Why is a 10mw laser pointer more powerful than a 20mw light bulb?

Lasers are different from ordinary light beams. Lasers are also called "stimulated radiation light amplification". It was originally proposed by Einstein. The principle is that electrons in atoms are excited to release photon beams with highly consistent optical characteristics. Compared with ordinary light sources, lasers are single The color, direction, and brightness are better. As a common pointing tool, laser pointers are very common in conference rooms. Pet owners often use them to tease cats and dogs. Outdoor astronomy enthusiasts use it to indicate stars. These laser pointers are generally very small, only a few milliwatts. It is often these inconspicuous little toys that cause irreversible physical injuries. Photons are elementary particles that carry energy. We can see light because our eyes receive the photon signal. Most of the light that we are exposed to is soft and divergent. According to the inverse square law, at a certain distance from the light source, the number of photons received by the eyes is limited, which will neither cause irritation nor cause harm, so we do not look directly at the bulb. Will produce discomfort.