Micro LEDvs OLED

Samsung Display demonstrated a new OLED microdisplay at K-Display 2024, a 1.3" 12,000 nits 4000 PPI display. It is not clear whether this display is a direct-emission display, or one that uses white OLEDs with color filters.

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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.

Micro LEDdisplay

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.

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.

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.

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.

Mini LED

With more and more mature technology for Mini- and Micro-LEDs fabrication, manufacturers are gearing up for the production phase and critically looking for more test efficiency and fast testing for the optical devices. STAr Technologies, as the leading Mini- and Micro-LEDs tester supplier continuously develops measurement technology to enhance optical testing capabilities and parallel test efficiency and to achieve cost-effective high-volume production.

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.

Mini LEDvs OLED

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.

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.

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.

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.

Japan's Semiconductor Energy Laboratory (SEL) demonstrated its own OLED microdisplay technology at Displayweek 2024, a 1.5" 3840x2880 (3207 PPI) display that achieves a brightness of 15,000 nits by using a tandem architecture and a direct-emission design.

Samsung MicroLED

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.

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

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.

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.

STAr’s Unicorn-LAIT II tester is designed to meet diverse industry requirements and to ensure accurate and reliable measurement results in the shortest amount of test time, based on an integrated parallel test architecture. The tester is ideal for electrical, optical measurement, driver functionality, RGB testing, etc. The tester is equipped with high efficient Dark and EMI Shield test environment dedicated to LED and Laser Applications. The system can be upgradeable with an autoloader for a fully automatic test with a cassette.

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miniLED OLED

Micro LEDTV

During CES 2025, Samsung Electronics demonstrated a 98-inch 8K microLED-backlit LCD TV, branding it as RGB MicroLED TV. This is not a true microLED TV, as it is not emissive, but unlike other LED- and miniLED- backlit LCDs, this one uses smaller red, green and blue microLEDs.

Samsung Display's CEO, Choi Joo-seon, said during the conference that SDC will soon commercialize OLED microdisplays based on eMagin's direct-patterning deposition technology (SDC acquired eMagin in 2023). Choi says that the price of OLED microdisplays is an important differentiating factor. Last week Omdia estimated that the price of OLED microdisplays is set to decline sharply in the near future.

Samsung is accelerating its OLED microdisplay plans, as the company hopes to supply displays for companies such as Apple and Microsoft . In fact, Microsoft has reportedly signed an agreement with Samsung Display for the supply of OLED microdisplays for a 2026 MX device.

Micro LEDmonitor

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Samsung now says that it plans to launch this new TV, at a size of 115-inch, later in 2025. This will be Samsung's most premium LCD TV. One of the main advantages over its current miniLED-backlit LCDs, is the use of red, green, and blue microLEDs, rather than blue miniLEDs and color-conversion (QD and phophors) technology to create white-emitting LEDs. This should enable a larger image gamut. The microLEDs may also contribute to a higher contrast compared to the bigger miniLEDs, as there will be better dimming zone control.

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 field2.    Understand the needs of Micro LED for AR/VR and automotive applications and technology

In May 2024, during SID Displayweek, Samsung unveiled its a 1.03" direct-emission OLED microdisplay. At the same trade show, LGD showed an impressive 10,000 nits 1.3" 4K (4,175 PPI) OLED microdisplay that uses new OLED materials and LG Display's micro lens array (MLA) to increase brightness by about 40% compared to LGD's previous generation microdisplays.