Intrinsically safe NDIR gas sensor in a can

A Non-Dispersive Infrared (“NDIR”) gas sensor for detecting the presence of a chosen gas, comprising:

• a mechanical housing comprising:
• a can having at least one inner reflective surface, a first window and a second window formed in the can;
• a header housing hermetically sealed to the can;
• a sample chamber affixed to the can;
• and
• an electronics module mounted on a printed circuit board contained within the can, said electronics module comprising:
• a Microelectronic Mechanical System (“MEMS”) source;
• a reference detector that produces a reference output;
• a signal detector that produces a signal output;
• and
• a microprocessor that receives the reference output and the signal output;
• wherein each of the reference detector and the signal detector have an identical narrow band pass filter with the same Center Wavelength (“CWL”), Full Width Half Maximum (FWHM) and transmittance efficiency at the CWL;
• and
• wherein the reference detector and the signal detector are mounted in the electronics module so that the at least one inner reflective surface and the sample chamber create a signal channel path length detected by the signal detector that is greater than a reference channel path length detected by the reference detector.

A Non-Dispersive Infrared (“NDIR”) gas sensor for detecting the presence of a chosen gas, comprising:

• a mechanical housing comprising a can and a header housing hermetically seated to the can;
• an electronics module mounted within the mechanical housing, said electronics module comprising:
• an infrared source;
• a reference detector that produces a reference output;
• a signal detector that produces a signal output;
• and
• a microprocessor that receives the reference output and the signal output;
• a sample chamber attached to the mechanical housing;
• and
• a first and a second window formed in the mechanical housing to allow radiation from the infrared source to enter into and return from the sample chamber;
• wherein each of the reference detector and the signal detector have an identical narrow band pass filter with the same Center Wavelength (“CWL”), Full Width Half Maximum (FWHM) and transmittance efficiency at the CWL;
• and
• wherein the reference detector and the signal detector are mounted in the electronics module so that the sample chamber creates a signal channel path length detected by the signal detector that is greater than a reference channel path length detected by the reference detector.