Yuji recently sent me their new Serenity sleep lamp to review and boy! If you’re looking for a high-quality circadian sleep lamp, check this out!

serenity lamp on pink white mode on nightstand

The Serenity Night Lamp

While its price point will put off some, the Serenity lamp is built for the circadian rhythm enthusiast who values very high-quality light.

The Serenity is a wireless, portable 3-in-1 night light capable of putting out very high CRI nature light with no invisible flicker!

There are three color modes to choose from:

yuji serenity on moonwhite mode
yuji serenity on warmpink mode
yuji serenity on flamewarm mode

Using the Serenity is simple. One touch to turn it on, two to turn it off, and to dim the light you just long-press the top.

The Serenity also saves the dimming level of each setting so when you cycle back it will remain at the previous level, which I think is a nice touch.

It can be charged with a USB-C cable, thank heavens.

shot of charging port on serenity lamp

Weighing in at 1lb 4oz, its thick glass shell feels heavy in the hand, which helps to make it feel like the premium product it is.

So what about our usual testing, does this lamp live up to its hype?

Testing the Yuji Serenity Lamp

We placed the Serenity lamp in our homemade integration sphere to get a high-quality reading of its light with our lab-grade spectrometer.

serenity lamp being tested

Color Modes

Let’s go over what you’ll get from each mode:


Moon-white is perfect for late-night color-sensitive work, maybe you like to do art to wind down or you just really appreciate a well-tuned warm colored LED.

yuji serenity lamp on moonlight mode

I measured the Moonlight setting at around 2900K which is just under the advertised 3000K.

This is the high CRI mode as well, which sits at around 95.7 when including all 15 colors, with an R9 of 97.5 which is quite impressive.

yuji serenity sleep lamp 3000k setting spectral power distribution graph
Moon-white spectrum

As you can see the spectrum in this mode is fantastic, with a near-perfect slope upwards unlike most LEDs. Yuji has done a fantastic job with this phosphor!


This mode provides just a hair of full spectrum light still, with a very reduced blue and green output, so you’ll still get some color reflected from the objects around you.

yuji serenity lamp on pinkwhite mode

I measured the Moonlight setting at around 1900K which is once again just under the advertised 2000K.

yuji serenity sleep lamp 2000k setting spectral power distribution graph
Pink-white spectrum

Just enough of the full spectrum left for discerning different colors but much less if you’re concerned about the moon-white causing too much potential melatonin suppression.


This is the mode we use the most by far. The color is hard to capture, but it’s almost like rose gold jewelry in light form.

yuji serenity lamp on flamewarm mode

It’s extremely pleasant and has become our primary light source at night while we wind down for bed.

yuji serenity sleep lamp flamewarm setting spectral power distribution graph
FlameWarm™ spectrum

There is a tiny amount of blue light still being emitted in this mode. however, it is quite minuscule and does help to give its radiant rose gold glow.

I’m not personally too concerned with it as I’m not a purist when it comes to blue light, I know myself well, and when I move it closer for occasional reading or lighting myself for a video call past 8, I just dim it a little bit.


One of the other guarantees with Yuji’s products is they take a considerable amount of care when it comes to invisible flicker, and none of their products, including their full spectrum light bulbs, have low-frequency flicker.

yuji serenity lamp flicker risk graph
Flicker risk graph
yuji serenity lamp flicker waveform graph
Flicker waveform graph

While there is some flicker at a depth of around 5%, it also flickers at around 30kHz or 30,000 times per second, which means it poses no risk to the human eye.

This means unlike many LKED products out there, this one won’t visibly flicker in slow-motion videography for example.


Conclusion and Final Thoughts

I like it! I’m glad I have one.

The color quality is superb and since it’s portable you can easily place it below eye level which is ideal from a circadian perspective.

It also kinda doubles as a conversation piece on a coffee table, as basically everyone who sees it thinks it’s super cool haha

serenity lamp on pink white mode on coffee table

If you’re a Huberman fan or you just like to optimize your lighting environment, I can’t recommend this enough! The only real downside is the price, but if that’s no object to you it’s a great product.

This would also be excellent for traveling so you can always have a dependable circadian-optimized light source for use in hotels.

Yuji Serenity Circadian Night Lamp

yuji serenity sleep lamp


  • Truly full spectrum high CRI light
  • Flicker-free light source
  • Wireless operation is perfect for travel
  • FlameWarm mode is beautiful!


  • Relatively expensive
  • Tiny amount of blue light left on the warmest setting

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