1, a mirrorless camera is also a kind of camera without a reflector, also known as a half-lens camera. In most cases, what we call "micro-single" is a mirrorless camera, but "micro-single" is strictly a Sony patent. The full name of SLR is single-lens reflex camera, which refers to a camera where light shines on the reflector through the only single-lens lens and takes a view through reflection.
2. The electronic viewfinder used by the mirrorless camera, in which light directly enters the camera sensor from the lens; SLR cameras use optical framing.
3. Due to its long history, SLR has more choices on the lens; Although the lens group in a mirrorless camera has been gradually improved after several years of development, similar super telephoto lenses are often bulky, which makes it meaningless for a mirrorless camera to give consideration to portability.