Tag: optical path difference

Phase-contrast microscopy is a specialized optical imaging technique that transforms invisible phase shifts in light passing through a transparent specimen into brightness changes in the image. This method is essential in medical and biological research because it allows for the detailed visualization of live, unstained cells and microorganisms that would otherwise appear invisible under a standard brightfield microscope. By exploiting the differences in the refractive index between cellular structures and their surrounding medium, clinicians and researchers can observe physiological processes in real-time without killing or distorting the sample.