Abstract: An apparatus includes a substrate having a surface, and a transparent semiconductor photocatalyst layer secured to the surface of the substrate, wherein the photocatalyst layer includes titanium oxide and a component selected from a fluorescent dye, ultra-fine glitter, indium tin oxide, aluminum zinc oxide, silver nitrate, and combinations thereof. The photocatalyst coating may be formed on a substrate using a formulation that includes an aqueous mixture of titanium oxide and amorphous titanium peroxide, wherein the aqueous mixture may further include one of the components. A method of forming the photocatalyst coating may include applying an aqueous mixture of titanium oxide and amorphous titanium peroxide to a surface of the substrate, wherein the photocatalyst coating includes a fluorescent dye, ultra-fine glitter, indium tin oxide, aluminum zinc oxide, and/or silver nitrate. The aqueous mixture may then be dried and heated to 100 degrees Celsius or greater.

Abstract: A power converter and method for providing surge protection to the power converter is provided herein. An over voltage protection portion of a protection circuit is coupled between the rail voltage and ground reference of the power converter, and senses a first magnitude of the rail voltage. An under voltage protection portion of the protection circuit is coupled to a controller of the power converter and further between the rail voltage and the ground reference, and senses a second magnitude of the rail voltage to be transmitted to the controller. A regulator block is coupled between the over voltage protection portion and the under voltage protection portion, and is configured to compare the first magnitude of the rail voltage to a reference voltage of the regulator block, and to short circuit the under voltage protection portion when the first magnitude of the rail voltage is greater than the reference voltage.

Abstract: An edge mount magnetic component includes a bobbin and two E-core halves. The bobbin is configured to receive the two E-core halves when body portions of the two E-core halves are positioned vertically. The bobbin includes a first outer flange, a second outer flange, and a passageway spanning therebetween. The bobbin further includes first, second, third, and fourth pin supports. The first and second pin supports are connected to an outer surface of the first end flange and are spaced apart by at least a width of the passageway. The third and fourth pin supports are connected to an outer surface of the second end flange and are spaced apart by at least the width of the passageway. The bobbin further includes slots for routing a winding to a pin and includes walls to ensure the winding is electrically separated from the E-core halves.

Abstract: A binocular scanning laser ophthalmoscope (SLO) is used to track the fixational eye movement of each of the eyes of a subject. The binocular SLO may include right eye optics for imaging a portion of the retina of the right eye and left eye optics for imaging a portion of the retina of the left eye. Shifts in the imaged portion of the retina with respect to a reference image of the retina may be used to measure and track eye movement. The right eye optics and left eye optics may be separate imaging paths, each with its own bi-directional MEMS scanning mirror and Keplerian telescope. The use of the MEMS scanning mirrors minimizes the size and weight of the binocular SLO.

Abstract: A resonant power converter is disclosed with a method of limiting output current therefrom. A switch operating frequency is regulated to provide output current to a load, wherein an error signal corresponds to a difference between the output current and a reference value. The error value is fed back to switch operating frequency control circuit via an optocoupler. A maximum detector diode current for the optocoupler is clamped to a maximum value when the error signal exceeds or equals a clamping threshold value. The clamping threshold value may correspond to a maximum output current at a maximum normal operating temperature, wherein the method utilizes the relationship between ambient temperature and the current transfer ratio (CTR) for the optocoupler. The CTR decreases when the detector diode current is clamped, which decreases output current and output power, reducing power loss in the enclosure and relieving thermal stress at high temperatures.

Abstract: An end cap mounting system for a lens of a lighting fixture includes a lens engagement portion having a proximal end, a distal end, an outer surface and an inner surface. The inner surface defines a cavity extending distally into the lens engagement portion from the proximal end for a cavity depth to a cavity end surface. The cavity has an inner wall with a perimeter corresponding to a first asymmetric shape of an outer profile of a lens. A central protrusion extends proximally from the cavity end surface towards the proximal end. The protrusion has an outer wall with a perimeter that corresponds to a second asymmetric shape of an inner profile of the lens. A gasket-receiving recess is positioned proximate to the cavity end surface between the outer wall of the central protrusion and the inner wall of the cavity to receive a gasket.

