Application status of luminescent materials for high-quality white LED light sources

With the accelerated penetration of white LEDs in the field of lighting, the market's demand for quality white LED light sources is also getting higher and higher, especially in indoor lighting, the focus on white LED light sources has changed from the initial pure pursuit of "high brightness" "Converting to "high quality" that takes into account light and color performance such as color rendering index and color temperature, and even pursuing full-spectrum lighting similar to sunlight, domestic and foreign packaging companies have accelerated the development of full-spectrum LED products. At present, there are mainly two types of full-spectrum LED implementation methods: multi-chip type and single-chip type. Among them, the single-chip type has become the first choice for packaging companies due to its simple implementation, low cost, and more continuous spectrum. The single-chip implementation is further divided into blue-light chip technology (blue-light chip + multi-color emission phosphor) and ultraviolet/near-ultraviolet chip (ultraviolet/near-ultraviolet chip + multi-color emission phosphor) technology. In blue-light chip technology, there is a serious lack of spectrum in the blue-green part of the device spectrum, and it is theoretically difficult to achieve high-quality full-spectrum healthy lighting needs. At present, the ultraviolet and near-ultraviolet chip technology in the third-generation semiconductors that are being developed by the country is becoming more and more mature, which makes the ultraviolet/near-ultraviolet chip technology become the preferred technology for full-spectrum lighting.

The technology of various color phosphors excited by blue light has become mature, but most of these phosphors cannot be excited by violet light efficiently. At present, there are many researches on green, yellow and red phosphors for excitation of ultraviolet/near-ultraviolet chips. However, the common problem is luminescence. The efficiency is low and it is difficult to meet practical applications. The development of phosphors suitable for high-efficiency excitation of violet light, broad-band emission, and low mutual absorption between phosphors of various colors has become a research focus in the industry, and is also an important force for my country to achieve intellectual property breakthroughs in the field of lighting in the future. Therefore, in the field of full-spectrum lighting, grasping the development opportunities and trends of high-energy and short-wave third-generation semiconductor technology, and developing new luminescent materials for it, especially new phosphors suitable for ultraviolet/near-ultraviolet chips, are important to achieve green and healthy lighting opportunity.