Abstract: A light-emitting device includes a growth substrate, a plurality of light-emitting diode units formed on the growth substrate and arranged in a closed loop, an electrode directly formed on the growth substrate, an electrical connection structure formed on the growth substrate and connecting the plurality of light-emitting diode units with the electrode, and a plurality of rectifying diodes connecting to respective nodes of the closed loop.

Abstract: Light emitting device (LED) light fixture control systems and related methods are disclosed. A system and method in one aspect can include at least one LED configured to emit light at an illumination output level and at least one light sensor configured to measure the illumination output level of light emitted by the LED. A system and method can also include a control unit configured to detect the illumination output level emitted by the at least one LED falling below an original illumination output level and to increase the illumination output level by the at least one LED to produce a predetermined lighting level associated with the original illumination output level in an area.

Abstract: One or more example diagnostics may be implemented as part of an intelligent luminaire manager or other radio frequency (RF) device that is in communication with an equipment or fixture such as a luminaire. Example diagnostics can determine a status such as a fixture malfunction, a cycling condition, a miswiring configuration, or another condition. The determined status can be wirelessly transmitted from the intelligent luminaire manager or other radio frequency device to a network server via a network. The network may be a network of intelligent luminaire managers and/or RF devices.

Abstract: One or more example diagnostics may be implemented as part of an intelligent luminaire manager or other radio frequency (RF) device that is in communication with an equipment or fixture such as a luminaire. Example diagnostics can determine a status such as a fixture malfunction, a cycling condition, a miswiring configuration, or another condition. The determined status can be wirelessly transmitted from the intelligent luminaire manager or other radio frequency device to a network server via a network. The network may be a network of intelligent luminaire managers and/or RF devices.

Abstract: An electronic ballast (10), for a gas discharge lamp (18), comprises a constant current source (14) and a switch (16). A transformer (60), for use in an igniter (90) for a gas discharge lamp (18, 40), comprises a core (62) which has interconnected legs (64, 66, 68), a first secondary winding (70) around a first leg (64), a second secondary winding (72) around a second leg (66), and a primary winding (74) around a third leg (66). An igniter (90) for a gas discharge lamp (18, 40) comprises a transformer (60) as described above and a drive circuit (92) for driving the primary winding (74).

Abstract: Disclosed is a low cost LED string circuit design that uses an inexpensive half-wave rectification and low-pass filter circuit that is designed to produce minimal flicker in the LED string that is connected to the circuit. The components of the half-wave rectification and low-pass filter circuit are selected in accordance with design principles that prevent glittering and flickering of the LED string. The circuit components of the half-wave rectification and low-pass filter circuit can be embedded in an outlet plug or as a separate independent unit between an AC power plug and the LED string.

Abstract: Apparatus and methods for measuring cathode fall in fluorescent lamps are disclosed. Together with measurements of cathode temperature, such measurements of cathode fall may inform a determination of cathode heater voltage as a function of discharge current (i.e., a cathode-heating-profile) that avoids both sputtering and excess-evaporation.

Abstract: The instant invention relates to an HID ballast and lamp tester, which provides visual indication of failure of either the ballast or lamp by continuously monitoring the status of the HID lighting system. The HID ballast and lamp tester detects and utilizes the voltage difference between the open circuit voltage and the operating voltage of the ballast to trigger visual indication of the open circuit voltage output of the ballast when the HID lamp has failed. The tester circuit comprises the ballast source, a full wave bridge rectifier and filter capacitor circuit, a voltage divider network circuit, a trigger circuit of a diac bi-directional silicon switch and a light emitting diode.

Abstract: There is disclosed a germicidal treatment system having a status indicator. The germicidal treatment system comprises at least one mounting assembly attachable to an outside of a wall of an air handling apparatus. Each of the mounting assemblies includes a germicidal lamp and a ballast. The germicidal lamp is coupled to the ballast. The germicidal treatment system includes a power cord to receive electrical power and to provide electrical power to the ballast. A status indicator to indicate the functioning status of the germicidal treatment system.

