Abstract: The present invention relates to a clip type light emitter, and in particular to a clip type light emitter capable of enhancing a visual field at night by detachably engaging a clip type light emitter to a leisure cap (including hat) generally used for a mountain climbing or fishing or travel or various sports. The clip type light emitter comprises a casing forming a body; a plurality of lamps provided at a front side of the casing at regular intervals; a switch part provided in one side of the casing; a battery provided in the interior of the casing; and a clip provided in an upper side of the casing and having one side end integrally engaged with the casing and having a certain elastic force, wherein the clip type light emitter is detachably engaged to a leisure cap (including hat) used for a mounting climbing, a fishing or various outdoor leisure and sports.

Abstract: A versatile, low profile, lightweight, compact, body mounted lighting system includes a housing mountable to a person's body and a light module in the housing. The light module may include at least one LED producing a beam. There is a lens in front of the LED and a mechanism is configured to move the lens to adjust the distance between the lens and the LED to vary the size of the beam.

Abstract: A glass breaking cap for flashlights, batons and the like is provided. The glass breaking cap has a cylindrical sidewall and a conical top portion. The conical top portion has an apex having an included angle between 86° and 136°. More preferably, the apex has an included angle of 106° to 126° with a preferred included angle of about 116°. Preferably, the glass breaking cap has male or female threads for replacing threaded end caps found on traditional flashlights and batons.

Abstract: A lamp module includes: a single piece of a mounting base including an arcuate mounting plate defining two retaining recesses, and a bracket extending upwardly from the mounting plate; two socket units mounted respectively on two opposite ends of the bracket, each of the socket units being formed with pin holes adapted to receive pins of a fluorescent tube; an arcuate reflective plate having two opposite lower ends received in the retaining recesses in the mounting plate; and a pair of connectors provided on the sockets units and having pins for insertion into pin holes in sockets of a ceiling lamp suspending holder.

Abstract: Provided is a backlight assembly which includes integral power supply sockets and ground sockets, in which the number of parts is reduced in addition to the manufacturing cost. The backlight assembly includes a lamp including a lamp tube and an electrode that protrudes beyond either end of the lamp tube, a power supply socket including a first plate that has a first guide groove through which the electrode is inserted and a plate spring that is disposed on one side of the first plate and fixes the electrode in the first guide groove by pressurizing the electrode, and a bottom chassis containing the lamp and the power supply socket therein, in which the first plate and the plate spring are formed of a conductive material.

Abstract: An interior lamp can achieve both an excellent illumination function and an excellent illumination effect (providing a comfortable environment) and may possibly provide high merchandizability characteristics. The interior lamp can include an LED light source unit having a substrate and a plurality of white LED lamps and colored LED lamps mounted on the substrate. A cover case can be provided to serve as a light illumination unit. The light illumination unit can include a double-layer structure having a light diffusion layer and a light transmission layer. The light diffusion layer can have a plurality of penetrating holes. The light transmission layer can have a plurality of convex lens portions. The center axes of the penetrating holes and the corresponding lens portions can coincide with corresponding optical axes of the white LED lamps, respectively.

Abstract: Provided are a light emitting apparatus and a surface light source apparatus having the same. The light emitting apparatus comprises a package body, a first color light emitting part in a first cavity of the package body, and a second color light emitting part in a second cavity of the package body. The package body comprises a plurality of cavities.

Abstract: A seven-color light emitting module and a seven-color decorating lamp string comprising the same. The seven-color light emitting module includes a lampshade made of a transparent plastic or synthetic resin, and a lamp socket on which three colors self-flashing light emitting diode, a zener diode, a current limiting resistance and a double-side printed circuit board (PCB) are sealed. The three colors light emitting diodes connect with PCB and connect with the zener diode in parallel. One end of the zener diode or two ends of the zener diode connects with the current limiting resistance in series. A transparent epoxy resin or silicon glue is filled in the lampshade.

Abstract: An athletic field lighting system, wherein fixtures are provided in clusters. Each cluster can be turned, on and set to a nominal output level. Thereafter, individual fixture output intensity levels are adjusted by means of feedback loops containing a photosensor mounted in the back of the reflector of each fixture and a pole-mounted logic center which compares commanded and actual output intensities and produces an error signal capable of producing small increments of adjustment by way of dimmer packs associated with individual fixtures. A short, range radio link is provided between an athletic field command center and each of the individual pole-mounted logic systems. A remote link between, a remote control center and the field located control center may be provided as desired.

