I’d like to buy a Mudita Harmony, and the next gen of Mudita Phone. I’m concerned about the amount of artificial blue light in their front lights, as I am extremely sensitive to short wavelength blue light, and overexposure causes further vision loss for me.
I understand both the Pure and Harmony have 2700k front lights. Is that made with a blue or UV diode coated in phosphor? Is it made from a narrow-band diode? Do you have a graph of the emission spectrum available? Any chance you could use a narrow-band diode in about 690 nm for the new phone?
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Thank you for taking the time to write to us.
The concept of “color temperature” and “narrow-band emission” describe two different characteristics of light sources and are often used in different contexts.
We’ve passed on your concerns to our team and are waiting for them to respond.
However, it’s important to know that while a narrow-band diode emitting at about 690 nm could be used in an alarm clock, it might not be the most versatile or cost-effective option for general use.
A narrow-band diode at 690 nm would be particularly useful in applications where you want a very specific red light, such as in medical equipment, spectroscopy, or optical communications.
Let’s wait for our team to respond with a concrete answer if this is something we can consider.
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Thanks so much for checking on that.
I realized I made a typo in my original post. I believe I meant to say 588-590ish nm. That would emulate the emission spectrum of the low pressure sodium lamps that used to be on our streets. It’s a spectrum that’s very gentle on the night vision. Bonus, mosquitoes tend to fly away from 530-590 nm light, according to some marketing material for yellow LED lights and some studies I found while trying to understand my light sensitivity. I tried to include a link for a low pressure sodium lamp in my post, but I guess the forum robot won’t let me. If you do an image search for “low pressure sodium lamp spectrum”, you’ll see what I’m writing about.
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Thank you for the clarification. I did some research on low-pressure sodium lamps and it looks like they are used in some astronomical observatories because their narrow spectrum allows astronomers to easily filter out the “light pollution” from these lamps, making it easier to observe celestial objects. Like you said, they are also used in some street lighting applications where color rendering is not a primary concern, as they are quite efficient in terms of the amount of visible light produced per watt of electrical power consumed. However, their poor color rendering makes them less suitable for general-purpose lighting.
After talking to our team about your previous questions & they told me that this is not an option for future phones. However, they’re taking this under consideration for other devices.
Additionally, in response to your question about a graph of the emission spectrum available, our team has informed me that we actually ordered equipment to measure the light spectrum, so in the near future we will be able to make such measurements.
Hopefully this clears things up for you. Let us know if you have any other questions.
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@urszula, thanks for looking into it. Can the light on the phone be just completely turned off?
What products is the team considering using 590-ish nm lighting in?
I’m looking forward to the graphs of light emissions. I find that information very itneresting and helpful.
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Any word on that graph of light spectrum emissions?
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@dandelionc I’ve reached out to our team & waiting for a reply.
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Thanks, I’m looking forward to the reply.
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Hey @urszula, in addition to a light spectrum graph for the next phone, what devices are the developers considering a spectrum the emulates low pressure sodium?
I’d like to see that so much that I’d consider buying almost anything that incorporated the low sodium spectrum.
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This is the Mudita Harmony measurement. We use warm white light rather than 690nm orange light because it is more natural and friendly to the eye.
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Thank you very much, @urszula, for giving me this information.
Is it the same spectrum as the Mudita Pure phone?
The light on the phone hurts my eyes. I’m grateful it can be turned off.
Something that may interest your team:
There’s a dopamine center in the brain that is only activated by 480 nm.
Notice the absence of that in the spectrum?
Another thing that may interest you/team, blue light stimulates wakefulness, and there’s some evidence that occurs down to the green part of the spectrum.
A company named Hooga sells reading lights in the red spectrum that are meant to not wake up other people in the room.
A person who wakes up in the middle of the night and checks their Harmony may accidentally stimulate wakefulness in themselves, and make it more difficult to fall back asleep if they are prone to insomnia.
The easiest to digest explanation of all of this that I’ve found can be listend to here: https://open.spotify.com/episode/1Car0yZ7lpslqnbcX4oSNs
To produce dopamine, an electroluminescent light would be desirable, since the peak emission of electroluminecence is about 480 nm.
To avoid unwanted wakefulness and sleep disturbances, any nm amber or red LED will outperform.
Thank you again for getting me that graph.
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… and Kompakt! It would be great if quality was preserved over all e-ink products. And should be advertised for all people that do need it.
I myself have serious eye condition (operated ablatio retinae) and larger fonts, stronger contrasts and more background light do help greatly.
Such “accessibility features” can also be advertised and create niche and small, but devoted user base too.
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@urszula: I found this while reading the book Good Energy by Casey Means, M.D.:
How does the environment we live in today ravage our mitochondria? The answer comes down to ten main factors…:
…
9. Artificial Light and Circadian Disruption: With the advent of portable digital devices, we are being exposed to constant sources of artificial blue light, which is now considered to be both a direct and indirect contributor to mitochondrial dysfunction. Exposure to intense light at unnatural times affects our circadian rhythms and the many metabolic pathways that are meant to be activated in specific daily cycles that are dictated by when our eyes (and therefore our brains) are exposed to light. Compounding this, we now spend little time outdoors, depriving ourselves of viewing direct sunlight early in the morning, which is one of the best signals we can give our brains to reinforce our natural circadian rhythms.
