With the rapid growth of modern energy-saving lighting […]
With the rapid growth of modern energy-saving lighting technology in our environment, the understanding of its impact on biology and even technology is also growing. With the rapid development and assimilation of LED lighting, there is often no clear standard, which may cause lighting flashing and bring adverse effects. Many organizations, including international standards bodies and regulators, and interdisciplinary industry professionals are working to measure, understand and properly manage flickers.
First, why does the LED light source flicker?
1. LED light source is a different story. Based on semiconductors, they respond rapidly to power changes, and common power systems and drivers may produce too much flicker.
2. Scintillation has existed since the invention of AC power source. The change of power supply stage produces the corresponding fast periodic change of light radiation and illumination intensity or brightness. Traditional incandescent lamp lighting system is affected, but the effect is not obvious, because the filament response to power changes is relatively slow. Other light sources, such as fluorescent tubes or other discharge lamps, have fast response times, so the changes of observers are more obvious.
2. The effect of scintillation on us?
1. Scintillation affects workplace safety and productivity, comfortable living space, and according to recent research, our overall health and emotional health. For example, from a safety point of view, the fast-rotating elements in the operator's vision do not seem to move very fast, or stop because of too many flickers. From the perspective of photobiology, prolonged exposure to excessive scintillation leads to neurological problems, such as headache, migraine, and even epilepsy.
2. From a technical point of view, flicker will strongly affect the lighting of digital image shooting, especially in TV studios and stadiums. Strict broadcasting requirements require appropriate power supply systems to avoid camera image artifacts, especially stroboscopic effects during high-speed capture and slow playback.
3. How to limit flicker?
1. In LED light sources, flicker can be reduced by proper design and power filter, for example by using more capacitors. Alternatively, a high-frequency voltage converter can be used. Through the LED dimmer, the light intensity can be adjusted in many ways. As some LCDs do, switching from pulse width modulation to current adjustment also reduces flicker.
2. Manufacturers use several different technical solutions to limit flicker. But what is technically possible does not always translate into a perfect finished product. Changes in power system design may increase size and cost - not always the manufacturer's choice. As a result, the flickering features on the market do not match the expectations of customers or designers. Devices defined as having the smallest flicker can actually be driven by high frequencies invisible to the human eye, or even by television cameras. Without proper measurements and standards, statements such as "no flicker" may be more advertised than quantified attributes.
Scintillation is an old phenomenon that needs new consideration in the era of LED lighting. The industry has made progress in quantifying scintillation and its measurement. Many industries and global standards organizations are in urgent need of further understanding and quantifying how scintillation affects humans and other biological forms in a variety of ways. Meanwhile, progressive instrument manufacturers such as GL Optic have developed methods to quantify certain scintillation characteristics accurately and repeatedly. There is no doubt that in the future of solving the scintillation problem, the bright burning will have positive results for all.