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Me as well.

FastLED was the main reason I was able to complete a holiday window display for a prominent NYC retailer, with a very limited budget, and only 2.5 weeks to do the project. I really pushed the library to the limits, as we had more LEDs and effects than most Arduinos could handle with a smooth frame rate, so we ended up using an Arduino Due clone and driving the LEDs through almost all the serial lines. FastLED handled it all, no problem.

Thank you, Dan, for your gift.

Rear fog lights: something more cars should have in the US for this exact situation.

My understanding is that it's still up for debate how linear or nonlinear melanopic sensitivity is, which is the main thing we are attempting to show in the plot.

Their non-dimmable filament bulbs (silver base) tend to be pretty low flicker, but I found the dimmable ones (gold base) have upwards of 30% flicker, even at full output. Without having done a teardown, I suspect the flicker is due to the power electronics.

The main purpose of this graph is to compare "melanopic" light, which is light in the blue-green area between about 400 and 580 nm (the gray curve). This is the sleep-disturbing blue light everyone is talking about, which also includes green, as you remarked. The vertical scale is just relative power from 0-1, for the relative amount of light at each wavelength, as you said.

Why not normalize? Because those other sources are twice as bright. We're trying to compare to a light source people would typically buy. Yes, you could use a ~40 watt incandescent at about the same lumen output, but it would still have a higher melanopic effect. The melanopic ratio for incandescent is usually around 0.50-0.54, which ours is 0.39. You'll also notice that we did not include a daylight LED in our comparison, which is something our competitors do, but we think it's just a ridiculous exaggeration of the effect.

In other words, if you pointed a spectrophotometer at the 4 light sources at a consistent distance and did not normalize, that is roughly the plot you would get.

If we take reading as a use case, there are aspects of our design which enable you to use a source that is half as bright and still read just as well. For one, the CRI and R9 (red color rendering) are very high, basically at incandescent levels. This makes the printed page look better. The beam angle is much wider than a normal LED (most LED bulbs mounted upright will shoot all the light at the ceiling, not where it's needed). And most people simply don't need a 60 Watt bulb (650-800 lumens) to read with, even if they don't yet realize it.

Why not eliminate all blue and green? It's certainly possible, and there are bulbs that do that. The problem is that blue/green-free light is very orange/yellow, and in our testing, most people found the light undesirable and impractical. Our theory is that people would go back to their old higher-blue lighting after some time. In other words, people like white light. However, we are working on a mostly melanopic-depleted source with a slightly different use case.

The point is that it comes down to both spectrum and illuminance (brightness). Everyone else in the market is only considering spectrum. There is an explicit tradeoff between color rendering (CRI, R9, Rf, Rg) and the amount of blue/green reduced. If you can balance those two, and then give someone between 100-200 lux, as opposed to 300+ lux for typical reading light, the melanopic input is much lower and the light is more comfortable to use for most people. Our light will give you about 100-200 lux in a shaded or unshaded lamp at a typical reading distance. But it's hard to explain that from a marketing perspective.

Related: Signify (formerly Philips Lighting) recently lost a judgment by the U.S. International Trade Commission on their patent licensing program [0]. Lighting companies that have fought patent infringement claims against Philips/Signify and similar entities have often won but at a high cost [1]. Many others are intimidated into licensing, or they go out of business.

My understanding is that lot of it boils down to the patents being relatively vague or overly broad coupled with overly aggressive enforcement.

[0] (NOTE: PDF) Signify Loses at the U.S. International Trade Commission in Setback to its LED Patent Enforcement Campaign https://edisonreport.com/wp-content/uploads/2019/07/ITCSigni...

[1] Great analysis of the toll Philips' licensing program has on the industry by WAC Lighting, which has fought infringement claims: W.A.C. Issues Strong Response to Philips ITC Complaint https://www.linkedin.com/pulse/wac-issues-strong-response-ph...

Adding capacitance to a "linear" driver design is one way to reduce modulation, with some tradeoffs. There are other power supply designs, such as switch-mode and several variations of "constant current" drivers, which could reduce modulation at a higher cost. Adjusting the frequency also plays a role in mitigating perceived flicker.

In higher-end drivers, you'll often see a hybrid approach, such as constant current between 5 and 100% and PWM below 5%. Drivers with deep dimming down to 0.1% are just using 10-bit PWM. This would be difficult to do in a bulb form factor.

I haven't seen any meaningful research into the persistence of various phosphors. It's an interesting thought. My guess is that there could be some effect, but usually we would just try to improve the power electronics.

Not all filament designs have horrendous flicker—we are selling one that we designed with 8% worst case, usually more like 2-3% [0][1]. That's better than incandescent.

Even the normal non-filament LED bulbs can have high levels of flicker. I found one product claiming to be "healthy" that had around 55% flicker.

Most of the bulbs in The Home Depot are going to flicker a lot, especially the filament LEDs.

[0] Bedtime Bulb: Low-blue, low-flicker light bulb https://bedtimebulb.com/

[1] When I say percent flicker, I am referring to the modulation percentage. A good primer is this article: https://www.dial.de/en/blog/article/ieee-1789-a-new-standard...

There are still BP-branded stations in the Philadelphia area, to the best of my knowledge. Maybe elsewhere too.

BP has gas/petrol stations, so close enough?

I see oarsinsync posted this comment:

>The downside is every single thing you do is logged and tracked against your card, and associating a card with an individual is just one MTR ride with facial recognition away.

Possible, although facial recognition seems to be used much less widely in HK than the mainland.

