Smart Pixel lighting and display microcontroller unit

Abstract

Light-emitting assembly (100), comprising: an arrangement of light-emitting diode (LED) devices (115); and an arrangement of microcontrol units (110) for switching and operating the arrangement of LED devices (115), wherein the arrangement of LED devices (115) and the arrangement of microcontrol units (110) are bonded to the same side of a substrate, the number of microcontrol units (110) in the arrangement of microcontrol units (110) is less than the number of LED devices (115) in the arrangement of LED devices (115), and each microcontrol unit (110) in the arrangement of microcontrol units (110) is in electrical contact with a plurality of pixels comprising the arrangement of LED devices (115); wherein each microcontroller (110) is a microchip and comprises a plurality of microcontroller LED outputs; wherein each plurality of pixels comprises a plurality of groups of LED devices (115) and each microcontroller LED output is coupled to a corresponding group of LED devices (115); and wherein each group of LED devices (115) is coupled in parallel to a corresponding microcontroller LED output.

Description

General state of the art

[0001] The present invention relates to a microcontroller for light-emitting diodes (LEDs). More specifically, embodiments of the present invention relate to an LED microcontroller for use in display or lighting applications. Background information

[0002] Flat panel displays using LED devices are gaining popularity across a wide range of electronic devices, from small handheld electronics to large outdoor displays. High-resolution LED displays, such as those used in modern computer monitors, smartphones, and televisions, typically employ an active-matrix display architecture. In an active-matrix display, each pixel or subpixel has active driver switching logic, enabling precise voltage switching for each pixel, a feature lacking in passive-matrix displays. This precise voltage switching allows for improved image quality and response time compared to passive-matrix displays. In conventional active-matrix displays, the switching logic at each pixel is implemented using a thin-film transistor (TFT) backplane, which drives the emitting elements.A typical switching TFT circuit used in emitting active matrix displays is the 2T1C circuit, which uses two transistors and a capacitor, although more sophisticated TFT circuits are possible.

[0003] The use of a TFT backplane allows for improved precision compared to passive matrix displays; however, the use of a thin-film transistor backplane is not without its drawbacks. High-quality TFT manufacturing is expensive. Due to the high temperatures involved in the manufacturing process, top-quality TFTs require fabrication on a quartz substrate. Lower-temperature processes can be used with a glass substrate, but the resulting transistors may suffer from low charge carrier mobility, reducing their conductivity. Current leakage and power consumption can also become problematic, and uniformity issues can arise at various points during the manufacturing process.

[0004] US 2011 / 0279014A1 describes an electroluminescent device with multiple current-driven pixels arranged in rows and columns such that when current is supplied to a pixel, it produces light; including each pixel with first and second electrodes and current-sensitive electroluminescent media arranged between the first and second electrodes; at least one chiplet less than 20 micrometers thick; including a transistor driver circuit for controlling the operation of at least four pixels, the chiplet being mounted on a substrate and having interconnect pads; a planarization layer arranged over at least a portion of the chiplet; and a first conductive layer over the planarization layer and connected to at least one of the interconnect pads.and a structure for providing electrical signals through the first conductive layer and at least one of the interconnect pads of the chiplet, so that the transistor driver circuit of the chiplet controls the current to the four pixels.

[0005] EP 1 227 468 A2 describes a method for manufacturing a display module, comprising the steps of: providing a substrate; and forming on the substrate, using the same manufacturing process, an image display with an array of addressable display pixels and a pixel driver circuit that responds to control signals and image data to drive the pixels; and a digital signal processing circuit with an input interface through which image data and control signals are received; a frame buffer for storing image data and from which image data is read during a display refresh; a display matrix driver circuit for receiving image data from the frame buffer and supplying control signals to the pixel driver circuit; and a control circuit for coordinating storage, retrieval, and display operations so that the display module is able to refresh the display independently of an external controller.and an image processing circuit to improve the visual perception of the displayed image. Summary of Revelation

[0006] The invention is defined by the independent claim. Preferred embodiments are described by the dependent claims. A smart pixel microcontroller for controlling light-emitting diodes is described. The smart pixel microcontroller can be used to replace the TFT backplane used in LED and LCD display technology and can add new functionality that was previously not possible using thin-film transistors as the switching and operating element in a display. In one embodiment, a light-emitting assembly includes one or more light-emitting diode (LED) devices and one or more microcontrollers for switching and operating the one or more LED devices. The one or more LED devices and the one or more microcontrollers are bonded to the same side of a substrate.In one embodiment, an LED device and a microcontrol unit are bonded to the substrate with a material such as indium, gold, silver, copper or their alloys.

[0007] In one embodiment, the integrated smart pixel circuit is configured for analog inputs and has an input block and an output block containing electronics. In such an embodiment, the smart pixel microcontroller is controlled by a voltage applied to scanning and data lines, similar to an active-matrix display. In analog form, the smart pixel microcontroller can receive at least one analog data input to control at least one LED device, although multiple LED devices can be controlled by a single microcontroller. In another embodiment, the smart pixel microcontroller supplements analog switching logic with digital storage to enable adaptive update frequencies and display self-refresh. In yet another embodiment, capacitive storage is used to store analog inputs.

[0008] In one embodiment, the smart pixel microcontroller is configured for digital inputs and comprises an input block and an output block containing digital logic, and a memory module with embedded memory. Digital inputs can be received via a digital bus or a point-to-point data link. Multiple LED devices or sensor devices can be controlled by a single microcontroller. In one embodiment, adaptive display update frequencies are enabled by storing data in each integrated circuit.

[0009] In one embodiment, a plurality of LED devices are bonded to the same side of the substrate as the microcontroller and are electrically connected to the microcontroller. The LED devices can be used as subpixels in a display and can be arranged in a red-green-blue (RGB) subpixel array. Other subpixel arrays and schemes are also possible. In one embodiment, the light-emitting assembly includes an array of LED devices and an array of microcontrollers bonded to the same side of the substrate. The number of microcontrollers in the array of microcontrollers is less than the number of LED devices in the array of LED devices. In one embodiment, each microcontroller is electrically connected to a plurality of pixels to drive a plurality of LED devices in each pixel.

