Since the invention of electric light, life has become more convenient and rich. But electric lamps can only convert a small part of electric energy into visible light, and most of the rest is wasted in the form of heat energy. The heat rays of electric lamps are harmful to people's eyes. So, is there a light source that only emits light without heating? Humans have turned their attention to nature again.

In nature, many creatures can emit light, such as bacteria, fungi, worms, mollusks, crustaceans, insects and fish, and the light emitted by these animals does not produce heat, so it is also called "cold light".

Fireflies are one of many luminous animals. There are about 65,438+0,500 species of fireflies. Their luminescent colors are yellow-green, orange, and their brightness is different. Fireflies emit cold light, which not only has high luminous efficiency, but also is generally soft, suitable for human eyes, and the light intensity is relatively high. Therefore, bioluminescence is an ideal light source for human beings.

Scientists found that the luminous device of fireflies is located in the abdomen. This light emitter consists of three parts: light emitting layer, transparent layer and reflecting layer. There are thousands of luminescent cells in the luminescent layer, all of which contain fluorescein and luciferase. Under the action of luciferase, fluorescein combines with oxidation to emit fluorescence with the participation of intracellular water. The luminescence of fireflies is essentially a process in which chemical energy is converted into light energy.

As early as 1940s, people created fluorescent lamps on the basis of studying fireflies, which greatly changed the lighting sources of human beings. In recent years, scientists first isolated pure fluorescein from fireflies, then isolated luciferase, and then synthesized fluorescein artificially by chemical methods. Biological light source composed of fluorescein, luciferase, ATP (adenosine triphosphate) and water can be used as a flash lamp in mines filled with explosive gas. Because this lamp has no power supply and does not produce magnetic field, it can be used to clear magnetic mines under the irradiation of biological light source.

Now, people can get cold light similar to biological light by mixing some chemicals for safe lighting.