…
Another great reason to order the Mudita Kompakt!
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I too am very interested in 480nm and similar parts of the light spectrum that support health and do not block melatonin. And so do users on the Harmony 2 - blue light detected thread.
It makes sense that Mudita needs to consider what will work for the largest group of likely users, so I wonder about Mudita selling an optional maybe stick on clear disk for Bell and Harmony for those who want a blue light-free alarm clock. Maybe the same is possible for Kompakt.
Two possibilities are a thin, appropriately coloured film with an easily liftable adhesive, or a clip on disk.
Maybe someone knows places to buy suiltably coloured material, which holds its shape and smoothness, that people could place over blue light emitting screens themselves?
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I’d rather have different color light spectrums available than different colored phone casings. I have not found a “white” or even “warm white” LED that my eyes can tolorate in dim or dark conditions. If LEDs are going to be used, I need them to be red, or a truly zero blue light emitting amber.
I asked on the Quill OS forum, and because e-ink can be thin enough to allow light to pass, an electroluminescent panel would also suffice. Without a filter, electroluminescense has a light spectrum peak of cyan/green, about 480-500 nm. This doens’t seem to hurt me like the 400-455 peak of “white/warm white” LEDs.
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Didn’t think of that… An option to have a built-in bluelight filter film within the screen would be great. Perhaps we can at least get such thing like bluelight on-screen glass? There are such things on the market, it’s a matter of a proper form-factor.
Edit: I just found Ocushield for most popular phone brands but I believe there might be more. What puzzles me, the said screen protector doesn’t “orange-ize” a display.
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@buiosu It does seem Ocushield has a decent reputation, along with Fiara. I found this article helpful in thinking about options: 10 ways to counteract harmful blue light from screens • Clear Space Living Its author tends towards thorough research - no-one covers every detail though! On reading their websites, these two companies’ screens block 54% and 46% of harmful blue light wavelengths, respectively. This may explain why in an earlier version of the linked article Karen described using two layers of the screens together - a double dose of blue blocking.
I’d like to know: what percentage blocking of these wavelengths is enough?
I am curious if the films @jordan suggested: Colored Overlay Clings For Computers, Tablets, & Phones - Irlen Institute are effective for blocking blue light, and how effective. @jordan have you ever used your light spectrum meter to measure before and after putting a film on a screen? It seems to me their golden rod colour is likely the most workable for an amber colour. They have yellow, but it may be too close to green, and their apricot doesn’t look solid enough colour wise to do the job. Their red may work, but will be darker. I am comparing the films to what I’ve seen of available blue light blocking glasses. Some testing showed amber coloured glasses block 85% of blue light. in the 380 - 500 nm wavelength range, and red 99%. While that removes the 480 nm wavelength mentioned by @dandelionc as being good for dopamine production, maybe it could work for Mudita’s clocks. Users don’t usually look long at clocks so removing the problem wavelengths sufficiently is the key challenge.
Does still leave questions about what percentage blue light blocking is enough.
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While I do very much appreciate the suggestion, the reasons why I won’t just get a cling are:
The clear ones I try that claim less than 60% reduction don’t cut blue light enough to give me comfort when I tried them…
Colored clings will reduce contrast in conditions where a backlight isn’t needed. This is a stand alone reason to make clings unappealing to me.
No data on the actual nanometers of light blocked by Irlen clings are available, that I can see. Also I don’t see if they’re matte or glossy (glare is another huge visual issue for me, I avoid glossy things.)
On non-e-ink Android devices, the app Twilight does a good job, on Linux, night color.
If I’m going to spend hundreds on a new device, it needs to do what I want, how I want, or it’s just not worth it to me because of how large a part of my income that is.
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Yes, devices have to justify themselves in my life too - the details really matter. I can’t afford to buy things that, for me, don’t work.
Mudita Pure caught my attention due to very low radiation and e-ink screen, but I never bought one because push button texting would be too time and energy consuming in my situation.
Yes, reduced screen contrast really matters for phone use. Using Iris and before that f.lux on my computer to block blue light markedly reduced contrast, making reading the screen much harder. The Irlen Institute cling film idea from @jordan seems most workable for Mudita’s clocks. I don’t spend long looking at any clock, so if I can stop melatonin interference by a permanent film, I’m likely to try it. I bought the clock for a far gentler alarm than I’ve ever had, and can use external lighting to see it. I’m expanding external lighting options, looking at Hoogalight and BlockBlueLight’s options. Also curious about the RedgrassCreative.com R9 desk lamp which won a Red Dot award, and like Mudita, was funded through KickStarter. It says it is flicker free, glare free, full spectrum with harmful blue light omitted.
Would be interesting to see the results on a light spectrum meter with Irlen cling films (and amber and red lights on the market and the R9 desk lamp). Thanks to @jordan I’ve been reading the Irlen Institute website. They offer 14 different colours of cling films and 75 colours in non-cling films. The non-cling films have a matte side and a gloss side. Irlen has a whole knowledge base about glare and visual processing that has been around decades but is not widely known. I’m finding it fascinating.
Given you mentioned using Twighlight, have you found an android phone that is ok for you?
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The fact that it does not turn the display orange or red proves it doesn’t block enough blue light to fix the circadian disrupting issue.
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