Abstract: Two light sources 33A and 33B are disposed on a light entrance surface side of a light guiding plate 32. Deflection pattern elements 53A and 53B are disposed concentrically around a middle point Q between the light sources 33A and 33B. One deflection pattern element 53A is disposed in such a fashion that, in plan view, a direction of a normal to a light reflection surface thereof is parallel to a direction connecting the deflection pattern element 53A and the corresponding light source 33A. Also, the other deflection pattern element 53B is disposed in such a fashion that, in plan view, a direction of a normal to a light reflection surface thereof is parallel to a direction connecting the deflection pattern element 53B and the corresponding light source 33B. With such constitution, brightness of a surface light source device is improved.

Abstract: A manufacture method of a light emitting device is provided. Firstly, at least one circuit board is provided. A plurality of light emitting packages, a first undetermined power input end and a second undetermined power input end are disposed at the circuit board. The light emitting packages are electrically connected to the first undetermined power input end and the second undetermined power input end. Each of the first undetermined power input end and the second undetermined power input end has at least two first pads. The first pads of each of the first undetermined power input end and the second undetermined power input end are electrically isolated from each other. Next, the first undetermined power input end is selected to be a power input region for inputting an external power signal. Then, the first pads of the second undetermined power input end are electrically connected to each other.

Abstract: A method and/or apparatus is provided for constructing a dichroic color mixing flag for a multiparameter light that greatly improves the thermal shock tolerance of the flag and avoids having to use a more costly quartz substrate material as in the prior art.

Abstract: The invention relates to a reflector for a luminaire. The reflector comprises a cavity (101) for receiving a lamp intended to emit light and, located around said cavity, a first annular louver member (201) arranged in a first direction and a second annular louver member (202) arranged in a second, opposite direction.

Abstract: Illumination systems and related components and methods are disclosed.

Abstract: In an optical circuit including multi-dimensional photonic crystals, in which the optical circuit has a structure (33), such as a light emitting member or a light receiving member, having a natural resonance frequency, another structure (34) having a natural resonance frequency slightly differing from the natural resonance frequency of the structure (33) is arranged in the vicinity of the structure (33) to control the directivity of localization and propagation of an electromagnetic field, light emission and light reception in a spatial region including the above structures in the multi-dimensional photonic crystals, in order to permit functional operations to be realized.

Abstract: Provided are a light unit and a liquid crystal display (LCD) having the same. The light unit comprises a housing; at least one first printed circuit board (PCB) arranged in the housing in a first direction; at least one second PCB arranged in the housing in a direction opposite to the first direction; and light emitting diodes mounted on the first and second PCBs.

Abstract: A light-emitting device including a light source that exhibits polarization anisotropy and a reflector that is shaped so that for light emitted in at least two directions from the light source, the angle between the dominant polarization directions after reflecting from the reflector is smaller than the angle between the dominant polarization directions before reflecting from the reflector. In the light-emitting device the light source may be a light-emitting diode chip or one of a plurality of light sources.

Abstract: The clarifying filter is a visual enhancement device in which Liquids, Plasmas, Crystals, or other transparent, translucent, or other non-opaque materials are sandwiched between supporting layers to provide the diffusion provided by such materials to enhance the light provided by a light source.

Abstract: An illumination device comprising an LED (14) mounted on a rear of a PCB (12), and a light pipe (16) to direct light from the LED through an aperture (18) in the PCB to illuminate a legend (10) on the front of the PCB, the light pipe diffusing the light so as to prevent uneven illumination of the legend.

Abstract: A diffuser-reflector assembly for use with a photographic flash lamp (800) comprises, in one aspect, an elastic base (100) having rigid first inserts (125 and 130), two arms (105 and 110), a shaft (135), a pivot assembly (150), and one or more frames (116, 121) that hold second inserts (115, 120). The diffuser-reflector assembly installs slidably onto the light-emitting end of a flash lamp (800). The second inserts can have various optical properties. They can be specular or diffuse reflectors, color or neutral density filters, or a combination. The frames and inserts can be swung on the arms and independently pivoted over a wide range of angles above the lamp, thereby providing a wide range of lighting effects. The frames and arms are held in place by friction and can be adjusted by manual force. The entire assembly can be made of simple parts that snap together.

