just thoughts . . .
when you grind off the dome, it becomes basically a point source of light, eminating in all 360*, and other than the bright emitter point they suddenly seem very dim
because of no concentration of light.
the phosphors, and the fact that there is a metal base (tiny as it is) still puts most of the light foreward (180*), but lots still falls out the back.
when you put a point souce under diffusion, it doesnt make that much difference if its ground flat or not, that One area of the diffusion still gets more light up than the rest (that glowing spot). . . UNTIL you back the source away from the diffusion. SO the distance from the diffusion will be more important than excessive difusions, and cliping the dome, to get the blending.
that all EXCLUDES completly the very expencive linear diffusion which costs about 25$ a square foot, and acts like ,little strung out light fibers , shooting the light in ONE linear direction. then you use 2 sheets, one shooting light horizontally, one shooting light vertically. seen that behind the LCD screens
and your completly limited for SPace right? between the location of the lighting and the top covering. so distancing the leds is going to be impossible :-(
pirannah leds, the square ones, that sit low, would be a good CHEAP choice for this kinda thing . . . because.
1) they sit low
2) they have more heat removal capacity due to design
3) they last longer because of ability to remove heat
4) they are less directional, comming in 60-80-120* types
5) they are still cheap
things like lo-moon would be leds that would last MANY times longer than 5mm leds, when driven low, and they are low (height) and very diffuse, with no "dome" but they would be very expencive comparably, and high powered leds.
we have wedged many 5mm led ARRAYS into things only to have them die over time. 5mm leds suck bad, at least nitchita ones last more time. but if i was going to put a lot of time into a project, i would do anything to try and avoid using them stupid little things
. or run them nice and low.
after you assemble 100leds together by HAND, and they dont last, its the last time you try and do that
that brings up the 50 different type of difusion. and light pipes and all that other stuff, which gets rather complex.
the "frosted" or white difusions would be best for keeping the spots of light down, as they will internally pass the light faster, but the clear diffusions dont waste so much light at all to move it around, like the clearer lucite junk for florescent fixtures as compared to the white frosting ones.
so if you have distance from the point source, the clear or crystal type of difusion would be a good first difusion, If you have no ability to get the point source away from the difusion, that white stuff would be the thing to use.
lucite light pipes are amazing, and potentially you could put high powered leds at both ENDS of a light pipe, and even have heat synking on the 2 ends. the ammount of light that spills out the sides of cheap light pipes, is enough to light up in a blended way, frosting the edge of it will increase the departure of light.
SO
some cheap plastic tubes from tap plastics might be sperimented with to use as psudo light pipes. i piddled with thier clear 1/2" and 3/4" Tubes (not solid) and even the small ones did an amasing job of passing light from one end to 6feet away to the other end.
and if you need cheap diffusion and white frosted thick plastic diffusion, you should see if you can go to a Tap Plastics at least to look. with led flashlight in hand to test (of course)
on the other hand, you could reverse all that, and do like they did with the coffee table and not worry about a blended overall lighting, and purposfully have there BE spots, for effect, mabey add in COLOR and all so it even more looks like it was designed that way.
