초록 ▼

An instrument for determining the concentration of a particular gas that might be present in a sample has no moving parts and is extremely compact. The instrument uses as a source of radiation a device that has a radiating element whose temperature is alternated between T1 and T2 and whose spectrum

An instrument for determining the concentration of a particular gas that might be present in a sample has no moving parts and is extremely compact. The instrument uses as a source of radiation a device that has a radiating element whose temperature is alternated between T1 and T2 and whose spectrum approximates that of a blackbody. Radiation from this source is passed through a dual pass band filter that has two non-overlapping pass bands, one of which is centered at a wavelength at which the gas absorbs and the other of which is centered at a wavelength at which the sample does not absorb radiation. After passing through this filter, the radiation passes through the sample chamber and then is intercepted by a detector which produces an electrical signal determined by the radiation intercepted. The electrical signal is processed to provide an indication of the concentration of the gas.

대표청구항 ▼

A gas analyzer for determining the concentration of a gas that is included in a sample, comprising in combination: a sample chamber containing the sample; differential temperature source means including a radiating element and including means for altering the temperature of said radiating element fr

A gas analyzer for determining the concentration of a gas that is included in a sample, comprising in combination: a sample chamber containing the sample; differential temperature source means including a radiating element and including means for altering the temperature of said radiating element from T1 to T2 and from T2 to T1 for producing radiation having a first spectrum when the temperature is T1 and having a second spectrum when the temperature is T2; dual pass band filter means located between the radiating element of said differential temperature source means and said sample chamber, and having two non-overlapping pass bands, one of which is centered at a wavelength at which the gas absorbs radiation and the other of which is centered at a wavelength at which the sample does not absorb radiation, for simultaneously passing radiation within the two nonoverlapping pass bands; detector means for intercepting radiation that has passed through said dual pass band filter means and through said sample chamber and for converting the intercepted radiation to an electrical signal; and, circuit means electrically connected to said detector means for processing the electrical signal to determine the concentration of the gas; said sample chamber, said differential temperature source means, said dual pass band filter means, said detector means, and said circuit means all remaining stationary when the gas analyzer is in use.