[0010] In addition to controlling the display's emitting elements, the microcontroller can be coupled with one or more optical, electrical, or thermal sensors. Alternatively, the microcontroller can include one or more sensors. In one embodiment, the smart pixel microcontroller is coupled with one or more pressure sensors, which can be used to provide visual feedback on a display when it is touched or to transmit user input on a touch-sensitive display. In another embodiment, sensors can be used to detect drift in the display's white point over time, and the display can be recalibrated periodically to maintain a consistent white point.

[0011] An embodiment of a method for fabricating a display or illumination device using a receiving substrate, one or more transmission heads, and one or more support substrates is also disclosed. The illumination or display device can be fabricated by placing a microscale subpixel array onto a receiving substrate, the receiving substrate being prepared with distribution lines to couple the components of the microscale subpixel array. In one embodiment, a method for fabricating a light-emitting assembly includes positioning an array of transmission heads over a substrate supporting a plurality of LED devices, picking up the plurality of LED devices, and placing the plurality of LED devices onto a receiving substrate.This process can be repeated for a separate substrate carrying a different plurality of LED devices with, for example, different light emission characteristics. The same or a different arrangement of transfer heads can be used. The same or a different arrangement of transfer heads is then positioned over a substrate carrying a plurality of microcontrollers, receiving the plurality of microcontrollers and placing the microcontrollers on the same side of the receiving substrate as the plurality of LED devices. According to embodiments of the invention, the arrangements of transfer heads can operate according to electrostatic principles. The plurality of LED devices and microcontrollers can also be bonded to the receiving substrate.In one embodiment, bonding is achieved by heating the multitude of LED devices and the multitude of microcontrollers with the corresponding arrangement of transfer heads. Bonding can also be achieved by thermocompression bonding with the arrangement of transfer heads. Additionally, one or more sensor devices can also be placed on the receiving substrate using an electrostatic transfer head.

[0012] The foregoing summary does not constitute an exhaustive list of all aspects to be explained. It is understood that the details detailed below encompass all systems and procedures that can be executed by any suitable combination of the diverse aspects summarized above. Brief description of the drawings

[0013] Embodiments are illustrated in an exemplary and non-limiting manner in the figures of the accompanying drawings, in which: Fig. 1 shows a circuit diagram of a smart pixel micromatrix according to one embodiment; Fig. 2 shows a block diagram of a smart pixel microcontroller structure according to one embodiment; Fig. Figure 3 shows a block diagram of an alternative smart pixel microcontroller structure according to one embodiment; Fig. Figure 4 shows a block diagram of an input block of a smart pixel microcontroller input block according to one embodiment; Fig. 5A, Fig. 5B Block diagrams of alternative further input blocks according to one embodiment show; Fig. 6 shows a block diagram of yet another smart pixel input block according to one embodiment; Fig. Figure 7 shows a block diagram illustrating a smart pixel output block according to one embodiment; Fig. 8 shows a block diagram illustrating another smart pixel output block according to one embodiment; Fig. Figure 9 illustrates an exemplary smart pixel display system according to one embodiment; Fig. 10 shows a timing diagram illustrating an exemplary pixel update timing according to one embodiment; Fig. Figure 11 shows a timing diagram of a smart pixel frame update signal according to one embodiment; Fig. 12A, Fig. 12B and Fig. 12C Block diagrams show various exemplary micromatrix configurations according to one embodiment; Fig. Figure 13 shows a block diagram of an alternative smart pixel microcontroller structure according to one embodiment; Fig. Figure 14 shows a block diagram of an alternative smart pixel microcontroller structure with data transmission according to one embodiment; Fig. 15 shows a flowchart of a method for producing a smart pixel micromatrix display or illumination substrate according to one embodiment; Fig. 16 according to one embodiment shows an illustration of the processing of microdevice substrates from microdevices into a receiving substrate; Fig. Figure 17 shows an illustration of a smart pixel display assembly created from an array of smart pixels mounted on a display or illumination substrate. Detailed description

[0014] Embodiments of the present invention provide a “smart pixel” microcontroller for light-emitting devices. The smart pixel microcontroller utilizes the performance, efficiency, and reliability of wafer-based microcontroller devices to replace the thin-film electronics used to form TFT backplanes. In one embodiment, one or more light-emitting devices are coupled to the smart pixel microcontroller to create a light-emitting smart pixel device. The emitting element of the light-emitting smart pixel device can be one or more light-emitting diode (LED) devices, one or more organic LED (OLED) devices, or one or more micro-LED (µLED) devices.The absence of the TFT manufacturing process makes it possible to produce the smart pixel “micromatrix” using a range of substrates, including rigid, semi-rigid or flexible substrates, glass substrates, plastic substrates or any substrate suitable for the application, since the substrate does not need to undergo a TFT manufacturing process.

[0015] The smart pixel device can be created by transferring one or more LED fixtures and one or more smart pixel microcontrollers onto a receiving substrate prepared with distribution lines to couple each smart pixel microcontroller to its corresponding LED fixtures, other smart pixel controllers, and / or external devices and circuits. The smart pixel device can also include one or more sensors in addition to or instead of one or more LED fixtures. The microcontroller, LED fixtures, and sensor fixtures are bonded to the same side of the substrate surface. The bonds can be created using a variety of connections, such as, but not limited to, pins, conductive contacts, conductive bumps, and conductive spheres.Metals, metal alloys, solders, conductive polymers, or conductive oxides can be used as the conductive materials forming the pins, contact elements, bumps, or spheres. In one embodiment, conductive contacts on the microcontroller, LED devices, or optional sensor devices are thermocompression bonded to conductive contact elements on the substrate. In this way, the bonds can function as electrical connections with the microcontroller, LED devices, or sensor devices. In another embodiment, the bonding involves alloy bonding of the conductive contacts to the conductive contact elements. For example, the conductive contacts or conductive contact elements can incorporate a material such as indium, gold, silver, tin, or copper for bonding.In one embodiment, the conductive contacts and conductive contact elements form an alloy, such as indium-gold, tin-gold, or tin-silver-copper, when bonded together. Other exemplary bonding methods that may be used in embodiments of the invention include, but are not limited to, thermal bonding and thermosonic bonding. In one embodiment, the microcontrollers, LED devices, or sensor devices are bonded to land contact elements in electrical connection with the distribution lines on the substrate to electrically couple one or more LED devices to the smart-pixel microcontroller. The receiving substrate can vary based on the application of the smart-pixel micromatrix. In one embodiment, a display substrate is used to form a smart-pixel micromatrix LED display device in which the smart pixels are used as image elements in a high-resolution display.

