Abstract: An electronic package and a manufacturing method thereof are provided, in which an electronic structure and a wall structure surrounding the electronic structure are disposed on a carrier structure, a heat conducting layer is formed on the electronic structure, and the wall structure and the heat conducting layer are covered by a heat dissipation element. Therefore, a thermal stress can be effectively dispersed by the arrangement of the wall structure, such that a warpage of the electronic structure and a heat dissipation body can be effectively controlled.

Abstract: An electrophotographic device uses a closed loop controller that receives a feedback signal from an encoder connected to the OPC drum to improve the rotational velocity control of the drum. The encoder provides the rotational position or angular velocity of the drum to the closed loop controller as the feedback signal. In one embodiment, the electrophotographic device uses a closed loop controller that incorporates a model of the human visual system, such as the human contrast sensitivity function, to help reduce noticeable banding artifacts. The human contrast sensitivity function incorporated into the primary control loop helps filter out low frequency and non-periodic drum rotational velocity fluctuations in producing banding artifacts. The electrophotographic device may also include a repetitive controller in a secondary control loop to help reduce the effect of periodic drum rotational velocity fluctuations in producing banding artifacts.

Abstract: Systems and methods for reducing banding artifact in electrophotographic devices are provided. One such electrophotographic device uses a closed loop controller that receives a feedback signal from an encoder connected to the OPC drum to improve the rotational velocity control of the drum. The encoder provides the rotational position or angular velocity of the drum to the closed loop controller as the feedback signal. Optionally, the electrophotographic device uses a closed loop controller that incorporates a model of the human visual system, such as the human contrast sensitivity function, to help reduce noticeable banding artifacts. The human contrast sensitivity function incorporated into the primary control loop helps filter out low frequency and non-periodic drum rotational velocity fluctuations in producing banding artifacts.