From reading i’ve gathered that regular glass seems to transmit about 80-90% of the light going through and coated lenses seem to hit 95% or more, so i am wondering what range in percent of light is reflected by white house paint, the stuff used for walls and ceilings. Does gloss or matte make a big difference?
Also for other colours would be interesting information
From what i can gather Matte reflects more in all directions, ( while gloss reflects more only at a 180 degree angle back to the light source)
I was looking for an answer to a similar question:
http://engineering.mit.edu/live/news/1914-why-doesnt-a-plain-white-piece-of-paper-reflect
thanks for posting that, its a well written explanation of something i’ve often wondered
i’m sure my question has been asked before, but i thought i’d be lazy and ask here instead of testing my google-fu
That is not how reflections work, angle of incidence = angle of reflection.
Mirrors absorb some of the light but do not essentially change the energy levels of the photons.
And as said above, angle of incidence = angle of reflection.
White objects, like paper, absorb photons which excites electrons in atoms and molecules of the object according to energy levels and bands.
The photon loses the corresponding amount of energy and carries on with the rest, possibly colliding with another electron, and so on.
The excited electron, no falls back to it's equilibrium state, re-emitting the energy as another photon.
This is how flouro materials work as well. They adsorb UV photons (high energy) and re-transmit them as visible light of lower energy, making things look 'brighter'.
Because of this, white objects diffuse light in all directions equally. Glossy white objects is the equivalent of having a really bad, transparent-ish mirror on a white surface, resulting in a combination of both reflection and diffusion.
I think you meant “matte objects”. Diffusion is the result of the surface texture, not color. Nearly all the light you see from a white object is fluoresced rather than reflected. The phosphors in our lights react the same way to create visible light.
No, nearly all of the light coming from a white matt surface is reflected light, in a random direction, not fluorescent light. (you would get a clearly visible tint shift compared to the light source if it was fluoresced light)
Physics brain wasn't working last night.
Of course, absorption and emission spectra.
I stand corrected.
Unless an object is black, it’ll fluoresce and emit all (white) or some combination of colors when struck by light. A shiny black car has the same reflective qualities as a white one but the white one glows even where light isn’t being reflected. Pigment has nothing to do with reflectivity.
This is good information, i assume here are some losses in this process, so i am wondering how much is lost