spektrikaamerad

Spektrikaamerad, or spektrala kameror, are imaging devices that capture spectral information for every pixel, producing a data cube with two spatial dimensions and one spectral dimension. This enables material identification and discrimination based on spectral signatures, beyond what conventional RGB cameras can provide.

Principles and methods: They separate light into distinct wavelengths using prisms, diffraction gratings, or tunable filters, and record a spectrum for each pixel. Some systems are snapshot cameras that capture all bands simultaneously; others acquire wavelengths or spatial lines sequentially to assemble the full cube. Detector choices depend on the spectral range, with silicon sensors for visible light and InGaAs or other materials for near-infrared.

Types: Multispectral cameras collect a relatively small number of broad bands, typically in the visible to near-infrared. Hyperspectral cameras acquire hundreds of narrow bands across a wider spectral range, sometimes extending into short-wave infrared. Technologies include filter wheels, tunable filters, dispersive optics, and snapshot sensors with coded masks or microlens arrays to capture spectral information.

Applications: Widely used in agriculture and vegetation monitoring, remote sensing and mapping, mineral and material analysis, industrial inspection and quality control, medical imaging and dermatology, food safety and processing, art conservation and cultural heritage, as well as astronomy and atmospheric research.

Advantages and challenges: The rich spectral data facilitate precise identification and non-destructive analysis, but systems are often expensive, generate large datasets, and require substantial calibration, processing, and expertise. Trade-offs frequently exist among spectral resolution, spatial resolution, and acquisition speed.

Terminology: In Swedish contexts, spektrikaamerad (singular) or spektrikameror (plural) refer to spectral cameras. Related concepts include hyperspektrala cameras and multispektrala cameras.