Abstract: An emitting source capable of radiating substantial energy in the near infrared spectrum and suitable for use in non-dispersive infrared gas analyzers or other devices is described. Operation can be steady state (DC) or pulsed at high frequency with excellent modulation characteristics. The device consists of a tungsten filament mounted across the pins of a small transistor outline header and centered at the focal point of a parabolic or other shaped reflector. The header assembly is enclosed by a resistance-welded cap and window assembly having a specially sealed sapphire or other suitable IR transmissive window. Fundamental to the operation of the inventive IR emitter is the incorporation of a getter within the header package configured to prevent oxidation degradation of the tungsten filament. An inert gas backfill limits filament evaporation and further extends apparatus lifetime.

Abstract: An emitting source capable of radiating substantial energy in the near infrared spectrum and suitable for use in non-dispersive infrared gas analyzers or other devices is described. Operation can be steady state (DC) or pulsed at high frequency with excellent modulation characteristics. The device consists of a tungsten filament mounted across the pins of a small transistor outline header and centered at the focal point of a parabolic or other shaped reflector. The header assembly is enclosed by a resistance-welded cap and window assembly having a specially sealed sapphire or other suitable IR transmissive window. Fundamental to the operation of the inventive IR emitter is the incorporation of a getter within the header package configured to prevent oxidation degradation of the tungsten filament. An inert gas backfill limits filament evaporation and further extends apparatus lifetime.

Abstract: A pulsable infrared radiation (IR) source which can be used in nondispersive infrared gas analyzers. The pulsable IR source includes a narrow strip of thin metallic foil vertically mounted to the opposite sides of pins of a small transistor type (TO-5) header at the base of a large diameter deep reflector. Infrared radiation from both sides of the heated foil is directly reflected to form a highly efficient source. The foil can be oxidized or otherwise coated under controlled conditions to maximize its emissivity at operating temperatures up to approximately 1200 degrees K. The package is resistance welded with a cap and hermetically sealed window of a suitable material and filter as required to transmit the desired infrared spectrum. An appropriate inert backfill gas prevents further oxidation and enhances the pulsing capability.