A pot includes a hollow body and a lid detachably mounted on the hollow body to cover the open end. In an example, the punch tool may include a malleable shaft and a finger grip body configured to encompass at least part of a shaft of a finger button. The first sub pixel includes a first switching element and a first boosting switching element, the first switching element is connected to a first liquid crystal capacitor, a gate line, an m-th data line and a first electrode of the first LC capacitor, and the first boosting switching element is connected to the boosted voltage line, and \u2018m\u2019 is a natural number. The digital signal processors process pixel data acquired by selected pixel subsets of the at least two digital cameras to generate pointer characteristic data when a pointer exists in the acquired images.