What technological addition was introduced to convert unused energy into broader visible light, thereby improving color rendering?

Answer

A phosphor coating on the inside of the outer glass envelope.

The development of the phosphor-coated mercury vapor lamp involved applying a coating that absorbed the lamp's UV radiation and re-emitted it as visible light across a broader spectrum.

What technological addition was introduced to convert unused energy into broader visible light, thereby improving color rendering?

#Videos

The Mercury Vapor Lamp 1901 - YouTube

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