*New to Arduino* where to get started on my LED project

Hey all! I am a lighting designer and I have come upon Arduino as a possible solution for my project. I am creating a lightbox where the frequency of the light and the wavelength of the light within the box can be specifically controlled for a scientific experiment. When looking for a product to control the frequency someone pointed me toward Arduino and then I got a little overwhelmed. I don't really know where to get started.

Any and all help would be greatly appreciated.
Thanks in advance!

I am creating a lightbox where the frequency of the light and the wavelength of the light within the box can be specifically controlled for a scientific experiment.

The frequency and wavelength of light are not independent propitiates, you can't change one without the other changing.

I know of no system that will allow you to change the frequency / wavelength of light produced. The nearest I could think of is to have a bright light pass through a prism and then a motorised slot will allow a small range of light through.

I am a lighting designer

Makes me wonder if you are asking for the right thing? Have you no Physics background?

Perhaps "intensity" (brightness) and "frequency" (color) were meant. WS2812B might be a good place to start, where mixing the RGB can produce different colors, and the 8-bit PWM output of each can also control brightness.

I think we need to know more about this "scientific experiment".

Wouldn't hurt.

Hey all

So yes I mean controlling the frequency of my RGB LED tape light and setting it to a certain frequency using pwm. I realize that the two factors might affect each other which is why the wave length would have to be measured at each point.

As to the experiment it is a little out of my depth. My GF is a Neurobiologist and certain wavelengths of light trigger certain activities in fruit flies and of course how often they are exposed to the light is an important factor hence needing control of the frequency (perhaps I am not using the right language).

Whoops little bit of typo there. Yes I mean I need to control the color with RGB (therefore the wavelength) and the amount of times the LED flashes per second (the frequency). I was coming to Arduino because it seems as though a controller to set the pwm (to control the frequency) is hard to customize. The LED drivers I have found either come under 100 hundred hertz or over 1000 and I need something in the middle.

Yes I mean I need to control the color with RGB (therefore the wavelength)

No you can not control the wavelength of light with an RGB LED. You can however control the colour. Some colours can look like a specific wavelength but it is not at all the same thing. You can approximate to a wavelength by stimulating the three colour sensors found in man but it only produces the approximate sensation of the corresponding wavelength.

When you move to another species all bets are off as you can only guess what mixture of RGB produces an approximation to a wavelength to them. A lot of research is invalidated by researchers not appreciating that point.

it seems as though a controller to set the pwm (to control the frequency) is hard to customize.

It is easy to control the PWM frequency of an Arduino.
As regards programmable LEDs then the dot star is best because it has a high PWM and as long as it is above the flicker threshold it will look continuous. You can then make it flicker by turning it on and off at a slower rate. I believe that the fastest insect's flicker perception Is about six times ours. Ours is between 30 and 60 Hz.

Hey Grumpy_Mike

No you can not control the wavelength of light with an RGB LED

You can approximate to a wavelength by stimulating the three colour sensors

Sounds like you are now saying I can control the wavelength of light. Obviously I wouldn't be able to get exact wavelengths with my eye. If you notice in my first reply I said I would need to measure it at each point. I am simply going to purchase a meter that measures wave length.

I appreciate you trying to point me in the right direction of LEDs with the dot star however I am not worried about that gear. What I need help with is the Arduino side. I have no idea which one to get that is so easy to control the pwm.

Sounds like you are now saying I can control the wavelength of light.

If you think that is what I am saying then you are totally misunderstanding what I said.
You can not control the wavelength of light using an RGB LED. You can only control the intensity of each of the three different wavelength emitters the LED contains. This changes the colour pecieved by a homosapien but does not change the wavelength of light.

I am simply going to purchase a meter that measures wave length.

I would be very interested in seeing a link to something that claims to do that.

If you use a spectrometer to analyse the light from an RGB LED what you will see are three emission lines. You will not see a single wavelength.

I have no idea which one to get that is so easy to control the pwm.

They are very much the same in this respect so get a Uno.

@ShimShamMan, you will have to continue this conversation sans link to the "Lighting Navigator".

Hey Mike

This forum keeps saying I am using forbidden words... not sure what they are but I found a device that measures 380-780nm Wavelength Range. It is by a company called Lite Ing Pass port (spelling obviously wrong) the device is called the Lite Ing Nav I Gator

Also I will look into the Uno, thanks

I don't think that this measures what you think it does. It does not seem to measure a continuous spectrum to give you a wavelength reading. It appears to have multiple sensors, maybe 17 from the words to compute the colour of an LED lighting system.

As I said you can not change the wavelength of an LED. If you don't tell the experimenter this then he will wast his time, as you will be misleading him as to what you are producing.

This forum keeps saying I am using forbidden words

It looks like Coding Badly, a moderator, has determined that this web site is particularity aggressive and has banned it.

Grumpy_Mike:
It looks like Coding Badly, a moderator, has determined that this web site is particularity aggressive and has banned it.

Naw. Our toolset is not so nuanced. More of a giant slightly damaged hammer (spam is essentially a nail to be smashed from view). There is a list of verboten words. @ShimShamMan used one of those words (document used for international travel).

Thanks, that makes sense. Cheers.