Twelve Channels Of LEDs Give RRRRGGGGBBBB Light

March 12, 2019 by Brian Benchoff 31 Comments

If you’ve ever searched Mouser or Digikey for LEDs parametrically, you won’t find just one red in your LEDs. You won’t find one green. There is quite literally an entire rainbow of colors of LEDs, and this rainbow goes into infrared and ultraviolet. You can search LEDs by frequency, and an RGEB LED is right at your fingertips. The ‘E’ stands for Emerald, and it’s better than a Bayer filter.

[ayjaym] over on Instructables realized anyone could buy a dozen frequencies of high-power LEDs, and the obvious application for this is to turn it into a tunable light source. The Angstrom is twelve LEDs, all different colors, and all controlled by PWM and piped down a single optical fiber. It’s an RRRRGGGGBBBB LED, ideal for microscopy, forensics, colorimetry, and seeing octoreen.

The heart of this device are twelve 3W star LEDs, with the following wavelengths: 390, 410, 440, 460, 500, 520, 560, 580, 590, 630, 660, and 780 nm. That’s deep red to almost ultra violet, and everything inbetween. These are powered by a 5 V, 60 W power supply, and controlled via a Raspberry Pi with 12 PWM channels in a circuit that’s basically just a bunch of MOSFETs. Proper heatsinking is required.

The impressive part of this build is the optics. A 3D printed mount holds and connects optical fibers and sends them into an optical combiner that is basically just a square acrylic rod. This is output to another optical fiber that will shine on just about anything. A webpage running on a Raspberry Pi sets the PWM channels of all the LEDs, and the resulting output shows up at the end of an optical fiber. It’s great if you want to look at something in a specific frequency of light. It also looks really cool, so that’s a bonus.

RGB Word Clock Doesn’t Skimp On The Features

March 9, 2019 by Tom Nardi 5 Comments

Like most pieces of technology, word clocks seem to be getting better and better every year. As hackers get their hands on better microcontrollers and more capable LED controllers, these builds not only look more polished, but get improved features and functions. Luckily for us, the rise of these advanced modular components means they’re getting easier to build too. For an example of these parallel traits, look no further than VERBIS by [Andrei Erdei].

This colorful word clock is powered by an ESP8266, a 8×8 RGB LED matrix, and a WS2812 RGB LED controller module. [Andrei] used the diminutive ESP-01 which can plug right into the LED controller, and just needs a 3.3 VDC regulator board to complete the very compact electronics package.

To keep the LEDs from interfering with each other, [Andrei] has designed a 3D printed grid which fits over the matrix board. On top of that goes a piece of paper that has the letters printed on it. He mentions that he was able to get good results printing this “stencil” out on an inkjet printer by simply running the same piece of paper through a few times; picking up more black ink each time it went through. Judging by the sharp characters seen in the video after the break, the trick worked well.

With his hardware put together, [Andrei] turned his attention to the software. We really think the project shines here, as his clock not only supports NTP for automatically setting the time over the Internet, but offers a full web interface to control various functions such as the LED colors. You can even change the NTP server and network configuration right from the UI, which is a nice touch compared to just hard coding the values into the code. Even if you don’t use the same hardware, the open source control software is definitely something you should look into if you’re building your own word clock.

We recently covered another easy to build word clock that used an LED matrix and not a whole lot else, but it was quite tiny. This build is a much more reasonable size for a desk, but you’ll probably need to break out the laser cutter if you want to get much bigger.

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Tech Imitates Life: Fireflies Make Better Light Bulbs

March 5, 2019 by Al Williams 46 Comments

While we often think we are clever designers, living things often meet or beat the best human designs. It is easy to forget that nature even has living lightbulbs, among them the firefly. Researchers from Penn State decided to compare how fireflies create light and found that they deal with a problem similar to LEDs. The insight may lead to an increase in efficiency for LEDs, which is currently about 50%.

The problem is that some light generated never gets out of the LED (or the firefly’s body). Some light inevitably reflects back into the device. One known mitigation for this is creating a tiny texture pattern on the LED surface which allows more light to escape. These are typically a V-shaped structure etched into the surface. This isn’t news to the firefly, however, which has similar structures on their lanterns as do some other light-generating animals (apparently glowing cockroaches are a thing). However, the organic structures differ from LED textures in an important way.

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WiFi Makes The Heart Glow Fonder

March 2, 2019 by Lewin Day 2 Comments

It’s more than a little too late for Valentine’s Day this year, but if you start now, you’re sure to be looking good next February. Print something that truly conveys how you feel, through the magic of wireless communication and RGB LEDs (Youtube, French).

