Current Position: Home > IP News > New patents of apple and Microsoft micro led exposed

The new patents of apple and Microsoft are exposed, and the patent competition of micro LED is becoming more and more intense.

At a time when the two leading chip companies in China, San'an optoelectronics and Huacan optoelectronics, filed lawsuits for patent infringement, foreign giants such as apple and Microsoft have successively announced new patents related to micro led.

There is no doubt that patents have become the focus of competition among manufacturers, especially in the field of micro led, which is a promising new display technology. In the past two years, the number of patent applications for micro LED has increased rapidly, and the patent competition is full of smoke.


Apple has another micro led patent

According to patentlyapple, the U.S. patent and Trademark Office has officially announced a new Apple patent, covering the future MacBook, iPad and fitness bracelet with micro LED screen.

One of the inventors of the patent is Torre Nauta, senior manager of hardware engineer at Apple. In 2014, Nauta's former employer, luxvue, was acquired by apple, and Nauta subsequently joined apple. At that time, apple obtained 21 patents related to micro led, including those already approved and under application.


Photo source: U.S. patent and Trademark Office

Photo source: U.S. patent and Trademark Office

Apple won a patent on fitness bracelets in June 2020, which does not guarantee that Apple will enter this segment of the wearable device market, but it seems that they are keeping the program alive.

It is reported that this is a highly technical patent. The "IR drop" mentioned in the Apple patent refers to "the potential difference between the two ends of the conductive phase in the current process, and the voltage drop on any resistor is the product of the current (I) passing through the resistance and the resistance value (R)"

Apple's display engineer said that "the decline in infrared may lead to distortion of the display, which Apple will try to solve before bringing the micro LED display to market."

Apple plans to use new display technologies such as miniled and micro led in future new products. Over the years, Apple has been committed to promoting the commercialization of cutting-edge display manufacturing methods, and has obtained a number of related patents.


Microsoft's new patent proposes micro LED display scheme

The U.S. patent and Trademark Office has issued a Microsoft patent related to lightweight ar glasses. It is reported that the inventor of the patent comes from the hololens team of Microsoft. It mainly describes a micro optical solution using micro LED light source, aiming to reduce the volume of AR glasses.

It is understood that at present, the size problem limits the optical or display components that can be integrated into head display devices, and prevents manufacturers from reducing the overall size of head display devices to improve product mobility.

Because it can provide high standard display performance, micro displays such as LCOS or DLP projectors are commonly used in head displays. This display has the advantages of high resolution, wide gamut, high brightness and high contrast. However, digital projection systems that rely on LCOS or DLP technology require large-scale shape parameters to create uniform illumination of panels.

Therefore, Microsoft proposed an AR optical module based on micro LED array, hoping to solve this problem through the patent application named "micro LED display system".

This invention of Microsoft aims to improve the method of using miniaturized components to display images without affecting the display quality or user experience.

The patent document first states that "microled arrays provide a small-scale solution for head display image sources because they do not require separate lighting optics. Future devices such as smart glasses feature microled display systems with multiple monochrome projectors to generate three monochromatic images, such as red, blue and green images. The three monochromatic images can be input into a single waveguide of the head display respectively and combined into one image for display to the user. "

By using a single waveguide that includes multiple spatially separated input regions, such as an area for blue light input, an area for red light input, and an area for green light input, the microled display system used may reduce the shape parameters of the head display device due to the reduction in the number and / or size of the optical elements.


BOE micro led transfer technology patent

The display manufacturers' active investment in R & D has accelerated the growth of recent patent applications. BOE ranked first in the number of applications, and nearly 150 new patent families appeared in 2019 alone.

The innovation of 5g technology has led to the development of mobile phone panel industry. Its high transmission rate and low delay characteristics have created the application of mobile phones in other fields such as ar. therefore, the demand for high refresh rate panel has been put forward, which has led to the development of micro led.

Compared with the existing OLED or LCD, micro LED display has the advantages of independent pixel control, self illumination, high brightness, wide color gamut, stable performance and long service life. With massive transfer technology, it can combine different display backbones to create transparent, projection, bending and flexible display effects. In the future, it is likely to create a new market in the display industry, which is very potential The next generation of new display technology of force. However, there are many problems in the production of micro LED display, such as how to transfer the miniaturized, high-density and array LED grains to the circuit board, which greatly restricts the large-scale commercial application of micro LED display. Based on this situation, BOE, as a well-known domestic display enterprise, proposes a transfer method of micro led.

As early as June 10, 2019, BOE applied for an invention patent named "a micro led transfer method" (application No.: 201910497258. X), and the applicant was BOE Technology Group Co., Ltd.

This patent introduces a transfer method of micro led, which can realize the transfer of LED grains and reduce or eliminate the gap between LED grains and target substrate, which can be widely used in the display field.

