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End Flicker: What You Can’t See CAN Hurt You

Energy Focus Blog


  1. What is Flicker?

    Flicker in LED lighting occurs as a result of the LED driver converting AC power to DC power. Modulating the current to produce lower flicker is the challenge that all drivers have, and Energy Focus has made a commitment to reducing flicker in all future products.

    Many of our competitors’ LED products on the market today continue to introduce high flicker rates into indoor environments. Even though the human visual threshold is about 50 hertz, if a light source is flickering faster than 50 cycles per second, this imperceptible flicker can still have a negative impact on health, wellness, and productivity. Without question, from our school children to patients and medical teams in hospitals, flicker in lighting can have a profound effect on our health and productivity.

    To better understand flicker’s potential for adverse consequences, it’s important to distinguish between the various classifications of flicker in lighting:

    • Visible flicker is the modulation of light, periodic or intermittent, which most humans can see as a change in the light output.
    • Stroboscopic flicker is the periodic modulation of light due to the characteristics of the power source being used. Stroboscopic flicker is perceptible when the light source or end user’s head moves. Stroboscopic flicker can be either visible or invisible. Even in ideal conditions, or with normal usage, traditional light sources can also exhibit stroboscopic flicker.

The Facts on Flicker

  • Flicker can induce seizures in people with photosensitive epilepsy.
  • Flicker can contribute to headaches, eye strain, and fatigue.
  • Flicker is a visual trigger that studies show can account for 38 percent of reported migraines.
  • Flicker can negatively impact individuals with Autism Spectrum Disorder due to their visual hypersensitivity.
  • Flicker can cause the stroboscopic effect, which can pose hazards when using fast-moving machinery.
  • Flicker can render barcode scanners ineffective, as scanners won’t function under flickering lights, creating issues for retailers.

Energy Focus is committed to spreading the message about flicker, and emphasizing the importance of eliminating flicker in lighting through our 2018 campaign, “End Flicker. What You Can’t See CAN Hurt You.”

What Energy Focus is Doing to Combat Flicker in Lighting

To ensure our LED products offer the most extensive health and wellness benefits over conventional lighting, Energy Focus has made a commitment to reducing flicker in all tubular products. To underscore just how serious we are about eradicating flicker, Energy Focus has developed the first UL Verified low optical flicker (less than 1 percent) lighting on the U.S. market. Throughout 2018, we are challenging our competitors to meet the same standards we are, by making the reduction in flicker a top priority for their products, too.

The Energy Focus RedCap™ Emergency Battery Backup is a first-in-class emergency lighting solution from the industry’s most innovative company.

The RedCap™ is a high-performance, self-ballasted TLED, providing 150 lm/W efficacy. The RedCap™ also integrates rechargeable batteries, without the need for an external charger, enabling an 11- watt lamp to illuminate for the electrical code-required 90 minutes egress, equivalent to legacy fluorescents in the event of a power failure.

With the RedCap™, your fluorescent fixture can be retrofitted for normal operation and emergency backup, without the need for any bulky external batteries or emergency ballast. Since everything is integrated into one lamp the wiring is simple, requiring fewer wires compared to conventional emergency systems: one end — the “input” end — of the lamp is wired for normal, switched operation. The other end — the end with the red endcap — is wired to charge the batteries as needed, even when the lights are off, and can sense power loss, which triggers the lamp to go into emergency mode.

Not only are the integrated batteries a better match to the functioning load, the RedCap™ reduces the costs and labor time of an emergency solution and improves aesthetics over other conventional emergency lighting products. Designed to keep the customer’s safety and security at the forefront, the RedCap™ is not only the first UL Classified TLED lamp with an integrated emergency power circuit in the market, but also complies with OSHA, NEC, IBC, NFPA, and IFC emergency lighting regulations.

The RedCap™ is also DLC listed to verify its performance. The Energy Focus RedCap™ includes a 5-year warranty, which includes the batteries and provides coverage from one end of the tube to the other, for total peace of mind. This makes replacement and renewal as simple as changing a lamp, ensuring that the continued maintenance of your emergency lighting system is a minimal burden. Combining innovative technology, simple installation and regulatory compliance, Energy Focus’ RedCap™ provides the difference between the lights coming on in an emergency or leaving a facility and its inhabitants in the dark.

This article was featured originally in LIGHTFAIR International 2018 publication, “Lighting News”.

If you are interested in learning more about our RedCap™, please call our customer service agents using our online form.