Presented by NAILD
With Mark Baker
8/28/23 – Lighting Episode 323 (Full Version) – Mark Baker 51:31
Oh boy. Here comes another curve ball for the industry. LEDs came along in the early 2000’s. They emitted light. They were energy efficient. What could be bad? Ask Mark Baker who’s highly sensitive to certain LED lights. And there are people worse off than him who cannot neurologically tolerate the type of radiation emitted by LEDs. Imagine if you couldn’t go to a store or walk under street lights lest you get dizzy, acquire a migraine or fall into an epileptic episode. There are thousands of people who can’t leave their house, and now can’t even replace their light bulbs with incandescents. Mark Baker is the President of The Soft Lights Foundation, a non-profit organization that advocates for the protection of people and the environment from the harms of visible radiation emitted by products that use Light Emitting Diodes. Mark is the primary author of a primer on the differences between a curved surface emitter and a flat surface emitter. His co-authors include subject matter experts in the fields of physics, engineering, medicine, and light pollution.
Your Resources
– SoftLights.org
– The Soft Lights Foundation on Facebook
– Ban Blinding LEDs on Facebook
– Ban Blinding Headlights and Save Lives Campaign
– National Association of Innovative Lighting Distributors (NAILD)
Brilliant podcast revealing the very hazardous nature of LED technology and the devastating effect it is having on health acutely, chronically.
For me it is the intensity and piercing brightness, especially the car lights. I had some LED lights at home quite different from incandescent and halogen, they were warm white but as mentioned no red in it like incandescent and halogen have. As for visual acuity. It has the opposite effect as there us either darkness and bright. Cones and rods at last I’ve heard it stated about the invisibility of pedestrians. I’ve heard that people in Singapore have lost their night vision, is this true. Far fewer insects, fewer birds. No-one cares.
One day the worlds of wasteful pleasure will disappear
While I applaud the effort to reduce glare and flicker, some of the information offered was simply incorrect.
Light emitted by any surface overlaps whether the surface is flat or curved. If light from a curved surface didn’t overlap, we would see the sun as a single point of light, not an object that subtends about 0.5 degrees, The discussion about LEDs being flat light sources also ignores the actual construction and operation of LEDs.
Roughly 90% of the lumens emitted by a white LED are generated from phosphor particles which are distinctly not flat. In terms of geometry, the phosphor particles used in white LEDs are no different from the phosphor particles used in fluorescent lamps.
The same phosphor particles in white LEDs that emit the majority of the luminous flux also scatter the unconverted blue light emitted from the LED chip so that the actual emission pattern from the LED chip is irrelevant. Moreover, LED chips themselves do not emit focused beams of light.
If you shine a flashlight on a sheet of white paper (non glossy), the reflected light forms a Lambertian pattern, the same type of emission pattern from most LEDs. Sunlight reflected of a concrete sidewalk would also form a Lambertian pattern.
Our eyes are more than capable of viewing sources well above 300 nits. Direct sunlight is about 120,000 lux. A concrete sidewalk has a reflectivity of about 40%. A sidewalk in direct sunlight would be about 15,000 nits.
A 60W soft white incandescent bulb emitting 800 lumens of light would be about 22,000 nits.
I would also point out that light emitting products are regulated under 21 CFR 1040. §1040.10 covers lasers. §1040.20 covers sunlamps and UV lamps. §1040.30 covers high-intensity mercury vapor discharge lamps.
According to 21 CFR 1040, lighting products based on lasers would be illegal in the US at any reasonable light output. Europe allows laser based headlights. In the US, the output of a laser (without significant safety interlocks) is limited to 5 mW (direct laser emission, scattered light, and/or scattered light).
The issue with TV sets was not emission of radio frequencies, it was x-ray emission. Electron beams are used to generate medical x-rays. The electron beams in CRT televisions emitted small amounts of low energy x-rays. Air attenuated the x-ray energy which is why you weren’t supposed to sit close to TVs. The CRT tubes in TVs were also made of leaded glass to reduce x-ray emission.
@Eric Bretschneider – I encourage you to read the scientific research articles on flat surface Lambertian emitters, such as this one: https://www.frontiersin.org/articles/10.3389/fphy.2023.1181343/full
21 CFR 1040.40 – LED Products is entirely missing. The Soft Lights Foundation submitted a citizen petition to the FDA on June 12, 2022 to create this section, as required by 21 U.S.C. 360ii. https://www.regulations.gov/document/FDA-2022-P-1151-0001
Your reference to an 800 lumen incandescent emitting 22,000 nits, if true, does not make clear that an incandescent is a Point source, so the light disperses following an inverse square law. Measuring the 22,000 nits requires inserting a flat surface. On the other hand, an LED is already a flat surface, and in far-field, the light has a Lambertian distribution, on its own, without reflecting from a second flat surface.
