On-line titration using colorimetric end point detection

An on-line colorimetric titration endpoint detection apparatus, comprising:

• a) means for directing radiant energy from a source into and through a chamber to an exit;
• b) first pathway means for conveying radiant energy to said means for directing radiant energy through said chamber;
• c) means for collecting said radiant energy exiting from said chamber;
• d) second pathway means for conveying radiant energy away from said chamber exit to a detector;
• e) means for generating a modulated first optical signal on said first pathway means;
• f) means for generating a modulated second optical signal on said first pathway means;
• g) means for detecting a colorimetric optical signal on said second pathway means;
• h) means for demodulating said first optical signal;
• i) means for demodulating said second optical signal;
• j) means for relating the first and second demodulated optical signals to a colorimetric endpoint,
• wherein said chamber is located in a titration vessel, and wherein said means for directing radiant energy into and through said chamber to said exit and said means for collecting radiant energy comprise partial surfaces of at least one interior conical reflecting surface.

In apparatus for on-line colorimetric titration endpoint detection of a fluid with a probe, including a titration vessel enclosing a chamber having an optical entry and an optical exit, the method comprising:

• a) providing radiant energy from a source of radiant energy;
• b) conveying said radiant energy via a first pathway means to means for directing radiant energy through the chamber;
• c) directing the radiant energy into and through said chamber to an exit using partial surfaces of an interior conical reflector;
• d) collecting said radiant energy exiting from said chamber;
• and
• e) conveying said collected radiant energy via second pathway means away from said chamber exit;
• f) generating a modulated first optical signal on said first pathway means;
• g) generating a modulated second optical signal on said first pathway means;
• h) detecting a colorimetric optical signal on said second pathway means;
• i) demodulating said first optical signal;
• j) demodulating said second optical signal;
• and
• k) relating the first and second demodulated optical signals to a colorimetric endpoint;
• wherein said means for directing radiant energy into and through said chamber to said exit and said means for collecting radiant energy comprises partial surfaces of at least one interior conical reflecting surface.