Abstract: A driving method for a light source apparatus for a projector using a single plate, comprises a step of supplying lamp current at a predetermined frequency to an extra-high pressure mercury lamp, a step of reversing a polarity of the lamp current to be supplied to the extra-high pressure mercury lamp, when one of boundaries between color areas of the color wheel is located at a light condensing area, and a step of supplying a low frequency current to the extra-high pressure mercury lamp at predetermined intervals, wherein the low frequency current starts to be supplied when a boundary from which a color area is changed to a predetermined color area is located at the light condensing area, and wherein the low frequency current continues to be supplied for a duration corresponding to the integer number of color areas of the color wheel.

Abstract: A driving method for a light source apparatus for a projector using a single plate, comprises a step of supplying lamp current at a predetermined frequency to an extra-high pressure mercury lamp, a step of reversing a polarity of the lamp current to be supplied to the extra-high pressure mercury lamp, when one of boundaries between color areas of the color wheel is located at a light condensing area, and a step of supplying a low frequency current to the extra-high pressure mercury lamp at predetermined intervals, wherein the low frequency current starts to be supplied when a boundary from which a color area is changed to a predetermined color area is located at the light condensing area, and wherein the low frequency current continues to be supplied for a duration corresponding to the integer number of color areas of the color wheel.

Abstract: A high pressure discharge lamp lighting apparatus comprises a high pressure discharge lamp including a discharge container made of quartz glass in which mercury and halogen is enclosed, and a first and second electrodes in which the first electrode is larger than the second electrode in size and face each other, a power supply section which turns on the discharge lamp by impressing a voltage of opposite polarity by turns between the pair of electrodes of the high pressure discharge lamp. In the lamp lighting apparatus, a control is carried out by the power supply section, so that a first period during which a positive voltage is impressed to the first electrode is longer than a second period during a positive voltage is impressed to the second electrode.

Abstract: To shorten the luminous flux rise time and prevent melting/deformation of the projections in the initial ignition period of high pressure discharge lamps that have a sealed mercury volume of no less than 0.20 mg/mm3, a power supply device feeds a current that exceeds the maximum current value of the constant power control period to the high pressure discharge lamp during a first control period from the initial discharge until the lamp voltage reaches a specified lamp voltage and causes a switch to constant power control, and then, during the following period until a change to steady power control, the power supply device feeds it a current that is less than the maximum current during regular operation.

Abstract: To shorten the luminous flux rise time and prevent melting/deformation of the projections in the initial ignition period of high pressure discharge lamps that have a sealed mercury volume of no less than 0.20 mg/mm3, a power supply device feeds a current that exceeds the maximum current value of the constant power control period to the high pressure discharge lamp during a first control period from the initial discharge until the lamp voltage reaches a specified lamp voltage and causes a switch to constant power control, and then, during the following period until a change to steady power control, the power supply device feeds it a current that is less than the maximum current during regular operation.

Abstract: A high pressure discharge lamp lighting apparatus comprises a high pressure discharge lamp including a discharge container made of quartz glass in which mercury and halogen is enclosed, and a first and second electrodes in which the first electrode is larger than the second electrode in size and face each other, a power supply section which turns on the discharge lamp by impressing a voltage of opposite polarity by turns between the pair of electrodes of the high pressure discharge lamp. In the lamp lighting apparatus, a control is carried out by the power supply section, so that a first period during which a positive voltage is impressed to the first electrode is longer than a second period during a positive voltage is impressed to the second electrode.

Abstract: To positionally stabilize the arc spot in a super-high pressure discharge lamp which is filled with at least 0.20 mg/mm3 of mercury and to prevent the formation of so-called flicker, in an operation device having a high pressure discharge lamp and a feed device, the feed device of the high pressure discharge lamp supplies a frequency in the range from 60 Hz to 1000 Hz as the stationary operating frequency and a low frequency, in a frequency range of from 5 Hz to 200 Hz is inserted which has an inserted length of from one half period to five periods, and an inserting period of from 0.01 seconds to 120 seconds, into the alternating current of the stationary operating frequency. Furthermore, the parameters of the low frequency are changed according to changes of the operating voltage of the discharge lamp.

Abstract: To positionally stabilize the arc spot in a super-high pressure discharge lamp which is filled with at least 0.20 mg/mm3 of mercury and to prevent the formation of so-called flicker, in an operation device having a high pressure discharge lamp and a feed device, the feed device of the high pressure discharge lamp supplies a frequency in the range from 60 Hz to 1000 Hz as the stationary operating frequency and a low frequency, in a frequency range of from 5 Hz to 200 Hz is inserted which has an inserted length of from one half period to five periods, and an inserting period of from 0.01 seconds to 120 seconds, into the alternating current of the stationary operating frequency. Furthermore, the parameters of the low frequency are changed according to changes of the operating voltage of the discharge lamp.

Abstract: In a discharge lamp which has a silica glass discharge vessel with an arc tube portion and hermetically sealed portions in which in the hermetically sealed portions of this discharge vessel metal foils are installed and hermetically sealed areas are formed, in accordance with the invention has a high endurance of the sealing action in the hermetically sealed areas and thus a long service life is obtained by a coating layer being formed on at least one side of the respective metal foil. The coating layer is formed from at least one metal oxide which is selected from titanium oxide, lanthanum oxide, tantalum oxide, zirconium dioxide which can contain yttrium oxide, and from hafnium dioxide which can contain yttrium oxide. Furthermore, the metal oxide which forms the coating layer is advantageously crystalline, and moreover, can be formed over a base layer which is made of aluminum oxide or yttrium oxide.

Abstract: A lamp seal (10, 30) of functionally gradient seal material and a lead bar (13, 32) that is fixed to the seal piece (11, 31), which seal piece is formed an inorganic layer with insulative properties and a number of mixed layers that are each mixtures of conductive inorganic materials and insulative inorganic materials, such that the proportion of conductive inorganic materials increases gradually in the direction of layering. A hole is formed extending in the direction of layering such that the lead bar can be fixed into the seal material with a sleeve-shaped metallic part made of a high-melting-point metal separating the outer periphery of the lead bar from the seal material. A lamp made with an air-tight seal formed of that lamp seal of functionally gradient material.

Abstract: In a discharge lamp which has a silica glass discharge vessel with an arc tube portion and hermetically sealed portions in which in the hermetically sealed portions of this discharge vessel metal foils are installed and hermetically sealed areas are formed, in accordance with the invention has a high endurance of the sealing action in the hermetically sealed areas and thus a long service life is obtained by a coating layer being formed on at least one side of the respective metal foil. The coating layer is formed from at least one metal oxide which is selected from titanium oxide, lanthanum oxide, tantalum oxide, zirconium dioxide which can contain yttrium oxide, and from hafnium dioxide which can contain yttrium oxide. Furthermore, the metal oxide which forms the coating layer is advantageously crystalline, and moreover, can be formed over a base layer which is made of aluminum oxide or yttrium oxide.