Abstract: A warning device including a status and function indicator circuit for indicating the status and function of the warning device. In a visual warning device such as a strobe light, the status and function indicator circuit includes a status output device such as an LED. The LED and associated circuitry are configured to indicate both proper operation of the visual warning device and, in the event of a device failure, will indicate whether the fault lies with circuitry for the visual warning device or simply with a warning output device.

Abstract: Several types of ballast circuits for operating one or many LEDs in AC circuits finding particular use in aircraft lighting panels are disclosed. The first type is a linear transfer function ballast using inductors to limit diode current, and capacitors to ensure unity input power factors. The second type is a non-linear transfer function ballast using inductors to limit current, capacitors to ensure unity input power factor, and diodes shunted across one or many series connected inductors to steepen the transfer function. The aim of steepening the transfer function is to imitate the voltage—brightness characteristic of incandescent bulbs, thereby providing a direct replacement aerospace lighting solution compatible with existing AC light dimmers. It is also possible to configure the ballasts of the present invention to function with a DC input voltage.

Abstract: A circuit configuration for emitting light signals in a road traffic systems. A plurality of LEDs for emitting colored light are supplied with an a.c. voltage. The LEDs are arranged in two groups of LEDs which are connected antiparallel to one another. Two respective LEDs of the two groups are disposed together in a housing and the groups are cross-connected to form a multiply redundant matrix. An intrinsically safe signal transmitter configuration is provided that is simple and can easily be monitored.

Abstract: A switch for use in an AC circuit wired in a three-way switch mode for supplying power to a load, has a first terminal for connection to an external line, second and third terminals for connection respectively to corresponding terminals of a second like switch, and a switch contact for selectively connecting the first terminal to either one of the second and third terminals. A transformer has its primary winding connected between the first terminal and the external line, and its secondary winding deriving an output voltage therefrom. The output voltage is rectified and supplied to a light-emitting diode. The ratio of turns of the windings of the transformer is such that the rectified voltage energizes the light-emitting diode when power is supplied to the load over its normal operating range. The light-emitting diode will thus provide an indication of when power is supplied to the load.

Abstract: A device for examining optical waveguides comprises a prism to be positioned on the waveguide to be investigated, an entering point at which incoming light enters the device, and control devices for altering the angle of light directed to the prism from the entering point of incoming light, wherein the control devices include a mirror whereby the projection of the reflecting surface of the mirror in the plane of altering the angle is in the form of an ellipse, a rotatable mirror is placed at the focal point of the ellipse and the corner of the prism is situated at the second focal point of the same ellipse.

Abstract: Alarming mechanism, sounding and/or flashing, which signals fluorescent lamp malfunctioning as visibly manifested by flickering. The alarming mechanism according to this invention electrically engages the starter mechanism of a fluorescent lamp and is responsive to current change associated with abnormal flickering. Timely corrective action which is prompted by the alarm may avoid or mitigate one or more deleterious effects of such malfunctioning, such as energy waste, lamp damage, fire hazard and electronic interference. For many embodiments the alarming mechanism and the starter mechanism are advantageously coupled as a single structural unit.

Abstract: A flash monitor alarm system is provided for detection of emergency vehicle flashers or for detection of flashes in photography. For emergency flasher detection the unit is positioned in a vehicle within a direct line of sight of potential emergency flashers. When emergency flashers are detected, an alarm is activated to warn the vehicle's occupants. For a photographic monitor alarm system, a detector is inductively coupled to a flash tube assembly's flash tube or tube power cable for activating a pulsating flash monitor indicator perceptible to the photographer when the flash tube has properly fired. The flash monitor alarm system includes flash monitor electronics and a power source, both of which are built into a compact housing.

