How to use a two way mirror
With careful consideration when installing a two way mirror, a dramatic difference can be made to its overall effectiveness. We recommend that you think beforehand how it’s going to blend with the surrounding environment with special care taken about the positioning to get the best use of the available ambient lighting conditions.
IMPORTANT: In order to maximise the functionality of the product, it's important that there is a significant light difference between the two sides.
FOR OBSERVATION. IT HAS TO BLEND.
Try to put an everyday abject partially in front of the mirror. e.g. plant or vase. This will take the casual eye away from the mirror as a whole.
IN ALL CIRCUMSTANCES IT HAS TO BE PROPERLY LIT.
The viewing area must be darker than the area to be observed for the special mirror surface to work properly. The large the light difference the better the result.
IT HAS TO BE SECURELY HUNG ON A WELL PREPARED WALL.
For framed mirrors, this avoids detection by simply lifting the mirror up to reveal the observation area. Or allowing light to leak behind and spoil the effect.
IT HAS TO BE PROPERLY MAINTAINED.
Scratches in the surface can lead to light penetration through the 2 way surface and ruin the overall effect. With TV installation for instance, always make sure the coated surface is on the inside and away from any possible accidents.
Spy-Mirror, One-Way Mirror, Three Way Mirror
Semi Silvered Glass, Half Silvered Mirror
VisiGlass, Observation Glass, Security Glass
A two-way mirror is often called a "one-way mirror" by members of the general public. The misconception is that such a mirror acts as a mirror from one side, and acts as a window (letting light through) from the other side. Actually, the two-way mirror is letting about half of the light through, and reflecting the other half of the light, from both sides. it is also called a half-silvered surface, as just enough reflecting metal film is deposited on the glass, so that about half of the light is reflected.
So, why does a two-way mirror seem to behave like the two sides are different? It behaves this way when one side is in the dark. Then almost no light goes from the dark side to the light side, and almost no light is reflected back from the dark side to the dark side. Most of the light comes from the bright side. Plenty of light travels through the mirror, and plenty of light is reflected back. To people on both sides of the mirror, the light from the bright side overwhelms the light from the dark side. So, people on the bright side see a mirror, and people on the dark side see a window. See the diagram.