GILE 2017 REVIEW: What happend to light quality?

Starting from June 9^th 2017, the 22th Guangzhou International Lighting Exhibition 2017 (GILE 2017) held at China Import and Export Fair Complex gathered over 2,000 exhibitors from 30 countries. Within 18 halls and over 2000 booths, extensive knowledge, up-to-date applications and cutting-edge technologies of LED lighting were presented to all visitors, no matter professionals in the industry or just fans of LED lighting.

YUJI visited GILE 2017, for a glance at the latest applications of LED light sources and update of our peer manufactures. Here is what we got:

In terms of lighting fixtures, LED bulbs were much less seen this time, while application- and design-compatible fixtures, such as panel lights and linear lights, were increasingly accepted by the market and became the mainstream. Almost all light exhibitors were presenting these or similar types. Luminous efficacy, a concept that used to be popular over the past several years, was seldom mentioned this time. Instead, concepts like smart control, dimmable & programmable light, anti-glare, super slim and frameless design, are the new hot issues this year. This indicates that due to the development and popularization of LED technologies, its property of high efficacy is widely known and customers’ attention are now drawn by manufacturers to other experience than just illumination. Unfortunately, however, light quality, the most critical index for a lighting fixture, was seldom spoken of. In evaluating color quality, Ra (average of R1-R8, color rendering abilities of eight low saturated colors), was still abused, where CRI (average of R1-R14, color rendering ability including six other saturated colors) should be used. Most lighting fixtures had only 80 Ra values, and their R9 (ability to render the red color) were much lower than the average CRI, some of which were even below 0. There are definitely reasons for such low light quality (80 Ra), which we believe are:  

1. Number of LED package manufactures is insufficient, making it difficult for fixture manufactures to obtain high CRI light sources;
2. Reason 1 causes high cost for high CRI light sources, thus losing its price advantage;
3. Compared to other catchy concepts such as smart control, high CRI is not popularized enough. Customers don’t fully understand why color rendering ability matters, so manufacturers lack the driving force to improve CRI.

In terms of LED packages on the GILE, applications in light solidification, sterilization and horticulture lighting are visibly intensifying. Almost all the well-known brands had exhibits in these fields. However, as mentioned above, little progress was made to improve the color rendering ability of white color packages. Currently most LED package manufacturers are dealing with CRIs about 80, and only a little portion are producing packages with 90+ CRI. When it comes to 95+, there are only a few on the list. Some of them are capable of large quantity production, yet the CCT range can only be under 5000K. Besides, when talking about color rendering ability, most manufacturers are still using Ra as the index, when the ability to render saturated colors (esp. R9) is ignored. According to our spot tests on several exhibited packages, some could achieve 95+ in Ra, but other indices, such as R9, was not satisfying.

Below is a comparison among two well-known brands’ packages and the counterpart YUJILEDS^TM product in color rendering performance:

The chart reveals that most LED manufactures are not providing enough information about high CRI, and that YUJILEDS^TM prevails in high CRI products. Apart from the manufacturing technologies, properties of the raw materials are the essential factors for CRI of white LED packages. In our previous posts, we discussed differences and impacts of raw materials of an LED package. (Go check it if you are interested: https://store.yujiintl.com/blogs/high-cri-led/181003783-why-high-price-for-high-quality-led-products.) At last, we were glad to see a manufacturer promoting similar concept with YUJI—full spectrum LED. Yet, our test result showed that their exhibits were closer to YUJILEDS^TM BC series. Compared to YUJILEDS^TM VTC series, they still lack the royal blue and violet part in the spectrum.

According to our visit to the GILE 2017, few manufactures are persistently dedicated to white LED light quality and color rendering ability improvement like YUJI. For LED manufacturers and professionals, to promote the importance of light quality, of LED lighting fixtures, and of reasonable choices, there is still a long way to go.