Abstract: This is an emergency lighting system that provides an emergency driving voltage to drive at least one lamp when the AC power input to the lamp is detected as absent. A rechargeable battery pack and recharging circuit are contained in a first modular housing, and driving circuitry is contained in a second modular housing. An easily accessible, manually-operable service switch disables the provision of battery power to the driving circuitry (when the switch is in the open state), thereby allowing substantial reduction in installation time and cost. A test switch is included to emulate power failures. A transmitter and receiver mechanism allow a user to remotely disable the provision of battery power to the driving circuitry, thereby offering battery power conservation, if the emeregency lamplight is not needed. Likewise, a photo-sensing mechanism disables the provision of battery power to the driving circuitry, if there is sufficient ambient light.

Abstract: This safety lighting arrangement is especially suited for use with variously rated HID light sources having current ratings ranging from relatively low to relatively high values. The safety light arrangement includes a current transformer having a magnetizable core, a primary winding inductively coupled to the core for connection in series with the primary circuit in which the HID light source is connected, and a secondary winding inductively coupled to the core. The core is saturable by the primary winding current present when the current through the HID light source is as low as the current rating of one of the relatively low rated HID sources. The safety light arrangement also includes a monitoring relay connected across the secondary winding and maintained in an activated condition when the primary winding is traversed by current producing saturation of the core. This monitoring relay is set to drop out when current through the primary winding and the HID source is interrupted by a power interruption.

Abstract: An indicator lamp indicates the status of an electrically-powered load control system by providing dim light when the load power is off and a brighter light when the load power is on. In another embodiment, the lamp not only provides two levels of light to indicate whether or not power is on, but also provides a repetitive flash when power to the system is being controlled by remote control. The indicator lamp can also indicate a break in the load circuit. Depending on the embodiment, the break can cause the lamp to be either off or flashing, regardless of the position of the load power switch. Alternatively, a break in the load circuit can cause the lamp to provide substantially no light if the load power switch is in the "off" position, with full light in the "on" position.

Abstract: A self-relamping clearance/marker light assembly includes a pair of lamps connected to a proving ring switch. A primary one of the almps is lighted and the switch prevents current flow through a secondary one of the lamps until the primary lamp burns out. The lamps are operated at a derated voltage to increase life and a small compensating lamp provides the necessary additional illumination lost through the reduced voltage operation of the primary and secondary lamps. The lamps are mounted for isolation from high frequency vibration and shock impacts using the lamp lead wires to form part of the shock mounting.

Abstract: A failure compensation circuit automatically reduces the output voltage of a power supply when a portion of a load drops out. The compensation circuit includes a circuit for generating a control signal representative of the desired voltage across the load. A power supply supplies voltage to the load in response to the control signal. An input signal representative of the current delivered to the load is produced which decreases whenever a portion of the load drops out. The circuit for generating the control signal is responsive to the input signal for adjusting the control signal such that when the current delivered to the load decreases, the voltage delivered to the load is automatically reduced.

Abstract: In order to provide a lamp failure warning in both illuminated and unilluminated states of the lamp, there is provided a resistance bridge circuit Rs, L, R2 and R3 which is substantially in balance if the lamp L is sound. An amplifier IC1 acts as a detection means if the bridge goes out of balance as a consequence of failure of the lamp L. In the unilluminated state a reduced current is fed to the bridge via a high value resistance R1, which is by-passed by a lamp switch SW1 if the lamp is to receive enough power to illuminate it.

Abstract: A data inserting device for a camera arranged to automatically insert data in response to an insertion trigger signal from the camera body includes abnormity detecting means which supplies current to a specific part where such abnormity that hinders the data inserting action tends to occur and is arranged to detect the abnormity by an impedance change occurred at the part, and external display means for displaying the abnormity upon detection thereof by the detecting means.

Abstract: A battery power indicator for a DC to DC flyback converter is responsive to the current flowing in the secondary winding of the converter's transformer. In one embodiment the power indicator is lighted when the battery is weak but not dead. If the battery is good, the indicator is bypassed and remains off. In a second embodiment, the indicator is lighted to indicate a good battery and when the power capability of the battery drops below a predetermined level, the indicator turns off.

