Many LED semiconductor chips are potted in clear or colored molded plastic shells. The plastic shell has three purposes:
- Mounting the semiconductor chip in devices is easier to accomplish.
- The tiny fragile electrical wiring is physically supported and protected from damage.
- The plastic acts as a refractive intermediary between the relatively high-index semiconductor and low-index open air.
The third feature helps to boost the light emission from the semiconductor by acting as a diffusing lens, allowing light to be emitted at a much higher angle of incidence from the light cone than the bare chip is able to emit alone.
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