Single-exposure modulation-based structured illumination microscopy using spatial area phase-shift

•In structured illumination microscopy (SIM) is an established method for 3D measurement. In SIM, the vertical scanning position with the maximum modulation is implemented to reshape the surface topography. In this paper, we explore a novel MSP-SIM technique to decode the modulation distribution from single exposure. In the proposed method, n pixels from one period of illuminated pattern are used to replace the corresponding n images in the temporal phase shift. Through combining the phase information of each pixel with the least square algorithm, the modulation distribution is achieved. There are several advantages can be concluded from proposed technique.•In traditional temporal phase shift SIM technique (TP-SIM), multiple images with a fixed phase-shift are required, which results in low efficiency and complex phase-shifting mechanism. In proposed MSP-SIM, the modulation distribution is decoded from single frame that greatly enhances the measurement efficiency.•Compared with frequency analysis method such as Fourier transform algorithm, the proposed method can effectively reduce high frequency information loss.•The simulations and experiments performed on smooth curved surface and step sample demonstrate the feasibility of MSP-SIM.