Abstract: A light quantity controller and an input device are disclosed. The light quantity controller comprises a light source, a photo-sensor to detect a light quantity of the light source, a signal source for generating a reference signal, a comparator for comparing the detected light amount with the reference signal, and control circuit to control a duty ratio of the energization to the light source in accordance with the compare result to maintain the light quantity of the light source at a constant level. The light quantity controller further comprises a comparator to compare the energization signal to the light source with a reference signal to detect the degradation of the light source. The input device has a key matrix including a plurality of input ports and a plurality of output ports of a control unit interconnected through switches. A signal source independent from the output ports of the key matrix is connected to at least one of the input ports through switches.

Abstract: The invention relates to a device for checking a plurality of indicator lights, wherein the intensity passing through each indicator light is sequentially measured and the measurements are compared with nominal intensities. The invention is more particularly applicable to the checking of the indicator lights of devices monitoring functional members.

Abstract: In the disclosed device, a DC-DC converter boosts the output of a battery to charge a capacitor that stores electrical energy to be converted into light energy and turns on a neon tube when the capacitor voltage reaches a first predetermined value. A control arrangement disables the converter in response to the neon tube turning on the re-enables the converter when the capacitor charge drops to the first predetermined level after the neon tube turns on.

Abstract: An electronic flash device provided with an auxiliary winding electromagnetically coupled to a winding in a DC-DC converter which is connected to a main power supply and generates a voltage for charging a main flash capacitor, an auxiliary capacitor adapted to be charged with at least the voltage induced across the auxiliary winding, and a control circuit for maintaining the voltage charged across the auxiliary capacitor at a predetermined level, whereby the voltage charged across the auxiliary capacitor can be delivered to integrated circuits for the flash device.

Abstract: An improved dual polarity substitution circuit for energizing a secondary load, such as an incandescent lamp, upon failure of a primary load. Dual polarity is achieved through the use of parallel PNP and NPN transistors, one of which conducts so long as the primary load is functional. Upon failure of the primary load and interruption of current flow in the conducting one of the transistors, a bidirectional switch such as a triac is fired to energize the secondary load.

Abstract: Push buttons (9u, 9d) are provided to select the desired intensity of a lamp (1) for electrostatic copying or the like. The selected intensity is numerically displayed. A preset function is provided to preset the intensity to a standard value when power is first applied to the apparatus. The intensity may thereafter be manually varied using the push buttons (9u, 9d). The lamp intensity is controlled by means of phase angle control of a thyristor (2). Provision is made to compensate the phase angle control for variations in the A.C. power supply voltage.

Abstract: A light dimming system for simultaneously controlling the brightness of a plurality of two-terminal indicating lights, each having one terminal connected to receive a constant voltage relative to ground. The system includes a single dimmer control for producing an arbitrarily variable control voltage, and a like plurality of interface circuits, connected between the dimmer control and the other terminals of the indicating lights, respectively, for varying the voltage at the other terminals of the indicating lights proportional to the control voltage supplied to the interface circuits from the dimmer control.

Abstract: A visual monitor including a single light indicator for HID lamps (not needing a starter) and a visual monitor including two light indicators for an HID lamp, such as a high pressure sodium lamp, operating in conjunction with the starter. When the lamp is out, the presence or non-presence of an ignited first light indicator indicates lamp failure or ballast failure, respectively. The blinking or nonblinking of the second light indicator indicates whether or not the starter is producing satisfactory starting pulses.

Abstract: A fault detection apparatus for use with a double-filament lamp utilizes the temperature-related changes in resistance of the non-energized filament to indicate a break in the energized filament. The circuit of the apparatus includes, for each filament, a first voltage dividing network in parallel with the filament and which includes the other filament as a voltage dividing resistance and a second voltage dividing network including the filament which establishes a reference voltage. A comparator is activated to energize a warning lamp when the sensed voltage at a specific voltage dividing point in the network is changed due to the temperature-related changes in the resistance value of the non-energized filament when the energized filament is broken.