[0016] In one embodiment, the smart pixel micromatrix is ​​mounted on a receiving substrate suitable for use in lighting devices. The smart pixel microcontrollers can be used to maintain precise brightness, uniformity, and color control over the emitted light. In one embodiment, the smart pixel micromatrix is ​​used as an LED backlight for liquid crystal display (LCD) devices. Blue or UV LEDs can be used in combination with a yellow, blue-yellow, or white phosphor to provide a white backlight for LCD displays. White light can also be generated by various combinations of single-color LED devices, with or without the use of phosphors. In addition to white illumination, additional single-color LED devices (e.g., red, yellow, green, blue, etc.) can be used.) Devices are used to provide a wider color gamut and color rendering index than would otherwise be possible with white backlighting.

[0017] One or more smart pixel microcontrollers can be coupled to form a microcontroller network. A hierarchy of microcontrollers can be used when there is a multi-layered arrangement between them. Several types of microcontrollers can be used for a variety of applications, and the microcontrollers can be connected via a common data bus, coupled in series, or communicate wirelessly. The microcontroller network can provide fault tolerance and can be used to determine the state of the smart pixel micromatrix.

[0018] In one embodiment, two-way communication is enabled between the smart pixel microcontrollers and other devices in the smart pixel micromatrix. One or more sensors can be coupled to the smart pixel microcontroller along with the emitting elements. The sensors can be ambient light sensors, optical sensors, electrical sensors, or thermal sensors. In one embodiment, for example, a pressure sensor is used to provide visual feedback on a display when it is touched or to transmit user input on a touch-sensitive display. In a smart pixel micromatrix display, sensors can be used to detect drift in the display's white point over time, and the display can be recalibrated periodically to maintain a consistent white point.

[0019] In one embodiment, a smart pixel element is a microscale device created by coupling a microscale (µC) subpixel controller device with a micro-LED (µLED) device. The term "micro" in "microscale," "micro-LED device," "µLED device," "µC device," and "microscale pixel controller" all refer to a scale of 1 to 100 µm. For example, any µLED or µC device may have a maximum (x, y) dimension of 1 to 100 µm. However, it is evident that the embodiments described herein are applicable to larger and potentially smaller scales, depending on the application. In one embodiment, microscale sensor devices are used in conjunction with µLED devices.Exemplary microLED devices and microchips, which according to some embodiments can be used as microscale microcontroller devices, are described in U.S. Patent Application No. 13 / 3711,554. However, embodiments are not limited thereto, and the microLED devices and microchips described in U.S. Patent Application No. 13 / 3711,554 are intended to be exemplary and not limiting. Such microLED devices are highly efficient in light emission and can consume very little energy (e.g., 250 mW for a 25.4 cm (10-inch) display) compared to 5 to 10 watts for LCD or OLED emission. In one embodiment, a smart pixel is created using an OLED as the emitting component. In another embodiment, an inorganic LED is used as the emitting component of the smart pixel.However, it should be evident that the micro-scale smart pixel microcontroller can also be coupled with standard LEDs, and applications are not specifically limited to micro-scale LEDs. In some embodiments, the size of the microLED devices and microcontroller within a smart pixel is determined by the pixel pitch and the resolution of a display. Exemplary display dimensions are described in Table 1 below.

[0020] Various methods and configurations of the smart pixel device are described, including display, illumination, and backlight configurations at different scales. However, certain embodiments can be implemented without one or more of the disclosed specific details or in combination with other known methods and configurations. To provide a thorough understanding, numerous specific details are presented, such as specific configurations, dimensions, and processes. In some cases, generally known techniques and components have not been described in great detail to avoid unnecessary obfuscation of the explanation.

[0021] Within this description, a reference to "an embodiment" or similar indicates that a particular feature, structure, configuration, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearance of the phrase "in an embodiment" or similar at different points within this description does not necessarily refer to the same embodiment of the invention. Furthermore, the particular features, structures, configurations, or characteristics may be combined in any suitable manner in one or more embodiments.

[0022] The terms “above”, “to”, “between”, and “on”, as used herein, can refer to a layer’s relative position with respect to other layers. A layer “above” or “on” another layer, or a layer bonded to another layer, may be in direct contact with that layer or may have one or more intermediate layers. A layer “between” layers may be in direct contact with the layers or may have one or more intermediate layers.

[0023] The term "ON," as used in this description in connection with a device state, refers to an activated state of the device, and the term "OFF" refers to a deactivated state of the device. The term "ON," as used herein in connection with a signal received by a device, refers to a signal that activates the device, and the term "OFF" used in this context refers to a signal that deactivates the device. A device can be activated by a high voltage or a low voltage, depending on the underlying electronics implementing the device. For example, a PMOS transistor device is activated by a low voltage, while an NMOS transistor device is activated by a high voltage.Therefore, it should be understood that an "ON" voltage for a PMOS transistor device and an NMOS transistor device correspond to opposite voltage levels (low as opposed to high). It is also understood that in the case of V. dd and V ss illustrated or described, this also includes one or more V dd and V ss can specify. For example, a digital V dd used for data inputs, digital logic storage devices, etc., while another V dd is used to operate the LED output block.

[0024] Fig. Figure 1 shows a circuit diagram of a smart pixel micromatrix according to one embodiment. In one embodiment, the smart pixel micromatrix 100 replaces the emitting element and the TFT layer of a conventional active matrix display with an integrated circuit device of a microscale (µC) smart pixel microcontroller 110 to switch and operate one or more LED devices 115. In one embodiment, the smart pixel micromatrix 100 is fabricated on a receiving substrate prepared with distribution lines 125 to operate the various µC devices 110 and the LED devices 115. In one embodiment, the distribution lines include sampling lines connected to one or more sampling drivers V. select are coupled, and data lines that are connected to one or more data drivers V dataare coupled. As illustrated, the LED devices 115 are connected to a common ground, but they can also each have a separate ground. In this figure and in the following figures, each illustrated LED device 115 can represent a single LED device or multiple LED devices arranged in series, parallel, or a combination of both, so that the multiple LED devices can be driven by the same control signal. While the exemplary circuit in Fig. Figure 1 illustrates three control inputs and six LED outputs; however, embodiments are not limited in this way. A single µC 110 can control multiple pixels on a display or multiple groups of LED devices 115 for a lighting device. In one embodiment, a single µC 110 can control fifty to one hundred pixels.

