Lloyd's Mirror


A front surface mirror is brought close to an expanded laser beam at a very small grazing angle. Interference lines are formed on a screen.


Adjustment: 1) get the mirror far from the laser, and insert a wedge under the mirror, you will see two separated dots on the screen. 2) sliding out the wedge gradually while bring the mirror towards the laser in order to bring two dots together and get overlapped.
Lens: PASCO converging lens, 10cm
Lens to mirror distance: ~27cm
Mirror to screen distance: ~255cm (screen covered by white paper)

Location 18C, 36E