Yes, [Heliox] has built a Valentine’s day project, and the presentation is top notch as always. A heart is 3D printed in white filament, with two chambers separated by a thick wall. Each chamber features five NeoPixel LEDs, controlled by an ESP8266 in the base. The color of each chamber can be controlled through the Blynk smartphone app, allowing you to choose the exact colors that best represent your relationship.

The 3D printed heart does a good job of diffusing the LEDs, with the device showing a rich and consistent glow without any unattractive hotspots. It’s a fun holiday build, and if you’re quick, you might just have time to print one yourself if you start right away.

[Heliox] has good form when it comes to LED projects – her infinity cube is particularly impressive. Video after the break.

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Teardown Of A Luxury Bluetooth Nightlight

February 28, 2019 by Tom Nardi 4 Comments

If you had asked us yesterday what peak nightlight technology looked like, we might have said one of those LED panels that you stick in the outlet. At least it beats one of those little wimpy light bulbs behind the seashell, anyway. But after looking at a detailed teardown of the “Glow Light” from Casper, we’ve learned a lot about the modern nightlight. Such as the fact that there are adults who not only sleep with nightlights, but are willing to pay $89 USD for one.

But more importantly, as [Tyler Mincey] demonstrates in his excellent look inside one of these high-end nightlights, they are gorgeous pieces of engineering. Even if a nightlight next to the bed has long since gone the way of pajamas with feet on them for you personally, we think you’ll be impressed just how much technology has gone into these softly glowing gadgets.

On the outside they might look like marshmallows, but the insides look far more like what you’d expect from an expensive piece of consumer gear. It’s based on the Nordic nRF52832 Bluetooth SoC which is becoming an increasingly common sight in consumer gadgets, and uses an inertial measurement unit (IMU) to detect when it’s moved or twisted and adjusts the light output accordingly. If you’ve got the disposable income for two of these things, they’ll even synchronize so that twisting one will dim its counterpart.

The teardown that [Tyler] did on the Glow Light is quite frankly one of the best we’ve ever seen, and while it might be a bit light on the gritty technical details, it more than makes up for that with the fantastic pictures that are about as close to actual hardware porn as you can get. The only question we have now is, how long until a hacker replicates this design with a 3D printed enclosure and an ESP?

[Thanks to Adrian for the tip.]

Zach Archer: Live Coding 500 Watts For ToorCamp

February 28, 2019 by Brian Benchoff 2 Comments

ToorCamp is a five-day open air tech camping event held every two years somewhere around the northwest corner of Washington state. Think of it as something like Burning Man, except you can survive for three hours without water, there aren’t a whole bunch of scenesters and Instagram celebs flying in on private planes, and everyone there can actually build something. Oh, and ToorCamp has delivery drones that will send you creme brulee. These mini creme brulees were probably made with the hot air gun hanging off a soldering station. Don’t worry, you’re getting fresh air that’ll balance out the heavy metal poisoning.

For last year’s ToorCamp, the biggest welcome sign was a 40-foot-long illuminated ToorCamp sign. This was designed, built and coded by Zach Archer, and he was at the 2018 Hackaday Superconference to give us the details on how he made it and how it was coded.

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Teardown: AppLights Personalized Projection

February 27, 2019 by Tom Nardi 22 Comments

Listen, it hurts to hear, but somebody needs to say it. It’s over, OK? You’ve got to admit it and move on. Sure, you could get away with it for a week or two in January, but now it’s just getting weird. No matter how hard you fight it, the facts are the facts: the holidays are over. It’s time to pack up all those lights and decorations before the neighbors really start talking.

But don’t worry, because there’s an upside. Retailers are now gearing up for their next big selling season, which means right now clearance racks the world over are likely to be playing home to holiday lights and decor. That wouldn’t have been very interesting to the average hacker or maker a few years ago, after all, there’s only so much you can do with a string of twinkle lights. But today, holiday decorations are dripping with the sort of high-tech features you’d expect from gadgets that are actively aiming to be obsolete within the next ten months or so.

Case in point, the “AppLights Personalized Projection” which I found sulking around the clearance section of the Home Depot a couple weeks back. This device advertises the ability to project multi-color custom messages and animations on your wall, and is configured over Bluetooth with a companion application on your Android or iOS device. At a minimum we can assume the device must contain a fairly powerful RGB LED, an LCD to shine the light through, and some sort of Bluetooth-compatible microcontroller. For $20 USD, I thought it was worth taking a shot on.

Around this time last year, the regular Hackaday reader may recall I did a teardown for a Christmas laser projector. Inside we found red, green, and blue lasers of considerable power, as well as all the optics and support hardware to get them running. It was a veritable laser playground for $14. Let’s see if the AppLights projector turns out to be a similar electronic cornucopia, and whether or not we’ve got a new Hackaday Holiday tradition on our hands.

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