The mirror with the little lever on the bottom is caller a prismatic rear view mirror. Most just use the common name of night vision mirror.
The glass of the mirror is cut at a angle and the backing on the glass is straight. In day vision you are using the highly reflective glass backing. When you flip it you are only seeing the reflection off the glass front.
Auto adjust mirrors that do this automatically use electro chromatic glass that basically tints allowing less light to reach the driver.