1：Experimental Design and Method Selection:

An imaging setup based on selective infrared (IR) radiation sources and a mid-IR sensitive camera was used to monitor the distribution of water concentration inside the packaging of devices and its change over time. The system utilizes the absorption band of water around 1920 nm and a reference band.

2：Sample Selection and Data Sources:

Glass was used as a barrier material, with water ingress through the adhesive as the only path of water ingress into the device. Samples were exposed to damp heat conditions (85 °C and 85% relative humidity) according to the stability testing protocol ISOS-D-

3：List of Experimental Equipment and Materials:

Equipment included a dispensing robot for encapsulation process, UV light for curing, a profilometer for thickness measurement, a broadband spectrometer for spectral measurements, damp heat chambers for controlled exposure, a high-precision weighing scale for gravimetric measurements, and an IR absorption imaging setup with components like gray body radiators, optical diffusor, multi-reflection mirror tube, NIR objective, optical bandpass filters, and a mid IR camera.

4：Experimental Procedures and Operational Workflow:

The encapsulation process involved distributing epoxy adhesive over a top barrier sheet, adding a bottom barrier sheet, and curing under UV light. Samples were then exposed to damp heat conditions, and IR absorption images were taken before and after exposure to monitor water ingress.

5：Data Analysis Methods:

The optical density image (ODI) of the sample was calculated from the raw images, and changes in optical density due to water uptake were analyzed. FEM simulations were performed to compare with experimental data and determine the diffusion coefficient of water.