Abstract
In a LCD panel that has equipped with pixel photo sensors for image capture, the ambient light intensity detection is critical for the read-out circuit. In this study, for simulation purpose, we use CMOS optical sensors as detecting element and their spatial filtering signal as an indicating factor for improving the read-out circuit efficiency. In the further study, TFT array will be used for similar investigation. This thesis aims at developing an efficient method for backlight light intensity detection in touch panel. By catching a fixed backlight light source frequency we can detect the touch on the panel even working in the dark. This new touch approach will change the way we use and control the mobile phones and panel. The detecting circuits for the touch panel are integrated directly onto the screen and this makes products lighter and smaller with added portability and convenience.