Figure 1 flow chart of micro led transfer method

Figure 2 Schematic diagram of donor substrate

Fig. 1 flow chart of micro led transfer method proposed for this patent. Firstly, a donor substrate is provided, including the bearing substrate and the LED grains arrayed on it. As shown in Fig. 2, 100 represents the bearing substrate and 101 represents the micro LED grain. Compared with the ordinary LED grain with the size of millimeter, the size of micro LED is micron, so the process is more difficult. In the S100 step of Fig. 1, the LED grains need to be arranged on the donor substrate. Firstly, n-type semiconductor layer, light-emitting layer and p-type semiconductor layer should be grown on the substrate, and then etched to form multiple n-type or p-type semiconductor patterns, luminous patterns and positive and negative electrodes, so as to form multiple LED grains and ensure that they are not connected with each other.


Fig. 3 Schematic diagram of pasting substrate

The 101 step in Fig. 1 provides a bonding substrate, including a bottom plate and a hot melt adhesive film covered on it. As shown in Fig. 3, 200 represents the bottom plate and 201 represents the hot melt adhesive pattern. The purpose is to ensure that each LED grain can correspond to the hot melt adhesive plan 2011 when the bonding substrate is directly opposite to the donor substrate, so as to efficiently transfer the grains. When performing the S102 step in Fig. 1, the adhesive substrate 20 is moved above the donor substrate 10, and the adhesive substrate 20 is moved in the direction close to the donor substrate 10. The LED grain 101 on the bearing substrate 100 is pasted with the adhesive substrate 20 to separate the LED grain 101 from the bearing substrate 100. The S103 step in Fig. 1 shows that the pasted substrate with a plurality of LED grains is moved over the target substrate (such as a circuit board), and the corresponding positions of the LED grains and the target substrate are completely aligned, so that the LED grains are electrically connected with the driving electrode pairs on the circuit board.

Fig. 4 Schematic diagram of grain transfer process of micro LED

The S104 process in 1 represents the grain transfer process of micro led, and the schematic diagram is shown in Fig. 4, where 30 represents the target substrate. The adhesive substrate with multiple LED grains is heated to the first temperature (higher than the melting temperature of the hot melt adhesive film) to melt the hot melt adhesive film 201. The LED grain is separated from the bonding substrate. Since the grain position is directly opposite to the preset position on the target substrate, the separated LED grains will be transferred to the target substrate.

According to figure 4, it can be seen that there is a gap h between the LED grain and the target substrate, which has a great impact on the display and luminous effect. The method proposed in this patent can make the melted hot melt adhesive film flow into the gap between the LED grain and the target substrate, thus reducing the gap between the LED grain and the target substrate. However, the existing technology generally adopts the method of absorbing and pressing LED grains one by one to transfer a large amount of LED grains to the target substrate. Due to the large number of LED grains, it is very difficult to transfer, resulting in high cost. The transfer method proposed in this patent can transfer multiple LED grains 101 at the same time, thus simplifying the transfer difficulty of large amount of LED grains and improving at the same time The influence of break off on display and luminous effect is also discussed.


Samsung issues a patent for micro LED TV

Earlier, Samsung Electronics issued a patent describing a modular micro LED TV. Give a brief explanation in advance. Even if the description of this patent is comprehensive and detailed, it does not mean that Samsung will continue to pursue the development or production of corresponding products. Ideas or "sudden collapse" projects are often patented to protect them from competition. Samsung's patent w02020116861 "display device" is a panel with printed circuit board, which is equipped with several display modules vertically. As shown in the figure below:


The slim micro LED module (A1) has an overall dimension of 1:10 and is connected to the circuit board at the top and bottom. The 40 modules can be assembled into a 1:1 image mode (W1). The classic 16:9 format (W2) continues to add 22 modules. More than that, the shape can even be extended to a 21:9 ultra wide display (W3).

The module consists of hundreds of micro LED pixels, and each pixel is divided into red, green and blue sub pixels. The arrangement of subpixels in the pixel is not clear for the time being. It may be arranged as a triangle or elongated sub-pixel is arranged adjacent to each other. The resolution of the display is mentioned in the patent. According to the conventional format of 16:9, the resolution is 3840 x 2160, which is 4K Ultra HD. With the increase of pixel density, 8K (7680 x 4320) is also possible.

There are actually four complete components. Micro LED light source module, printed circuit board, substrate for placing micro LED module and transparent protective layer. The transparent protective layer is used to prevent the entry of dust, splash water and other foreign matters.

[warm tips] source: Internet. The copyright belongs to the original author. If there is something wrong, please contact to inform us of modification or deletion. Thank you.

One on one service for appointment experts