Abstract: The purpose of the present invention is to provide a semiconductor light-emitting device having good life characteristics and higher light extraction efficiency than conventional devices. This semiconductor light-emitting device includes a substrate; semiconductor layers including a first semiconductor layer, an active layer, and a second semiconductor layer; a first electrode; and a second electrode. The opposite surface of the first semiconductor layer from the active layer comprises a smooth surface portion and a roughened surface portion, the smooth surface portion is provided in a region where the first electrode is formed, the roughened surface portion is provided at least in a part of a region where the first electrode is not formed, and the second semiconductor layer and the second electrode are in contact with each other at a position outside an outer edge of the first electrode.

Abstract: An operating circuit for a discharge lamp having an external auxiliary electrode and main discharge electrodes in a discharge space, in which the disadvantage of lamp damage due to detachment of glass material, such as silica glass or the like, of a hermetically sealed portion of the discharge vessel from the electrode material in alternating current operation of a discharge lamp is prevented by a feed circuit having an inverter, and a trigger circuit for supply of a pulsed current to the primary winding of a high voltage transformer with an autotransformer arrangement for applying a high voltage to the auxiliary electrode in which the electrical potential of the trigger terminals is maintained essentially at the same electrical potential as the output line on the low voltage side of the feed circuit when the trigger circuit is inoperative.

Abstract: An operating circuit for a discharge lamp having an external auxiliary electrode and main discharge electrodes in a discharge space, in which the disadvantage of lamp damage due to detachment of glass material, such as silica glass or the like, of a hermetically sealed portion of the discharge vessel from the electrode material in alternating current operation of a discharge lamp is prevented by a feed circuit having an inverter, and a trigger circuit for supply of a pulsed current to the primary winding of a high voltage transformer with an autotransformer arrangement for applying a high voltage to the auxiliary electrode in which the electrical potential of the trigger terminals is maintained essentially at the same electrical potential as the output line on the low voltage side of the feed circuit when the trigger circuit is inoperative.

Abstract: To devise an ultrahigh pressure mercury lamp in which the disadvantages of formation of blackening and of cracks in the arc tube are reliably prevented, and it is possible even during operation over a long time to keep a high degree of maintenance of illuminance and reliability, the ultrahigh pressure mercury lamp has a pair of electrodes in the arc tube which is filled with at least 0.15 mg/mm3 of mercury and the electrodes have a carbon content that is at most 10 ppm by weight and an oxygen content that also is at most 10 ppm by weight.

Abstract: An ultra-high pressure discharge lamp in which the disadvantage of the reduction of the illuminance maintenance factor due to formation of blackening and milky opacification in the discharge vessel and the disadvantage of formation of cracks in the discharge vessel is eliminated by the discharge vessel being made of a silica glass that contains 0.1 ppm by weight to 290 ppm by weight hydrogen. Further advantages are obtained by the silica glass having a content of OH radicals that is at most 1 ppm by weight and a content of aluminum in a range of 2 ppm by weight to 30 ppm by weight.

Abstract: An ultra-high pressure mercury lamp in which both devitrification and also breakage of the discharge vessel can be eliminated. In the ultra-high pressure mercury lamp, there is a pair of opposed electrodes in a fused silica glass discharge vessel filled at least 0.15 mg/mm3 mercury, and an alkali metal concentration in the area from the inside surface of this discharge vessel to a depth of 4 microns that is at most 10 wt. ppm.

Abstract: An ultra-high pressure discharge lamp in which the disadvantage of the reduction of the illuminance maintenance factor due to formation of blackening and milky opacification in the discharge vessel and the disadvantage of formation of cracks in the discharge vessel is eliminated by the discharge vessel being made of a silica glass that contains 0.1 ppm by weight to 290 ppm by weight hydrogen. Further advantages are obtained by the silica glass having a content of OH radicals that is at most 1 ppm by weight and a content of aluminum in a range of 2 ppm by weight to 30 ppm by weight.

Abstract: The present invention is a short arc type ultra-high pressure discharge lamp in which a pair of electrodes 3 are disposed inside an arc tube 1 that comprises quartz glass, seal portions 2 are formed that comprise quartz glass and extend to both sides of the arc tube 1, and at least 0.15 mg/mm3 of mercury is filled into the arc tube 1, wherein a metal foil 4 is embedded in each of the seal portions 2, and metal granular lumps 6 are protrusively provided on surfaces of each metal foil 4.

Abstract: A high pressure mercury lamp for a projector device in which a discharge vessel made of quartz glass is filled with at least 0.15 mg/mm3 mercury in which both devitrification of as well as damage to the discharge vessel can be eliminated is obtained by the quartz glass of the discharge vessel being given a fictive temperature of 1000° C. to 1250° C., a total content of alkali metals of 0.1 ppm by weight to 3 ppm by weight and an aluminum content of from 1 ppm by weight to 30 ppm by weight.

Abstract: An ultra-high pressure mercury lamp in which both devitrification and also breakage of the discharge vessel can be eliminated. In the ultra-high pressure mercury lamp, there is a pair of opposed electrodes in a fused silica glass discharge vessel filled at least 0.15 mg/mm3 mercury, and an alkali metal concentration in the area from the inside surface of this discharge vessel to a depth of 4 microns that is at most 10 wt.ppm.

Abstract: The present invention is a short arc type ultra-high pressure discharge lamp in which a pair of electrodes 3 are disposed inside an arc tube 1 that comprises quartz glass, seal portions 2 are formed that comprise quartz glass and extend to both sides of the arc tube 1, and at least 0.15 mg/mm3 of mercury is filled into the arc tube 1, wherein a metal foil 4 is embedded in each of the seal portions 2, and metal granular lumps 6 are protrusively provided on surfaces of each metal foil 4.

Abstract: A high pressure mercury lamp for a projector device in which a discharge vessel made of quartz glass is filled with at least 0.15 mg/mm3 mercury in which both devitrification of as well as damage to the discharge vessel can be eliminated is obtained by the quartz glass of the discharge vessel being given a fictive temperature of 1000° C. to 1250° C., a total content of alkali metals of 0.1 ppm by weight to 3 ppm by weight and an aluminum content of from 1 ppm by weight to 30 ppm by weight.

Abstract: The bulldozer blade control mechanism according to the present invention has a U-shaped frame (22) fixed to the lower intermediate portion of the rear surface of a blade (20) so that the frame (22) can be turned in all directions, left and right lifting and angling hydraulic cylinders (62, 64) respectively fixed pivotably to between the left and right portions of the rear surface of the blade and the left and right portions of a chassis via arms (36, 38), left and right pitching and tilting hydraulic cylinders (40, 42) respectively fixed pivotably to between those portions of the arms (36, 38) which are in the vicinity of the rear ends thereof and the left and right upper portions of the rear surface of the blade, and left and right levers (56, 58) respectively fixed pivotably to between the left and right parallel leg portions of the U-shaped frame (22) and either of left and right hydraulic cylinders (62, 64) and left and right arms (36, 38).