A high-gain screen can be made as a sandwich of a hologram and a retroreflective screen material. When a hologram is used in front of the screen instead of the screen material alone, the position of high-brightness viewing can be moved to any desired angle rather than being directed back along the projection beam.

Despite providing robustness, high-gain observers impose a peaking phenomenon, which may cause instability, on the system states. In this paper, an adaptive saturation is proposed to attenuate the undesirable mentioned phenomenon in high-gain observers. A real-valued and differentiable sigmoid function is considered as the saturating element whose parameters (height and slope) are adaptively tu...