hålkollimator

A hålkollimator, also known as a pinhole collimator, is an optical device used to produce a narrow beam of light or to precisely define a direction. It consists of a small aperture, typically a pinhole, placed in an opaque material. When light passes through this aperture, it is effectively collimated, meaning its rays become parallel. This process is based on the principle that light travels in straight lines.

Hålkollimators are crucial in various scientific and technical applications. In optics, they are used to test the quality of lenses and mirrors by creating a well-defined light source for interferometry or other optical measurements. They can also be employed to calibrate optical systems or to establish a precise line of sight. In some imaging systems, particularly those using X-rays or gamma rays, hålkollimators are used to restrict the field of view and improve image resolution.

The size and shape of the pinhole are critical parameters that determine the degree of collimation and the intensity of the resulting beam. A smaller pinhole generally results in better collimation but also reduces the amount of light passing through, leading to a dimmer beam. Conversely, a larger pinhole allows more light but produces a less collimated beam. The material surrounding the pinhole is usually chosen for its opacity and ability to withstand the conditions of its intended use.