Recent advances in oblique plane microscopy

Oblique plane microscopy (OPM) directly captures object information in a plane tilted from the focal plane of the objective lens without the need for slow z-stack acquisition. This unconventional widefield imaging approach is made possible by using a remote focusing principle that eliminates optical aberrations for object points beyond the focal plane. Together with oblique lightsheet illumination, OPM can make conventional lightsheet imaging fully compatible with standard biological specimens prepared on microscope slides. OPM is not only an excellent high-speed volumetric imaging platform by sweeping oblique lightsheet illumination without mechanically moving either the sample or objective lens in sample space, but also provides a solution for direct oblique plane imaging along any orientation of interest on the sample in a single shot. Since its first demonstration in 2008, OPM has continued to evolve into an advanced microscope platform for biological, medical, and materials science applications. In recent years, many technological advances have been made in OPM with the goal of super-resolution, fast volumetric imaging, and a large imaging field of view, etc. This review gives an overview of OPM's working principle and imaging performance and introduces recent technical developments in OPM methods and applications. OPM has strong potential in a variety of research fields, including cellular and developmental biology, clinical diagnostics in histology and ophthalmology, flow cytometry, microfluidic devices, and soft materials.