Abstract: A vehicle travels along a road with its lights on because of the conditions outside the vehicle. It has an onboard optical sensor associated with the headlights and arranged to form an image of a zone of the road in front of the vehicle, so that the state of humidity of the road can be determined, and the light output modified accordingly. The zone concerned, on the road, consists of at least one segment oriented in the direction of travel, so that the image created by the optical sensor is a characteristic curve representing the light distribution on the road. This image is compared with a reference curve to determine the state of humidity. The reference curve represents light distribution when the road is dry.

Abstract: The present invention relates to an automatic adverse weather rear light system which automatically activates the adverse weather rear light source or light sources. Also, to avoid outshining (masking) either the brake lights or the turn signal/emergency flasher lights the luminosity of these lights is automatically increased to where their luminosity always greater than the luminosity of the adverse weather rear light source or light sources.

Abstract: A system for automatically controlling continuously variable headlamps on a controlled vehicle includes an imaging system capable of determining lateral and elevational locations of headlamps from oncoming vehicles and tail lamps from leading vehicles. The system also includes a control unit that can acquire an image from in front of the controlled vehicle. The image covers a glare area including points at which drivers of oncoming and leading vehicles would perceive the headlamps to cause excessive glare. The image is processed to determine if at least one oncoming or leading vehicle is within the glare area. If at least one vehicle is within the glare area, the headlamp illumination range is reduced. Otherwise, the illumination range is set to full illumination range.

Abstract: The discharge lamp lighting circuit is structured such that positive and negative polarity voltages separately generated from two output terminals of a DC power source circuit are sent to the DC-AC conversion circuit 4. To switch these output voltage, a plurality of switch elements provided in a DC-AC conversion circuit are alternately operated by drive circuits. The resultant AC voltage is supplied to the discharge lamp. A current detection element is provided in the DC power source circuit, and the signal from the element is received by the current detection circuit to conduct current detection.

Abstract: A discharge lamp lighting circuit 1 has a DC power supply circuit 3 for outputting a DC voltage, a DC-AC conversion circuit 4 for converting the output voltage of the DC power supply circuit into an AC voltage and then supplying the AC voltage to a discharge lamp 6, and a current detection circuit 8 for detecting an electric current flowing into the discharge lamp. Just after the discharge lamp 6 is lighted, the output frequency of the DC-AC conversion circuit 4 is temporarily changed for defining the lighting frequency of the discharge lamp as a low frequency, to perform DC lighting over a predetermined time. A control circuit 7 determines the duration of the DC lighting by the time it takes for the product of the time and the value of current flowing into the discharge lamp 6 to equal a predetermined value.

Abstract: A rod (40) is pivotally provided in a lever (28). The rod (40) is divided into a small-diameter lower rod (37) and a large-diameter upper rod (38). When a knob (45) is pivotally moved, the lower rod (37) and the upper rod (38) are moved in an integrated fashion. A movable contact (31) is slid by means of movement of a pusher (57) of the lower rod (37). In this case, the rigidity of the upper rod (38) is improved, and hence the upper rod (38) becomes less susceptible to deflection induced by the load of the spring (53). Accordingly, inclination of the knob (45) toward the lever (28) is prevented, and hence a clearance between the lever (28) and the knob (45) can be maintained constant by means of a single set consisting of a spring (53) and a moderation ball (54).

Abstract: Left and right turn lamps are used as lamps in a daytime travel of a vehicle. When a first daytime turn-on requirement is satisfied, i.e., when an ignition switch is ON, a left-hand contact of a turn switch is OFF, a right-hand contact thereof is off, and the like, a left front turn lamp and a right front turn lamp are turned on as the lamps in the daytime travel, based on signals outputted from first and second AND logic circuits. When the left-hand contact of the turn switch is turned on in this state, the left front turn lamp flashes, based on a signal outputted from a flasher circuit, whereas the right front turn lamp keeps a turn-on state. On the other hand, when the right-hand contact of the turn switch is turned on, the right front-turn lamp flashes, based on a signal outputted from the flasher circuit, whereas the left front turn lamp keeps a turn-on state.

Abstract: A method and apparatus is provided to control the brightness of an emissive display. Specifically, the brightness is incremented and decremented as the ambient environment becomes brighter and darker, respectively. A timing feature is also implemented to control the sensitivity of the system. Specifically, the time between adjustments of the display brightness is at least partially dependent on the magnitude of the difference between the desired brightness based on the ambient lighting environment and that of the actual display brightness.

