Abstract: An on-off switch and a dimmer for an electrical load such as an electric light. The on-off switch comprises a source and detector of infra-red radiation for controlling on-off circuitry and a load switch. The on-off switch is activated by passing one's hand close to and in front of the source and detector. This action activates the on-off circuitry to control the load switch to turn the light on. A second pass of the hand turns the light off. A second source and detector of infra-red radiation and dimmer circuitry are provided for dimming purposes. Dimming action is achieved by placing one's hand close to and in front of the second source and detector to activate the dimmer circuitry to sequentially control the load switch to change the brightness level of the light. The dimming sequence is stopped when the desired brightness level is reached by moving the hand away from the second source and detector.

Abstract: An energy-conserving solid-state-controlled illumination system which operates high-intensity-discharge lamps. The system operates the lamps at about a predetermined rated power consumption with a relatively high light output for a predetermined initial period of time during the initial night when a high degree of illumination is most needed. The system then operates the lamps for a later period of the night at a reduced power for a second predetermined period of time when a lower degree of illumination can be tolerated. Then if the lamps are still energized according to seasonal variations, the system thereafter operates the lamps at the relatively high light output for the remainder of the night to accommodate early morning traffic.

Abstract: A smoke alarm activated portable light or lamp for providing emergency illumination in response to an alarm signal from a smoke alarm device includes a frequency selective microphone, several amplifier stages, a peak detector, an isolation or buffer stage, and a power stage comprising a pair of cascaded transistors and a light bulb. The lamp includes a bracket for positioning same in proximity to a smoke alarm and a switch which is closed upon removal of the lamp from the bracket. A power saving circuit includes a photoelectric cell and an amplifier and is operative to saturate or overdrive the first gain stage to override any signal from the microphone whereby the lamp is rendered unresponsive to the smoke alarm signal upon illumination of the photocell by daylight or artificial light.

Abstract: There is disclosed an automatic light system for a moving vehicle wherein there is provided an on/off control feature responsive to ambient light conditions and responsive to the activation of windshield wipers. Included in the on/off control feature is electronics for a built in delay to delay changes in the on/off condition of the headlights caused by sudden or gradual darkness, sudden or gradual light, and the starting of the vehicle. The automatic light system includes a high/low beam control feature which is responsive to oncoming or passing cars.

Abstract: In an area illuminated by both artificial and natural light sources, a control system is implemented to reduce the energy consumption by proportionately dimming the artificial sources to a level such that the sum of natural plus artificial light is held essentially constant. Use of an open loop sensing scheme allows the control system to operate over a wide range of conditions with no oscillations and good control of the total illumination level.

Abstract: A lighting device in which an amount of light emitted by a lamp is detected by a light receiving element for controlling the input voltage of the lamp commensurate with the detected amount of light. By utilizing a pre-illumination system in conjunction with the lighting device, it is possible to improve the sensitivity characteristics of the light receiving element as the lamp is being charged up to a desired level of illuminescence and to prevent the input of an excessive voltage to the lamp.

Abstract: A lighting system for illuminating a given area is disclosed herein and includes a number of luminaires, each having a light source and a light sensitive device for automatically connecting the light source to a supply of power during the dark hours of the night and for automatically disconnecting the light source during the light hours of the day. This system also includes light control circuits associated with some but preferably not all of the luminaires. Each light control circuit overrides the operation of an associated light sensitive device and automatically disconnects its light source from the power supply for a predetermined period during the dark hours at a time when it is not important to provide a high degree of illumination, for example in the middle of the night.

Abstract: A lamp control circuit having a heater and thermistor coupled between the illumination sensitive device and the control electrode of an SCR or triac for providing a time delay between the detection of a change in illumination and the switching of the SCR or triac.