[0025] In one embodiment, the microcontroller device 110 is coupled to one or more red, green, and blue LED devices 115 that emit different colors of light. In a red-green-blue (RGB) subpixel arrangement, each pixel comprises three subpixels that emit red, green, and blue light, respectively. The RGB arrangement is exemplary, and these embodiments are not limited in this way. Additional subpixel arrangements include red-green-blue-yellow (RGBY), red-green-blue-yellow-cyan (RGBYC), or red-green-yellow-blue-white (RGBW), or other subpixel matrix schemes in which the pixels may have a different number of subpixels, such as the displays manufactured under the PenTile® trademark.

[0026] In one embodiment, the smart pixel micromatrix is ​​used in LED lighting solutions or as an LED backlight for an LCD device. When used as a light source, blue or UV LEDs can be used in combination with a yellow or blue-yellow phosphor to provide a white backlight for LCD displays. In another embodiment, a smart pixel micromatrix using one or more blue LED devices, such as an indium gallium nitride (INGaN) LED device, is combined with the yellow luminescence from cerium-doped yttrium aluminum garnet (YAG:Ce). 3+)-phosphor combined. In one embodiment, red, green, and blue phosphors are combined with a near-ultraviolet / ultraviolet (nUV / UV) InGaN LED device to produce white light. The phosphor can be bonded to the surface of the LED device, or a remotely positioned phosphor can be used. In addition to emitting white light, an additional red, green, and / or blue LED device can also be used to provide a wider color gamut than would otherwise be possible with white backlighting.

[0027] Fig. Figure 2 shows a block diagram of a smart pixel microcontroller structure according to one embodiment. In one embodiment, the smart pixel microcontroller device 110 has an input block 215 and an output block 225. In another embodiment, the smart pixel microcontroller device 110 has an additional data storage module 210, which can be an analog data storage module with one or more capacitors or a digital data storage module consisting of static random access memory (SRAM), dynamic random access memory (DRAM), or non-volatile memory such as flash memory. The input block 210 is equipped with input pins for power V. dd and mass V ss , as well as one or more input pins V data(1) to V data(n)coupled. The Smart-Pixel-µC 110 is configurable to accept at least one input that can control at least one LED device or at least one group of LED devices in series or parallel, or a combination of the two, such as one or more LED devices that can be used in a white light source. In one embodiment, three input control signals control up to three LED devices (e.g., LED1, LED2, and LED3) with red, green, or blue output to create an RGB subpixel array. In another embodiment, more than three LED devices can be controlled to control subpixel arrays such as red-green-blue-yellow (RGBY), red-green-blue-yellow-cyan (RGBYC), or red-green-blue-white (RGBW), or other subpixel schemes where the pixels can have a different number of subpixels. In one embodiment, the Smart-Pixel-µC 110 has an input pin V select, which is coupled to a sampler driver input to provide a line selection signal. In one embodiment, an explicit line selection input is omitted in favor of using a data update signal on the data input.

[0028] In one embodiment, the output block 225 is configured to output current to the various emitting devices coupled to the µC 110. In configurations using conventional analog driver techniques, the input voltage signals from the input data lines are converted into the corresponding current to power each of the coupled subpixels. For example, a voltage input to V data(1) Operate the output LED1 in an LED lighting device. If the input module of the µC 110 has multiple inputs, such as V data(1) to V data(n) , the output block 225 can control up to n control lines from LED1 to LED nOutput. One or more LEDs in series, parallel, or a combination can be coupled to one or more LED outputs.

[0029] In one embodiment, the Smart-Pixel-µC 110 has a data storage module 220 to store data values ​​when inputs are received. The data storage module 220, which can be an analog or digital data storage module, stores the data associated with each display update. In one embodiment, the data storage module 220 includes one or more capacitors to store an incoming analog voltage from an analog input block. In another embodiment, the data storage module 220 includes at least one random access memory (RAM) cell, such as static RAM (SRAM) or dynamic RAM (DRAM), to store a digital value. In another embodiment, the data storage module 220 includes flash memory.When the data storage module 220 is enabled, the Smart Pixel microcontroller 110 stores the incoming data for each pixel and can continuously display data with minimal or no need for regular updates of static data. Instead, the pixel can continue to display the stored data until the display control unit indicates an update event. Additionally, multiple frames of pixel data can be transmitted to the Smart Pixel microcontroller 110 in a burst and stored in the memory module 220. The Smart Pixel microcontroller 110 can then process the multiple frames at a specific update frequency or based on an update signal from the display control unit.

[0030] Fig. Figure 3 shows a block diagram of an alternative smart pixel microcontroller according to one embodiment. In one embodiment, the smart pixel microcontroller 310 has an input block 315, a data storage module 320, and an output block 325. As in the one shown in Fig. The analog variant shown in 2, 110, has the digital variant 310 voltage inputs V. dd and V ss as well as an optional sampling line or line selection input V select 205. In one embodiment, the output (e.g., LED1 to LED) nThe digital smart pixel microcontroller 310 is coupled to one or more LED devices in an LED lighting device or an LED backlight. In one embodiment, three or more LED devices in a red-green-blue (RGB) subpixel arrangement or another subpixel matrix can be controlled for use in a smart pixel micromatrix display device. Inputs are provided via a digital input 305, which can be a connection to a digital data bus, a digital data link, or a differential signal interface.

[0031] In one embodiment, the data storage module 320 buffers inputs received by an input block 315 for subsequent use by the output block 325. The data storage module 325 can contain memory such as DRAM, SRAM, or flash memory to store input data between update cycles. In one embodiment, all input data for a display frame is sent individually as a burst message to each smart pixel microcontroller 310, which stores the pixel or subpixel information for the connected LEDs. The output module 325 can read the stored data and operate the connected LEDs at a standard update frequency or a content-dependent update frequency.