Abstract: An LED lamp includes a lamp base, a heat sink and a plurality of LED modules. The lamp base includes a lamp holder and an enclosure connecting with the lamp holder. The enclosure defines a plurality of vents therein. The heat sink is mounted on the lamp base and includes a cylinder at a centre thereof and a plurality of fins surrounding the cylinder. The cylinder has a through hole therein, which communicates with the enclosure. The through hole, the enclosure and the vents cooperatively form an air circulation passage communicating with ambient air. The LED modules are mounted on outmost ones of the fins of the heat sink, respectively.

Abstract: The present invention provides a lamp structure that overcomes the shortcomings of a typical lamp with a fixed radiation angle and single support or main pedestal. The lamp includes a main pedestal and a support. The main pedestal has an assembly portion. A positioning member is used to control the positioning or released state of the assembly portion, so that the support could be adjusted to allow for flexible rotation of the radiation angle of the light-emitting body if the flexible locking bead and locating hole are positioned securely. The support could be removed from or assembled into different types of main pedestals through the recessed pattern of holes set on the main pedestal. Thus, a single support could be applied to a variety of main pedestals for improved application of lamps.

Abstract: The disclosed subject matter can include a vehicle lamp having a favorable light distribution and an effective heat dissipation structure. The vehicle lamp can include a light source and a casing in which the light source is sealed. The casing can be configured in a tubular shape and a reflector can be configured in a hollow of the casing. The casing can be sealed between the reflector and a front lens configured to allow light emitted from the light source to pass therethrough. The inner surfaces of the casing and the reflector can be configured to form a predetermined light distribution via the front lens. The outer surfaces of the casing and the reflector can be exposed to the outside and can be configured to radiate heat generated from the light source to the outside using heat conductive material. Thus, the lamp can be miniaturized and provide favorable light distribution.

Abstract: A light-emitting diode module is mounted on an instrument panel of an automotive vehicle for illuminating a scale plate of the instrument panel. The module is composed of a light-emitting diode and a holder for supporting the diode thereon. The holder includes a housing made of molded resin and conductor plates embedded in the housing. The light-emitting diode is mounted in a depressed portion formed in the housing, and the holder is mounted on a circuit board to supply electric power to the light-emitting diode through the conductor plates embedded in the housing. A front surface of the housing and a front surface of the light-emitting diode are made flush with each other so that a flat surface made by both front surfaces is positioned close to a rear surface of the scale plate. Light emitted from the module is efficiently utilized for illuminating the scale plate by positioning the module at a right position with respect to the light-conducting plate.

Abstract: Headlamp systems are provided that form desired beam patterns from light supplied by semiconductor light sources. The present invention is headlamp system for a vehicle including at least one first light source, at least one second light source, and a first lens system having at least one lens operably associated with the at least one first light source to provide a spread portion of a desired beam pattern. The present invention also includes second lens system having at least one lens operably associated with the at least one second light source to provide a hot spot portion of the desired beam pattern.

Abstract: The invention relates to an LED collimator element (1; 20) which can be used in particular for motor vehicle headlights. It comprises an LED (2; 23), of which the emitted light can be emitted essentially directly into an emission angle region of the LED collimator element (1; 20), and a collimator (3; 22) which deflects the light which is not emitted in the emission direction into the emission angle region. The LED collimator element (1; 20) is designed to be asymmetrical at least with respect to a sectional plane (4) so that a defined non-uniform light intensity distribution is achieved in an emission plane (10; 26) of the LED collimator element (1; 20) which is orthogonal to the sectional plane (4) and to the main emission direction.

Abstract: Some embodiments provide an illumination optical system. The optical system can include a first surface and a second surface. Each of the first and second surfaces can further comprises a multiplicity of corresponding Cartesian-oval lenticulations such that each lenticulation of the first surface focuses a source upon a corresponding lenticulation of the second surface and each lenticulation of the second surface focuses a target upon a corresponding lenticulation of the first surface.