Abstract: A timing control circuit for use in automatically and intermittently operating electrical appliances, such as lamps, for security purposes in homes, offices and other buildings. The circuit is adapted to plug into a conventional wall socket and to receive conventional two-prong plugs of electrical appliances. When enabled, the circuit intermittently applies power from the wall socket to a connected electrical appliance so that the appliance is turned on and off automatically over some period of time. The circuit includes manually operable switches to enable a user to select the intermittency or on-off pattern of operation of the appliance and the period of time over which such pattern is developed. Controlling turn-on and turn-off of lamps, radios, or the like gives the appearance of occupancy of a dwelling and therefore discourages would be burglars and prowlers.

Abstract: An alternating current power source which is generally used to feed an ignition transformer primary winding may be electronically controlled so as to rapidly activate and deactivate the power source for each ignition cycle. An electronic switch intermittently interrupts current flowing in the primary winding and in the output circuit of the power source. Such electronic switch is made operable by virtue of the peak excursions of the alternating current, thus supplying the necessary collector potential to such switch during each firing cycle of the system. Such control system can have these type of controls in the collector circuit of the power source, the emitter circuit of such power source, the DC power input circuit for such power source, or in the output circuit of the power source's output transformer. A capacitor in series with the output circuit of the power source and with the primary winding enables current to be transferred out of the power source to such primary winding.

Abstract: A light emitting device which provides substantially constant output power is disclosed. The light emitting device includes a light emitter and a compensating circuit for supplying current to the light emitter so that at any given time an increase in electric current produces a corresponding increase in light intensity. The compensating circuit includes a following circuit for supplying current to the light emitter, a differential isolation amplifier for driving the following circuit and a light sensor and its related circuitry. The light sensor is in proximity to and substantially to the side of the light emitter and is connected in a feedback relationship to the differential isolation amplifier. In one arrangement, the compensating circuit is an integrated circuit, and the light emitter and compensating circuit are mounted on a header. The header forms a recess, and the light emitter is mounted on the header in the recess.

Abstract: A plurality of photodetectors in a single line exposed to a field of view transversely across the complete region of a glow discharge volume. The detectors are connected in an electronic circuit to trigger a crowbar device across the power supply circuit providing the voltage producing the discharge when any one detector receives an optical input substantially greater than normal, thereby preventing damage to the discharge electrodes due to arcing across the glow discharge.

Abstract: This invention relates to a circuit for lighting like a candlelight. The circuit has a lighting means having at least one incandescent lamp, and a control means which has a plurality of oscillators which can be oscillated with substantial equal frequencies. The control means controls an electric current flowing through the lighting means by a composite output of the oscillators. The each oscillator may be a relaxation oscillator which has a neon tube, and the control means may have a photo dependent resistor adapted to receive a composite light of lights emitted by the neon tubes, whereby the resistance of the photo dependent resistor being varied so as to control the electric current flowing through the lighting means.

Abstract: The disclosure is of a light-responsive electric switch which is characterized in that it is constituted mainly by a photoresistive cell inserted in a voltage-divider bridge of which the voltage variations, as functions of the illumination, control a standard integrated circuit comprising four NAND gates which, through the intermediary of a transistor, actuate a triac controlling the illumination circuit.

Abstract: A constant illumination level control system for continuously adjusting the evel of artificial illumination in an area of controlled lighting to complement available natural illumination. A photocell sensor in combination with an input amplifier generates a voltage representative of the illumination level in the area of controlled lighting. This illumination level voltage is compared by a comparator with a reference voltage, a non-zero difference voltage output from the comparator being indicative of a change in the illumination level from a desired, preset level. The output from the comparator is applied to a solid state dimmer circuit which, by controlling the gating of a triac, regulates the electrical energy input to the artificial lighting system. In response to a non-zero difference voltage output from the comparator, the solid state dimmer circuit, in combination with the triac, adjusts the artificial illumination output to reestablish the desired, preset level of total illumination.

Abstract: An automatic vehicle headlamp intensity adjustement circuit includes a high sensor. A tuned rectifier circuit for producing a d.c. signal of magnitude dependent on the amplitude of the 50Hz (or other local supply frequency) component of the signal picked up by the sensor. A lamp current modulating circuit is controlled by this d.c. signal through the intermediary of an averaging circuit. The averaging circuit has a relatively long time constant and a timer is connected to reduce this time constant if the d.c. signal continues to fall for more than a predetermined period of time.

