Here are five sources of light that are not hot:
Bioluminescent organisms: Some living organisms, such as fireflies, glow worms, and certain types of marine creatures, produce their own light through a chemical reaction within their bodies. This light emission, known as bioluminescence, does not involve heat.
LED (Light-Emitting Diode) lights: LED lights are highly energy-efficient and produce light without generating excessive heat. They are commonly used in various applications, including lighting fixtures, electronic displays, and indicator lights.
Glow sticks: Glow sticks contain chemicals that, when mixed together, produce a chemical reaction that generates light without heat. They are often used for decorative purposes, in emergency situations, or for fun events.
Electroluminescent panels: Electroluminescent panels are thin, flexible sheets that emit light when an electric current passes through them. These panels can be used for signage, backlighting, or decorative lighting.
Phosphorescent materials: Certain materials, such as phosphorescent pigments or paints, can absorb light energy and re-emit it slowly over time. These materials can glow in the dark after being exposed to a light source, without generating significant heat.
These sources of light provide illumination without the same level of heat production as traditional incandescent or halogen light sources. They are often preferred in applications where minimizing heat generation is important, or for creating unique lighting effects.