The light emitting array of claim 1 , wherein (i) the first semiconductor layer and the second semiconductor layer comprise one or more doped or undoped III-V, II-VI or IV semiconductor materials or alloys or mixtures thereof, and (II) the junction or active layer comprises one or more doped or undoped III-V, II-VI or IV semiconductor materials or alloys or mixtures thereof.

11. The light emitting array of claim 1 , further comprising, for each pixel region: (i) a corresponding electrically insulating transparent dielectric layer on the first surface of the first semiconductor layer opposite to the corresponding out-coupling structure, the corresponding first electrode layer being transparent and located between the first semiconductor layer and the dielectric layer; and (ii) a corresponding electrically conductive first contact layer on the dielectric layer opposite to the first electrode layer and electrically connected to the first electrode layer to form a corresponding independent first electrical contact.

12. The light-emitting array according to claim 11, wherein the corresponding first electrode layer of each pixel region is connected to the corresponding first contact layer of the pixel region via one or more conductive vias passing through the corresponding dielectric layer, and each via provides a local external electrical connection between the corresponding first electrode layer and the corresponding first contact layer. 13 . The light emitting array according to claim 11 , wherein the dielectric layer corresponding to each pixel region is an external dielectric body, and the first electrode layer corresponding to each pixel region is connected to the first contact layer corresponding to the pixel region at the periphery of the dielectric body.

14. The light emitting array of claim 11 , the corresponding dielectric layer of each pixel region being an external dielectric body that is structurally arranged to redirect at least some of the light emitted by the active layer that propagates through the dielectric layer to propagate toward the corresponding outcoupling structure.

15. The light emitting array of claim 11, further comprising, for each pixel region, an optical reflector on the dielectric layer opposite the first electrode layer.

16. The light emitting array of claim 11 , further comprising, for each pixel region, a corresponding set of nanostructured scattering elements located within the dielectric layer or between the dielectric layer and the first semiconductor layer, the nanostructured scattering elements being arranged to redirect at least some of the light emitted by the active layer that propagates through the dielectric layer to propagate toward the outcoupling structure.

17. The light emitting array according to claim 1, further comprising: a collection of a plurality of independent electrically conductive traces or interconnects connected to first electrical contacts, each first electrical contact connected to a single corresponding one of the traces or interconnects that is different from a corresponding trace or interconnect connected to at least one other first electrical contact; and A drive circuit is connected to the first electrical contact and the second electrical contact by electrical traces or interconnects, the drive circuit being constructed and connected to provide an electrical drive current that flows through the array and causes the array to emit light, and is further constructed and connected such that (i) corresponding portions of the electrical drive current flow through one or more corresponding pixel regions as corresponding pixel currents, and (ii) the magnitude of each pixel current is different from the magnitude of the corresponding pixel current of at least one other pixel region of the array.

18. A method for using the light emitting array according to claim 17, the method comprising: (A) selecting a first specified spatial distribution of pixel current amplitude; (B) operating a driver circuit to provide a first specified spatial distribution of pixel current amplitudes to pixel regions of the array, causing the array to emit light according to a corresponding first spatial distribution of luminous intensity across the array; (C) selecting a second specified spatial distribution of pixel current amplitudes that is different from the first specified spatial distribution of pixel current amplitudes; and (D) operating the drive circuit to provide a second specified spatial distribution of pixel current amplitudes to pixel regions of the array, causing the array to emit light according to a corresponding second spatial distribution of luminous intensity across the array, which is different from the first spatial distribution of luminous intensity.

19. A method for manufacturing the light emitting array according to claim 17, the method comprising: (A) forming a first semiconductor layer and a second semiconductor layer with a junction or active layer therebetween; (B) forming an outcoupling structure on the second semiconductor layer; (C) forming a first electrical contact in electrical contact with the first semiconductor layer; (D) forming a second electrical contact in electrical contact with the second semiconductor layer; (E) forming one or more electrical traces or interconnects connected to the set of first and second electrical contacts; and (F) Connecting the drive circuit to the first electrical contact and the second electrical contact using electrical traces or interconnects.

20. A method for manufacturing the light emitting array according to claim 1, the method comprising: (A) forming a first semiconductor layer and a second semiconductor layer with a junction or active layer therebetween; (B) forming an outcoupling structure on the second semiconductor layer; (C) forming a first electrical contact in electrical contact with the first semiconductor layer; and (D) forming a second electrical contact in electrical contact with the second semiconductor layer.

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