摘要:
A metal halide lamp has a ceramic discharge vessel with an inside length L, an inside diameter D, and an aspect ratio L/D of between 3 and 5. The fill gas includes xenon, mercury, sodium halide, and halides of rare earth metals. Hydrogen iodide voltage spikes during start-up are related to product of volume and the cold xenon pressure, which are adjusted to limit the spikes. Voltage crest factor is related to the product of total operating pressure and the square of the inside diameter, which are adjusted to limit the crest factor. The ceramic discharge metal halide (CDM)lamp may have a power rating of 200 W or more and can be used with an existing ballast for a high pressure sodium (HPS) lamp of like power rating.
摘要:
Discharge lamp includes a ceramic metal halide lamp having a central barrel enclosing a discharge space containing a fill gas and opposed end plugs which receive electrode lead-ins therethrough. A conductive ring is provided around each end plug, which is preferably polycrystalline alumina (PCA). These rings are connected by an antenna on the central barrel and thereby capacitively coupled to the lead-ins. The rings and the antenna are preferably sintered tungsten which is coated on the arc tube in paste form prior to sintering. When a voltage is applied across the electrodes, the resulting electric field causes the PCA to emit UV radiation which stimulates photoelectrons to initiate a discharge in the fill gas.
摘要:
The invention relates to a high-pressure discharge lamp of the ceramic metal halide type of the Philips MasterColor series having a molybdenum coil wrapped around the discharge vessel and at least a portion of the electrode feed through means, and having power ranges of about 150 W to about 1000 W. Such lamps are provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gastight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gastight connection. In addition, the lamps display one or more and most preferably all of the following properties: a CCT (correlated color temperature) of about 3800 to about 4500K, a CRI (color rendering index) of about 70 to about 95, a MPCD (mean perceptible color difference) of about ±10, and a luminous efficacy up to about 85-95 lumens/watt, a lumen maintenance of >80%, color temperature shift
摘要:
The invention relates to a high-pressure discharge lamp of the ceramic metal halide type of the Philips MasterColor® series having power ranges of about 150 W to about 1000 W. Such lamps are provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gas-tight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gas-tight connection. In addition, the lamps display one or more and most preferably all of the following properties: a CCT (correlated color temperature) of about 3800 to about 4500 K, a CRI (color rendering index) of about 70 to about 95, a MPCD (mean perceptible color difference) of about ±10, and a luminous efficacy up to about 85-95 lumens/watt, a lumen maintenance of >80%, color temperature shift
摘要:
The invention relates to a high-pressure discharge lamp of the ceramic metal halide type of the Philips MasterColor series having a molybdenum coil wrapped around the discharge vessel and at least a portion of the electrode feed through means, and having power ranges of about 150 W to about 1000 W. Such lamps are provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gastight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gastight connection. In addition, the lamps display one or more and most preferably all of the following properties: a CCT (correlated color temperature) of about 3800 to about 4500K, a CRI (color rendering index) of about 70 to about 95, a MPCD (mean perceptible color difference) of about ±10, and a luminous efficacy up to about 85-95 lumens/watt, a lumen maintenance of >80%, color temperature shift
摘要:
The invention relates to a high-pressure discharge lamp of the ceramic metal halide type of the Philips MasterColor® series having power ranges of about 150 W to about 1000 W. Such lamps are provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gas-tight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gas-tight connection. In addition, the lamps display one or more and most preferably all of the following properties: a CCT (correlated color temperature) of about 3800 to about 4500K, a CRI (color rendering index) of about 70 to about 95, a MPCD (mean perceptible color difference) of about ±10, and a luminous efficacy up to about 85-95 lumens/watt, a lumen maintenance of >80%, color temperature shift
摘要:
A high pressure gas discharge lamp includes first and second discharge devices electrically connected in series within an outer envelope. The discharge devices each include a discharge vessel enclosing a discharge space with an ionizable fill and first and second discharge electrode assemblies. The first discharge electrode assemblies of the discharge devices are connected so as to receive a starting pulse and lamp operating voltage. Each discharge vessel includes a first wall portion spaced from the first discharge electrode assembly and defining an ionizable gap therebetween. A conductive element bridges the discharge devices at the first wall portions and capacitively couples the first discharge electrode assemblies to induce ionization in one of the discharge devices in the ionizable gap between the first wall portion and first discharge electrode assembly.
摘要:
A method for characterising the surface profile of a component comprises the steps of a) dividing the surface into at least two regions; b) for each region, measuring the surface and selecting a number of measured points to define a co-ordinate dataset for the region; c) for each region, applying a curve-fitting algorithm to the dataset for the region to define the surface profile of the region; d) combining the defined surface profiles for the regions to produce a defined surface profile for the aerofoil surface. The characterisation may be used in the design, analysis and manufacturing steps of product development, thereby decreasing the total time and work required.
摘要:
HID lamp has a U-enhancer connected between first and second leads for an arc tube. The UV-enhancer has a quartz envelope containing an electrode connected to the first lead, and is surrounded by a metal ring which is spaced from the envelope by a sleeve of borosilicate glass. The ring is capacitively coupled to the envelope and is electrically connected to the second lead, which may also support the sleeve.