Abstract: An electric corrosion preventing apparatus with a circuit having an indication lamp for indicating an operation state of the apparatus, which is used for preventing an inside wall of a hot-water receptacle, such as a water heater and a boiler, from being corroded by rust. In the circuit, the secondary winding of a voltage-dropping transformer is provided with a couple of diode-capacitor combinations. Those diode-capacitor combinations, respectively, are used for rectifying positive and negative parts of a low AC voltage produced by the secondary winding into positive and negative DC voltages. A positive DC voltage is coupled with an electric corrosion prevention load while a negative DC voltage is coupled with a lamp load. With this circuit arrangement, the positive part of the AC voltage is used for the electric corrosion prevention while the negative part, for the lamp.

Abstract: In a circuit for an ionization vacuum gauge having a thermionic filament, a control circuit receptive of a control current for controlling the filament and a switch for applying the control current to the control circuit, a circuit is provided for indicating a filament interruption independent of the state of the switch. The circuit includes at least one resistor by-passing the switch to provide a continuous sensing current to the filament and a detector for detecting the interruption in the sensing current and for indicating such an interruption.

Abstract: A lamp circuit is provided having a constant current type AC power source and a plurality of isolation transformers connected in series with the AC power source. The secondary circuit of each isolation transformer is connected to an electric lamp. The voltage-time area, which is measured from the rise of the voltage output signal of the power source to the rise of the current output signal of the power source is detected and is compared with a reference predetermined value. Thereby when the detected value exceeds the reference value an alarm signal is generated and the number of the disconnected lamps can be determined and displayed.

Abstract: An audio-visual alarm includes a flashtube and a voltage signal generator for producing and storing voltages sufficient to operate the flashtube. In series with the flashtube and the voltage generator is the coil of an audio alarm, whereby operation of the flashtube also operates the audio alarm. The audio alarm is selected so that its coil will not interfer with the operation of the flashtube.

Abstract: In a flash light discharge device including a strobo tube attached to a camera body, both the positive and negative outputs of a blocking oscillator are made use of. One output is used for charging a main capacitor for making the strobo tube discharged, and the other output is used for energizing an indicator or indicators. Both the outputs may be used for charging the main capacitor to accelerate the charging of the capacitor. The indicator energized by the output of the blocking oscillator while the main capacitor is charged may be an indicator which indicates by intermittent lighting that the main capacitor is being charged.

Abstract: A photographic flash device comprising a main capacitor for flashing a flash discharge tube, a DC-DC converter, a constant-voltage circuit for controlling the oscillation function of the DC-DC converter and an indication means capable of discriminatively indicating states of the voltage of the main capacitor in three different voltage ranges, first range being from zero to a first predetermined voltage above which flashing is possible, second range being from a first predetermined voltage to a second predetermined voltage, the third range being from the second predetermined voltage to a third predetermined maximum voltage, respectively.

Abstract: An operation indicator for auto-strobo unit which includes a single light emitting element capable of indicating the completion of a charging operation or a flashlight illumination of the auto-strobo unit, comprises a bypass circuit which any current flow associated with the indication of the completion of a charging operation is bypassed whenever a current flow associated with the indication of the completion of a flashlight illumination is produced, thus allowing the indication of the completion of a flashlight illumination to predominate over the indication of the completion of a charging operation.

Abstract: A lighting network is described which includes a main gas discharge lamp, a standby lamp and a control circuit. The control circuit senses when the gas discharge lamp is operating normally and turns off the standby lamp. When the discharge lamp is not up to full light output after ignition or has gone out due to a momentary power interruption, the control circuit turns on the standby lamp. The control circuit includes a transistor amplitude discriminator and an electronic switch. The discriminator, which senses the voltage at the discharge lamp terminals, has a transfer characteristic which produces a "low" output over a "normal" range of terminal voltages and a "high" output for terminal voltages below and above the normal range. The electronic switch responds to "high" and "low" discriminator outputs to turn on or turn off the standby lamp, respectively.