Abstract: An embodiment of this invention relates to an intelligent lighting device that can receive signals and change the illumination conditions as a result of the received signals. The lighting device can change hue, saturation, and brightness as a response to received signals. One example of using such a lighting device is to display particular colors as a response to certain events. Among others, embodiments may include vehicle lighting systems, an information cube, a back lighting system for a display panel, and an indicator of a condition of a package.

Abstract: An inventive rearview mirror assembly is disclosed in which a microwave antenna is mounted so as to receive transmissions from one or more satellites through the front windshield of the vehicle. The microwave antenna may be tuned to receive satellite transmissions from a position identification system constellation of satellites, such as GPS or GLONASS. Additionally, the microwave antenna may be tuned to alternatively or additionally receive transmissions from at least one communication satellite, such as a CD radio satellite. In addition to the inventive rearview mirror assembly, an inventive electrical control system is disclosed that may be used as a navigation system, an electrochromic rearview mirror control system, a head lamp control system, a tire pressure monitoring and display system, a temperature sensing and display system, a vehicle compass system, a vehicle data recorder system, and/or a vehicle odometer verification system.

Abstract: A vehicle auxiliary lamps installation kit (10) that is designed to be operated in combination with a set of auxiliary lamps (26), a vehicle's alternator (34) and a vehicle battery (36). The kit (10), which is designed to be placed and attached within the engine compartment of a vehicle, is disclosed in four design configurations. The first and second designs allow the auxiliary lamps (26) to be manually turned on for a brief period with a remote pocket transmitter (14). In the third and fourth designs the auxiliary lamps (26) automatically turn on when the vehicle's engine is running with the vehicle generator (34) operating. The fourth automatic design also incorporates a photo sensor circuit (40) that causes the auxiliary lamps (26) to turn on only when the ambient lamp level falls to a preselected level such as when darkness appears.

Abstract: The headlamp system provides a reduced amount of illumination adjacent a driver's line of sight while providing a maintained or increased level of illumination from a source that is offset from the driver's line of sight.

Abstract: A process for diagnosing the proper operation of direction indicator lights of a motor vehicle includes the steps of temporally and alternately shifting the end of illumination of the right and left change of direction indicator lamps of the vehicle, measuring the current passing through a power circuit of the direction indicator lamps during the temporal shift, comparing the measured value with a reference value, and deducing therefrom whether at least one of the lamps is inoperative and in this case informing the driver thereof. A device for diagnosing the proper operation of the direction indicator lights of a motor vehicle is also provided.

Abstract: The invention relates to a lighting system with a high-pressure discharge lamp and a control unit (W, FS, C1, W) for the high-pressure discharge lamp (1), where the lamp base (10) has at least two housing parts (10a, 10b) which are connected to one another by a releasable closure (22). The first housing part (10a) has fastening means (24) for the at least one lamp vessel (11). The high-voltage part (TR) of the ignition device (TR, FS, C1) is accommodated in the first housing part (10a), whilst the second housing part (10b) is provided with the electrical connections (20) for the high-pressure discharge lamp (1) and preferably contains the remaining components (FS, C1) of the ignition device and the voltage converter (W) of the control unit.

Abstract: There is provided a lamp circuit for automobiles which complies with DRL illumination and reduces the number of electrically functional components and circuits. The lamp circuit for automobiles includes a DRL controller complying with DRL illumination, a lamp switch box, and a DRL relay which is also used for the head lamps. The DRL relay has two contact points, a common contact point, and two coils. This allows only one relay to be provided within the area in which two relays have conventionally been applied, thereby reducing the number of relays and necessary circuits.

Abstract: The present invention provides a lighting device of a discharge lamp, which lights the discharge lamp by feeding power to the discharge lamp, comprising a voltage detecting section which detects voltage impressed on the discharge lamp, and a lighting stop determining section which determines, on the basis of the voltage detected by the voltage detecting section, whether or not a short-circuit or a ground-fault occurs in a power feed line to the discharge lamp, and stops lighting in response to the result of the determination, wherein determination whether or not a ground-fault or a short-circuit occurs is not made for a prescribed period of time after dielectric breakdown of the discharge lamp or for a prescribed period of time after flow of a prescribed current to the discharge lamp. It is therefore possible to prevent an erroneous detection caused by use of an unstable bulb voltage in the initial stage of lighting.

