摘要:
An illumination light communication device includes a power supply unit controlling a load current in a light source unit to be maintained constant based on a dimming signal; an impedance unit series connected to the light source unit; a switch element parallel connected to the impedance unit to connect/disconnect the impedance unit with the light source unit; and a control unit controlling on/off of the switch element to modulate a light intensity of the light source unit such that a binary communication signal is superimposed on illumination light therefrom. The control unit controls the impedance of the impedance unit such that a difference between magnitudes of the load currents respectively when the pulse of the communication signal is superimposed and is not superimposed is maintained constant regardless of a dimming rate of the dimming signal in a range of a dimming rate equal to or greater than a predetermined level.
摘要:
An illumination light communication device includes a light source unit including light emitting elements; a power supply unit controlling a load current flowing through the light source unit to be maintained at a constant; a switch element connected in series to the light source unit; and a control unit configured to control on/off of the switch element to modulate a light intensity of illumination light from the light source unit such that a binary communication signal is superimposed on the illumination light. The control unit has a switching circuit to open/close a path between the light source unit and the power supply unit, controls on/off of the switching circuit based on a dimming signal to perform a dimming control on the light source unit by a PWM control, and allows the communication signal to be superimposed on the illumination light in synchronization with an ON time of the switching circuit.
摘要:
In an insulation type AC-dc converter in which input current from a commercial power supply is converted to obtain insulated direct current, the overall efficiency is raised and the structure is simplified. A multi-resonance type half-bridge DC-DC converter having an insulation transformer T is used as a first converter, and a boosting chopper circuit for power factor improvement is used as a second converter. Hence through multi-resonance operation, increases in losses can be suppressed even when the switching frequency is raised, and because a half-bridge circuit is used, switching elements and similar with lower voltage ratings can be employed, whereby overall efficiency can be increased. Moreover, a voltage substantially similar to the full-wave rectified waveform of the power supply voltage is obtained from the output capacitor at the boosting chopper circuit input, whereby there is no need for a feed-forward circuit across the insulation transformer, and moreover the electrolytic capacitor which had to be provided on the converter input side is unnecessary. This is advantageous for achieving miniaturization and a thin design.
摘要:
In an insulation type AC-dc converter in which input current from a commercial power supply is converted to obtain insulated direct current, the overall efficiency is raised and the structure is simplified. A multi-resonance type half-bridge DC-DC converter having an insulation transformer T is used as a first converter, and a boosting chopper circuit for power factor improvement is used as a second converter. Hence through multi-resonance operation, increases in losses can be suppressed even when the switching frequency is raised, and because a half-bridge circuit is used, switching elements and similar with lower voltage ratings can be employed, whereby overall efficiency can be increased. Moreover, a voltage substantially similar to the full-wave rectified waveform of the power supply voltage is obtained from the output capacitor at the boosting chopper circuit input, whereby there is no need for a feed-forward circuit across the insulation transformer, and moreover the electrolytic capacitor which had to be provided on the converter input side is unnecessary. This is advantageous for achieving miniaturization and a thin design.
摘要:
Light outputs from many LEDs are uniformized and power consumption required for such uniformizing is suppressed, in an LED lighting circuit to be used for illuminating apparatus and the like. Currents flowing from a DD converter to an LED module are detected by a current detection resistor and compared with a reference voltage (Vref) from a reference voltage source by a comparison circuit. Corresponding to the comparison results, a control circuit controls the DD converter, and the currents flowing to the LED module are controlled to be constant currents at the same time. Furthermore, in LED load circuits configuring the LED module, control elements configuring a current mirror circuit are arranged in series, a corresponding control element is permitted to have a diode structure by having a circuit with the highest sum of the LED ON voltages as a reference, the flowing current values of the control elements of the remaining circuits are interlocked, and the LED load circuits are balanced.
摘要:
An illuminating light communication device comprises a constant current source, a smoothing capacitor connected to an output of the constant current source, a load circuit comprising a light emitting diode and connected to the output of the constant current source, a load change element added to the load circuit and thereby partially changing load characteristic of the load circuit, and a switch element configured to determine whether or not the load change element is added to the load circuit in accordance with a binary optical communication signal.
摘要:
An illuminating light communication device comprises a constant current source, a smoothing capacitor connected to an output of the constant current source, a load circuit comprising a light emitting diode and connected to the output of the constant current source, a load change element added to the load circuit and thereby partially changing load characteristic of the load circuit, and a switch element configured to determine whether or not the load change element is added to the load circuit in accordance with a binary optical communication signal.
摘要:
A light source apparatus having a radiator plate having thermally conductive properties and an insulating member coupled to at least one side of the radiator plate having a through hole provided in a side thereof facing the radiator plate. The light source apparatus further including a LED chip installed and thermally coupled to an exposed portion of the radiator plate facing the through hole, an extension inwardly projecting at the through hole from the radiator plate end of the insulating member, and a wiring pattern provided on the insulating member electrically isolated by the insulating member from the radiator plate. The light source apparatus also including bonding wires electrically connecting portions of the wiring pattern on the extension and the electrodes of the LED chip, and a light-transmissive sealing material filling the through hole for entirely encapsulating the LED chip and the bonding wires.
摘要:
An LED luminaire is formed such that a plurality of LED chips are disposed three-dimensionally on an MID (molded interconnection device) substrate in a rectangular plate shape, by mounting three LED chips on bottom face of respective dents provided lengthwise and crosswise in one surface of the MID substrate, the LED chips including at least two types mutually diffferent in luminous color, desirably three types of red, blue and green colors. Any optional light distribution characteristic is made thereby easily obtainable depending on a configuration of the substrate, luminaire module can be thinned, and such delicate color difference as white color and day-light color of luminescent lamps is enabled by mixing the luminous colors of the respective LED chips.
摘要:
A light emitting device comprises: an LED chip mounted in a recess formed in a mounting substrate; a wavelength converting member that is disposed so as to cover the recess and the edge area around the recess and that is excited by light emitted from the LED chip to emit light of a wavelength different from an excitation wavelength; and an emission control member disposed at a light output side of the wavelength converting member so as to allow emission of light coming from an area of the wavelength converting member that corresponds to the recess and to prevent emission of light coming from an area of the wavelength converting member that corresponds to the edge area around the recess. This can prevent variations in color between light emitted from the central part of the wavelength converting member and light emitted from the part of the wavelength converting member that is located on the edge area around the recess of the mounting substrate, thereby reducing unevenness of color on the irradiation surface.