Metal halide discharge lamp suitable for an optical light source having a bromine to halogen ratio of 60-90%, a wall load substantially greater than 40 W/cm.sup.2, and a D.C. potential between the anode and cathode

An optical light source comprising:

• a metal halide discharge lamp including a quartz arc tube,
• said quartz arc tube having a pair of electrodes disposed within said tube, said electrodes comprising an anode electrode add a cathode electrode separated from each other by a predetermined distance and said anode electrode having a larger diameter than said cathode electrode, wherein a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2, and means for providing a D.C. potential between said anode and cathode electrodes from an external power source therethrough,
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including metal bromine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90%;
• and
• a reflector having a predetermined focal length and means capable of being connected to said external power source, wherein said metal halide discharge lamp is positioned within said reflector so as to be approximately disposed near said focal length of said reflector.

A color display device having a metal halide discharge lamp as an optical light source including red, green and blue light components for projecting a color image on a screen comprising,

• means for optically filtering the red, green and blue light components,
• means for modulating each of the light components with an image signal and producing modulated signals, and
• means for optically synthesizing the modulated signals,
• wherein said metal halide discharge lamp includes a quartz arc tube,
• said quartz arc tube having a pair of electrodes disposed within said tube, said electrodes having an anode electrode and a cathode electrode separated from each other by a predetermined distance and said anode electrode having a larger diameter than said cathode electrode;
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including metal bromine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90% and a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2 ;
• and
• means for providing a D.C. potential between said anode and cathode electrodes from an external power source therethrough.

An optical light source comprising:

• a metal halide discharge lamp including a quartz arc tube,
• said quartz arc tube having a pair of electrodes disposed within said tube, said electrodes comprising an anode electrode and a cathode electrode separated from each other by a distance less than 15 mm, wherein a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2, and means for providing a D.C. potential between said anode and cathode electrodes from an external power source therethrough,
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including metal bromine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90%;
• and
• a reflector having a predetermined focal length and means capable of being connected to said external power source, wherein said metal halide discharge lamp is positioned within said reflector so as to be approximately disposed near said focal length of said reflector and horizontally positioned within said reflector so that said anode and cathode electrodes substantially coincide with a horizontal axis of said reflector, said cathode electrode is substantially located near said focal length, whereby a light spot generated in said quartz arc tube is substantially positioned near said focal length.

A metal halide discharge lamp suitable for an optical light source comprising:

• a quartz arc tube;
• a pair of electrodes disposed within said tube, said electrodes comprising an anode electrode and a cathode electrode separated from each other by a predetermined distance, wherein a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2 ;
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including at least metal bromine and metal iodine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90% and the atomic percent of iodine to halogen other than bromine contained in said quartz arc tube is more than 90%;
• said metal bromine including at least one metal bromine selected from the group consisting of dysprosium bromine, tin bromine, indium bromine and thallium bromine, and said metal iodine including at least one metal iodine selected from the group consisting of dysprosium iodine, cesium iodine and neodymium iodine;
• and
• means for providing a D.C. potential between said anode and cathode electrodes.

An optical light source comprising:

• a metal halide discharge lamp including a quartz arc tube,
• said quartz arc tube having a pair of electrodes disposed within said tube, said electrodes comprising an anode electrode and a cathode electrode separated from each other by a predetermined distance, wherein a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2, and means for providing a D.C. potential between said anode and cathode electrodes from an external power source therethrough,
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including at least metal bromine and metal iodine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90% and the atomic percent of iodine to halogen other than bromine contained in said quartz arc tube is more than 90%;
• said metal bromine including at least one metal bromine selected from the group consisting of dysprosium bromine, tin bromine, indium bromine and thallium bromine, and said metal iodine including at least one metal iodine selected from the group consisting of dysprosium iodine, cesium iodine and neodymium iodine;
• and
• a reflector having a predetermined focal length and means capable of being connected to said external power source, wherein said metal halide discharge lamp is positioned within said reflector so as to be approximately disposed near said focal length, and horizontally positioned within said reflector so that said anode and cathode electrodes substantially coincide with a horizontal axis of said reflector.

A color display device having a metal halide discharge lamp as an optical light source including red, green, and blue light components for projecting a color image on a screen comprising:

• means for optically filtering the red, green, and blue light components;
• means for modulating each of the light components with an image signal and producing modulated signals;
• and
• means for optically synthesizing the modulated signals,
• wherein said metal halide discharge lamp includes;
• a quartz arc tubed
• a pair of electrodes disposed within said tube, said electrodes comprising an anode electrode and a cathode electrode separated from each other by a predetermined distance, wherein a wall load developed in said quartz arc tube is substantially greater than 40 W/cm.sup.2,
• said quartz arc tube containing an inert gas, mercury and a metal halide fill including at least metal bromine and metal iodine, wherein the atomic percent of bromine to halogen contained in said quartz arc tube is about 60% to 90% and the atomic percent of iodine to halogen other than bromine contained in said quartz arc tube is more than 90%,
• said metal bromine including at least one metal bromine selected from the group consisting of dysprosium bromine, tin bromine, indium bromine and thallium bromine, and said metal iodine including at least one metal iodine selected from the group consisting of dysprosium iodine, cesium iodine and neodymium iodine, and
• means for providing a D.C. potential between said anode and cathode electrodes from an external power source therethrough.