Abstract: A vehicle headlamp device 10 can be equipped with a discharge lamp 11, a beam switch device 13 that is used to switch between the high beam and low beam, a light distribution switch device 14 which broadens the horizontal light distribution in the forward direction of the vehicle during cornering, and a lighting device 20 which supplies electric power to the discharge lamp. The light distribution switch device 14 can be controlled such that the horizontal light distribution is broadened in the forward direction when the vehicle speed and steering angle exceed specified values. The lighting device 20 can be controlled such that the electric power supplied to the discharge lamp increases only when the horizontal light distribution is broadened by the light distribution switch device 14.

Abstract: A flickering number in an electric-discharge lamp 7 is counted in a flickering number counting unit 23a, a flickering number in an electric-discharge lamp 8 is counted in a flickering number counting unit 23b, and the lighting of the electric-discharge lamp 7 or 8 is inhibited by a lamp-lighting inhibiting unit 24a or 24b in cases where the flickering number in the electric-discharge lamp 7 or 8 exceeds a regular number.

Abstract: In a discharge lamp apparatus for a vehicle, it is determined that a grounded condition is present when a lamp voltage is less than a predetermined voltage and a lamp current is less than a predetermined current. Electric power supply to the lamp is stopped temporarily in response to the determination of the grounded condition, and then the lighting operation is restarted again. If the grounded condition is determined again, the above operation is repeated. If this repetition continues for a predetermined period, the lighting operation is disabled continuously. In controlling the lamp, a voltage of a battery is boosted by a voltage booster transformer, which is turned on and off by a MOS transistor so that electric power supplied to the lamp is duty-controlled. An upper limit is set to the duty ratio, and the upper limit is increased as the lamp current decreases, so that the lighting characteristics of the lamp is improved.

Abstract: A system for automatically controlling continuously variable headlamps on a controlled vehicle includes an imaging system capable of determining lateral and elevational locations of headlamps from oncoming vehicles and tail lamps from leading vehicles. The system also includes a control unit that can acquire an image from in front of the controlled vehicle. The image covers a glare area including points at which drivers of oncoming and leading vehicles would perceive the headlamps to cause excessive glare. The image is processed to determine if at least one oncoming or leading vehicle is within the glare area. If at least one vehicle is within the glare area, the headlamp illumination range is reduced. Otherwise, the illumination range is set to full illumination range.

Abstract: According to the system and the method of the present invention, a display's visibility is maintained depending on lighting conditions that are sensed by an ambient light sensor (16). Logic (10) is applied to the output of the light sensor (16) and in conjunction with a headlight status indicator (14) to determine whether daytime (D) or nighttime (N) lighting condition exists and to determine a brightness level (18) to be commanded to the display. The logic (10) of the present invention maintains a visible display even in situations where a vehicle's headlights are active during daylight lighting conditions.

Abstract: A flasher circuit for switching incandescent lamps with field effect transistor switches is described for use on a school bus. A current sensing resistor develops an actual load current signal and a current limiting circuit which generates a signal corresponding to a predetermined limit value of load current. A control circuit turns off the field effect transistor when the actual value of load current exceeds the predetermined value. A micro controller holds the reference voltage at a higher level during the inrush current interval and switches it to a lower level during the steady state current.

Abstract: A lighting system provides an auxiliary lighting circuit for turning on an auxiliary light source in place of the discharge lamp if the abnormality in the lighting circuit is detected.

Abstract: An automotive external lighting system uses pulse width modulation to drive a single filament for turn signaling and park signaling purposes. A control circuit generates a variable brightness signal based on a predetermined brightness level, and an external lamp produces external illumination based on the brightness signal. A single wire is therefore able to electrically connect the control circuit to the external lamp. The control circuit includes a microcontroller for generating a pulse width modulated signal, and a high side driver for driving the lamp in response to the pulse width modulated signal. When the pulse width modulated signal has a duty cycle corresponding to a parking brightness level, the filament will produce less illumination than in the case of turn signaling.

Abstract: An apparatus for operating a discharge lamp from an on-board voltage source of a motor vehicle. The discharge lamp is operated at a first electrical power to produce a taillight and is operated with a second, higher power to produce a signal light.

