Abstract: A rapid start fluorescent lamp contains a circuit opening device on the cathode mount which opens a short time after lamp starting and stops heater current flow to the cathode. The circuit opening device is a thermostatic element in a sealed glass tube. Additional support is provided for the cathode end that is connected to the circuit opening device in order to prevent damage from vibration.

Abstract: A cathode ray tube control system comprising a cathode ray type tube having a tubular envelope wherein an electron gun is disposed to direct an electron beam onto a spaced anode target screen, the gun including an electron emitting source aligned with an adjustably biased grid means for controlling the current level of the electron beam, and external circuit means connected to the grid means and to the source for adjusting the current level of the electron beam and the electron emission capability of the source correspondingly.

Abstract: High pressure sodium vapor lamps containing sodium or both sodium and mercury are raised in color temperature and improved in color rendition by pulse operation. During the pulse there is considerable enhancement and broadening of the sodium lines at 449, 467, 498 and 568 nm and the development of a continuum from 400 to 450 nms, and also the appearance of visible mercury lines in lamps containing mercury. Optimum results with lamps in size ratings from 50 to 1000 watts are obtained with pulse repetition rates from 500 to 2000 Hz and duty cycles from 10 to 35%. The color temperature may be increased from the common value of 2050.degree. K to 2500.degree. K with reduction in lamp efficacy of only about 20% from conventional 60 Hz operation. Even higher color temperatures may be obtained if further reduction of efficacy is acceptable.

Abstract: Gaseous discharge lamps of high pressure sodium vapor type having an arc tube containing a mixture of sodium vapor and another metal vapor are operated with unidirectional current (DC) pulses in a manner to avoid color separation of the light due to segregation of the atoms of the different metal vapors. The DC pulses are applied to the lamp with repetition rates of from about 50 Hertz to about 23,000 Hertz and a duty cycle of from about 8% to about 80%.

Abstract: A lamp-starting device for use in a lamp socket adapted to receive the base of a lamp, the device having a pair of electrically-conductive plates disposed in spaced relation in and electrically insulated from each other by a housing of electrically insulating material. An electrical resistor is located between and electrically connects the plates, the resistor being in the circuit when the lamp is initially energized. A temperature-actuated mercury switch is located between the plates, the mercury switch being electrically connected to and located in heat transfer relation to the plate that is adapted to engage the lamp base. The mercury switch electrically interconnecting the plates when the mercury is heated by conductive heat from the lamp socket to bypass the resistor in the circuit after initial energization.

Abstract: A rapid start fluorescent lamp contains a circuit opening device on the cathode mount which opens a short time after lamp starting and stops heater current flow to the cathode.

Abstract: A field emission electron gun according to this invention comprises a cathode for emitting electrons, an anode, a high voltage source which applies a high voltage between the cathode and the anode in order to cause emission of electrons from the cathode, a reference voltage source, voltage control means for controlling and stabilizing the output voltage of the high voltage source in response to an output voltage of the reference voltage source, means for detecting the value of an emission current from the cathode, means for delivering as an output a signal corresponding to the difference between the detected value and a desired value, and means for applying the output signal to the reference voltage source through a switch.

Abstract: Protection against potentially destructive arcs which may occur within a gas-filled incandescent lamp when the energized filament fails is achieved by partly embedding separate inner and outer lead-in conductors in an hermetic seal that is formed on one end of the lamp envelope and electrically connecting the conductors by a short uncoiled fuse element that is located entirely within the confines of the envelope. In the case of a halogen-cycle type lamp having a press-sealed envelope, the fuse element comprises a tungsten wire which is preferably from about 1% to 10% larger in diameter than the filament wire and is fastened to the inner lead-in conductor at a point located inside the envelope, and to the outer lead-in conductor at a point which is located within the press seal. Reliable arc-suppression is thus achieved in a practical inexpensive manner with rugged components that are readily made integral parts of the finished lamp.

Abstract: An electron producing apparatus of the field emission type wherein instantaneous values of an emitted current are sequentially measured to store a relative minimum value of the emitted current which is obtained in such a manner that one instantaneous value which is stored is then replaced by another instantaneous value which is even smaller in magnitude than the previously stored one, and at the same time the instantaneous values are sequentially compared with the stored relative minimum value so that the electron producing apparatus is deenergized when an instantaneous value assumes a certain magnitude relative to the stored relative minimum value.

Abstract: In a method of operating a photochemotherapy chamber for the irradiation of a patient with long wave ultraviolet light, a prescribed dosage is first selected. The prescribed dosage is then automatically converted into the time duration that an ultraviolet source should be energized to deliver said dosage by monitoring the line voltage and the total hours of operation of the ultraviolet source and adjusting said time duration accordingly.

