摘要:
A spare receiver in a CMTS is used to non-invasively test the upstream signal quality of a network without disrupting a subscriber's operations. A modem registered with a receiver on the network is selected as a testing modem. The spare receiver is RF connected to the receiver and the testing modem is tuned to the spare receiver. The testing modem is used to test the signal quality of the network, such as by using a SNR test. The testing modem remains registered with the network during the testing operation. Other modems are prevented from registering with the spare receiver. If other modems attempt to register on the spare receiver, the system overrides their attempts and moves them back to another receiver. The testing modem is returned to its original receiver when testing is completed.
摘要:
A spare receiver in a CMTS is used to non-invasively test the signal quality of an original channel frequency of a receiver which has been tuned to another channel frequency so the operator can retune the receiver to its original channel frequency without disrupting subscriber operations. The spare receiver is RF connected to the receiver and performs RSSI testing on the channel frequency. If the channel frequency is sufficiently noise free, a modem is registered on the spare receiver as a testing modem. The testing modem is used to test the signal quality of the network, such as by using a SNR test. When the original channel frequency is determined to have a sufficient SNR value, the receiver is retuned to its original channel frequency.
摘要:
A light emitting diode (LED) grown on a substrate doped with one or more rare earth or transition element. The dopant ions absorb some or all of the light from the LED's active layer, pumping the electrons on the dopant ion to a higher energy state. The electrons are naturally drawn to their equilibrium state and they emit light at a wavelength that depends on the type of dopant ion. The invention is particularly applicable to nitride based LEDs emitting UV light and grown on a sapphire substrate doped with chromium. The chromium ions absorb the UV light, exciting the electrons on ions to a higher energy state. When they return to their equilibrium state they emit red light and some of the red light will emit from the LED's surface. The LED can also have active layers that emit green and blue and UV light, such that the LED emits green, blue, red light and UV light which combines to create white light. Alternatively, it can have one active layer and grown on a sapphire substrate doped with Cr, Ti, and Co such that the substrate absorbs the UV light and emits blue, green, and red light. The invention is also capable of providing a tunable LED over a variety of color shades. The invention is also applicable to solid state laser having one or more active layers emitting UV light with the laser grown on a sapphire substrate doped with one or more rare earth or transition elements.
摘要:
A physically robust light emitting diode is disclosed that offers high-reliability in standard packaging and that will withstand high temperature and high humidity conditions. The diode comprises a Group III nitride heterojunction diode with a p-type Group III nitride contact layer, an ohmic contact to the p-type contact layer, and a sputter-deposited silicon nitride composition passivation layer on the ohmic contact. A method of manufacturing a light emitting diode and an LED lamp incorporating the diode are also disclosed.
摘要:
An LED with improved current spreading structures that provide enhanced current injection into the LED's active layer, improving its power and luminous flux. The current spreading structures can be used in LEDs larger than conventional LEDs while maintaining the enhanced current injection. The invention is particularly applicable to LEDs having insulating substrates but can also reduce the series resistance of LEDs having conductive substrates. The improved structures comprise conductive fingers that form cooperating conductive paths that ensure that current spreads from the p-type and n-type contacts into the fingers and uniformly spreads though the oppositely doped layers. The current then spreads to the active layer to uniformly inject electrons and holes throughout the active layer, which recombine to emit light.
摘要:
A physically robust light emitting diode is disclosed that offers high-reliability in standard packaging and that will withstand high temperature and high humidity condition. The diode comprises a Group III nitride heterojunction diode with a p-type Group III nitride contract layer, an ohmic contact to the p-type contact layer, and a sputter-deposited silicon nitride composition passivation layer on the ohmic contact. A method of manufacturing a light emitting diode and an LED lamp incorporating the diode are also disclosed.
摘要:
Naturally occurring polarization-induced electric fields in a semiconductor light emitter with crystal layers grown along a polar direction are reduced, canceled or reversed to improve the emitter's operating efficiency and carrier confinement. This is accomplished by reducing differences in the material compositions of adjacent crystal layers, grading one or more layers to generate space charges and quasi-fields that oppose polarization-induced charges, incorporating various impurities into the semiconductor that ionize into a charge state opposite to the polarization induced charges, inverting the sequence of charged atomic layers, inverting the growth sequence of n- and p-type layers in the device, employing a multilayer emission system instead of a uniform active region and/or changing the in-plane lattice constant of the material.
摘要:
A light emitting diode (LED) grown on a substrate doped with one or more rare earth or transition elements. The dopant ions absorb some or all of the light from the LED's active layer, pumping the dopant ion electrons to a higher energy state. The electrons are naturally drawn to their equilibrium state and they emit light at a wavelength that depends on the type of dopant ion. The invention is particularly applicable to nitride based LEDs emitting UV light and grown on a sapphire substrate doped with chromium. The chromium ions absorb the UV light, exciting the electrons on ions to a higher energy state. When they return to their equilibrium state they emit red light and some of the red light will emit from the LED's surface. The LED can also have active layers that emit green, blue and UV light, such that the LED emits green, blue, red and UV light which combines to create white light. Alternatively, it can have one active layer and grown on a sapphire substrate doped with Cr, Ti, and Co such that the substrate absorbs the UV light and emits blue, green, and red light. The invention is also capable of providing a tunable LED over a variety of color shades. The invention is also applicable to solid state lasers having one or more active layers emitting UV light with the laser grown on a sapphire substrate doped with one or more rare earth of transition elements.
摘要:
A light emitting diode includes a diode region having a gallium nitride based n-type layer, an active region and a gallium nitride based p-type layer. A first reflector layer is provided on the gallium nitride based p-type layer, and a second reflector layer is provided on the gallium nitride based n-type layer. Bonding layers, a mounting support, a wire bond and/or transparent oxide layers also may be provided.
摘要:
Light emitting diodes include a substrate having first and second opposing faces and that is transparent to optical radiation in a predetermined wavelength range and that is patterned to define, in cross-section, a plurality of pedestals that extend into the substrate from the first face towards the second face. A diode region on the second face is configured to emit light in the predetermined wavelength range, into the substrate upon application of voltage across the diode region. A mounting support on the diode region, opposite the substrate is configured to support the diode region, such that the light that is emitted from the diode region into the substrate, is emitted from the first face upon application of voltage across the diode region. A reflector is provided between the mounting support and the diode region, that is configured to reflect light that is emitted from the diode region back into the diode region, through the substrate that is transparent to optical radiation in the predetermined wavelength range and from the plurality of pedestals, upon application of voltage across the diode region. A layer of Indium Tin Oxide (ITO) is provided between the reflector and the diode region.