Angled Mirrors & Multiple Reflections
Mirrors reflecting other mirrors
A mirror reflects everything in front of it including another mirror. If you place two mirrors at an angle, you increase the number of reflected images you can see. Depending on the angle you choose, you can see a number of unbroken reflections and one or more composite or partial reflections. When the mirrors are set at 90º and 60° degrees exactly, the composite reflection is evenly divided so it looks like a single image.
The angles of incidence and reflection
Without going into exquisite detail, what you see also depends on where you stand and where you place the object – the angles of incidence and reflection. In these examples, we have placed the object and taken the photographs from the center of the angle.
You can try these effects yourself with two small mirrors and our chart.
Two mirrors in a straight line reflect an object only once.
Two mirrors set at any angle between 180º and 90º reflect an object 2 times. As the angle approaches 90º, you see one mirror reflected in the other, but you do not see additional reflected objects.
Two mirrors at a right angle (90º) show two complete reflections and one composite reflection. An angle less than 90º shows two straight reflections and two partial reflections.
At 72º you see 4 complete reflections.
At 60º you see five reflections – four straight and one composite.
At 45º you see the object reflected 3 times in each mirror and one composite reflection for an apparent total of 7 reflections – or 8 if you count the object itself.
Unless the mirrors are very large, it is hard to see into an opening of less than 45º.
When two mirrors are parallel to each other, the number of reflections is infinite. Placing one mirror at a slight angle causes the reflections to curve.
Increasing the number of flat mirrored surfaces or facets increases the number of reflections, but what you see depends on where you stand. The number of complete and partial reflections changes as you view the mirror from different angles.