Abstract: A light emitting display includes a display body made of a light diffusing resin material which comprises a transparent resin doped with a light diffusing material, and an LED lamp having an LED chip encapsulated in a mold member made of a light transmissive material and embedded in the display body with its top facing a front side of the display body. A light reflective surface is disposed on a rear side of the display body to face the front side, and the LED lamp is covered at its top with a light reflective coating.

Abstract: A neon cruising lighting system for use with a motor vehicle battery includes a motor vehicle headlight having a reflector, a cutout in the reflector, an inert gas discharge lamp capable of irradiating various light colors, disposed in the cutout, a plug assembly adapted to cooperate with a motor vehicle cigarette lighter power receptacle, a transformer electrically coupled to both the plug assembly and the inert gas discharge lamp, so that the plug assembly conducts electrical power from the battery to the transformer to the inert gas discharge lamp, in order to illuminate the inert gas discharge lamp.

Abstract: A one-piece headlight adapter, and a two-piece headlight adapter system, is used to connect the existing vehicle headlight controls and power supply with a snowplow wiring harness. An adapter only connects the controls and power supply for one headlight to the wiring harness. Two adapters, one for each headlight, create an adapter system. The adapter system allows the vehicle operator to control the snowplow headlights from the inside of the vehicle. One version of an adapter is a three-component adapter that includes one connection to the vehicle headlight, one connection to the headlight controls, and one connection to the wiring harness. Another version of the adapter is a five-component adapter that includes high and low beam connections to the vehicle headlight, high and low beam connections to the headlight controls, and one connection to the wiring harness.

Abstract: An improved ambient light sensor 20 is provided. Light 105 passes to at least two photosensors 30, 35 with different peak response frequencies. A controller 80 accepts output signals from the photosensors 30, 35 and operates vehicle systems (e.g., headlights 70 or environmental controls 75) accordingly. The controller 80 may distinguish between natural and artificial light, so that headlights 70 are illuminated while a vehicle passes through a well lit tunnel, or is exposed to lights from another vehicle.

Abstract: A system for automatically controlling continuously variable headlamps on a controlled vehicle includes an imaging system capable of determining lateral and elevational locations of headlamps from oncoming vehicles and tail lamps from leading vehicles. The system also includes a control unit that can acquire an image from in front of the controlled vehicle. The image covers a glare area including points at which drivers of oncoming and leading vehicles would perceive the headlamps to cause excessive glare. The image is processed to determine if at least one oncoming or leading vehicle is within the glare area. If at least one vehicle is within the glare area, the headlamp illumination range is reduced. Otherwise, the illumination range is set to full illumination range.

Abstract: An industrial truck is provided with a direct current power supply and at least one electrical user (2), e.g., a lighting device located in a housing, wherein the power supply voltage of the power supply (3) is greater than the nominal voltage of the user (2). To connect the user (2) to the power supply, there is a voltage transformer (4) which is located inside the housing or in the immediate vicinity of the housing. The invention also relates to a voltage transformer which applies a power supply voltage to a user (2) in pulses, so that the power delivered to the user, as an average over time, does not exceed the nominal power of the user (2).

Abstract: A hybrid IC of electronic circuit for a discharge lamp is disposed on the bottom of a metal case. A transformer, an inductor, a transformer, and a capacitor are disposed in a resin case. The resin case is contained in a metal case. In this instance, the transformer, the inductor, the transformer, and the capacitor are located outside the outer periphery of the IC so that the IC does not overlap on the transformer and other components. The transformer for a starter circuit has a secondary winding the inductance of which is 2.5 mH or larger, and a capacitance of a smoothing capacitor of a DC—DC converter is 0.5 &mgr;F or smaller. The switching frequency f of a MOS transistor is selected so that L2×C1 is equal to or larger than 1×10−1×f−1.68.

Abstract: A vehicle electrical system for supplying a first load with a first direct current voltage and for supplying a second load with a second direct current voltage lower than the first direct current voltage is disclosed.

Abstract: A starter for a gas discharge lamp, in particular a high-pressure gas discharge lamp for a motor vehicle headlight. The gas discharge lamp is supplied with operating power over the secondary side of a transformer. The required starting power is supplied on the primary side of the transformer and is transferred to the secondary side at the starting time. The starting voltage is generated by a cascade circuit, with the cascade circuit of capacitors and diodes provided in the starter circuit to generate the starting voltage at a charge capacitor. The starter circuit is supplied by the bridge circuit which supplies the gas discharge lamp with power for operation, and for the purpose of starting, the bridge circuit is cycled at a frequency which is much higher than the normal frequency for lamp operation. After the lamp has been started, the bridge circuit is switched to the normal frequency in lamp operation. The starter can be implemented in a two-wire concept, a three-wire concept or a four-wire concept.

