Spectroscopic ellipsometry is widely adopted in semiconductor processing, such as in the manufacturing of integrated circuits, flat display panels, and solar cells. However, a conventional spectroscopic ellipsometer, as shown in Fig.1a, typically modulates the polarization state via mechanical rotation of the compensator or analyzer. For spectral detection, it either requires wavelength scanning or the use of a multi-channel spectrometer. The resulting system is often bulky, complex, and require multiple measurements.