Monitoring of photo-aging of light-based chemical indicators using illumination-brightness differential scheme

摘要

Photo-aging monitoring of light-based chemical indicators that experience performance degradation as the cumulative amount of light exposure from measurement and/or reference illumination increases from usage. Differing regions on a chemical indicator are illuminated with measurement illumination light of differing exposures, for example, higher brightness, longer exposure times, or both. Readings from the differing regions are compared with known aging information for the chemical indicator at issue to determine a confidence factor for the measurements. The confidence factor can be used to control various actions relating to measurements acquired from the chemical indicators, such as compensating measurement readings for photo-aging, assigning confidence levels to measurement readings, and issuing alerts to users when photo-aging exceeds one or more predetermined thresholds.

主权项

1. A method of monitoring photo-aging of a chemical indicator in an aquatic-environment monitoring/measuring system, comprising:
taking, over a first period of time and using an optical reading system, a plurality of first optical readings from a first illumination spot on the chemical indicator, wherein each of the first optical readings is based on illuminating the first illumination spot with measurement light that creates a first exposure value; taking, over a second period of time and using the optical reading system, a plurality of second optical readings from a second illumination spot on the chemical indicator, wherein each of the second optical readings is based on illuminating the second illumination spot with measurement light that creates a second exposure value that is different from the first value so as to create an exposure differential; generating exposure-differential data as a function of the exposure differential; and using the exposure-differential data to determine whether or not to take a remedial action relative to measurements acquired from the chemical indicator by the aquatic-environment monitoring/measuring system.