Abstract: A light fixture includes a ballast operable to drive a light source of the light fixture. The ballast includes a DC driver circuit and an output current limiting circuit. The output current limiting circuit is operable to minimize current overshoot in the event that an output of the ballast is shorted such as if the light source fails in a short circuit condition. The output current limiting circuit includes an output switch for limiting the current to the load (e.g., light source) and a control circuit. The control circuit senses the short circuit and clearing of the short circuit and controls the output switch accordingly to prevent excess output current to the shorted circuited load.

Abstract: A display device including a transmission display panel, a first backlight module, a first polarizer, and a reflective polarizer is provided. The first backlight module includes a first light guide plate and a light emitting unit. The first light guide plate has a first surface, a second surface opposite to the first surface, and a first light incident surface connecting the first surface and the second surface. The first surface is between the second surface and the transmission display panel. The light emitting unit is disposed beside the first light incident surface. The transmission display panel is between the first polarizer and the first surface. The second surface is between the first surface and the reflective polarizer.

Abstract: A bobbin apparatus and associated magnetic component is configured to reduce gap losses associated with a core air gap in a bobbin-wound magnetic component such as an inductor or transformer. The bobbin includes a step structure protruding from the winding surface between bobbin ends. The step is operable to provide spacing between the conductive windings disposed on the bobbin and the core air gap inside the bobbin axial passage. The spacing reduces stray flux interactions with the conductive winding, thereby reducing gap losses and preventing undesirable heating of the winding and core. Additional winding configurations and methods for use with the bobbin apparatus are also provided.

Abstract: A light source module including an optical film and at least one light source unit is provided. The light source unit and the optical film enclose a space. The light source unit includes a reflecting device, at least one light bar, and a collimated unit. The reflecting device is disposed under the optical film. The light bar includes a plurality of light-emitting elements arranged along a third direction. The collimated unit extends along a direction parallel to the third direction and includes an upper reflective portion and a lower reflective portion. A shortest distance between one end of the lower reflective portion located adjacent to the reflecting device and the optical axis of the light-emitting elements along a second direction is defined as a first half light-emitting width, which is gradually increased along the third direction from a center portion of the collimated unit towards two sides thereof.

Abstract: A light source module including an optical film and at least one light source unit is provided. The light source unit and the optical film enclose a space. The light source unit includes a reflecting device, at least one light bar, and a collimated unit. The reflecting device is disposed under the optical film. The light bar includes a plurality of light-emitting elements arranged along a third direction. The collimated unit extends along a direction parallel to the third direction and includes an upper reflective portion and a lower reflective portion. A shortest distance between one end of the lower reflective portion located adjacent to the reflecting device and the optical axis of the light-emitting elements along a second direction is defined as a first half light-emitting width, which is gradually increased along the third direction from a center portion of the collimated unit towards two sides thereof.

Abstract: A driver circuit (e.g., an LED driver circuit) provides power to a load (e.g. an LED light source) from a DC power rail. A self-oscillating current fed parallel resonant inverter is configured to connect to the DC power rail, receive DC power from the DC power rail, and provide an AC output signal. A current limiting circuit is connected to the self-oscillating current fed parallel resonant inverter. The current limiting circuit receives the AC output signal from the self-oscillating current fed parallel resonant inverter and provides an AC current signal as a function of the DC current provided to the load by the driver circuit. The rectifier receives the AC current signal from the current limiting circuit and provides a DC current to the load.

Abstract: A light emitting unit includes a light source device and a reflector. The light source device extends in parallel with an extension direction, and is capable of providing a light beam. The reflector is configured under the light source device and extends in parallel with the extension direction. The reflector has a first protrusion and a pair of second protrusions located on two sides of the first protrusion, the first protrusion has a peak portion and two trough portions, the second protrusion has a peak portion and a trough portion, and the two trough portions of the first protrusion are respectively connected to the trough portions of the two second protrusions to provide a fluctuant reflection surface, and a height of a cross section contour of the pair of the second protrusions in parallel with the extension direction is decreased from a center to two ends of the reflector.

Abstract: A backlight module including an LGP, an optical film, a first light source is provided. The LGP has a bottom surface, a light emitting surface, a first light incident surface, and microstructures. Each microstructure is recessed into or protrudes out of the bottom surface and includes at least two structural units. A section line of each structural unit on a first reference plane is a curve, and the curve has a peak point. A distance between two peak points of two adjacent structural units along a first direction is greater than 0 and smaller than a half of a total width of the two structural units along the first direction. Each microstructure has a symmetric plane perpendicular to the light emitting surface and the first light incident surface. The optical film is located on the light emitting surface. The first light source is located beside the first light incident surface.

Abstract: A transformer apparatus provides a primary winding and a secondary winding. The primary winding is divided into multiple primary winding layers. Each primary winding layer includes a number of primary layer turns. The secondary winding includes several secondary winding layers. In some embodiments, the transformer includes alternating primary and secondary winding layers wound around a bobbin structure. At least one secondary winding layer is positioned adjacent a primary winding layer. In some embodiments, the number of primary layer turns in each primary winding layer is equal to the total number of primary winding turns divided by the number of primary winding layers. A method of winding a transformer is also provided.

