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This question is difficult for me to phrase, so I will do my best, and then attempt to make a "diagram" What would you see, if you looked through a two way mirror, and on the other side, somebody held up a normal mirror? It would be a reflection of a mirror. I have gotten an answer that you would see nothing. This seems logical, but nothing is invisible. DIAGRAM O ---> |---> | \|/ |--->| | | <---| /\ | PERSON 1 NORMAL MIRROR 2 WAY MIRROR


Actually, it depends on what is on the other side, other than the mirrors. If no light is on beyond the 2-way mirror side, you would see darkness. If there is light turned on, you would see a little bit of glare, but not much else. If the mirrors were perfect and the lights were off to the sides, you would see darkness. For your eyes to register light, light must enter your eyes. For light to enter the room you sit it (provided you have no lamps behind you), light must enter from beyond the 2-way mirror. To do this, light must reflect from the far mirror. To do this, light must reflect from the 2-way mirror. This continues on. If there is no source of light that can reach your eyes, your eyes do not respond: darkness. It would be very much like looking through a window between two rooms, neither of which has a light.

Because mirrors are not perfect, a little light from the side can produce a slight image on the far mirror. This would be like what a small lamp to the side can produce on the inside of your window as you look out into the darkness at night (with no streetlights and no moon).

If the mirrors have a maximum size to them, you could get a slightly more dramatic effect. Imagine a line of mirrors, each the size of the mirrors. You look through the whole line of the mirrors, perhaps thousands. Between each window is a copy of the room in which the mirrors exist. Beyond the row of thousands of mirrors is pure darkness.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College

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