[0032] Fig. Figure 4 shows a block diagram of an input block of a smart pixel microcontroller according to one embodiment. In one embodiment, the input block 215 is coupled to a data input 405 and a line select or sample input 205. The input block 215 can use one or more variants of a sample and hold circuit 406. The exemplary sample and hold circuit 406 has a transistor T1 402 and a capacitor Cs 404, although more complex sample and hold circuits can also be used. The switching transistor 402 can be any type of insulated-gate field-effect transistor, such as an n-type or p-type semiconductor transistor.In this configuration, the switching transistor T1 402 has a gate electrode coupled to the sampling input 205, a first source / drain electrode coupled to the data input 305, and a second source / drain electrode coupled to the capacitor Cs. In one embodiment, a voltage-level sampling signal activates charging of the capacitor Cs 404, which ultimately enables current flow to the LED devices coupled to the output module. In another embodiment, the input module is coupled to an output module containing a driver transistor. In such an embodiment, the microcontroller forms a circuit similar to the 2T1C circuit of an active matrix display, although additional circuit configurations are possible. In one embodiment, the input module charges one or more capacitors in the memory module 220.The memory module 220 can also contain a digital memory instead of or in addition to the one or more capacitors, and an analog-to-digital converter (ADC) 430 is used to store a digital representation of the analog input.

[0033] Fig. Figure 5A shows a block diagram of an input block of a smart pixel microcontroller coupled to a digital memory with an analog data input. In one embodiment, the input block 215 is coupled to a data input via a data input pin and provides an output for a data storage module 320. In another embodiment, a data synchronization logic 520 detects an analog update signal on the data line and forwards the incoming data to an ADC 530 to store a digital representation of the input data in the data storage module 320. In another embodiment, the update signal serves as an indicator for the data test logic to update the pixel state value with a new value.

[0034] Fig. Figure 5B shows a block diagram of an input block of a smart pixel microcontroller coupled to a capacitive memory and featuring an analog data input. In one embodiment, the input block 215 is coupled to a data input via a data input pin and provides an analog signal to a data storage module 220, which uses capacitive memory. The data synchronization logic 520 detects an analog update signal on the data line 505 and forwards the updated data to the capacitive memory 220.

[0035] Fig. Figure 6 shows a block diagram of an exemplary smart pixel input block according to one embodiment. The digital input block 315 is coupled to one or more digital input pins 305 and is coupled to a data storage module 220, which may contain capacitive memory and / or one or more cells of a digital memory, such as SRAM or DRAM, or non-volatile memory such as flash memory. An input receiver 540 is coupled to the digital input 305 and receives data from the one or more input pins and stores the received data in the data storage module 220. In one embodiment, a sampling line 205 is coupled to the input block to allow a sampling line to signal a data update. In one embodiment, the data update events are executed via the digital input.

[0036] Fig. Figure 7 shows a block diagram illustrating a smart pixel output block according to one embodiment. In one embodiment, the smart pixel microcontroller device 110 has an output block 225 configured to be coupled to an analog input block or a capacitive memory. The output block 225 can use one or more variants of a voltage-to-current converter circuit 720 for each LED output. The exemplary voltage-to-current converter has a driver transistor T2 702, which is connected to a voltage source V. dd It has a coupled first source / drain electrode and a second source / drain electrode coupled to one or more LED devices. A storage capacitor Cs 704 coupled to the gate electrode of the driver transistor T2 702 can be included in one version of the output block, or can be in the input block (e.g., Cs 404 of Fig. 4) be included as part of a connection switching logic between the input block 215 and the output block 225, or it is one of the one or more capacitors in the storage module 220. A first electrode of the storage capacitor Cs 704 is connected to a ground line V ss connected or can have its own ground. A second electrode is coupled to the gate electrode of the driver transistor T2 702. The voltage potential stored within the storage capacitor Cs opens the gate of the driver transistor T2 702 to conduct current to one of the several connected LED devices. Each LED device (e.g., LED1, LED2 to LED) nThe driver can be used for a single LED device or one or more LED devices in parallel, in series, or a combination thereof. It should be noted that the specific driver methods used by the voltage-to-current converter 225 are for illustrative purposes only, and alternative LED driver circuits are within the scope of the various embodiments and may vary depending on whether the implementation is display-oriented, illumination-oriented, or backlight-oriented.

[0037] Fig. Figure 8 shows a block diagram illustrating another smart pixel output block according to one embodiment. In one embodiment, a smart pixel output block 325 can read from a digital memory in the data storage module 220 and has a digital control logic 830 coupled to a digital-to-analog converter (DAC) 840. A serial data link from the digital control logic to the DAC can be used to control one or more connected LEDs.

[0038] It should be noted that the specific driver methods used by output block 325 are for illustrative purposes only, and alternative LED driver circuits fall within the scope of the various embodiments and may vary based on whether the implementation is display-, illumination-, or backlight-oriented. Additionally, each LED device (e.g., LED1, LED2 to LED) can be n) for a single LED device or one or more LED devices in parallel, in series or in a combination.

[0039] Fig. Figure 9 illustrates an exemplary smart pixel display system according to one embodiment. In this example, a display field 920 has a mixed display mode in which dynamic content 930, such as a video stream, is shown in a window, while the rest of the display shows static content 920, such as a text page. A data input can be coupled to input pins of the smart pixel microcontroller (µC) device 922. In one embodiment, an enable / ignore signal 905 is coupled to a sample input and is used to transmit address information, frame update information, or frame metadata to the smart pixel microcontroller. In one embodiment, both data and address information are transmitted via the data input 910.The smart pixel micromatrix 920 can correspond to a single display or a section of a display, such as a high-definition (HD) television or a large outdoor display. In one embodiment, the microcontroller device 922 can be coupled to other microcontrollers via a microcontroller link 935. In another embodiment, the smart pixel micromatrix 920 can be a component of a segmented or modular display created by coupling the microcontroller device 922 to an additional microcontroller with an attached smart pixel micromatrix. Coupling multiple smart pixel micromatrix assemblies and connecting each microcontroller device 922 can create progressively larger displays using a modular configuration. In one embodiment, the microcontroller link 935 can be a wireless connection.In one embodiment, one or more µC devices can be used as repeater devices in a network of microcontroller connections 935.