Abstract: A headlight unit having a virtual pivot center provided at a position different from a supported position to a vehicle body. Two, upper and lower headlight supporting portions spaced apart from each other are provided at a rear portion of a headlight unit The upper headlight supporting portion on each side includes a guide shaft formed on a support member of a radiator cover and a groove formed on an upper base portion of the headlight unit. The lower headlight supporting portion on each side includes an elongated hole formed through the support member of the radiator cover and a bolt threadedly engaged with a lower base portion of the headlight unit. The guide shaft and the bolt slide in the groove and the elongated hole, respectively, for performing the swing motion of the headlight unit about the virtual pivot center C to perform an adjustment of an optical axis.

Abstract: A lighting module for a motor vehicle headlight, designed to give a beam with cutoff, and comprising at least one light source, a collecting mirror, a bender having a reflective surface and a cutoff edge, a return mirror, for producing towards the front the output beam with cutoff the surfaces of the collecting mirror, of the bend and of the return mirror being conjugate surfaces such that the collecting mirror converts a spherical wave issuing from the center of the source into a wave surface reducing to a two-dimensional curve, convex towards the front, the cutoff edge of the bender is merged with this curve, the return mirror converts the above wave surface into at least one cylindrical wave surface of vertical axis having as its cross-section a curve.

Abstract: An LED module is described with a base 10 made out of a heat conducting material. An LED element (32) is arranged in a cavity (11) of the base. A collimator reflector (70) is formed by reflective surfaces (24, 64, 66a). Three of these reflective surfaces (66a, 66b, 64) are provided on a plastic insert (60) received in the cavity (11). A further reflective surface (24) is provided on the base (10) itself. This surface (24) has a straight border line (50). The collimator reflector (70) is arranged to reflect light from the LED (32) so that a cut-off (72) is formed by the straight border line (50). By thus integrating the cut-off, as the most critical optical element, into the base (10) itself, high accuracy is achieved.

Abstract: The screwdriver has a handle and a rigid shaft that extends from the handle. The shaft has an end for engaging a screw. It also has a bore that extends from the handle to the screw-engaging end of the shaft. A LED is situated in the bore, proximate the screw-engaging end of the shaft. The handle has a recess. A battery is situated within the recess. The LED is electrically connected to battery by a wire extending through the bore, between the LED and the handle. Interchangeable heads are provided for use with screws of various configurations.

Abstract: A waveguide based on a three-dimensional photonic crystal is arranged to provide wave-guiding in a single mode and a mode having a field strength distribution with unimodality in a plane perpendicular to the wave-guiding direction, to thereby enable wave-guiding in a desired frequency band, wherein the three-dimensional photonic crystal has a plurality of line defect members which include a first line defect member made of a medium having a refractive index not smaller than that of the columnar structures and formed in a direction perpendicular to the direction in which the columnar structures extend, and a second line defect member formed in the same direction as the first line defect member.

Abstract: A liquid crystal display with low manufacturing cost, small dark area and compact exterior is provided by utilizing a plurality of differently radiating light emitting diodes at different angles. The liquid crystal of present invention includes a thin film transistor panel for displaying image, a backlight assembly for providing light to the thin film transistor panel with a plurality of light emitting diodes with different light radiation angles and a light guiding plate, and a frame unit for encompassing the thin film transistor panel and the backlight assembly. The light emitting diodes are placed either at the mid-point of light incident surface or the corner portion of the light guiding plate.

Abstract: A light guide with input and output faces 2, 3a is polar-symmetric about the first face 2 and has optical properties such that the angle at which a ray is injected into the first face determines the position at which it leaves the second face 3a, or, if operated in the reverse direction, the position at which the ray enters the second face determines the angle at which the ray leaves the second face. The light guide includes a tapered transparent sheet 3, light from the first face entering at the thick end of this sheet, and the second face forming one face of the tapered sheet. An input/output slab 4 adjoins the tapered sheet 3 for fan-out of light from the first face 2 to the tapered sheet, and a transition region 8 is located between flat and tapered sheets. The polar symmetry means that light rays always travel in line with the taper direction, which suppresses banding.

Abstract: A spread illuminating apparatus includes an LED, a transparent resin plate and a light reflecting sheet, wherein the transparent resin plate includes slits adapted to have inserted therein flap portions of the light reflecting sheet, and wherein an adhesive tape with flexibility is placed along at least one flap portion of the light reflecting sheet so as to cover at least one slit of the transparent resin plate, whereby the light reflecting sheet is prevented from warping or undulating in spite of difference in thermal expansion coefficient between the materials of the transparent resin plate and the light reflecting sheet, and also whereby light emitted from the LED and traveling in the transparent resin plate is totally reflected by the flap portions and therefore prevented from leaking from the outer side surfaces of the transparent resin plate.

