| 摘要 |
<p>The invention concerns a non-dispersive single beam detection assembly in an infrared gas analyzer. The detection assembly comprises radiation source(s) (1; 16, 21) providing infrared radiation, a measuring chamber (3), and a physical beam splitter (14) for dividing said radiation beam (11) into a reflected beam portion (13) and a transmitted beam portion (12), or for combining a reflected beam portion (18) and a transmitted beam portion (23) into said radiation beam (19). A measuring detector (6) receives one beam portions, and a reference detector (7) receives another beam portion. Alternatively a measuring/reference detector (20) receives both beam portions. Said transmitted beam portion (12, 23) has a first spectral intensity peak (NB1) at shorter wavelengths with a first peak wavelength (»1), and said reflected beam portion (13, 18) has a second spectral intensity peak (NB2) at longer wavelengths with a second peak wavelength (»2). There is a wavelength gap (G) between said second peak wavelength (»2) and said first peak wavelength (»1), which gap corresponds a wavelength shift (T) of an optical interference filter with said second peak wavelength (»2) as tilted from its perpendicular position to an angled position. Said wavelength gap (G) is at maximum 10% of the second peak wavelength (»2), and at minimum 0.5% of the second peak wavelength (»2).</p> |