Abstract: Power supply turn-on and turn-off transients are eliminated in power supplies employing thermionic vacuum tube pass devices and control amplifiers for controlling the output voltage of the power supply by controlling the conductance of the pass tube or tubes. The elimination of turn-on transients is accomplished by cutting off the pass tube and rendering the control amplifier non-responsive for a predetermined time after the power supply is turned on. The turn-off transients are eliminated by quickly restoring the cut-off of the pass tube and the non-responsive rendering means of the control amplifier very quickly after the turn-off instant of the power supply.

Abstract: A device for operating a low-pressure sodium vapor discharge lamp without a ballast. The electrode voltage drop near a main electrode of the sodium lamp is influenced by a change in the pre-heating current of that electrode and/or a change in the effective area of the electrode. The changed electrode voltage drop thus obtained provides a mechanism whereby any changes in the lamp current are opposed so as to produce ballast-free lamp operation.

Abstract: System for the power control of high voltage electron beam generators having a cathode and a control electrode associated with the cathode. The system is provided with a high voltage isolation transformer with primary and secondary winding for supplying the control electrode with a control voltage. A system precedes the isolation transformer on the primary side and is adapted to generate square wave pulses susceptible of amplitude modulation. The pulse generator is designed such that the pulses are square wave impulses symmetrical with the null line. The isolation transformer is provided with a tertiary winding on the primary side and the primary winding receives input from an amplifier whose input is connected with the output voltage of the tertiary winding. A rectifier bridge is connected to the secondary winding.

Abstract: The inner arc tube of some jacketed discharge lamps transmits ultraviolet radiation which is normally intercepted by the glass outer envelope. To prevent harmful release of such radiation in the event the outer envelope should be shattered, a mechanical disconnect is provided in the interenvelope space comprising separable conductors which are part of the arc tube supporting frame and which are maintained in engagement by the outer envelope. Upon fracture of the outer envelope, spring pressure forces the conductors apart whereupon the circuit is opened and the arc tube is disabled.

Abstract: HID lamp has a spring-loaded safety switch positioned between the outer protective envelope and the arc tube and electrically connected in series with one of the lamp electrodes. When the lamp is operating normally, the safety switch is maintained in the closed position, but if the outer envelope is accidentally broken, the switch automatically opens to break the lamp energizing circuit and render the lamp inoperative.

Abstract: HID lamp has resilient safety switch positioned proximate the inner surface of the dome portion of the protective outer envelope in contact with an extremity of a resilient leaf-spring support portion of the arc tube frame, to maintain the switch in a closed position. When the envelope is shattered, the normally closed switch will open to break the electrical path to the arc tube, thereby rendering the lamp inoperative.

Abstract: A lamp-starting device for use in a lamp socket adapted to receive the base of a lamp, the device having a pair of electrically-conductive plates disposed in spaced relation in and electrically insulated from each other by a housing of electrically insulating material. An electrical resistor is located between and electrically connects the plates, the resistor being in the circuit when the lamp is initially energized. A temperature-responsive bimetal strip is located between the plates, the bimetal strip having a contact movable into engagement with a contact on one of the plates when the bimetal strip is heated by conductive heat from the resistor, lamp base and socket to by-pass the resistor in the circuit after initial energization, the bimetal strip being electrically connected to the other of the plates. The bimetal strip includes a loop disposed about the resistor and engaging the other plate and engaging an electrically-insulating member disposed between the plates.

Abstract: Ultraviolet light processors containing a plurality of ultraviolet light sources are improved by providing means for increasing the intensity of one lamp to compensate for a reduction in intensity of another lamp so that the total intensity of the system is substantially the same. If both lamps are located at the first foci of a conjugate reflector system, the intensity profile will be substantially reestablished.

Abstract: An electron gun comprising a changeover chamber and changeover circuit between the gun chamber and the insulated cable which connects the power supply circuits to the electrodes which enables adjustment of electrode potentials to accomplish electrode treatment without excessive gun currents.

Abstract: An improved field emission type electron gun is automatically controlled so as to generate a stable emission current. The preferred embodiment employs a detecting means for detecting the emission current fluctuation and a control means for controlling the electric field for field emission according to the output signal of said detecting means.

Abstract: circuit for controlling the electron discharge from a cathode, of an electron discharge device, which provides a control voltage signal, proportional to the cathode current, for comparison with a reference value to provide a correction bias to a grid interposed between the cathode and an anode.