Abstract: A circuit is provided including a reactor for operating a fluorescent lamp from AC line voltage and including a high frequency inverter for operating the lamp from a battery upon failure of line voltage. The inverter also serves to start the lamp during normal conditions, that is, when AC line voltage of sufficient value is available to the lamp.

Abstract: A digital light-sensing control system for use in light sensitive equipment, such as a digital watch or a camera, is comprised of light sensor means such as a photo resistor, a digital brightness detector, and brightness control logic. The light sensor means produces analog signals which vary with ambient light intensity. The digital brightness detector selectively digitizes the analog signals to generate digital brightness signals. The brightness control logic generates system control signals in response to the digital brightness signals. Several embodiments of the digital brightness detector and the brightness control logic are disclosed. Each embodiment is capable of being integrated on a single semiconductor substrate.

Abstract: Pulse operating circuit for high intensity gaseous discharge lamps is provided with improved lamp starting device. The circuit comprises a direct current supply, a transistor switch in series with a ballast inductor and a lamp across the DC supply, an SCR switch connected across the inductor, a control circuit connected to the transistor switch for applying DC pulses to the lamp at a predetermined repetition rate and duty cycle, a sensing circuit for sensing the voltage across the inductor, and a variable SCR firing control circuit connected to the SCR and the first mentioned control circuit and responsive to the sensing circuit to control the firing of the SCR for limiting the peak current through the transistor switch during the lamp starting and warm-up interval.

Abstract: A circuit is disclosed which is suitable for controlling lighting in a building from a multiple number of points. AC current to light bulbs is controlled by a triac which in turn is controlled by the output of an optical coupler which is controlled by the output of a logic device. The output of said logic device is connected to control the input to the triac. Switches connecting to the input of the logic device each can independently determine energization or deenergization of the light bulbs.

Abstract: The disclosed invention includes apparatus and method for full wave rectification of commerical alternating current of conventional or standard low frequency (e.g., 50-60 hz.) and for generating substantially square wave pulses of high frequency for transformation to voltage suitable for illumination of gas discharge lamps. The apparatus includes electronic means for rectification and silicone control rectifiers and stearing diodes, plus RC devices, for setting up a primary wave or pulse oscillation to produce a desired form of wave pulses at a suitable high frequency. Apparatus also includes variable potentiometer means for varying the lighting intensity by changing width or duty cycle of power pulses as applied to the primary of the light-operating transformer without substantially changing their frequency. Means which can be on or off also are included to periodically turn off the transformer power for "flashing" or periodic lighting and extinguishing of the lamps when such operation is needed.

Abstract: The light sensitive circuit which controls the voltage at the control electrode of the thyristor used to control the termination of the flash includes a photosensor and a resistor-capacitor integrator circuit connected to the photosensor. The voltage across the capacitor is applied to the control electrode of the thyristor. In accordance with the present invention, a diode connected in series with a variable resistor is connected in parallel with the resistor of the integrator circuit. An additional resistor may be connected in parallel with the capacitor and a further resistor in parallel with the whole integrator circuit in order to allow adjustment of the operating region of the diodes such that it has a very low resistance only when a very high quantity of light as reflected by a very close object impinges upon the photosensor.

Abstract: An improved photocontrol system for electrical lamps comprising the combination of photoelectric means responsive to the intensity of the ambient light for controlling the turning the lamps on and off, and an electronic timer for turning off the lamps at a preset time interval, after they have been turned on.

Abstract: Circuits and auxiliary elements for use with a device for controlling the emission of light pulses from a flash unit, which light pulses are produced by the discharge of current pulses from a capacitor, the device including a light sensing element for receiving light produced by the flash unit and reflected from an object in the light path. One such circuit includes two zener diodes for providing threshold voltages for use in comparing the output of the light sensing element. Another such circuit compensates for nonlinearities in the response of certain components of the device.