Mini-LEDs

Sony has announced that it has developed a new next-generation display technology, which it refers to as RGB LED backlighting, which basically uses red, green and blue mini-LEDs to drive LCD displays.

Current mini-LED backlighting units use blue LEDs, color converted into white color, to form the backlighting of LCD displays. In its new technology, Sony uses three different miniLEDs in each dimming zone, which removes the need to color convert. Sony says that its new technology can enable brighter (up to 4,000 nits) displays with an increase color gamut and wider viewing angles. The company demonstrated a 75-inch RGB LED LCD display that uses 96,000 LEDs to create 32,000 dimming zones.

Adhesive developer and MicroLED Association member DELO has conducted in-house feasibility studies, that shows that their directional conductive adhesives can be used to replace soldering in miniLED, and microLED displays. The bonding was found to be reliable with high yields.

DELO says that current microLED displays use solder materials to interconnect the LEDs to the display backplane. But as chip size gets smaller, isotopic conductive materials (like solder) is not reliable as it is difficult to avoid short circuits, and so production yields suffer.

China-based HC Semitek is embarking on a 5 billion Yuan project (almost $700 million USD) to produce microLED wafers in Jinwan District, Zhuhai, China. The project will have three phases, with the first one (estimated at $275 million) has officially started last month.

HC Semitek hopes to light up the new production line in September 2024, and to start production by December 2024. When all three phases are complete, the new production line will have a yearly capacity of 58,000 microLED wafers (we do not the wafer size at this project, but we estimate these are 8-inch wafers). It is not clear from the reports, but this production line may also produce mini LEDs, not just microLEDs.

We're happy to interview Yenrich, as part of our series of interviews with MicroLED Industry Association members. Yenrich, spun-off from Epistar and now part of the Ennostar group, develops mini-LED and micro-LED packaging. The company is focused on direct-view displays, both miniLED based and microLED based.

Hello! Can you introduce your company and technology?

Yenrich, a member of Ennostar, focuses on the development of Mini/Micro LED technology and products for fine pitch displays and provides customers with integrated solutions of front-end chips and back-end system applications.

Q: Can you say why you joined the microLED association and what it is you hope to achieve?
1.    Learn the latest Mini/Micro LED technology and information from the MIA and get more correct product roadmap in this field
2.    Understand the needs of Micro LED for AR/VR and automotive applications and technology

This is a sponsored post by STAr Technologies

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BOE announced that it has developed a new high-transparency mini-LED directview display, that offers a transparency of 65% and a brightness of over 1,000 nits.

BOE says that it achieved this high performance by optimizing the pixel circuit and designing a new pixel structure. BOE also used a new innovative design for the transparent area (it achieved a transparency of 95% in the transparent areas) and an optimized wiring structure.

China-based LED producer Jucan Optoelectronics announced that it plans to raise 1.2 billion yuan ($178 million USD) to expand its mini-LED and micro-LED R&D and production projects.

We do not have more information on this project, and Jucan's exact plans to produce microLED chips.

Kulicke and Soffa Industries (K&S) announced that it has received two purchase orders, from two separate customers, for its LUMINEX, a disruptive laser-based mini and micro LED die-transfer solution.

K&S says that its highly flexible system is capable of single die transfer, multi-die transfer and mass transfer, supporting sorting, mixing, re-pitching and placement process steps. The broad flexibility of this system addresses the growing advanced display value chain and supports needs of LED, OSAT, panel and display suppliers.

China-based Nationstar Optoelectronics announced a new "cooperation agreement" with Huawei for the development of mini-LED and micro-LED display technologies.

The two companies will, it seems, conduct "in-depth innovation" in these fields, and will open a joint innovation center. The company did not disclose any more details regarding the microLED project.

Taiwan-based panel semiconductor provider PanelSemi Corporation launched the world's first flexible active-matrix Mini-LED display at CES.

The display, called Primary, is a 55-inch HD resolution (1.2 mm pitch) miniLED direct-emission that is highly flexible, light (1 Kg for the whole display) and thin (1 mm thickness). It can be flexed to a concave, convex, s-curve, cylinder, and rollable shapes and four displays can easily be joined to create a 110-inch display. PanelSemi says that Primary is highly efficiency, and 4 hours of use can be driven by a single 10 K-mAh power bank.