Abstract: An LED lamp having an operating voltage range within which if the supply voltage is provided within the operating voltage range, the LED lamp produces light in a designed light range, and which has reduced sensitization to ripples. The LED lamp includes a network of passive elements that are structured such that the I-V characteristic curve has a plateau region within the operating voltage range. For instance, a maximum slope of an I-V characteristic curve of the network is shallower within the operating voltage range than the maximum slope of an I-V characteristic curve of the network below the operating voltage range.

Abstract: This patent discloses designs of a controller for a solar powered LED lamp system. The control unit includes a controller that has a switching network and that selectively charges a battery from a solar panel, and selectively discharges the battery to power a lamp. The lamp itself includes a second part of the control unit that prevents over-charge and under-charge conditions of the battery. This may be accomplished using a low power passive network of LEDs and resistors, leaving the controller itself to only perform switching. Thus, the power consumed by the controller, and by the LED lamp system as a whole, may be significantly reduced.

Abstract: A device is designed for channeling electricity to a lamp, and adjusts downwards the amount of power channeled to the lamp as a function of available electrical energy in the source. In so doing, a reduction in the available energy in the source causes a less proportionate reduction in luminosity of the lamp. This might be accomplished by passing the electricity through a passive network of resistors and diodes on its way down to the lamp. In one example, the electrical energy source may be a battery that is powered by one or more solar panels. In that case, the device may also perform the function of protecting the battery from being overly charged. It channels downwards a greater daily lamp's energy consumption than that of daily electrical charging from the solar panels, when the available battery energy is near its full capacity.

Abstract: In an aspect, in general, a lighting fixture includes a plurality of light sources, each light source including an array of light emitting diodes and a reflective surface. The reflective surface of each of the light sources is configured to reflect at least a portion of near field light produced by the other light sources into the far field.

Abstract: A device is designed for channeling electricity to a lamp, and adjusts downwards the amount of power channeled to the lamp as a function of available electrical energy in the source. In so doing, a reduction in the available energy in the source causes a less proportionate reduction in luminosity of the lamp. This might be accomplished by passing the electricity through a passive network of resistors and diodes on its way down to the lamp. In one example, the electrical energy source may be a battery that is powered by one or more solar panels. In that case, the device may also perform the function of protecting the battery from being overly charged. It channels downwards a greater daily lamp's energy consumption than that of daily electrical charging from the solar panels, when the available battery energy is near its full capacity.

Abstract: An energy efficient illumination device is provided in which energy consumption is reduced by using a pulse generating circuit which provides power to LEDs in short pulses, and in which the circuit has a lifespan which is comparable to that of an LED. The illumination device includes a pulse generator circuit employing only passive circuit components and which is used to generate a desired pulsed and positively DC biased output waveform. The pulse generator circuit receives alternating current power as an input, alters the power waveform, and supplies the power to LEDs for a very short time (0.2-15 ms) during each cycle of a 50-60 Hz input signal. This paradigm of pulsed light emission provides ambient lighting that is perceived by humans to be steady and continuous, and which also provides substantial energy savings since power is used in only a fraction of the power cycle.

Abstract: A memory device includes a plurality of memory cells each including a recordable layer between two metal layers, the recordable layer including a first sub-cell and a second sub-cell. Each memory cell is constructed and designed to change from an as-deposited state to an initialized state upon application of an initialization signal, from the initialized state to a first inscribed state upon application of a first write signal, and from the initialized state to a second inscribed state upon application of a second write signal. The memory cell has a resistor-like current-voltage (I-V) characteristic when in the as-deposited state, a diode-like I-V characteristic when in the initialized state, and resistor-like I-V characteristics when in the first and second inscribed states for voltages within a predetermined range.

Abstract: A heat exchange structure includes elongated air ducts. Each air duct has a first opening and a second opening at two ends of the air duct to allow air to enter and exit the air duct, respectively. The heat exchange structure includes an exterior heat exchange surface and interior heat exchange surfaces, in which the exterior heat exchange surface is configured to receive thermal energy from heat generators that are mounted on the exterior heat exchange surface, and the exterior heat exchange surface dissipates a portion of the thermal energy received from the heat generators and transfers another portion of the thermal energy to the interior heat exchange surfaces. The interior heat exchange surfaces are in the elongated air ducts and configured to exchange thermal energy with air flowing in the air ducts, enhancing air flow in the air ducts by buoyancy of heated air.

Abstract: A memory cell of a memory device is fabricated by forming a first electrode on a substrate, positioning a photo mask at a first position relative to the substrate, and forming a first material layer on the first electrode based on a pattern on the photo mask. The photo mask is positioned at a second position relative to the substrate, and a second material layer is formed above the first material layer based on the pattern on the photo mask, the second material layer being offset from the first material layer so that a first sub-cell of the memory cell includes the first material layer and not the second material layer, and a second sub-cell of the memory cell includes both the first and second material layers. A second electrode is formed above the first and second material layers.

Abstract: A memory device includes memory cells each having a recordable layer between two metal layers, each memory cell being constructed and designed to change from a first state to a second state upon application of an initialization signal, and change from the second state to a third state upon application of a write signal. For a voltage within a specified range that is applied across the two metal layers, the memory cell has a lower resistance in the first state than in the second state, and has a higher resistance in the second state than in the third state.