Abstract: The rear vehicle height HR is detected by the vehicle height sensor as vehicle inclination information by a CPU. Based on the rear vehicle height HR, the inclination angle of the headlight optical axis direction is computed with an inherent control constant corresponding to vehicle specifications preset by a specification discrimination signal. Then, the headlight optical axis direction is adjusted with reference to the pitch angle.

Abstract: A vehicle lamp has light sources having light emitting diodes that are vertically and horizontally disposed in the form of a square. A first LED group is disposed in the central position of the light source and is turned on in the tail lamp lighting mode. A second LED group surrounds the first LED group, and is turned on together with the first LED group in the stop lamp lighting mode. Thus, the light source appears as if the LEDs became luminous around the central position of the light source in any lamp lighting mode.

Abstract: A vehicular headlamp of a type having a lighting circuit unit mounted on an outer surface of a bottom wall of the lamp body in which failure of the seal between the lamp body and a front lens mounted thereon is prevented. A bottom wall extension portion is formed at a rear end portion of a bottom wall of the lamp body, extending rearward beyond a bulb replacement opening formed in a rear wall of the lamp body. This structure provides sufficient rigidity for the rear end portion of the bottom wall, which otherwise would have insufficient rigidity because of its location adjacent the bulb replace opening. Therefore, the bottom wall is protected from deflection deformation due to the weight of the lighting circuit unit. As a result, the front end opening of the lamp body is protected from deformation.

Abstract: Control apparatus for a light unit for vehicles, in particular motor vehicles, includes an electronic control unit for controlling the light unit, with the control unit having an I/O interface for connecting to a plurality of control and/or switching devices assigned to the light unit. The electronic control unit is arranged in a rectangularly-shaped housing which is detachably mounted in a receptacle of the light unit. A first contacting device is provided on a first side of the electronic control unit for connecting the electronic control unit to a number of electric components integrated into the light unit, and in addition a second contacting device is provided on a second side for connecting the electronic control unit to a number of additional electric components arranged near the light unit.

Abstract: A one-piece headlight adapter, and a two-piece headlight adapter system, is used to connect the existing vehicle headlight controls and power supply with a snowplow wiring harness. An adapter only connects the controls and power supply for one headlight to the wiring harness. Two adapters, one for each headlight, create an adapter system. The adapter system allows the vehicle operator to control the snowplow headlights from the inside of the vehicle. One version of an adapter is a three-component adapter that includes one connection to the vehicle headlight, one connection to the headlight controls, and one connection to the wiring harness. Another version of the adapter is a five-component adapter that includes high and low beam connections to the vehicle headlight, high and low beam connections to the headlight controls, and one connection to the wiring harness.

Abstract: Left and right turn lamps are used as lamps in a daytime travel of a vehicle. When a first daytime turn-on requirement is satisfied, i.e., when an ignition switch is ON, a left-hand contact of a turn switch is OFF, a right-hand contact thereof is off, and the like, a left front turn lamp and a right front turn lamp are turned on as the lamps in the daytime travel, based on signals outputted from first and second AND logic circuits. When the left-hand contact of the turn switch is turned on in this state, the left front turn lamp flashes, based on a signal outputted from a flasher circuit, whereas the right front turn lamp keeps a turn-on state. On the other hand, when the right-hand contact of the turn switch is turned on, the right front turn lamp flashes, based on a signal outputted from the flasher circuit, whereas the left front turn lamp keeps a turn-on state.

Abstract: A plurality of lamps 21 to 28 inclusive are supplied with a voltage one after another in sequence. A time duration during which the voltage is supplied to each of the lamps 21 to 28 inclusive is controlled in PMW fashion to restrict an amount of voltage supplied thereto. A current detect circuit portion 36 solely detects all of the voltages supplied to the lamps 21 to 28 inclusive, respectively. Each of the voltages exceeds a threshold value, a dead band between two adjacent voltage supply durations. Thus, it is possible to restrict possible electromagnetic noises which are generated upon voltage supply to lamps 21 to 28 inclusive in a vehicular lamp control apparatus in which the lamps 21 to 28 inclusive are supplied with voltage from a high voltage battery 11.

