Complex sentence: A pyranometer is a type of actinometer used to measure broadband solar irradiance on a planar surface and is a sensor that is designed to measure the solar radiation flux density (in watts per metre square) from a field of view of 180 degrees.
Split into simpler sentences: A pyranometer is a type of actinometer used to measure broadband solar irradiance on a planar surface. In other words: a pyranometer is a sensor that is designed to measure the solar radiation flux density (in watts per metre square) from a field of view of 180 degrees.