Abstract: Phase functions for fibrous layer are obtained for two types of fiber orientation:randomly oriented in space and randomly oriented in a plane parallel to the boundary surfaces of the layer.Two types of incident radiation are considered,namely,the radiation normal to the boundaries and the diffuse radiation.The phase functions for the fibrous layer are derived as a function of the polar angle measured within a coordinate system fixed to the fibrous layer.The effects of the type of incidence,size parameter,fiber orientation and complex refractive index are studied.

Key words: thermal radiation, scattering, fibrous layer, orientation, phase function