A power conversion device according to one embodiment of the present invention comprises: a plurality of converters comprising at least one upper switch and at least one lower switch, and respectively connected to a plurality of cell strings; and an auxili...

An optical system according to an embodiment includes first to third lenses disposed along an optical axis from an object side to a sensor side direction, wherein the first lens has a meniscus shape convex toward the object side, and satisfies 1.7≤nt_≤...

A vehicle charging device according to the present embodiment comprises: an amplitude detection unit that detects a magnitude of a grid voltage being inputted to the vehicle charging device; a frequency detection unit that detects a frequency of the grid v...

A lens curvature variation apparatus according to an embodiment includes: a liquid lens including a common electrode and a plurality of individual electrodes; a lens driver configured to apply a voltage to the common electrode and the plurality of individu...