An automatic calibration mode for a carbon dioxide sensor is based on using a zero gas. The sensor is designed to recognize a distinctive rate of change pattern of carbon dioxide concentrations that would be indicative of a zero calibration routine. This approach can be used for other infrared senso...http://www.google.com/patents/US6588250?utm_source=gb-gplus-sharePatent US6588250 - Automatic calibration mode for carbon dioxide sensor