Abstract: The present invention relates to a backlight and a light guide plate, a method of manufacturing a diffuser and the light guide plate, and to a liquid crystal display apparatus, all enabling a cost reduction by reducing the parts count and curtailing unnecessary manufacturing processing. A diffuser 261 has a light distribution layer 181 including a prismatic surface wherein stripe grooves or asperities are arrayed in parallel with each other, a diffusion layer 182 containing diffusion elements 191 for diffusing incident light, and a light incidence control layer 271 including a prismatic surface wherein stripe grooves or asperities are arrayed in parallel on a side of fluorescent tubes 131. The diffusion layer 182 is formed from the same resin, and only the diffusion elements 191 are formed from a different resin.

Abstract: A display device includes a point light source; a light source substrate; a rear frame including a first side wall and a bottom, the light source substrate being disposed at an inner surface of the first side wall; and a front frame engaged with the rear frame and including a second side wall that faces the first side wall. The first side wall and the second side wall respectively have a first through hole and a second through hole through which a screw is inserted. The light source substrate has a screw hole to be screwed with the screw and is located only at a position corresponding to the first through hole and the second through hole. The light source substrate is fixed by the screw that is inserted into the first through hole and the second through hole and is screwed into the screw hole.

Abstract: A spread illuminating apparatus of side light type includes a transparent resin plate integrally composed of a light conductor plate portion and a housing frame portion, a light reflecting sheet, and a light source, wherein an opening for housing the light source is provided at a side portion of the transparent resin plate, slits are provided along a boundary between the light conductor plate portion and the housing frame portion, and wherein a gate for injecting resin into a molding die cavity for the transparent resin plate is positioned outside the boundary of the light conductor plate portion and the housing frame portion and is positioned also between the opening and one of slits which are provided toward the side portion of the transparent resin plate having the opening and which are located clear of the opening.

Abstract: A high voltage power supply for a static neutralizer is disclosed. The high voltage power supply includes a resonant converter and a load with an emitter module having an emitter, reference electrode, and a capacitance value. The resonant converter is disposed to have a resonant frequency and an output coupled to the load. The resonant converter generates an output waveform with an amplitude sufficient for generating to ions by corona discharge when the load receives the output waveform. The load is predominantly capacitive when the resonant converter is operating at the resonant frequency.

Abstract: A power supply unit that allows a main battery and an auxiliary battery to be charged by a system power supply is disclosed. The first and second bridge circuits of the power supply unit are each formed of four switching elements. The transformer of the power supply unit has a primary winding connected to the first bridge circuit, and a secondary winding connected to the second bridge circuit. The DC/DC converter of the power supply unit allows the auxiliary battery to be connected to the first and second circuits. The controller of the power supply unit controls the switching elements of the first bridge circuit, the switching elements of the second bridge circuit, and the switching element of the DC/DC converter such that power that has been charged to the main battery is output as an AC voltage having voltage and frequency for electric appliances.

Abstract: A soft-switching circuit for a power supply comprises a bridgeless rectifier circuit and an auxiliary circuit. The auxiliary circuit is connected to the bridgeless rectifier circuit, which comprises at least one filtering inductor, two main switches, two diodes and a capacitor. The filtering inductor is connected to the first diode. The first diode is connected to the second diode. The second diode is connected to the first main switch. The first main switch is connected to the second main switch. The diodes and the main switches are connected in parallel with the capacitor to reduce conducting loss. The auxiliary circuit comprises at least one resonant inductor, an auxiliary switch, at least two diodes and a voltage source circuit. The diodes are connected to the resonant inductor and further connected to the voltage source circuit.

Abstract: There is provided a switching power supply device having one half-wave rectifying circuit made up of switching elements complementarily turned on or off, a reactor, a current resonance capacitor, a transformer, and a rectifying diode and another half-wave rectifying circuit made up of switching elements complementarily turned on or off, a reactor, a current resonance capacitor, a transformer, and a rectifying diode and configured so that the half-wave rectifying circuits commonly charges a smoothing capacitor. The switching elements are turned on or off according to a voltage of the smoothing capacitor and other switching elements are turned on or off based on a difference between a charging voltage of the current resonance capacitor and a charging voltage of the current resonance capacitor. As a result, power energy fed from the half-wave rectifying circuits connected in parallel is made equal.