Abstract: A system for enabling successful use of HID lamps in aircraft, including in particular high power lamps for use as landing lights and taxi lights, utilizes a sealed beam HID lamp which during normal operation has an external temperature considerably lower than the external temperature of a quartz halogen or incandescent sealed beam lamp of equivalent light output. The lower external temperature arises in part from the use of a gas fill in the sealed beam. A detector is provided to monitor the seal integrity of the sealed beam HID lamp and further to provide a response to seal failure resulting in disablement of the lamp. Exemplary means for accomplishing seal failure detection include radioactive detection, pressure monitoring, and chemical sensing, or other means wherein detection of a failed seal is followed by an electrical output used to terminate or preclude lamp operation.

Abstract: A vehicle lamp lighting-driving apparatus is provided, which includes: a lighting driving means to lighting-drive a lamp; a driving signal generating means to generate a pulse driving signal having a pulse with a duty factor to make a power consumption of the lamp be a rated value of the lamp; and a driving controlling means to on/off-drive the lighting driving means according to the pulse driving signal, wherein the driving signal generating means generates an auxiliary driving signal which makes the driving controlling means control the lighting driving means so that a current to flow to the lamp through the lighting driving means is limited for a definite time, until a rush current at a time of on-driving of the lighting driving means gets equal to or smaller than an allowable value, prior to the pulse driving signal at a start of lighting the lamp.

Abstract: A method for providing a signal, representing the longitudinal inclination of a vehicle, for a control unit for the slip control and/or for the control of a quantity describing the yaw rate of the vehicle, measured quantities which can be acquired and processed for ascertaining a signal representing a longitudinal inclination of the vehicle, and/or the ascertained signal representing the longitudinal inclination being transmitted from a control device for the headlight-leveling control to the control unit for the slip control and/or for the control of the quantity describing the yaw rate.

Abstract: An arrangement for detecting the condition of a high pressure gas discharge lamp when switched on is described, where a control unit either injects a defined current into the lamp and measures the resulting voltage drop, or it applies a defined voltage to the lamp and measures the lamp current flowing in so doing and, depending on the result, it starts the lamp according to the condition of the lamp thus determined.

Abstract: A steady-state condition in which respective discharge lamps for main beam and for dipped beam are both turned on, a sum (P1+P2) of a value of power supplied to each discharge lamp is controlled to be smaller than a sum (P1R+P2R) of a rated power value for each discharge lamp.

Abstract: An automatic automobile headlamp leveling device is provided for a headlamp which is driven by an actuator so that a light axis of the headlamp can be tilted up or down relative to a vehicle body. A vehicle speed detection sensor is provided for detecting the vehicle speed, a pitch angle detection sensor is provided for detecting a pitch angle of the vehicle, a storage section is provided for storing a plurality of pitch angle data of the vehicle detected by the pitch angle detection sensor, and a control section is provided for controlling the driving of the actuators. The control section controls the driving of the actuators based on the pitch angle data so that the light axes of the headlamps always stay in a certain tilted state relative to the surface of a road.

Abstract: A flasher circuit for switching incandescent lamps with field effect transistor switches is described for use on a school bus. A current sensing resistor develops an actual load current signal and a current limiting circuit which generates a signal corresponding to a predetermined limit value of load current. A control circuit turns off the field effect transistor when the actual value of load current exceeds the predetermined value. A micro controller holds the reference voltage at a higher level during the inrush current interval and switches it to a lower level during the steady state current.

Abstract: To provide a lighting device which is enabled to light a lamp of an incandescent bulb or the like in high luminance by a battery to be amounted on a vehicle. A lighting source lighting device 10 includes: an inverter 11 for converting a direct current from a vehicle-mounted battery 15 into an alternating current; and current adding means 13 for adding the direct current from the vehicle-mounted battery 15 and alternating current generated by the inverter 11, to supply a light source 14, such as a head lamp, with the added electric current. In this construction, the light source 14 is driven with the electric current containing the direct current and alternating current superimposed thereon so that the light source luminance microscopically changes with the period of the alternating current.

Abstract: The invention consists of an electrical circuit for a vehicle headlight system whereby the conventional parallel circuit connection of headlights is automatically converted into a series circuit connection under conditions appropriate for daytime running lights, whereby the light output of the headlights is reduced as compared to that in conventional headlight circuit mode, and a method for interconnecting such circuit with conventional headlight systems.