Abstract: A lamp failure detection arrangement includes a device for interrupting electrical energy to a lamp, and a testing device for generating a low level test signal and for supplying it during the testing interval to the lamp for test purposes without causing the lamp to provide illumination. A device responds to the test signal indicating a failure condition of the lamp for generating a failure condition signal, which can be used both to energize a standby lamp and to generate an attention-attracting signal for alerting an attendant to replace the faulty lamp.

Abstract: An external sensor which may be detachably electrically connected to an electronic flash of the type having a flash duration control circuit for controlling the flash duration of a flash tube which flashes by discharging the electrical energy stored on a main capacitor, the external sensor including a light receiving unit which, in the automatic flash exposure mode, receives the light emitted from the flash and reflected back from a subject. In the automatic flash exposure mode in which the flash duration control circuit is activated in response to an interrupt signal from the light receiving unit, the external sensor selectively displays correct flash exposure data such as film speed, aperture and distance to a subject.

Abstract: An electronic flash device comprising a DC-DC converter circuit which converts a low voltage DC source to a high voltage DC current for charging a main discharge capacitor, a flash discharge tube which is adapted to flash by means of the energy stored in the main discharge capacitor, and a display circuit. The DC-DC converter circuit includes an oscillation transformer having a primary winding, a secondary winding magnetically connected with the primary winding, an auxiliary winding and further a second auxiliary winding, an oscillation transistor, and an auxiliary capacitor connected with the auxiliary winding for causing the oscillation transistor to be started; and the display circuit is lit for display when the voltage generated across the second auxiliary winding and the voltage applied across the auxiliary capacitor are superposed to reach a predetermined value.

Abstract: An indicator circuit for indicating whether an incandescent type lamp is burned out. The indicator circuits include a voltage reference source and an indicator LED which is normally biased just below the knee of its conduction curve, but which is biased into conduction whenever the monitored lamp burns out. A bridge circuit is utilized so that relatively small variations in power source voltage do not affect the operating point of the circuit.

Abstract: An improved safety device comprises a plurality of checking lights connected with the lamps of the automobile in series, a plurality of indicating lights adapted to an amplifier circuit and a magnetic induction coil, in which, the brightening or extinguishing of the checking lights may be shown to correspond to the extinguishing or brightening of the lamps of the automobile, so that the drivers can easily judge which one of the lamps is damaged.

Abstract: A charging circuit for charging a low voltage battery from an AC supply, said circuit comprising a full wave bridge rectifier, each leg of the bridge including a rectifying element, and means for providing a visual indication of normal operation of said charging circuit, wherein one of said rectifying elements is a light emitting diode to serve as said means for providing a visual indication.

Abstract: A system for monitoring the operability of warning lamps which provide a visual signal in the event of the malfunction or unacceptable variation of a monitored function or control comprising a plurality of optical indicators or warning lamps electrically coupled to a single-control switch common to all warning lamps such that all lamps may be simultaneously illuminated upon the closing of the switch to determine their operability.

Abstract: A glow lamp for indicating charged readiness of a flash apparatus is provided with a predetermined burning voltage corresponding to a specific charge voltage of the storage capacitor for the flash circuit, and the ignition voltage for the glow lamp is applied as periodic ignition pulses derived from voltage pulses occurring on periodic switching of the converter. The result is a more accurate response of the glow lamp to the desired charge value of the storage capacitor than is obtained by using the ignition voltage of the glow lamp as a threshold value.

Abstract: In an electronic flash device, wherein electrical energy stored by a main capacitor and an electronic flash tube is fired by the stored energy, a relaxation oscillator is adapted to oscillate when the main capacitor is charged to a given voltage level, which is a condition for completion of preparation for flash tube operation. The relaxation oscillator includes a capacitor, a glow discharge tube, and a resistor and the oscillation thereof causes intermittent glow discharge through the glow discharge tube for indicating the completion of preparation for flash tube operation. The electronic flash tube is triggered to emit a light flash by the stored energy of the relaxation oscillator capacitor. Excitation of the flash device, even with a power supply switch open, is prevented by isolating the main capacitor from the trigger capacitor and also from the glow discharge tube to also prevent an indication of flash preparation.