Return of incandescent light bulbs as MIT makes them more efficient than LEDs - by surrounding the filament with a special crystal structure in the glass they can bounce back the energy which is usually lost in heat, while still allowing the light through

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Return of incandescent light bulbs as MIT makes them more efficient than LEDs - by surrounding the filament with a special crystal structure in the glass they can bounce back the energy which is usually lost in heat, while still allowing the light through