What is a pentagonal prism? With the development of the economy and the rapid development of various industries, the demand for prisms has also increased. In daily life, we often see the application of pentagonal prisms. Today, we will take a specific look at the explanation of pentagonal prisms, as follows.
The light of a pentagonal prism is incident vertically on either side at a 90 ° angle, then reflected on both sides at a 45 ° angle, and then emitted from the other side at a 90 ° angle. Generally, the angle between the incident and outgoing light is equal to 90 °, which allows the pentagonal prism to rotate the optical axis through 90 °. Therefore, this characteristic of a pentagonal prism can be used to measure the planarity of a large plane, When a pentagonal prism is rotated around the horizontal axis, the emitted light is swept out of a plane in the vertical plane. Conversely, when rotating around the vertical axis, the flatness in the horizontal plane can be measured. When using a laser as the light source, due to the long range of the laser, a large plane can be swept out. This is obviously simple, convenient, and high-precision for flatness measurement in housing construction and large-scale engineering construction, so the demand for pentagonal prisms is increasing.
Due to the inability of the pentagonal prism to achieve internal total reflection based on the critical angle principle, two reflective surfaces on the prism are coated with aluminum film and black paint, and the incident and outgoing surfaces are coated with MgF2 single-layer anti reflection film.