Abstract: There is provided a lighting device usable in a space together with 3D glasses having shutters which alternately block respective translucent surfaces of a pair of lenses at one of a plurality of shutter frequencies. The lighting device includes: a lighting unit which outputs a direct current to a light source; and a dimming control unit which turns on/off supply of the direct current to the light source at a predetermined PWM frequency. Further, the PWM frequency is an integer multiple of the least common multiple of the plurality of shutter frequencies.

Abstract: A lighting device includes: a lighting unit which outputs a direct current; a smoothing unit having a capacitor which smoothes the direct current outputted from the lighting unit and supplies it; and a control unit for performing an intermittent control which alternately repeats a first time period in which the direct current is supplied to the smoothing unit and a second time period in which the direct current decreases to be smaller than that in the first time period. In the lighting device, a product of a frequency (Hz) and a capacitance (?F) of the capacitor is equal to or greater than 0.05 in which one cycle of the frequency corresponds to a sum of the first time period and the second time period.

Abstract: A lighting device is provided for lighting control of an LED module based on an externally provided dimming control signal. A chopper circuit includes a switch coupled across a DC input and an inductor which receives and stores energy when the switch is turned on, and discharges energy to the LED module when the switch is turned off. A control circuit determines a current value to the switch, and compares the current value to a predetermined value. During normal operation, the switch is turned off when the detected current value reaches the predetermined value and turned back on when inductor discharge has completed. During a dimming operation, the normal operation is intermittently disabled in accordance with the dimming control signal. The dimming control signal may be a low-frequency PWM signal, with the lighting output being dimmed as a result of a duty ratio of the PWM signal.

Abstract: A lighting device reliably detects a status (i.e., existence or absence) of a load connection, and enables or disables power output based on the detected load connection status. The device includes a DC-DC converter having input and output terminals, and a DC current conducting element coupled across the output terminals. A load terminal is also coupled across the output terminals and configured to receive an LED unit. A load detection circuit coupled between an input terminal and the load terminal detects the connection status of an LED unit via a DC current passing through the load terminal, and controls a switching operation of the DC-DC converter based on the detected connection status. A diode coupled between the load terminal and the DC current conducting element blocks a DC current path from the input terminals to the load detection circuit through the DC current conducting element.