Examples disclosed herein relate to a to a pitch gradient in a lamp filament, and a method of making. In one implementation, a lamp has a bulb filled with a gas. A filament is disposed within the bulb. The filament has a plurality of coils that include a first coil having a first point. The plurality of coils includes a second coil having a second point, and a third coil having a third point. The pitch gradient is defined by a first pitch between the second point and the first point, and a second pitch between the third point and the second point. The second pitch is greater than the first pitch. The second point is 360 degrees away from the first point. The third point is 360 degrees from the second point. A terminal coil is electrically coupled to at least the first coil, the second coil, and the third coil.

Examples disclosed herein relate to a to a pitch gradient in a lamp filament, and a method of making. In one implementation, a lamp has a bulb filled with a gas. A filament is disposed within the bulb. The filament has a plurality of coils that include a first coil having a first point. The plurality of coils includes a second coil having a second point, and a third coil having a third point. The pitch gradient is defined by a first pitch between the second point and the first point, and a second pitch between the third point and the second point. The second pitch is greater than the first pitch. The second point is 360 degrees away from the first point. The third point is 360 degrees from the second point. A terminal coil is electrically coupled to at least the first coil, the second coil, and the third coil.

A method, executed by a computer, includes receiving extent information for a light zone and a desired emitted light level for a light source proximate to the light zone where the light source is a programmable light source, determining that the light source projects light onto the light zone, and adjusting, by one or more processors, the light source to emit the desired emitted light level. A computer system and a computer program product corresponding to the method area also disclosed herein.

A tungsten-halogen electromagnetic radiation source has a sealed transparent aluminum oxynitride envelope defining an interior volume. At least one optical element is integrally formed into the aluminum oxynitride envelope. A tungsten filament is located in the aluminum oxynitride envelope. A fill gas in the interior volume contains at least a gaseous halogen compound.

A tungsten-halogen electromagnetic radiation source has a sealed transparent aluminum oxynitride envelope defining an interior volume. At least one optical element is integrally formed into the aluminum oxynitride envelope. A tungsten filament is located in the aluminum oxynitride envelope. A fill gas in the interior volume contains at least a gaseous halogen compound.

A lamp assembly for the lamp assembly adapted for use in a substrate thermal processing chamber to heat the substrate to temperatures up to at least about 1100 C. is disclosed. In one embodiment, the lamp assembly comprises a bulb enclosing at least one radiation generating filament attached to a pair of leads, the bulb having an inner surface and an outer surface, a lamp base configured to receive the pair of leads and at least a portion of the bulb having a surface treatment adapted to reflect light away from the lamp base. In another embodiment, a sleeve covers the lamp base, which has a cross-sectional area less than about 1.2 times the cross-sectional area of the bulb.

A lamp assembly for the lamp assembly adapted for use in a substrate thermal processing chamber to heat the substrate to temperatures up to at least about 1100 C. is disclosed. In one embodiment, the lamp assembly comprises a bulb enclosing at least one radiation generating filament attached to a pair of leads, the bulb having an inner surface and an outer surface, a lamp base configured to receive the pair of leads and at least a portion of the bulb having a surface treatment adapted to reflect light away from the lamp base. In another embodiment, a sleeve covers the lamp base, which has a cross-sectional area less than about 1.2 times the cross-sectional area of the bulb.