[0040] Fig. Figure 10 shows a timing diagram illustrating an exemplary pixel update timing according to one embodiment. In the example of Fig. 10. New data is transmitted whenever new content is available for a subpixel provided by an embodiment of the smart pixel microcontroller device, such as the Smart Pixel Microcontroller Device 922 from Fig. 9, is controlled. New data can be transmitted to the µC device 922 and stored in a memory module. Each time new data is available for a subpixel controlled by the µC device 922, data is transmitted without following a fixed schedule. A periodic update operation is not required, as described in Fig. Figure 10 shows the horizontal lines indicating idle periods. In one embodiment, frame data is transmitted faster than the scheduled display update frequency, and the pixel data is stored in an embodiment of the microcontroller device memory module (e.g., memory module 220, memory module 320). The pixel data is then read from the memory module at a scheduled update interval. This allows multiple frames of data to be sent in burst mode, received through an input block of the microcontroller device 922, and read from the memory module through the output block at the appropriate interval.

[0041] Fig. Figure 11 shows a timing diagram of a smart pixel frame update signal according to one embodiment. In one embodiment, an analog data input V detects data(n) Voltages between a value of V dd and a value of V ss For example, V can dd+5 V, and V ss can be -5 V. Alternatively, V dd any positive or negative voltage, and V ss is connected to ground. In microscale implementations, the voltages can be much smaller, while in outdoor lighting and display implementations, the voltages can be higher. The analog voltage signal is captured by the 420 data synchronization logic, which is coupled to an analog-to-digital converter (ADC). A digital subpixel data value is derived from the analog input voltage value. For example, a drop to V ssThe indicator 1110 can function as a synchronization indicator for a data synchronization logic (e.g., the data synchronization logic 520). The data synchronization logic 520 can then forward the indicator for incoming data 1120 to the ADC switching logic 430 to store the analog input as a digital value in the data storage module 220. In one embodiment, the incoming data value is stored in a capacitive memory module in the data storage 220.

[0042] Fig. 12A, Fig. 12B and Fig. Section 12C shows block diagrams illustrating various exemplary micromatrix configurations. Fig. Figure 12A illustrates a smart pixel micromatrix that includes one or more smart pixel microcontroller devices 1230 and a matrix of LED devices 1250, which can be conventional LED devices, organic LED devices, or microLED devices. Each microcontroller device 1230 can control a single LED, or a single microcontroller device 1230 can control the micromatrix 1240. In one embodiment, the micromatrix is ​​addressed in a row / column configuration. In another embodiment, each LED device 1250 is addressed individually. In yet another embodiment, microLEDs are used to create a high-density, high-resolution display.In one embodiment, LED devices known in the prior art are used for large outdoor displays, and one or more microcontroller devices 1230 can be connected in a network to control the display, with different microcontroller devices 1230 acting as tile control units for each segment of the display. In one embodiment, each segment can communicate via a microcontroller connection 935, as shown in [reference]. Fig. Figure 9 illustrates this. In one embodiment, the micromatrix 1240 is an LED light source for producing white or colored light either by LED emission or by emission and phosphorescence. In another embodiment, the micromatrix 1240 is an LED backlight for an LCD display.

[0043] Fig. Figure 12B illustrates an embodiment in which a microcontroller (µC) controls a grid of LED devices 1250 in a "passive" micromatrix configuration, where the LEDs are arranged in rows and columns. The LEDs can be coupled in series, parallel, or in a combination with each LED output pin of the µC device 1230. One or more µC devices 1230 can be used as a microcontroller for the LED devices.

[0044] Fig. Figure 12C illustrates yet another arrangement between LED and microcontroller devices according to one embodiment. Each LED device 1250 can be connected to a single output pin of the smart pixel microcontroller device 1230. The LED devices 1250 can each be blue or UV LED devices used with a remotely located phosphor to produce white light. In one embodiment, the LEDs are blue LED devices using a directly applied phosphor such as a YAG:Ce3 phosphor. The LED devices 1250 can also be part of a display device. The four LEDs illustrated can be configured as RGBY subpixels, or additional LED devices, such as five LED devices, can be used to create an RGBYC array.

[0045] Fig. Figure 13 shows a block diagram of an alternative smart pixel microcontroller according to one embodiment. In one embodiment, a smart pixel microcontroller 1310 includes one or more embedded sensor devices 1302, such as an optical, electrical, thermal, or pressure sensor. The embedded sensors 1302 can be coupled to a sensor data control unit 1304. In one embodiment, the sensor data control unit 1304 is coupled to one or more chip-external sensors 1301 to receive additional sensor data from the chip-external sensors 1301. In one embodiment, sensor logic 1312 for processing sensor data from embedded or external sensors is coupled to the sensor data control unit 1304 and the data storage module 1320. Sensor data processed by the sensor logic 1312 can be stored in the data storage module 1320.In one embodiment, an external communication module 1306 enables a microcontroller connection 935 with other µC devices, as in . Fig. 9 illustrates.

[0046] Some Smart Pixel microcontroller variants configured for sensor inputs can also control LED devices. In one embodiment, the Smart Pixel microcontroller 1310 has an input block 1315, the data storage module 1320, and an output block 1325. In another embodiment, the Smart Pixel microcontroller 1310 has a digital input 305, similar to the digital input of the [missing information]. Fig. 3 Smart Pixel microcontrollers 310 shown, as well as voltage inputs V dd and V ss In one embodiment, the output (e.g., LED1 to LED) nThe digital Smart Pixel microcontroller 1310 is coupled to one or more LED devices in an LED lighting fixture or LED backlight. Each LED device output can be coupled to one or more LED devices in series, parallel, or a combination of series and parallel.

[0047] Fig. Figure 14 shows a block diagram of an alternative smart pixel microcontroller according to one embodiment. In one embodiment, a smart pixel microcontroller 1410 configured for digital inputs has, in addition to voltage inputs V dd and V ss a data storage module 320 and an output block 325 similar to the Smart Pixel uC 310 from Fig. 3. In one embodiment, the Smart-Pixel-µC 1410 additionally has an input block 1415 coupled to a forwarding output 1417 in order to forward or retransmit incoming digital inputs 305 to one or more additional Smart-Pixel-µCs. In one embodiment, the Smart-Pixel-µC 1410 operates outputs to one or more LED devices (e.g., LED1 to LED1). n Each LED device output can be coupled to one or more LED devices in series, parallel, or a combination of series and parallel.

