摘要:
A planar light source device (1) is provided with a light source unit (4B) wherein a semiconductor light-emitting element (43) is covered with a transparent resin part (44); a light guide body (3) having a side surface (3B) facing the light source unit (4B); and a holding body (5B), which has the light source unit (4B) fixed on one side and the light guide body (3) on the other side, and a space between a transparent resin part (44) and the side surface (3B), and connects the light source unit (4B) and the light body (3). The light source unit (4B) moves with extension and retraction of the light guide body (3). The holding body (5B) holds a distance constant between the transparent resin part (44) of the light source unit (4B) and the side surface (3B) of the light guide body (3) to extension and retraction of the light guide body (3).
摘要:
An LCD apparatus includes an LCD panel to display an image and an LED backlight to illuminate the LCD panel from behind. The LCD panel has first sections divided in a vertical direction and second sections divided in a horizontal direction. The LED backlight includes an LED light source and an edge-type light guide. The LED light source includes LEDs that are arranged along at least one of upper and lower sides of the light guide and are allocated to the second sections, respectively. A brightness of an image displayed in a given second section is used to control a light quantity of the corresponding LED. Each LED radially emits light so that light beams from adjacent ones of the LEDs intersect each other.
摘要:
An LED lighting apparatus includes a triac dimmer 3, a series circuit connected to the triac dimmer and including a primary winding P of a switching transformer T and a switching element Q1, the switching transformer having a plurality of windings, a controller 14 of the switching element, a rectifying-smoothing circuit of a voltage of a secondary winding S of the switching transformer, LEDs 1a to 1n connected to an output of the rectifying-smoothing circuit, a current detector 7 detecting a current of the, a voltage detector 11 configured to output a voltage detection signal of a voltage generated at one of the secondary winding when the first rectifying element is ON, the voltage at the secondary winding being proportional to the phase-controlled AC voltage, and an amplifier 13 amplifying a signal that is based on the current detection signal and voltage detection signal for the controller.
摘要:
A multi-discharge tube lighting apparatus connectable to a power source comprising a first output terminal and a second output terminal respectively outputting voltages of opposite phases, the lighting apparatus comprises first to n-th discharge tube units where n represents an integer of two or more, each of which has a first end connected to the first output terminal and a second end connected to the second output terminal and comprises at least one discharge tube, a first winding, and a second winding, which are connected in series between a first end and a second end. The first winding of the first discharge tube unit is electromagnetically coupled via a transformer to the second winding of the n-th discharge tube unit. The first windings of the second and subsequent discharge tube units are electromagnetically coupled via transformers to the second windings of the previous discharge tube units, respectively.
摘要:
A discharge-lamp lighting apparatus includes series circuits connected to each end of a DC power source, a transformer, FETs Qp1, Qn1, Qp2, and Qn2, and a drive circuit. The drive circuit includes transistors Q1 and Q3 to discharge gate-source capacitances of the Qp1 and Qp2, resistance elements to determine gate potentials of the transistors Q1 and Q3 when the transistors Q1 and Q3 are turned on, transistors Q2 and Q4 to charge the gate-source capacitances of the Qp1 and Qp2, constant current circuits, and switches connected in series with the series circuits of the constant current circuits and resistance elements, respectively, to turn on/off the constant current circuits.
摘要:
(1) An oscillator generates a triangular wave signal whose inclination for charging a capacitor and inclination for discharging the same are the same and which is used to turn on/off FETs Qp1 and Qn1, (2) a signal generation part generates first drive signal in a period shorter than a half period of the triangular wave signal to drive the Qp1, and generates a second drive signal having a pulse width substantially equal to that of the first drive signal and a phase difference of about 180 degrees with respect to the first drive signal, to drive the Qn1 and provide a current to the discharge tube in a direction opposite to the current driven by the first drive signal, and (3) a pulse current generation circuit converts a synchronization pulse voltage signal into a pulse current that alternates between positive and negative current values of the same absolute value at a duty of about 50% and superimposes the pulse current on the triangular wave signal to drive the first drive signal and the second drive signal.
摘要:
A synchronous operating system for operating a plurality of discharge tube lighting apparatuses at the same frequency and same phase includes (1) an oscillator of a triangular wave signal whose inclination for charging a capacitor C2 and inclination for discharging the same are the same, (2) a signal generation part to generate, in a period shorter than a half period of the triangular wave signal, a first drive signal having a pulse width corresponding to a load current, and (3) a signal generation part of a second drive signal having a pulse width substantially equal to that of the first drive signal and a phase difference of about 180 degrees with respect to the same.
摘要:
A gas-discharge lamp igniter is disclosed which has a group of gas-discharge lamps, such as those for LCD backlighting, connected in parallel with one another between the pair of outputs of an AC power supply. Provided one for each lamp to be energized, current-balancing transformers have their secondary windings serially interconnected. The lamps are connected to one of the pair of outputs of the AC power supply via the respective primary windings of the current-balancing transformers and the serial connection of the secondary windings thereof.
摘要:
A discharge lamp lighting apparatus includes a first inverter, a second inverter to output a voltage whose phase is opposite to that of a voltage provided by the first inverter, a discharge lamp connected between a first output terminal of the first inverter and a first output terminal of the second inverter, a first current detection circuit arranged between a second output terminal of the first inverter and a common potential and having a first current detection element and a second current detection element that are connected in series, a second current detection circuit arranged between a second output terminal of the second inverter and the common potential and having a third current detection element and a fourth current detection element that are connected in series, and a protection circuit to detect a current abnormality according to a composite signal of outputs of the second and fourth current detection elements and stop the operation of the first and second inverters.
摘要:
A discharge lamp lighting apparatus includes a switch circuit for DC/AC converting, a discharge lamp connected to a secondary winding of a transformer, a current detector detecting an AC output current of the discharge lamp, an error amplifier outputting an error signal to a detected current, a control circuit generating control signals that turn on/off the switching elements in such a way as to control the AC output current at a predetermined value, and a time division signal generator generating a time division signal at the start of an ON/OFF operation of the switching elements, wherein the time division signal delays a change in a burst dimming signal or has a predetermined inclination on the burst dimming signal. The error amplifier changes the error signal according to the time division signal from the time division signal generator.