Abstract: Multi-driver configuration apparatuses, systems, and methods are provided. Apparatuses, systems, and methods are provided for multi-driver configuration of a plurality of light emitting diode (LED) drivers. The system includes a plurality of LED drivers having a transformer, an input interface coupleable to the configuration device via a common communication medium, a microcontroller, a direct current (DC) sensing section to detect at least a portion of a tuning signal received at the input interface and to transmit a driver control input signal corresponding to the at least a portion of the tuning signal to the microcontroller, and a transmit switch configured to receive a driver control output signal from the microcontroller and to cause at least one output signal to be output from the LED driver via the input interface. A configuration device transmits the tuning signal to at least one LED driver.

Abstract: An LED driver includes a temperature sensing circuit integrated within its housing. The sensing circuit generates signals corresponding to actual temperature values within the driver housing to a controller. The controller receives programmable temperature derating parameters at least partially related to a light fixture receiving the driver housing, converts the temperature sensor signal into the actual temperature value, and derates the output current in linear fashion according to a transfer function when the actual temperature value falls within the temperature derating parameters. The parameters may include starting and ending temperatures, and an ending current parameter. The temperature sensing circuit may include a voltage divider with a negative thermal coefficient (NTC) device, preferably as the high side resistor.

Abstract: An LED driver circuit includes a DC-to-AC inverter that provides a primary AC voltage to the input node of a resonant tank circuit. The resonant tank circuit includes a resonant tank circuit inductor, a resonant tank circuit capacitor and a primary winding of an output transformer. The resonant tank circuit capacitor and the primary winding are connected in parallel between a resonant tank circuit output node and a DC balance node. The DC balance node is coupled to a first bus by a first DC-blocking capacitor and is coupled to a second bus by a second DC-blocking capacitor. The output transformer has at least one secondary winding. An AC output voltage from the secondary winding is rectified to generate a DC voltage, which is applied to a load having a plurality of LEDs. The resonant tank circuit input node is clamped by first and second clamping diodes.

Abstract: A magnetic connector assembly has two independent magnetic components sharing a common core structure. The magnetic assembly includes first and second bobbins, and includes a magnetic core. The first bobbin is positioned perpendicularly to the second bobbin. The magnetic core includes at least two core pieces. In an exemplary embodiment, the magnetic core includes first, second, and third core pieces. The first core piece includes at least a first primary middle leg configured to fit within a passageway of the first bobbin and a first auxiliary middle leg configured to fit within a passageway of the second bobbin. The second core piece includes at least a second primary middle leg configured to fit within the passageway of the first bobbin. The third core piece includes a second auxiliary middle leg configured to fit within the passageway of the second bobbin. The auxiliary legs are perpendicular to the primary legs.

Abstract: Circuitry and methods are provided for dynamically controlling the operating frequency of a resonant power converter. A feedback circuit generates error signals representing a difference between sensed output voltages and a constant target output voltage. A controller comprises a frequency control input terminal, and generates drive signals to half-bridge switching elements at determined operating frequencies. A frequency control circuit is coupled between the feedback circuit and the frequency control input terminal. The frequency control circuit sets minimum and maximum operating frequencies for the controller, and dynamically adjusts the operating frequency with respect to the constant target output voltage. A frequency control power supply circuit may further provide signals to the frequency control circuit representative of voltage across the resonant capacitor, wherein the minimum operating frequency is dependent thereon.

Abstract: A magnetic connector assembly has two independent magnetic components sharing a common core structure. The magnetic assembly includes first and second bobbins, and includes a magnetic core. The magnetic core includes first and second core halves, each half including a main core body, a first outer leg, a second outer leg, and a middle leg. The first outer leg fits within a passageway of the first bobbin. The second outer leg fits within a passageway of the second bobbin. The middle leg fits between the two bobbins.

Abstract: A light stack having an elongate body having a length extending from a proximal end to a distal end of the elongate body. A plurality of light emitting diode (LED) arrays adjustably coupled with the elongate body and arranged along the length thereof and a control module coupled with the plurality of LED arrays, wherein the each of the plurality of LED arrays is operable to pivot, thereby forming an angle relative to the elongate body. The control module configured to individually transition each of the plurality of LED arrays between a light emitting condition and a non-light emitting condition. The plurality of LED arrays configured to be adjustable to pivot on an axis at an angle relative to the elongate body.