Perhaps police checkpoints are another concern: you might get stopped entering or leaving the MTR if your Octopus card shows you were at one of the stations where the protests took pkace. Although, isn't it easy enough to get off at Central (where the protests were not taking place) and walk over to Admiralty/Wan Chai (where they were), only 1-2 stops away?

Personally, I'd be more worried about discussing the protests via SMS or WeChat than getting there on my Octopus Card. Disclaimer: not a HK citizen.

As a frequent visitor to HK and Octopus Card holder, I don't believe I ever had to present ID to obtain my card. I just purchased it with cash at the Airport Express counter. Is it different for HK citizens?

I've been using Fi for 3 years. CS has always been hit-or-miss in my experience, but it has gotten worse now that there are a lot more subscribers (thanks to iPhone support and the massive Pixel 3 promo they did last year). They tend to send a lot more generic non-answers, never call back during your call back period (or call at some random hour like 4:30 AM), or just don't even respond at all anymore.

Like many companies, if you keep calling you'll eventually get someone awesome who can pull strings. But it's frustrating.

I've had the experience twice of phones getting lost on the way to me. They would insist on running an "investigation" that could last weeks or never resolve, before they would send a new device. In both cases, I had to be pretty pushy with the agent that the phone either fell off the truck or someone at FedEx stole it. Usually I needed a new phone ASAP due to a failure.

Don't get me wrong, Fi is awesome, especially for international travel. Just show up at the airport and you've got service. The data rate structure is totally fair for how I use it. But there are definitely benefits to having a local Apple Store or Best Buy with a compatible phone in stock.

Can confirm. At first, I thought it was only calls to Canada from the U.S. Now I am only able to get through intermittently, Canada or not.

If it's the company bus, does that mean you are on company property?

Disclosure: I design and sell lighting products.

The LED component probably will last 60 years (8 hours a day). My guess is they are using Nichia LEDs, which tend to have an L70 (lifetime at which the brightness stays above 70% of the original output) of 150,000 to 300,000 hours. If you run them cool enough and at the right current/voltage, the LED itself will actually last that long.

However, the LED is probably the most reliable part of the whole lamp. You might see a few units last that long, but most of the other electronics will have failed by then. And even if they have not failed, both the LEDs and controls will be seriously out of date by then.

If you look at the market Dyson is in (very high-end lighting), $600 to $900 is in the same order of magnitude on price. Brands like Artemide, Marset, Flos, Roll & Hill, and Anglepoise all command prices most people would think are ridiculous. With Dyson, you get a lot more functionality than those other brands, but I would consider this purchase more like a luxury car (service life of maybe 20 years, original owner has it for 3-10 years) than a high-end watch (could last many decades with consistent service).

I've seen the previous task lamp from Dyson in person, and it does use a lot of metal (minimal ABS). But that doesn't change the argument around electronics. I feel like Dyson really didn't have to make the ridiculous 60 year claim. Enough people in the target market would still buy it.

Can confirm. Also, API integrations, such as Buffer, are not working.

> empowerement that means more responsibility and no leverage

Wow, that so succinctly summarizes how I've felt at more than one workplace

You're referring to 3-way, I think. I think most people would classify that as a dimmer.

It did, and it actually does have a circadian effect. But it has much less illuminance than most artificial light sources. That's what I mean when I say "little nighttime light."

It will be in a few months. Shoot us an email and we'll make sure you're aware of the launch:

hey AT bedtimebulb DOT com

Thanks!

I'm not a doctor, but we know about the negative effects of light on sleep. Our species evolved with little nighttime light, and we know the mechanism by which our circadian rhythms are tricked by artificial light.

Most sleep experts (including pediatric sleep experts) recommend blacking out your room, removing all electronics, etc.

Perhaps an expert in this area can chime in, but I don't think light during sleep is positive.

We never published it (just internal market research), but that result was based on about 500 responses. We controlled for the typical demographics.

It's not really a night light. More like a before-bed and wake-up light.

While they don't publish the brightness, I asked Casper support, and they said it is about 375 lumens, which seems right anecdotally (I don't have an integrating sphere to verify). Note that you need to open the app and set "Overall Brightness" to max (just one time, not every time) to get that many lumens, otherwise, it's more like 300.

That's roughly equivalent to a 40 Watt light bulb. 100-150 lux at a usable distance (which is what this would give you) is a good setting for most people (from what I've seen). For my eyes (age 26) that's plenty to read with.

Yep, check out a few of the studies referenced at the bottom of f.luxometer: https://fluxometer.com/rainbow/

I totally agree the dim to dark is an amazing feature before bed. I just wish they would use something better than a 2700K LED if it's supposed to be used in the 15-45 minutes before sleep.

In my opinion, if people are able to sleep in darkness, they should, and it's not a good habit to start kids out sleeping with the lights on.

That's odd—I haven't left it on long enough to notice. So they really intended this light to be used for short time intervals.

Thanks for the clarification, Michael!

We did a lot of research on this, and fewer than 5% of people studied (Americans of various socioeconomic status) had dimmers in their bedrooms.

One thing to point out is that the circadian rhythm is (largely) not directly influenced by the cones or rods (to our current knowledge). It is a third set of photoreceptors, the ipRGCs, which detect blue/green light and provide input to the circadian rhythm in the pineal gland/suprachiasmatic nucleus. The gray area is the sensitivity of the ipRGCs.

Also, that's a good point about the colors vs. dotted/dashed lines. I'll look into that, thanks!