The green pointer sees the stars

In addition, the qualified Laser pointer must emit monochromatic light, even if it passes through the prism, there will be no dispersion phenomenon, while the colored light emitted by ordinary color lamps is often a mixture of the three primary colors of red, green and blue. The polychromatic light will “appear” as soon as it passes through the prism. The star pen generally uses a green laser pointer. The working medium of the laser pointer is divided into solid (such as lithium cesium triborate crystal) and gas (such as carbon dioxide). The green light is generally solid-state laser, and the main components are excitation source, condenser cavity, and resonant cavity mirror. The use of green light as a star pen is not because the light itself has any special features, but because the human eye is most sensitive to the perception of green light. Even the 5mW (IIIA) low-power green laser can be used at night with strong light pollution. Can appear very clear. In addition, the beams emitted by all qualified laser pointers have no difference except the brightness under strong light environment-no matter how high the power of the laser pointer is, the beams emitted towards the sky will suddenly break at the same height. "Drop", this is a visual phenomenon produced under the "Tyndall Effect". This means that even if you buy a cheap laser pointer for tens of dollars, as long as it emits green light, you will surely see a straight and bright "green line" pointing towards the sky when you shoot it toward the sky.

2021-09-03 11:12:14