The present invention relates to a fluid flow measuring device. As the color sleeve is moved by the motor between the light source and the optical fibers, the color of the light provided to the optical fibers changes thereby changing the color displayed in the tree. The passivation layer has first openings, and each first opening exposes a portion of the corresponding pad respectively. Circuits included in the circuit group include thin film transistors having a gate oxide film thickness suitable to a power supply voltage of 1. The electron beam system and the irradiation zone are configured for irradiating outwardly exposed surfaces of a 3-dimensional article passing through the irradiation zone from different directions with the electrons from the electron beam system. , an even more accurate floor area estimation may be generated.