Abstract: A resonant power converter as disclosed herein, e.g., an LED driver, comprises first and second switches in a half-bridge arrangement and responsive at an operating frequency to controlled drive signals. A resonant circuit is coupled between the switch output and an isolation transformer. A negative feedback control loop provides an error signal for regulation of the output current. A reference control circuit is added to the feedback control loop, and configured to sense when the error signal exceeds a threshold value, and further configured in response to control a feedback reference signal wherein the error signal is reset to a value below the threshold value. By resetting the feedback control reference value, loop runaway may be prevented, e.g., for enough time that the LED load may warm up or otherwise stabilize. As a result the LED driver will always maintain negative current closed loop control, and restore normal operating mode.

Abstract: A magnetic assembly structure includes a bobbin, an outer core, an inner core, and a gap spacer. The bobbin has first and second flanges. The bobbin has a passageway extending between the first and second flanges. The passageway has at least one crushable passageway rib and a channel wall parallel to the second flange. The outer core is positioned around the first and second flanges. The outer core includes an opening positioned near the first flange. The inner core is positioned in the opening and in the passageway. The gap spacer is positioned between the inner core and an inner surface of the outer core. The gap spacer and outer core are held in frictional engagement between the inner core and channel wall. The gap spacer defines a gap distance which is adjustable by replacing the gap spacer with one of having a different thickness. Adjusting the gap distance modifies the inductance.

Abstract: A light-emitting diode (LED) driver circuit includes a DC-to-AC inverter that provides a primary AC voltage to the primary winding of an output transformer via a resonant tank circuit. The transformer has at least one secondary winding. An AC output voltage from the secondary winding is rectified to generate a DC voltage, which is applied to a load having a plurality of LEDs. An overshoot control circuit electrically connected in parallel with the primary winding of the transformer prevents the DC voltage applied to the load from exceeding the forward bias of the LEDs during startup conditions until the resonant tank circuit is stabilized. The overshoot control circuit includes a first diode and a first capacitor and further includes a second diode and a second capacitor. The first and second capacitors absorb energy during alternate half cycles of the primary AC voltage until the resonant tank circuit is stabilized.

Abstract: A resonant power converter (e.g., LED driver) comprises a switching power stage having an operating frequency to produce output current through an LED load. A current sensor is coupled to the LED load, and a negative control means regulates the operating frequency based on error signals from the sensed current relative to a reference value. A reference control circuit controls the error signal (e.g., by manipulating the reference value) responsive to the error signal exceeding a reference error signal for regaining negative feedback control. The reference control circuit includes a quick discharge circuit for quickly reducing the error signal when it exceeds the reference error signal, and a slow charge circuit for slowly increasing the error signal when it is reduced, for example giving the LED load time to warm up in transition from a cold operational state to a normal operational state.

Abstract: A magnetic connector assembly has three independent magnetic components sharing a common core structure. The magnetic assembly includes first, second, and third bobbins, and includes a magnetic core. The first bobbin includes at least one latch mechanism of a first type. The second bobbin includes at least one latch mechanism of the first type. The third bobbin includes at least one latch mechanism of a second type configured to engage the latch mechanisms of the first and second bobbins. The magnetic core includes first and second core halves, each including a main core body, a first outer leg, a second outer leg, a middle leg, a first intermediate leg, and a second intermediate leg. The first outer leg fits within a passageway of the first bobbin. The second outer leg fits within a passageway of the second bobbin. The middle leg fits within a passageway of the third bobbin.

Abstract: A low profile inductive apparatus is provided via one or more traces in a printed circuit board, the one or more traces defining inductive winding turns about an aperture, and a core comprising an elongate core member configured for positioning through the aperture of the circuit board. The core may be press fit with respect to the printed circuit board, or alternatively the elongate core member and the aperture may be reciprocally threaded. In an embodiment, core flanges may be provided on opposing sides of the printed circuit board, with the elongate core member connected between the core flanges and extending through the aperture. The number of inductive winding turns relates to a required inductance of the inductor when the elongate core member is positioned through the aperture, and a width and thickness of the windings corresponds to a required carrying capacity of the inductor.

Abstract: A tunable magnetic assembly includes a bobbin, an outer core, and an inner core. The bobbin has a first and second flanges. The bobbin has a passageway extending between the first and second flange. The passageway has a spiral track defined in a passageway surface. The outer core is positioned around the first and second flanges. The outer core includes an opening positioned near the first flange. The inner core is positioned in the opening and in the cylindrical passageway. The inner core includes at least one protrusion extending from an outer surface and configured to engage the spiral track. A gap distance is defined between the inner core and a portion of the outer core near the second flange. The gap distance is adjustable by moving the protrusion within the spiral track. Adjusting the gap distance modifies the inductance.