| 摘要 |
A pH sensor system (10) and method capable of monitoring the pH level of a medium based on the characteristics of a chromatic pH sensitive material employed in the pH sensor system is provided. The pH sensor system includes at least a housing (12) having at least one transparent surface (14); a light sensitive circuitry (15), e.g., a LED (16) and photo-detector (18), enclosed within the housing; and, a chromatic pH sensitive material (20) overlaying at least a portion of the transparent surface having the characteristic of becoming saturated when an ambient pH level reaches a predetermined level such that the light sensitive circuitry detects a different intensity of incident light when the chromatic pH sensitive material is saturated than when the chromatic pH sensitive material is not saturated. As the pH level of the medium, e.g., concrete, storage tanks containing chemical reagents, etc., to be monitored steadily decreases, the pH sensitive material on the transparent surface of the housing will gradually become saturated with hydrogen ions and colorless. When the pH level reaches the predetermined level, the pH sensitive material will be unable to absorb any light being emitted from the LED such that the light is reflected back to the photo-detector.
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