Fighting Flicker: The Impact of Flicker in Lighting...19. Mohammadizadeh et al. “Is the...

Fighting Flicker: The Impact of Flicker in Lighting Light, Health and the LED Revolution February 15th, 2018

© 2017 Energy Focus, Inc.

Who is Energy Focus? Healthcare Education Military Government Retail Industrial Parking Office

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Energy Focus is a manufacturer and provider of LED Lighting retrofit technology for the most demanding applications where performance, quality and health really matter.


From Energy Focus

Laszlo Takacs Chief Technology Officer John Davenport Chief Scientist Yumi Alanoly Product Manager, Marketing

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Agenda 1.  Theory Behind Flicker 2.  Common Flicker Misconceptions 3.  What Can Be Done About Flicker 4.  Questions and Answers

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© 2017 Energy Focus, Inc. 5

How Lighting Affects Us Our eyes let light in to trigger neurological processes. Visually

•  2/3 of electrical activity in the brain comes from vision •  50% of human brain used for vision3

Physiologically •  Hormone suppression or activation via light4 •  Circadian Rhythm Regulation5

Psychologically •  Mood, emotion6 •  Cognitive Behavior7


The Human Eye 101 o  We see when light bounces off

objects, enters the pupil, and is focused by the lens onto the retina.

o  Rods and cones in retina talk to visual processing part of brain.1

o  More receptors in eye have nonvisual response (go talk to other parts of brain).2

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FLICKER: In addition to wavelength and intensity level, our bodies via our eyes are sensitive to rapid light intensity variations


Optical Flicker WHAT YOU CAN’T SEE, CAN HURT YOU


Flicker: Flicker at 120 Hz slowed to ~ 2.5 Hz

Energy Focus YouTube Video: https://www.youtube.com/watch?v=6k_3D2oLP7E

Energy Focus < 1% Competitor 1 Competitor 2


Understanding Optical Flicker

According to IES (Illumination Engineering Society), flicker is the rapid variation of light source intensity. Potential Flicker-Induced Impairments include*: o  Seizures (from epilepsy, traumatic brain injuries,

concussions, etc.) o  Headaches, fatigue, blurred vision, eyestrain o  Migraines o  Reduced visual task performance o  Increased autistic behaviors, especially in children o  Distraction

Flicker free lighting reduces or eliminates these symptoms.

“Flicker—Understanding the New IEEE Recommended Practices” (http://energy.gov/sites/prod/files/2015/05/f22/miller%2Blehman_flicker_lightfair2015.pdf), DOE & Pacific Northwest National Laboratory


Why It’s Important – Application Example



o How much flicker output does an incandescent lamp produce?

o How much flicker output does a fluorescent lamp produce?

o How much flicker output does an LED lamp produce?




Conventional light sources typically <50%



“Deep Flicker” is possible with LED


LED Light may have 100% flicker


Light and Health

Flicker o  Difficult to see in fovea (small

depression in the retina of the eye where visual acuity is highest) above 50Hz5

o  But from eye to brain goes like a strobe! •  Headaches, epilepsy, “Scotopic

Sensitivity Syndrome”6

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The Wellness Factor with LEDs

•  For Staff o  Visual acuity and lighting quality is critical for tasks

from surgery to reading charts o  More comfortable work environment

•  For Patients o  Promoting wellness (no hazardous materials, no

UV, no flicker) o  Better spectrum of light for better sleep/wake

cycles o  Creating a pleasant environment, better for healing

•  For Facility Administrators o  Dramatically reduced energy usage and

maintenance costs o  Lower costs and a reduced carbon footprint


Benefits of Flicker-Free LED Technology

Even modest Flicker can be an issue… Substropic flicker in lights, or flicker that is present but strobes faster than we can “see”, has a negative impact on our visual processing. To the average person, this may result in headaches or discomfort after exposure, but to people with special needs that experience visual hypersensitivity, such as those on the Autism Spectrum, this same flicker can be disruptive to their everyday activities. Flicker free lighting reduces or eliminates these symptoms.

Not all LED products are Flicker free.



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1.  All LED lamps are flicker free

2.  As long as I don’t visibly see flicker it cannot hurt me

3.  My lights do not dim therefore they do not flicker

4.  What is the relationship between frequency and flicker?

Common Flicker Misconceptions

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The LED Difference: Removing Flicker Fluorescent lamps and some LEDs flicker*- can vary greatly by lamp and manufacturer

* Department of Energy, Flicker Fact Sheet, PNNL-SA-94791, March 2013

The stroboscopic effect is just one of many consequences of flicker. The lamp used for the image on the left does not flicker and thus the moving object is a smooth blur. Because it does flicker, the lamp used for the image on the right appears to create multiple instances of a moving object.


