Time-of-flight widefield microscopy

High-resolution depth imaging is essential in fields such as biological microscopy and material science. Traditional techniques like interferometry and holography often rely on phase stability and coherence, making them susceptible to noise and limiting their effectiveness in low-light conditions. We propose a time-of-flight (ToF) widefield microscopy technique that uses pseudo-thermal light. Our method calculates second-order correlation <i>g</i> ⁽²⁾ from intensity images captured by a standard CMOS camera, eliminating the need for phase stability and improving robustness in noisy environments. By incorporating a dual-wavelength approach, we further enhance depth-uncertainty to nanometer scales. We demonstrate the effectiveness of this technique through experiments on biological samples and nano-scale graphene layers, highlighting its potential for high-precision depth-resolved imaging.