Abstract: A method for thermal protection of a frequency converter and a frequency converter that comprises means for controlling the output current of the frequency converter.

Abstract: A 7-level wye-connected H-bridge converter that provides redundancy for continued operation when one bridge phase has failed and more particularly to a topology that includes multiple semiconductor H-bridges and a three-phase semiconductor mid-bridge. The converter may continue operation with failure of any bridge, as a three-phase, wye-connected H-bridge by bypassing the failed bridge. Individual bridges of the converter may be operated at different dc-bus voltages to maximize power output. The converter may employ synchronous gating signals for the semiconductor devices of the bridges, including a zero-current notch waveform for minimizing harmonic distortion of the output waveform.

Abstract: A controller for a power processing circuit and a related method of operating the same. In one embodiment, the controller includes a multiplier configured to produce a product of an input current and an input voltage of the power processing circuit. The controller also includes a low-pass filter configured to produce an input power estimate of an input power to the power processing circuit as a function of the product of the input current and the input voltage. In another embodiment, the controller is a power-factor controller and includes a voltage loop compensator configured to produce a voltage compensation signal as a function of an output voltage of the power processing circuit. The controller also includes an input power estimator configured to produce an input power estimate of an input power to the power processing circuit as a function of the voltage compensation signal.

Abstract: Method and arrangement for controlling the output voltage pulses of a PWM frequency converter, in which PWM frequency converter is a network bridge (10) for rectifying the alternating voltage of the supply network into the DC voltage (UDC) of the DC intermediate circuit, which is filtered with a filtering capacitor (CDC), a load bridge (11) comprised of phase switches implemented with power semiconductor components, which forms the AC output voltage (U, V, W) from the DC voltage of the intermediate circuit for controlling the load (M), in which for setting the average speed of change in the output voltage in connection with each change of state of the output voltage at least one power component controlled by a phase switch is controlled such that before the output voltage remains in its position subsequent to the change of state it is on at least once for a short period, typically of less than 1 ?s (a micropulse), in the position prevailing before the change of state.

Abstract: A buck converter LED driver circuit is provided. The driver circuit includes a buck power stage, a rectified AC voltage source, a voltage waveform sampler, and a control circuit. The buck power stage includes at least one LED and provides a first signal directly proportional to the current through the LED. The rectified AC voltage source is coupled to the buck power stage for driving the buck power stage. The voltage waveform sampler is coupled to the rectified AC voltage source for providing a second signal directly proportional to the voltage provided by the rectified AC voltage source. The control circuit is coupled to the voltage waveform sampler and the buck power stage for turning on and turning off the buck power stage according to a comparison between the first signal and the second signal.

Abstract: A system and method for producing anharmonic multi-phase currents wherein the harmonic component of an inverter is filtered and superimposed with a series of control pulses to create a control signal. The control signal is fed back to the inverter, causing the inverter to produce anharmonic multi-phase currents.

Abstract: Methods for power factor correction (PFC) and for reducing conduction losses and switching losses in a power converter as well as the power converter and phase management circuitry for the power converter. The power converter includes a first PFC pre-regulator interleaved with at least one additional PFC pre-regulator, and a step down converter. The average input power is measured downstream of the front end at the step down converter and the average current sense signal is compared to a reference voltage. Each additional PFC pre-regulator is disable when output power generated by the front end is less than a first pre-designated rated power level and each additional PFC pre-regulator is enabled when the output power is greater than a second pre-designated rated power level.

Abstract: An isolated ground on/off control circuit includes a first transformer amplifying an AC input voltage, a second transformer connected in parallel to the first transformer; and output circuitry that rectifies the AC input voltage to an isolated DC output voltage. The on/off control circuit may provide improved redundant operation by utilizing a first and a second transformer in parallel and dual diodes for rectification. An on/off command transformer may be designed to have the smallest manufacturable package size and to meet aerospace requirements. The on/off control circuit and method for providing an isolated on/off command to an electronic device as in one embodiment of the present invention may be suitable for, but not limited to, applications in the aircraft and aerospace industries, such as applications in electronic equipments of spacecraft.