A smart battery charger having a plurality of charging stations for simultaneously charging a plurality of batteries, such as vehicle batteries, in an efficient manner without overcharging by compensating for the current state of charge and temperature of each one of the batteries while indicating a status of the batteries to an operator. The display rack includes a frame which supports one or more of the shelves. The cavity layer has quantum dots embedded therein for realizing an electrically pumped microcavity emitter. Until the focus lens reaches a second threshold value position, the focus lens is moved on the basis of a phase difference AF evaluation value which is output from a phase difference imaging element and is obtained from a signal of an area corresponding to the set focusing target area. The shields being compatible for use in conjunction with saddle, tilted coils or multi-layered tri-axial coils to produce a pure transverse magnetic dipole electromagnetic field.