Not always how a microscope works though. This article has a nice little comparison of a few different methods, not all of which measure (only) reflection http

Not always how a microscope works though. This article has a nice little comparison of a few different methods, not all of which measure (only) reflection https://en.wikipedia.org/wiki/Dark-field_microscopy https://en.wikipedia.org/wiki/Dark-field_microscopy There’s also a whole world of microscopy where emissions from the sample itself are measured, often because parts of it have been tagged with fluorescent probes.