Abstract: A power line communication system and signaling protocol is usable for quick dimming of an electronic ballast. An encoding circuit transmits message frames having encoded control signals across a AC power line. Each of a first set of frames includes a bit pattern corresponding to a lighting zone, and a second set of frames includes hamming-encoded bit patterns corresponding to respective hexadecimal digits of a dimming level for the lighting zone. A ballast in a first (quick-dim) configuration detects the second set of frames, decodes the hamming-encoded digits and immediately adjusts the ballast output to the desired power level. The ballast in a second (normal) configuration determines the desired power level based on a pattern density in the first set of frames, and adjusts the output current of the ballast accordingly. If the ballast of the first configuration fails to detect the second set of frames, it defaults to pattern density recognition.

Abstract: An LED driver circuit is provided for driving a multi-channel LED string with constant and balanced current. The driver circuit includes a half-bridge inverter and a resonant tank circuit in a power stage. An isolating (first) transformer includes a primary winding coupled between a resonant tank output and circuit ground and a plurality of secondary windings, while a balancing (second) transformer includes a plurality of balancing windings. A plurality of output stages each provide an output power to a respective load, and each of the output stages further includes one of the balancing windings of the balancing transformer and one of the secondary windings of the isolating transformer coupled in series, and a rectifier circuit coupled to an output end of the series coupled windings. In an embodiment, an impedance value of the balancing transformer is further configured to be greater than three times a maximum load impedance value.

Abstract: A light fixture includes a converter operable to drive a light source of the light fixture. The buck converter is operable to provide a predetermined average current to the light source or load. A switch of the buck converter is located in the low side of the buck converter such that a controller of the buck converter may drive the switch directly without the use of an isolation transformer. The buck converter controls operation of the switch based on current through the switch and current through the primary inductor of the buck converter.

Abstract: A mounting apparatus for a light emitting diode module provides a support structure for attaching a light emitting diode module directly to a light bulb in a lighting system. A bulb bracket includes a bulb clip that can be mechanically attached to a conventional bulb such as a fluorescent, neon or incandescent light bulb. A light emitting diode module can be secured to the bulb bracket using a module clip or another attachment disposed between the bracket and the module. Additional light emitting diode support structures include a mounting bar securable directly to a light bulb or other structure in a lighting system such as a sign box wall. An expandable support bracket is also provided for supporting one or more light emitting diode modules.

Abstract: A display device includes a display panel having an active display area, an optical film set, a light source module, and a frame. The light source module includes a light guide plate (LGP) and a light source adjacent to a side surface of the LGP. The optical film set is located between the display panel and the LGP. The frame disposed between the LGP and the optical film set extends to the LGP and covers a portion of the LGP. The frame has a first surface carrying the optical film set, a second surface facing to the light emitting surface, and a chamfered inclined surface. The chamfered inclined surface is within the active display area and connects the first and second surfaces. An extending distance of the first surface in the active display area is smaller than an extending distance of the second surface in the active display area.

Abstract: A backlight module includes a light guide plate having a bottom surface, a light emitting surface, a first light incident surface, and microstructures. Each microstructure recesses into or protrudes from the bottom surface and has a first and a second surfaces. The first and the second surfaces of at least one of the microstructures are located on two sides of a first reference plane parallel to the first light incident surface. A section-line of each first surface on a second reference plane perpendicular to the first light incident surface and perpendicular to the light emitting surface is a straight line. A first angle between each first surface and a third reference plane parallel to the light emitting surface in the light guide plate is between 0 degrees and 20 degrees, and a thickness of each microstructure is between 0 micrometers and 20 micrometers.

Abstract: An LED lamp device includes a plurality of LED elements separately mounted on a substrate and effective to emit light having a first wavelength. A fluorescent element includes a fluorescent material excitable by light emitted from the LED elements to emit light of a second wavelength, and is arranged to cover each LED element with no gaps provided between the fluorescent element and the substrate. The fluorescent element is shaped in accordance with the positioning of the LED elements and the spaces defined there-between such that a proportion of light of the first wavelength with respect to light of the second wavelength is substantially uniform irrespective of light exit direction.

Abstract: A core apparatus for a magnetic component includes first and second E-cores stacked with legs extending in the same direction. The first E-core includes a middle first core leg having a middle first core leg length, and the second E-core includes a middle second core leg having a middle second core leg length greater than the middle first core leg length such that a step is formed between the distal ends of the middle legs of the first and second E-cores. A third E-core may be positioned opposite the stacked first and second E-cores forming a stepped air gap between the middle first and second core legs and the middle third core leg.

Abstract: A light fixture includes a converter operable to drive a light source of the light fixture. The buck converter is operable to provide a predetermined average current to the light source or load. A switch of the buck converter is located in the low side of the buck converters such that a controller of the buck converter may drive the switch directly without the use of an isolation transformer. The buck converter controls operation of the switch based on current through the switch and current through the primary inductor of the buck converter.

Abstract: A light source module is provided, which includes at least one light emitting unit and at least one light guide element. The light emitting unit includes a light source and a lens structure. The light source is used for emitting a light beam. The lens structure has a bottom surface, a top surface opposite to the bottom surface, and a first surface connecting the bottom surface and the top surface. The bottom surface has a first recess and a second recess connecting the first recess and the first surface. The top surface has a third recess. The light guide element includes at least one opening and a plurality of first optical micro-structures disposed beside the opening. The light emitting unit is disposed in the opening. The light beam passes through the lens structure and enters the light guide element via the opening.

Abstract: A touch panel including a transparent substrate, a touch module and a flexible circuit board is provided. The touch module is disposed on the transparent substrate. The flexible circuit board has a bonding segment, a bending segment and extending segment. The bonding segment is bonded to the touch module. The bending segment is located between the bonding segment and the extending segment. The bending segment has a bending line, and the bending segment is bended along the bending line.