A Novel Data Acquisition Method for Visualization of Large pH Changes by Chemical Imaging Sensor

A chemical imaging sensor is a semiconductor device that can visualize the pH distribution in a solution. In the conventional constant-bias method, in which a photocurrent map is converted into a pH image, the measurable range of pH values is rather limited and the result is interfered by the impedance of the solution. In this study, a novel method of data acquisition and image construction is proposed, which can measure a larger pH change without interference of the impedance.