Careful with those 'synonyms.' :) "Refraction" of light is, simply put, the '(re)breaking' of light: it's bent when it passes from one medium to another at an angle (becase its speed changes). It's an effect you commonly see when you put, say, a stick into the water: the stick will appear to be broken ('fractured') at the point of entry into the water. That's refraction. Or when light passes thru a prism. Anyway, on to your question. Assuming you mean 'reflection,' the color blue absorbs more light than white; so, theoretically, your luminance (= state or quality of radiating or reflecting light) will be lower. In practice you'll hardly notice it, though. Light bulbs tend to emit a red-ish light, rather than purely white. So, any light bulb specifically made to emit a purer white light would be okay.

I'd paint it white as that color reflects light which is important at night.

"if i paint my bedroom celling sky blue,the will the electric light become an unexpected color? it kind of worrys me,because I sometimes read in my bedroom." {corrected sentences} _____________________________________________________________ {responce} i would aviod painting ceilings anycolor other than white. if you want more variety in your room you might want to consider double color painting, i.e : one wall side light the next slightly darker and then the other light again and then darker . i hope you understand,.... um here is an example: http://www.exinteriordesign.com/interior-design-combination-red-and-white-living-rooms/ or http://images.google.com/imgres?imgurl=http://1.bp.blogspot.com/_C4L8XftIrHU/SxmWVDq1IcI/AAAAAAAAD5Y/tb68gxyYgg0/s400/bedroom-color-soft-green-2.jpg&imgrefurl=http://bedroominteriordesigning.blogspot.com/2009_12_01_archive.html&usg=__pys-tzw2NzOt9faT1440SeNNMOQ=&h=300&w=400&sz=22&hl=en&start=16&um=1&itbs=1&tbnid=kMxoX8Yl2aLmFM:&tbnh=93&tbnw=124&prev=/images%3Fq%3Delegant%2B2%2Bcolor%2Bbedrooms%26hl%3Den%26rlz%3D1C1CHMB_enUS342US342%26sa%3DX%26um%3D1 hope this helps and give you ideas let me know if i can help :) i love design! :D

change the ceiling light? http://www.heals.co.uk/content/ebiz/heals/invt/515367/515367_m.jpg something like that should be fine

you can still read in your bedroom if that bother you. put some table lampshade. cowboy...