Abstract: A heat exchange structure includes a plurality of elongated air ducts. The heat exchange structure has an exterior heat exchange surface and interior heat exchange surfaces, the interior surfaces being in the elongated air ducts. The heat exchange structure includes a plurality of heat generators that are distributed on the exterior heat exchange surface along an elongated direction of the air ducts, in which air flowing in the air duct is heated successively by heat from the heat generators, and air flow in the air duct is enhanced by buoyancy of heated air.

Abstract: An energy efficient illumination device is provided in which energy consumption is reduced by using a pulse generating circuit which provides power to LEDs in short pulses, and in which the circuit has a lifespan which is comparable to that of an LED. The illumination device includes a pulse generator circuit employing only passive circuit components and which is used to generate a desired pulsed and positively DC biased output waveform. The pulse generator circuit receives alternating current power as an input, alters the power waveform, and supplies the power to LEDs for a very short time (0.2-15 ms) during each cycle of a 50-60 Hz input signal. This paradigm of pulsed light emission provides ambient lighting that is perceived by humans to be steady and continuous, and which also provides substantial energy savings since power is used in only a fraction of the power cycle.

Abstract: A light emitting device firstly includes a light emitting diode (LED) structure, having a top surface with a light emitting region. The device also has a heterojunction within the device structure, the heterojunction having a p-type and an n-type semiconductor layer, and a plurality of electrodes positioned on the top surface, each being electrically connected to one of the p-type and n-type semiconductor layers. At least a first and a second electrodes are connected to a same type semiconductor layer and are physically separated from each other. The device further includes a first and a second heterojunction regions within the heterojunction, each being respectively defined between one of the first and second electrodes and one of the other electrodes connected to the other type semiconductor layer. The first and second heterojunction regions are alternatively driven for emitting lights in the time domain.

Abstract: A light emitting device includes a first light emitting diode (LED) emitting a first light emission of at least a first wavelength, and a second light emitting diode emitting a second light emission of at least a second wavelength. The second LED is placed in close proximity to the first LED such that after a mixing length from the first and second LEDs, a combination of the first and second lights is perceived as one color in the human vision. In use, the first and second LEDs are alternately driven by a power source in the time domain.

Abstract: A heat exchange structure includes elongated air ducts. Each air duct has a first opening and a second opening at two ends of the air duct to allow air to enter and exit the air duct, respectively. The heat exchange structure includes an exterior heat exchange surface and interior heat exchange surfaces, in which the exterior heat exchange surface is configured to receive thermal energy from heat generators that are mounted on the exterior heat exchange surface, and the exterior heat exchange surface dissipates a portion of the thermal energy received from the heat generators and transfers another portion of the thermal energy to the interior heat exchange surfaces. The interior heat exchange surfaces are in the elongated air ducts and configured to exchange thermal energy with air flowing in the air ducts, enhancing air flow in the air ducts by buoyancy of heated air.

Abstract: A ceramic composition including a first ceramic material and a second ceramic material that is in the form of nano-, submicron-, or micron-sized particles, in which the first ceramic material has a lower melting point than the second ceramic material, and, when the first ceramic material melts into a liquid and the second ceramic material remains particulate, the second ceramic material floats at the top of the liquid. Also disclosed is a variant of this composition including a first ceramic material and a second ceramic material, in which the second ceramic material has a melting point higher than the first ceramic material, and, when the first ceramic material melts into a liquid, the second ceramic material partially or completely dissolves in the liquid.

Abstract: A heat exchange structure includes elongated air ducts. Each air duct has a first opening and a second opening at two ends of the air duct to allow air to enter and exit the air duct, respectively. The heat exchange structure includes an exterior heat exchange surface and interior heat exchange surfaces, in which the exterior heat exchange surface is configured to receive thermal energy from heat generators that are mounted on the exterior heat exchange surface, and the exterior heat exchange surface dissipates a portion of the thermal energy received from the heat generators and transfers another portion of the thermal energy to the interior heat exchange surfaces. The interior heat exchange surfaces are in the elongated air ducts and configured to exchange thermal energy with air flowing in the air ducts, enhancing air flow in the air ducts by buoyancy of heated air.

Abstract: A light source includes a plurality of lighting elements arranged to illuminate different regions of visual perception. Circuitry coupled to the light source is configured to supply power to a first subset of the lighting elements according to a first waveform and to a second subset of the lighting elements according to a second waveform out of phase with the first waveform.

Abstract: A heat exchange structure includes a plurality of elongated air ducts. The heat exchange structure has an exterior heat exchange surface and interior heat exchange surfaces, the interior surfaces being in the elongated air ducts. The heat exchange structure includes a plurality of heat generators that are distributed on the exterior heat exchange surface along an elongated direction of the air ducts, in which air flowing in the air duct is heated successively by heat from the heat generators, and air flow in the air duct is enhanced by buoyancy of heated air.

Abstract: A heat exchange structure includes elongated air ducts. Each air duct has a first opening and a second opening at two ends of the air duct to allow air to enter and exit the air duct, respectively. The heat exchange structure includes an exterior heat exchange surface and interior heat exchange surfaces, in which the exterior heat exchange surface is configured to receive thermal energy from heat generators that are mounted on the exterior heat exchange surface, and the exterior heat exchange surface dissipates a portion of the thermal energy received from the heat generators and transfers another portion of the thermal energy to the interior heat exchange surfaces. The interior heat exchange surfaces are in the elongated air ducts and configured to exchange thermal energy with air flowing in the air ducts, enhancing air flow in the air ducts by buoyancy of heated air.