Abstract: Disclosed is a universal input voltage detection system for a flyback converter having a transformer coupled between an input and an output of the flyback converter. The transformer includes a primary winding coupled to the input of the flyback converter to receive an input voltage and a secondary winding coupled to the output of the flyback converter. The universal input voltage detection system comprises a controller, coupled to a switch, at a primary winding side of the transformer. The switch is coupled to the primary winding of the transformer and a current through the primary winding is generated when the switch is turned on. The controller is configured to operate in either continuous conduction mode (CCM) or discontinuous conduction mode (DCM) and indirectly detect the input voltage to the flyback converter based on the current through the primary winding generated while the switch is turned on.

Abstract: Methods, systems, and apparatus, for optical depolarization. One optical depolarizer includes a light-combining module comprising a birefringent prism, wherein an optic axis of a first crystal of the birefringent prism forms a 90° angle with an optic axis of a second crystal of the birefringent prism; and a depolarization module, wherein the depolarization module is disposed at a light emitting end of the light-combining module, the depolarization module comprising a light splitting component and a light-combining component disposed at an emitting end of the light-splitting component, and a delayer disposed between the light-splitting component and the light-combining component, wherein the delayer is disposed on an emitting optical path of the light-splitting component.

Abstract: Methods, systems, and apparatus, for optical depolarization. One optical depolarizer includes a light-combining module comprising a birefringent prism, wherein an optic axis of a first crystal of the birefringent prism forms a 90° angle with an optic axis of a second crystal of the birefringent prism; and a depolarization module, wherein the depolarization module is disposed at a light emitting end of the light-combining module, the depolarization module comprising a light splitting component and a light-combining component disposed at an emitting end of the light-splitting component, and a delayer disposed between the light-splitting component and the light-combining component, wherein the delayer is disposed on an emitting optical path of the light-splitting component.