According to one embodiment, a non-volatile semiconductor memory device comprises memory strings. The drive mechanism can selectively tilt the steering wheel or telescope the steering column in response to input from the driver. A flow connection, starting from the area of the intermediate space between the seals, extends to the interior space and is provided with a nonreturn valve, through which a flow can proceed only in the direction of the interior space. The DSP processes a plurality of electrical signals converted through the OPH whenever the microprocessor has regulated the compensation value of the SA compensation driver, so as to obtain width values of a plurality of focus-error signals. A distance changing unit changes a distance between the liquid-droplet-discharge surface and the optical axis of the beam based on, for example, a diameter of the droplet. The voltage level shifter has an input, switching circuitry, a pass transistor and an output.