Low laser signal is usually responsible, and the cause can be: laser's drifting mechanical alignment, aging laser tube or HV power supply, or even humidity-damaged KBr in the windows or beamsplitter. These old FTIR units employ an actual HeNe laser tube as their interferometer. FTIR “not scanning” or “alignment failed” is a common failure and in most cases is due to a dead laser, provided the optics and electronics are fully functional. Potassium Bromide (KBR) is. The set up is either: Camera lens - beam splitter - camera x2 Or, Beam splitter - (lens + camera) x2 I want to be able to take 2x photos at once, so the light has to go through the beam splitter. I am not getting a usable image and would hugely appreciate some help. Additionally, beamsplitters can be used in reverse to combine two different beams into a single one. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux).
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