How to combine the light of several LEDs into one diffused general light?

Question

Do it yourself

Good afternoon, dear habrausers.
I understand that the portal is still primarily for the IT community, but I periodically saw here people who understand physics and possibly even optics.
I have a possibly very stupid question, but this is not my profile at all and I can not solve it myself yet.
Let's say for my homemade flashlight I use several
monochromatic multi-colored LEDs, let 's say such , but multi-colored. If we put a diffuser to these LEDs, let's say this , then the resulting light from the LEDs still turns out to be uneven, that is, it will be seen that one part of the diffuser predominantly glows with the color of one LED, the other of the other, and so on ...
It is necessary that all three light sources mix and give one common diffused light at the output. so that it looks like light from an incandescent lamp, for example, so that it is not clear that there are three point light sources.
I understand that some kind of lenses or prisms are needed. But I still do not understand what and where they can be bought. Somehow I tried the Fresnel lens on simple cylindrical LEDs, I also failed to achieve uniform dispersion.
I hope that in these hubs there are people who are knowledgeable in optics, physicists or photographers, I will be grateful for any practical advice. I do everything for the sake of science :)

Answer 1

How to combine the light of several LEDs into one diffused general light?

Maybe a file? Literally

Answer 2

If the diffuser is matte, you can send three spots of color to one area so that they overlap. Direct with lenses or, in the simplest case, orient the LEDs (they have a built-in lens).

Answer 3

IMHO you are digging in the wrong direction. It is much easier to replace all single-color LEDs with rgb and put the most common reflector.

Answer 4

so that there are no light spots, the light from the diode to the diffuser must be delivered using a simple collimator. Light guides can also act as a collimator, but their design and manufacture is probably not for home conditions.
Once I dismantled a 4-color indicator lamp of Soviet times - color mixing took place due to collimators directing radiation onto a frosted glass.

Answer 5

There are RGB diodes of different power, there are also RGBW diodes, there are lenses for them with different lighting angles and surfaces, in this case it makes sense to look at matte and honeycomb ones.
A similar technique is often used to illuminate aquariums.