[0048] Fig. Figure 15 shows a flowchart of a method for producing a smart pixel display according to one embodiment. An exemplary method for fabricating microscale devices, such as microscale LED devices (µLEDs) and microchips, such as integrated circuits of microcontrollers (µCs), is described in the previously filed U.S. Patent Application No. 13 / 711,554. The µLED devices and µCs are prepared on separate substrates and float for pick-up and transfer using an array of electrostatic transfer heads. For example, arrays of red-emitting µLED devices, blue-emitting µLED devices, and green-emitting µLEDs are prepared on separate substrates. Likewise, an array of µCs is prepared on a separate substrate.As shown in Block 1502, an array of electrostatic transfer heads is positioned over a carrier substrate supporting a plurality of µLED devices and picks up the plurality of µLED devices from the carrier substrate. As shown in Block 1504, the array of µLED devices is placed in the appropriate position on the receiving substrate. The same or a different array of electrostatic transfer heads is then used to pick up, transfer, and position each of the separate arrays of µLED devices for each color used in the smart pixel array on the receiving substrate. The receiving substrate can be, but is not limited to, a display substrate or a lighting substrate.As shown in block 1506, the same or a different arrangement of electrostatic transfer heads is positioned over the substrate supporting an arrangement of LED microcontroller devices and picks up the arrangement of microcontroller devices from the microcontroller substrate. As shown in block 1508, each microcontroller device is transferred to the same receiving substrate as the arrangements of LED microcontroller devices and placed in the appropriate position on the receiving substrate. In one embodiment, one or more sensor devices are also placed on the receiving substrate. As shown in block 1510, the same or a different arrangement of electrostatic transfer heads as used for the LED microcontroller devices and the microcontrollers is positioned over the substrate supporting an arrangement of sensor devices and picks up one or more of the sensor devices from the sensor carrier substrate.As shown in Block 1512, each µSensor device is transferred to the same receiving substrate as the arrangements of µLED devices and placed in the appropriate position on the receiving substrate.

[0049] Fig. Figure 16 shows an illustration of the processing of microdevice substrates from microdevices onto a receiving substrate, according to one embodiment. Separate carrier substrates are used for each µLED color 1610, for the µCs 1620, and for the µsensors 1625. One or more transfer assemblies 1600 can be used to pick up microstructures from the carrier substrates (e.g., 1610, 1620, 1625) and transfer them onto the receiving substrate, such as a display or illumination substrate 1630, to form a smart pixel array 1615. In one embodiment, separate transfer assemblies 1600 are used to transfer any combination of µLED colors 1610, µCs 1620, and µsensors 1625. The display substrate is prepared with distribution lines to connect the various µLED and µC structures.Multiple distribution lines can be coupled to landing contact pads and a connection structure to electrically couple the microLED and microcontroller devices and to couple the various microcontroller devices to each other. The receiving substrate can be a 1630 display substrate of any size, ranging from micro-displays to large-area displays, or it can be a backlight substrate for LED illumination or for use as an LED backlight for an LCD display. The microLED and microcontroller structures are bonded to the same side of the substrate surface.

[0050] The bonds can be created using a variety of connection types, including but not limited to pins, conductive contact elements, conductive bumps, and conductive spheres. Metals, metal alloys, solder, conductive polymers, or conductive oxides can be used as the conductive materials forming the pins, contact elements, bumps, or spheres. In one embodiment, heat and / or pressure can be transferred from the array of transfer heads to facilitate bonding. In another embodiment, conductive contacts on the microcontroller, LED devices, or optional sensor devices are thermocompression bonded to conductive contact elements on the substrate. In this way, the bonds can function as electrical connections with the microcontroller, LED devices, or sensor devices.In one embodiment, the bonding involves indium alloy bonding or gold alloy bonding of the conductive contacts to the conductive contact elements. Other exemplary bonding methods that may be used in embodiments of the invention include, but are not limited to, thermal bonding and thermosonic bonding. In one embodiment, the microcontrollers, LED devices, or sensor devices are bonded to land contact elements in electrical connection with the distribution lines on the substrate to electrically couple one or more LED devices to the smart-pixel microcontroller. The receiving substrate can vary based on the application of the smart-pixel micromatrix. In one embodiment, a display substrate is used to form a smart-pixel micromatrix LED display device in which the smart pixels are used as image elements in a high-resolution display.

[0051] Fig. Figure 17 shows an illustration of a smart pixel assembly created from an array of smart pixels mounted on a lighting or display substrate. In one embodiment, the receiving smart pixel substrate is a smart pixel micromatrix 1730 prepared with distribution lines to couple the micromatrix of microcontroller devices and LEDs to one or more control units. The LED smart pixel micromatrix can be configured in the Fig. The smart pixel micromatrix assemblies are placed on the prepared substrate 1730 as described in Section 16. In one embodiment, the receiving substrate 1735 is a display substrate, and several smart pixel micromatrix assemblies can be coupled together to form a high-resolution display system. In another embodiment, the receiving substrate 1735 is an illumination substrate, and one or more smart pixel micromatrix assemblies can be used with a yellow phosphor to form a white light source. In another embodiment, one or more sensors, which may be sensors known in this field or microscale sensors with a maximum (x, y) dimension of 1 to 100 µm, can be used to detect drift in the white point of the display over time, and the display can be recalibrated periodically to maintain a consistent white point.

[0052] An optional sealant 1740 can be used to secure and protect the substrate. In one embodiment, the sealant is transparent to allow a display or illumination substrate with upward-emitting LED devices to be seen through the sealant. In one embedding, the sealant is opaque for use with downward-emitting LED devices. In one embodiment, a data driver 1710 and a sampler driver 1720 with multiple data and sample lines are coupled to the display substrate. In one embodiment, each of the smart pixel devices is coupled to an update and timing control unit 1724. The update and timing control unit 1724 can address each LED device individually to enable asynchronous or adaptively synchronous display updates.In one embodiment, a brightness control unit 1726 can be coupled to the micromatrix substrate 1735, which is used to control the brightness of an LED micromatrix LED lighting device that can also be used as a backlight in an LCD. The brightness control unit 1726 can also be coupled to one or more optical sensors to enable adaptive adjustment of the light output. In another embodiment, one or more thermal sensors enable automatic management of the heat dissipation of a smart-pixel-based LED light source.

