The respective proportionality constants of magnetic force by magnetic field producing portion for biasing the plug in the direction of insertion and resilient force by a spring mechanism for biasing the plug in the direction of extraction are adjusted in such a manner that the resilient force is greater than the magnetic force until the plug pin reaches an intermediate insertion position at which the plug pin comes into proximity to or separates from the socket contact, whereas the magnetic force is greater than the resilient force at a position at which the plug pin is inserted into a complete insertion position for a hot-line connection to the socket contact. The plug pin in the vicinity of the intermediate insertion position, at which there is a possibility of occurrence of an arc discharge, is ejected by the resilient force.

The present disclosure relates to a starting device for a CDM lamp, comprising: a full-bridge inverter, which at least provides an output as a starting power source to initiate the CDM lamp to work normally; a driving circuit for driving the full-bridge inverter; a single-chip microcomputer, which is connected to the driving circuit; an ignition determining module, one end of which is connected to the full-bridge inverter to sense whether the output of the full-bridge inverter has powered on the CDM lamp, so as to determine whether ignition of the CDM lamp succeeds and then output a result of the determining to the single-chip microcomputer via the other end. The present disclosure provides a novel starting device for a CDM lamp, which facilitates determining whether starting of the CDM lamp succeeds and also facilitates enhancement of successful rate of starting the CDM lamp subsequently.

The respective proportionality constants of magnetic force by magnetic field producing portion for biasing the plug in the direction of insertion and resilient force by a spring mechanism for biasing the plug in the direction of extraction are adjusted in such a manner that the resilient force is greater than the magnetic force until the plug pin reaches an intermediate insertion position at which the plug pin comes into proximity to or separates from the socket contact, whereas the magnetic force is greater than the resilient force at a position at which the plug pin is inserted into a complete insertion position for a hot-line connection to the socket contact. The plug pin in the vicinity of the intermediate insertion position, at which there is a possibility of occurrence of an arc discharge, is ejected by the resilient force.

The present disclosure relates to a starting device for a CDM lamp, comprising: a full-bridge inverter, which at least provides an output as a starting power source to initiate the CDM lamp to work normally; a driving circuit for driving the full-bridge inverter; a single-chip microcomputer, which is connected to the driving circuit; an ignition determining module, one end of which is connected to the full-bridge inverter to sense whether the output of the full-bridge inverter has powered on the CDM lamp, so as to determine whether ignition of the CDM lamp succeeds and then output a result of the determining to the single-chip microcomputer via the other end. The present disclosure provides a novel starting device for a CDM lamp, which facilitates determining whether starting of the CDM lamp succeeds and also facilitates enhancement of successful rate of starting the CDM lamp subsequently.

A discharge lamp driving device includes: a discharge lamp drive unit configured to supply a drive current to a discharge lamp having two electrodes; a voltage detection unit configured to detect an inter-electrode voltage of the discharge lamp; and a control unit configured to control the discharge lamp drive unit, wherein the control unit executes first measurement drive in which a polarity of the drive current is maintained constant at a first polarity, the voltage detection unit measures the inter-electrode voltage multiple times in a first measurement period in which the first measurement drive is executed, and the control unit determines states of the electrodes of the discharge lamp based on a plurality of the inter-electrode voltages measured in the first measurement period.

A light source drive device includes a supply unit that supplies a high-frequency first drive signal and a second drive signal whose frequency is lower than a frequency of the first drive signal to a discharge lamp which has a pair of electrodes, and a control unit that controls the supply unit so that the first drive signal and the second drive signal of fixed durations are alternately supplied and that controls the supply unit so that the first drive signal is supplied in a case where a voltage between the pair of electrodes is below a threshold.