polarisationskällor

Polarisationskällor refer to phenomena or devices that produce polarized light. Light is an electromagnetic wave that oscillates in all directions perpendicular to its direction of propagation. When these oscillations are restricted to a particular direction or plane, the light is said to be polarized.

Several natural and artificial sources can create polarized light. One common natural source is scattering. When sunlight encounters particles in the Earth's atmosphere, it gets scattered. This scattered light is partially polarized, which is why polarizing sunglasses can reduce glare from surfaces like water. Reflection from non-metallic surfaces, such as roads or water, also produces polarized light. The angle of incidence plays a crucial role in the degree of polarization.

Artificial sources for polarized light include polarizing filters, which are commonly used in cameras, sunglasses, and scientific instruments. These filters work by absorbing light waves oscillating in one direction while allowing waves oscillating in a perpendicular direction to pass through. Another method is birefringence, a property of certain materials that causes light to split into two rays polarized at right angles to each other. Lasers can also produce polarized light, often with a specific polarization state inherent to their design. Dichroism is another principle where a material absorbs light differently depending on its polarization direction, leading to polarized output.