[0053] Table 1 provides a list of exemplary implementations according to the various embodiments that use red-green-blue (RGB) displays with resolutions of 1920 × 1080 pixels and 2560 × 1600 pixels. It can be seen that embodiments of the invention are not limited to RGB color schemes or the resolutions of 1920 × 1080 pixels or 2560 × 1600 pixels, and that the specific resolution and RGB color scheme are for illustrative purposes only. Table 1: Anzeigesubstrat Pixelabstand(x, y) Subpixelabstand(x, y) Pixel / cm (Pixel proZoll (Pixels perinch PPI) 139,7 cm (55 Zoll)1920 x 1080 (634 µm, 634 µm) (211 µm, 634 µm) 15,75 (40) 25,4 cm (10 Zoll)2560 × 1600 (85 µm, 85 µm) (28 µm, 85 µm) 117,7 (299) 10,16 cm (4 Zoll)640 × 1136 (78 µm, 78 µm) (26 µm, 78 µm) 128,3 (326) 12,7 cm (5 Zoll) (58 µm, 58 µm) (19 µm, 58 µm) 173,2 (440) 11920 × 1080

[0054] In the foregoing exemplary embodiments, the pixel density of 15.75 pixels / cm (40 PPI) can correspond to a 139.7 cm (55-inch) television with a resolution of 1920 × 1080 p, and the 128.3 and 173.2 pixels / cm (pixel densities of 326 and 440 PPI, respectively) can correspond to a handheld device with a retina display. According to embodiments of the invention, the maximum (x, y) dimensions of the µLED devices and the µC for a Smart Pixel 120 fit within the allocated pixel pitch, as described above in reference to Table 1.For example, in one embodiment, an RGB display measuring 12.7 cm (5 inches) and 173.2 pixels / cm (440 PPI) may include a red-emitting µLED device, a green-emitting µLED device, and a blue-emitting µLED device, each with a maximum (x, y) dimension that fits within the corresponding subpixel spacing of (19 µm, 58 µm), and a µC device that fits within the pixel spacing of (58 µm, 58 µm). For example, in one embodiment, an RGB display measuring 139.7 cm (55 inches) and 15.75 pixels / cm (40 PPI) may include a red-emitting µLED device, a green-emitting µLED device, and a blue-emitting µLED device, each with a maximum (x, y) dimension that fits within the corresponding subpixel spacing of (211 µm, 634 µm), and a µC device that fits within the pixel spacing of (634 µm, 634 µm).

[0055] When considering the various aspects of this invention, it will be apparent to the person skilled in the art that combinations or variations of the aforementioned smart pixel embodiments are possible. Although the present invention has been described in language specific to the structural features and / or procedural actions, it is understood that the invention defined in the appended claims is not necessarily limited to the specific features or actions described. Instead, the disclosed specific features and actions are to be understood as particularly advantageous implementations of the claimed invention, which are useful for illustrating the present invention.

Claims

[1] Light-emitting assembly (100), comprising: an arrangement of light-emitting diode (LED) devices (115); and an arrangement of microcontrol units (110) for switching and operating the arrangement of LED devices (115), wherein the arrangement of LED devices (115) and the arrangement of microcontrol units (110) are bonded to the same side of a substrate, the number of microcontrol units (110) in the arrangement of microcontrol units (110) is less than the number of LED devices (115) in the arrangement of LED devices (115), and each microcontrol unit (110) in the arrangement of microcontrol units (110) is in electrical contact with a plurality of pixels comprising the arrangement of LED devices (115); wherein each microcontroller (110) is a microchip and comprises a plurality of microcontroller LED outputs; wherein each plurality of pixels comprises a plurality of groups of LED devices (115) and each microcontroller LED output is coupled to a corresponding group of LED devices (115); and wherein each group of LED devices (115) is coupled in parallel to a corresponding microcontroller LED output. [2] Assembly (100) according to claim 1, wherein each microcontrol unit (110) is a microchip and each microcontrol unit (110) and each LED device (115) are bonded to the substrate with indium, gold, silver, copper or alloys thereof. [3] Assembly (100) according to claim 1, wherein each micro control unit (110) in the arrangement of micro control units (110) has a maximum length or width dimension of 1 to 100 µm and each LED device (115) in the arrangement of LED devices (115) has a maximum length or width dimension of 1 to 100 µm. [4] Assembly (100) according to claim 1, wherein the arrangement of LED devices (110) are bonded to landing contact elements in electrical contact with distribution lines on the same side of the substrate. [5] Assembly (100) according to claims 1 to 4, wherein each microcontrol unit (110) in the arrangement of microcontrol units (110) includes one or more input circuits (215) and at least one output circuit (225). [6] Assembly (100) according to claim 5, wherein each of the one or more input circuits (215) is coupled to a capacitive storage module (220). [7] Assembly (100) according to claim 5, wherein the input circuit (215) further comprises an analog-to-digital converter coupled to a data storage module. [8] Assembly (100) according to claim 1, wherein each microcontrol unit (110) in the arrangement of microcontrol units (110) includes a digital logic, the digital logic including an input logic block (215), an output logic block (225) and a data storage module (220). [9] Assembly (100) according to claim 8, wherein the data storage module (220) comprises at least one bank of random access memory. [10] Assembly (100) according to claim 9, further comprising: a data driver coupled to the substrate; and a scanning driver coupled to the substrate. [11] Assembly (100) according to claim 10, further comprising a time clock control unit coupled to the data driver, wherein the time clock control unit is operable to signal to the sampling driver that a first line of a display field in a current data frame is not to be updated and a second line of the display field in the current data frame is to be updated. [12] Assembly (100) according to claim 1, wherein each microcontrol unit (110) is a microchip and each microcontrol unit (110) and each LED device (115) are bonded to landing contact elements in electrical connection with distribution lines to electrically couple the arrangement of microcontrol units (110) and the arrangement of LED devices (115). [13] Assembly (100) according to claim 1, wherein several micro control units (110) in the arrangement of micro control units (110) include an external communication module to exchange data between the several micro control units (110). [14] Assembly (100) according to claim 1, wherein the substrate is a lighting substrate. [15] Assembly (100) according to claim 1, further comprising a sensor device, wherein the sensor device includes one or more of a thermal sensor, an optical sensor or a pressure sensor.

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