Recommended Limits of Flicker vs. Frequency

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o  Energy Focus’ technology measures safely within the green region of the IEEE’s recommended flicker limits

o  Green Zone is the “No Observable Effects”

o  Yellow Zone is the “Low Risk” area



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Achieving Flicker-Free LED Technology*

Older Tech New Technology TLEDs

Vs

© 2017 Energy Focus, Inc. 23 2/15/18

Providing Mechanically-Compatible Environments

o  Flicker-Free §  Flicker can interfere with barcode scanners and

video/photography equipment o  Low THD

§  Avoids voltage distortion and electronic pollution that could interfere with medical equipment

o  High PF & Inrush Current Avoidance §  Eliminates issues of ampacity limits in wiring

and utility penalization charges o  Low EMI

§  FCC & CISPR guidelines for low EMI & RFI that could cause disruption to electronic devices and wireless communication (including medical equipment)


Better Quality of Light is possible with LEDs … •  Better for Vision

o  White light comes in a variety of color temperatures (3500K warm, 4000K neutral, 5000K bright). The higher the color temperature, the brighter the light is perceived to be.

o  Bright white light with enough blue content is important for suppressing melatonin during waking hours. Higher color temperatures achieve this.

Fluorescent

Incandescent

LED

Sunlight

Better for Circadian Regulation o  Patients and staff inside of hospitals need enough light to control

this hormonal process to stay awake during the day.

o  It is equally important to avoid light at night in patient rooms. o  Healthy sleep/wake cycles are associated with better moods,

more focus, healthier immune systems, and lower BMI

… if you demand LEDs with low flicker


UL Flicker Verification



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Questions and Answers

Join the LED “Flicker-Free” Revolution!


Contact Us Email: [email protected]

Phone Number: 800-327-7877

energyfocus.com

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Thank You!

Energy Focus Inc. Flicker - What You Can’t See CAN Hurt You

© 2017 Energy Focus, Inc. 31 2/15/18

Sources 1.  Edison Tech Center. “The Fluorescent Lamp” http://www.edisontechcenter.org/Fluorescent.html. 2.  United States Environmental Protection Agency “Health Effects of Mercury Exposure” http://www.atsdr.cdc.gov/mercury/docs/HealthEffectsMercury.pdf. 3.  Roberts, Joan E. “Ultraviolet Radiation as a Risk Factor for Cataract and Macular Degeneration” Eye & Contact Lens Vol 37 No 4. 2011. 4.  Pokorny et al. “Aging of the human lens” Applied Optics Vol 26 No 8. 1987. 5.  Ellis et al. “Auto-tuning daylight with LEDs: sustainable lighting for health and wellbeing” Drexel University and Philadelphia University. http://

www.bauarchitecture.com/research.daylightleds.shtml 6.  Irlen Institute. “What is Irlen Syndrome?” http://irlen.com/what-is-irlen-syndrome/. 7.  Graph 1: Popular Mechanics: The Ultimate Light Bulb Test http://www.popularmechanics.com/technology/gadgets/reviews/g164/incandescent-vs-compact-fluorescent-

vs-led-ultimate-light-bulb-test/. 8.  US Department of Energy “Solid-State R&D Plan” May 2015. 9.  Lucas, Robert J et al. “Measuring and using light in the melanopsin age” Trends in Neurosciences Vol 37 No 1. 2014. 10.  Holzman, David C. “What’s in a Color? The Unique Human Health Effects of Blue Light” Environmental Health Perspectives Vol 118 No 1. 2010. 11.  Hawes, Breanne K., et al. “Effects of four workplace lighting technologies on perception, cognition, and affective state” International Journal of Industrial Ergonomics

Vol 42. 2012. 12.  Meesters, Ybe et al. “Low-intensity blue-enriched white light (750 lux) and standard bright light (10000 lux) are equally effective in treating SAD. A randomized

controlled study” BMC Psychiatry. 2011. 13.  US Department of Energy. “Flicker” Building Technologies Office Solid-State Lighting Technology Fact Sheet. 14.  Loew et al. “Symptoms of Meares-Irlen/Visual Stress Syndrome in subjects diagnosed with Chronic Fatigue Syndrome” International Journal of Clinical and Health

Psychology Vol 14 ppp87-92. 2014. 15.  Ameritech Energy. “Flicker Free – Important Design & Buyer Information” Solid-State Lighting Technology Fact Sheet. http://www.energyfocusinc.com/lighting-and-

your-health/ 2014. 16.  Roberts, Joan E. “Light and Immunomodulation” Annals New York Academy of Sciences. 2000. 17.  Rensselaer Polytechnic Institute. “Chapter 16: Human eye sensitivity and photometric quantities”

http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/Sample-Chapter.pdf 18.  Salva et al. “Circadian rhythms, melatonin and depression” Cur Pharm Des vol. 17 no. 15. 2011. 19.  Mohammadizadeh et al. “Is the light-emitting diode a better light source than fluorescent tube for phototherapy of neonatal jaundice in preterm infants?” Adv Biomed

Res vol. 1 no. 51. 2012. 20.  World Health Organization. “LED phototherapy for neonatal jaundice” Compendium of innovative health technologies for low-resource settings 2013. 21.  Sawyer. “Phototherapy for Jaundice” Medscape http://emedicine.medscape.com/article/1894477-overview 2013. 22.  Smil, V. 2014. The long slow rise of solar and wind. ,Scientific American 282 (1):52-57; EIA 2013 Energy Book; “Lighting The Way 2013”, McKinsey Inc.

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