Led light material

I want to program a led light behind two glasses (similar to the render of https://www.ledkia.com/fr/acheter-plafonniers-led-basic/519-plafonnier-led-rond-24w.html?gclid=CjwKCAiA_9r_BRBZEiwAHZ_v10W12beeNOLXaOhm5Zc1mHEofm5ezZayFXmhw1Pf-oauxiKeRptTIxoC84kQAvD_BwE&gclsrc=aw.ds)

I made a glass render, but I am stucked for the way to implement the lighting

Not sure I understand where you are stuck. Is your link correct, I don’t see any glass in there?

If you are trying to recreate that fixture, you are probably not approaching the thing the right way. It would be too expensive to consider creating the lights behind the plastic diffuser, and let them be scattered by the material. Make the diffuser emissive itself.
And if you still consider placing a light behind a glass plane, make sure to turn off the shadows on that glass object (Object panel > Visibility > Shadows).

In want to model an existing cell lighting :


in reality this is a glass with led backlight

In my blender view, I setted up glass material, but this may not what should be required

Regarding shadows, i am not sure, because I must be able to sea chinese shadows in the camera when an object is in front of the lighting wall.

my html weblink was pointing to classic led lighting lamp, since finally that s a similar effect !

I guess you could do this with the principled shader: Set it to a low roughness to get the reflections and use the emission parameter to create the glow.
I also found that turning up the metal parameter helps to pronounce the reflection, so that might help you create the look you’re going for - though there are probably way more realistic approaches to this.

You can also use the shader nodes to create the darkening on the edges. Here is a simple setup that isn’t adjusting for the scale of the panels, but it still kinda does the trick. The light panels are all planes with the same material:

Hope this gives you some ideas. :slight_smile:

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I did some testing on this a few years back and found that if you are wanting to simulate light behind a translucent diffuse material, it was really better to make the diffuser itself emit light, rather than trying to emit light from behind it.

Take a look at these two images. The first image uses a point lightsource inside the box - with a diffuser made from a squashed cube with a white translucent shader applied.

The second image - the light was removed and the shader on the diffuser was changed to be a white emission shader instead.

Softbox1

Softbox2

There is very little to tell them apart. There is a slight falloff towards the edges of the translucent shaded diffuser, whereas the emission one is completely uniform. This falloff could be easily simulated using a radial gradient however.

The biggest difference between them is performance. To get a comparable level of noise between the two images - the one with the translucent diffuser took 4x as many samples to render (600 vs 150) - so there is a massive performance gain to be had going down the emission shader route.

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Many thanks, I will explore these solutions