Canon U.S.A. Inc. has announced that its parent company, Canon Inc., has developed a quantum-dot ink with a perovskite structure (perovskite quantum-dot ink) as a material for next-generation quantum-dot displays and has successfully demonstrated its practical durability for the first time in the world.

The performance and image quality of display devices continue to rapidly improve, and toward this end, one such approach that is gaining momentum is applying quantum-dot technologies (QD) to meet the need for displays with higher image quality.

Quantum dots are semiconductor nanocrystals that measure only a few nanometers in diameter and can emit light with high brightness and high color purity. Displays with quantum-dot technology are attracting growing attention due to their wide color gamut that makes possible high visual expressiveness. Therefore, quantum dots for display are sought to achieve higher color purity and higher light utilization efficiency. In addition, though cadmium (Cd) has thus far been the preferred material for quantum dots, due to environmental concerns, there is a growing interest in Cd-free materials.

With these requirements in mind, Canon has focused on the development of perovskite quantum-dot inks. Perovskite quantum dots are considered an effective Cd-free approach other than InP (indium phosphide) quantum dots. In terms of color purity and light efficiency, many see perovskite quantum-dots as a promising material capable of contributing to high brightness, a wide color gamut and high resolution. However, poor durability has thus far been a barrier to practical use.

To address the issue of durability, Canon is leveraging its proprietary technologies nurtured through development of ink and toner for printers. The company has established a unique method to form a protective shell on quantum dots, thereby achieving practically durable perovskite-dot ink with retained color purity and light usage efficiency.

InP quantum-dot ink covers 88% of the color gamut based on the ITU-R BT. 2020 recommendation, while Canon's perovskite quantum-dot inks can cover 94% of the gamut. In addition, the high efficiency of light use is expected to reduce power consumption of quantum dots by approximately 20% compared to conventional technology.

Canon's quantum-dot inks have the potential to help realize next-generation OLED displays with ultra-high definition, such as quantum-dot 8K displays, a technology that thus far has been unachievable.

The results of technological development of the ink and the technology for mass production of high-quality perovskite quantum dots were announced on May 26, 2023, at SID Display Week 2023 in Los Angeles, California.