A nanosecond time-resolved imaging technique has been developed for the observation of the photo-excited charge carrier dynamics in photo-devices such as photocatalysts and solar cells. An arbitrary spatial pattern of pump pulse light excites the charge carriers, which are observed by phase-contrast imaging. This patterned excitation is preferable for various statistical image reconstruction techniques based on robust principal component analysis and the least absolute shrinkage and selection operator, which helped the enhancement of the signal-to-noise ratio and the removal of unwanted image components. By using data assimilation with the charge decay model, the lifetime and diffusion coefficients were mapped for the photo-excited electrons in a nano-particulate titanium oxide film and other photo-device materials.