The invention relates to a control system to which a state vector representing the states of a controlled system is applied. The memory cell includes a first electrode, a second electrode, and a variable resistance layer which is disposed between the first electrode and the second electrode. Injection of the electronic charge is controlled through one or more switching transistors. The rectifying element and charge storage element may help to reduce ringing at an output terminal of the circuit during normal operation and reduce the likelihood of exceeding a breakdown voltage between current-carrying electrodes of a switching element within the circuit during a switching operation. The laser beams emitted from the corresponding two laser chips are refracted by the main part of the lens.