The government has forced onto the public a different type of light, without informing the public that LED light is different. Basically, traditional light sources are like a basketball, while LED light sources are like a javelin, and yet the government hasn’t explained this to the public.
@Mark Baker – By definition, the intensity of a Lambertian light source is directly proportional to the cosine of the angle of light emission. It therefore necessarily follows that a Lambertian light source has a beam angle of 120 degrees. The reference you provided clearly states that it relates to beam angles of no more than 10 degrees (i.e., not Lambertian emitters).
NEMA classifies light sources according to beam angles as follows:
Very Narrow (Spot) beam angle = 10 – 18 degrees
Narrow (Spot) beam angle = 18 – 29 degrees
Medium Narrow (Spot) beam angle = 29 – 46 degrees
Medium (Flood) beam angle = 46 – 70 degrees
Medium Wide (Flood) beam angle = 70 – 100 degrees
Wide (Flood) beam angle = 100 – 130 degrees
Very Wide (Flood) beam angle > 130 degrees
Clearly, a Lambertian light source does not emit an intense beam of light as it would be classified as a wide flood. An incandescent PAR lamp would emit a beam of light that is much more focused than an LED.
I would also note that in order for ANY light source to follow an inverse square law you have to be in the far field. Formally, the far field is defined as the region of space sufficiently far from a radiating source that the inverse square law can be applied with negligible error. (https://www.ies.org/definitions/far-field/) In practice, far field is defined as 6x-10x the maximum dimension of a light emitter. The reference you provided “aims to construct a Gaussian-Schell model for the LED beam (LED-GSM) on the near-field source plane”.
Close to an incandescent filament, the intensity of light will not follow an inverse-square law.
You seem to imply LEDs never follow an inverse-square law. The area illuminated by any light source increases with the square of the distance from the light source. Any light source that did not follow an inverse square law (in the far field) would violate fundamental laws of physics – namely conservation of energy.
Lambertian light sources (reflected or direct emission) are not the hazard by themselves. Resistive stove top coils are also Lambertian emitters (https://stockarch.com/images/business-and-industry/energy/pan-red-hot-hotplate-8009) should they be banned?
Luminous emittance or luminous exitance (luminous flux per area) is at the heart of your concerns.
More specifically, the contrast in luminous emittance and the adaptive state of the eye is the problem. Car headlights during the day aren’t really an issue and few people would even notice if a streetlight was on during the day.
I would also note that even before they were banned, must incandescent bulbs where frosted to minimize glare. An incandescent filament in a clear glass bulb is hardly an eye-friendly light source. Incandescent filaments operate at luminous emittances well in excess of 10 million lm/sq meter and are on par with high power LEDs in that regard. The majority of LED light bulbs sold today include the same types of coatings (or plastic diffusers) to address glare, just like incandescent bulbs.
The government also forced halogen lamps on the public (they are more energy efficient than standard incandescent lamps) and HID lamps were a prior generation of car headlights and street lights. Xenon lamp headlights are just as bad as LEDs (in terms of CCT and intensity).
I would reiterate that I applaud your efforts to address glare and flicker, but some of your characterizations of LEDs are simply wrong. Respectfully, I believe that these errors detract from your message.
@ Eric Bretschneider
While I agree with some of your observations, I do not agree with your comment that LED car headlights during the day are not really an issue. LED headlights are dazzling even during a sunlit day, just as sunlight reflecting off a car windshield is dazzling. These things are not safe. Brighter is not necessarily better, and the blue content of these new LED headlights is extremely disturbing to me and many others I have discussed this with.
While I will agree that car headlights can be too bright, you are implying that only LED headlights are the issue. What you seem to be missing is the fact that many cars use discharge lamps for headlights. These can be equally as intense as LEDs (or even more intense) and have the same high color temperature (blue content).
Do you mean to say that high intensity discharge lamps are acceptable for headlights?
Are you just against LEDs, or against bad lighting? There is a difference.
LED technology is causing headache, migraine, seizure and other neurological illness in a class of the population. It has been seen to significantly exacerbate autoimmune disease, lupus in particular.
It is emerging as a health risk.
The French Academy for Medicine has published studies demonstrating retinopathy in children and adolescents from screens.
Very significant.