Sunlight Technology

Sunlight is the ultimate pursuit of the artificial light source

The sun essentially provides complete and homogenous spectral radiation in the visual wavelengths at any time of the day, it offers natural light for comfortable sight and full-spectrum emitting for healthy biological effects, which makes the sun the most ideal light source, while theories of light-emitting of the artificial light sources, including the LED which is generally combined by the blue semiconductor die with phosphors, are far away from sunlight (blackbody radiation), therefore it is visualized to observe that artificial light sources cannot approach the real sunlight in spectral level, thus are unnatural effects.

Yujileds® sunlight technology, up to 99% similarity effectively

sunlight technology

Yujileds® sunlight technology gives innovative and revolutionary solutions providing unprecedented Spectral Power Distribution (SPD) with ultra-homogeneous features. It mimics the natural light spectrum up to 99% similarity to the spectral engineering level, where a standard LED spectrum generally misses significant radiance and only constitutes less than 50% of the sunlight spectrum.

Simulating the spectrum is the essence of simulating the real sunlight, our technology makes it possible to “clone” the gene of the sun even if the luminescence principle is different, and the harmful UV (ultra-violet) and useless IR (near infrared) are cut out of the spectrum.

Higher than high CRI

99 CRI

As the new generation of high CRI LED lighting, and by mimicking the natural light spectrum, Our LED performs outstanding color rendition than the standard LED and high CRI LED.


Our sunlight spectrum technology becomes disruptive again to the market when high CRI LED lighting gets widespread. Up to 99 CRI, we surpass our high CRI technology by ourselves, it is not just a super-high CRI performance, but the individual Ri is steadily up to 100, making the color truly vivid without losing any details.

CRI 99
Super TM-30

Superlative TM-30 metric valuation

With the metric of TM-30, Yujileds® sunlight LED presents even more extraordinary advantages. When CRI cannot finely distinguish color quality especially the metamerism phenomenon happens, the comprehensive evaluation methods of TM-30 provide the insightful results of the color metrics. Fidelity index (Rf) achieves 98, gamut index (Rg) achieves 100, accurate color vector, minimal chroma/hue shift, uniform and high fidelity of all 99 color samples, indicating the high-performance of the sunlight simulation.

100 TLCI

The color rendition and accuracy performance is not only for human eyes, but is also valuable for “electronic visual” like the camera sensors. Yujileds® sunlight LED achieves up to the full score of 100 TLCI (The Television Lighting Consistency Index) with zero incorrectness of the chromas, making it the ideal light source for the professional use of photography, television, broadcast, studio and cinematography lighting, it also indicates that the feature of a homogenous spectrum is significant to the non-visual, optical-electric devices.

TLCI 100

Ideal simulation models of CIE illuminant

For industrial use, the CIE illuminants (A / D50 / D65) are frequently required as references thus the lighting environments desire as close to the standard illuminants as possible. However, standard LEDs are always far away from these illuminants that cannot get a promising result and it is never about just increasing CRI numbers because the spectral quality is the vital factor for visual appraisal and measurement of color (e.g. ISO 23603, CIE S012/E).

Thanks to our deep research and development of the correct spectra of each color temperature, it is not surprising to receive positive performance and feedback based on different industrial standards and measurements. 

simulation of CIE illuminant

Improved luminous efficacy

improved efficacy

Luminous efficacy is important whether for energy saving or simplifying the design of a lighting system, whereas the spectral quality is contrary to efficacy. When the spectrum covers a wider wavelength and equally distributes at each nanometer,  less radiance will be involved in the effective lumen sensitive range relatively, then the luminous efficacy is difficult to be promising.


We optimize the LED die binning, and with the enhancement of Yuji phosphor solutions, this inevitable phenomenon is suppressed effectively that our sunlight spectrum LEDs reach the same efficacy or even surpass than a standard LED.

Introduce the product series

As the experts and pioneers in sunlight simulation technology, we focus on the elaborate solutions so deeply that we are the only one providing different concepts of full-spectrum LED products. Specified to 10nm distinction, our LEDs can be allocated to different applications precisely. Due to the difference in the spectrum, the differences in these solutions are reflected in many aspects. For this reason, we simply gave the main difference between the three mainstream products series (APS/AP/VTC), and summarized them in the following table:

guidance of sunlight spectrum LED

VTC Series

AP Series

APS Series

More than the VTC / AP / APS series LEDs

The story will not just end with the VTC / AP / APS series LED with natural light and full-spectrum features, for specific applications, we develop specialized series LED, extending the spectrum coverage to UVA, near-infrared, or halogen-like that could start from 360nm and end to 1000nm, achieving the simulation of the sunlight or electromagnetic spectrum to a broader and precise scope.

Measurement from experts

Delta optical thin film


Delta optical thin film focuses on complex optical filter technology for more than 50 years and it is one of the first companies to produce ultra-hard-coated optical filters. Today, the design and manufacture of high-performance fluorescence filters are the main business, and with the in-house design and production tools, Delta continues to meet the needs of discerning OEM customers.

During the evaluation of Yujileds® sunlight technology LEDs, Delta Linear Variable Bandpass Filters (LVVISBP) is applied for the measurement. The measurement procedure is as simple as putting the filters in front of the light sources, but the phenomenon is noticeable by naked eyes directly, especially when compared to a fluorescent lamp and standard LED. Spectrum theory sometimes is difficult to understand but this measurement perfectly explains the relationship between spectral and visual differences. Every detail in the spectrum could be presented in the result after the filters, and eventually the importance and value of a full-spectrum LED should be widely accepted.

Delta optical thin film

Opto-transmitter Environmental Protection Technology e.V. (OUT e.V.)


Opto-transmitter Environmental Protection Technology e.V. is an industrial research facility for the promotion of science and research in the fields of micro and optoelectronics, microsystems technology, medical technology and biotechnology, sensor technology and safety technologies and the business is not for profit.

OUT e.V. processes the detailed and impartial measurements on Yujileds VTC series LED for a comprehensive performance of different working temperatures and electrical currents. Apparently, the photoelectronic parameters perform stably which makes the VTC series LED adaptive for wide applications.

Opto-transmitter Environmental Protection Technology

Indie Cinema Academy


Indie Cinema Academy is a professional organization focusing on providing the education of film school level concepts and techniques to bring the audience’s video projects up to the level of the masters. Indie Cinema Academy makes the skills accessible and explains every step of the way the hows and whys of the camera and lighting choices.

Lighting plays the decisive role in film shooting and Indie Cinema Academy has done a great job of collecting all LED databases from the market to compare the color rendition quality and rank the different brands or products. CRI and TM-30 are both evaluated considering the rationality and impartiality to the professional level. Yujileds® sunlight technology LED gets the runner-up with CRI Ra 98.4, CRI Re 97.5, TLCI 99.5, CQS 97, Rf 97 and Rg 100, only defeated by the sun.