Spectral Resolution

Spectral resolution refers to the ability of a remote sensingRemote SensingRemote sensing is the science of collecting data about Earth's surface without direct physical contact, primarily usi... sensor to define fine wavelength intervals across the electromagnetic spectrum. It is characterized by the number of bands a sensor records and the width (bandwidth) of each band. Narrower bands provide finer spectral discrimination, enabling more precise identification of surface materials, while broader bands collect more energy per band, improving signal quality. Spectral resolution categoriesPanchromatic sensors capture a single wide band across the visible spectrum. Multispectral sensors record 4-12 discrete bands (e.g., Sentinel-2 with 13 bands). Hyperspectral sensors capture hundreds of narrow contiguous bands (e.g., AVIRIS with 224 bands at ~10 nm width). Ultraspectral sensors exceed 1,000 bands for laboratory-grade spectral measurement. Impact on applicationsHigher spectral resolution enables identification of specific minerals, detection of subtle vegetation stress, discrimination between crop species, and identification of water pollutants. However, narrower bands reduce the amount of energy collected per band, potentially decreasing signal-to-noise ratio and requiring trade-offs in sensor design. Spectral resolution is a fundamental characteristic that determines what information can be extracted from remote sensing imagery. The choice between broad multispectral and narrow hyperspectral approaches depends on the application's requirements for spectral discrimination versus signal strength and data volume.