reflectance
Noun: The ratio or fraction of incident radiant energy (such as light or other electromagnetic radiation) that is reflected by a surface, rather than being absorbed or transmitted through it. It is a measure of a surface's reflectivity.
"Reflectance" is a technical term used primarily in physics, optics, engineering, and earth sciences (e.g., remote sensing). It describes a quantifiable physical property of a material's surface. * The reflectance of a material depends on factors like the wavelength of the incident radiation and the angle of incidence. * High reflectance means a surface reflects most of the light, like a mirror. * Low reflectance means a surface absorbs most of the light, like black asphalt.
- Scientists measured the reflectance of the new solar panel coating to optimize its efficiency.
- Snow has a very high albedo, which is a measure of its reflectance of sunlight.
- The satellite data analyzes the spectral reflectance of vegetation to monitor crop health.
- Spectral Reflectance: Reflectance measured as a function of wavelength. This is crucial for identifying materials via remote sensing.
- Bidirectional Reflectance Distribution Function (BRDF): A more advanced concept describing how reflectance depends on both the incoming and outgoing directions of the light.
- Reflectivity (n.): Often used synonymously with "reflectance," though it can sometimes refer more generally to the capability of a surface to reflect.
- Albedo (n.): In astronomy and climatology, the reflectance of a planet or surface across all wavelengths of sunlight.
- Reflective (adj.): Having the property of reflecting light or other radiation.
- Reflection factor
- Reflectivity (in many contexts)
The core meaning is strictly the ratio of reflected to incident energy. It is not simply the act of reflecting (which is "reflection"). It is a dimensionless number, typically expressed as a percentage or a value between 0 and 1.
- the fraction of radiant energy that is reflected from a surface