What is a Peephole?
Peepholes are useful monitoring devices that make it possible to survey space that is outside of the area currently occupied by the observer. The most common use of the peephole is in the front door of a home or apartment. However, the device is sometimes employed in other applications in the home as well as in the workplace. The actual construction of a peephole viewer is simple. The device is configured with a small cylindrical body. At each end of the cylinder, a set of lenses help to make it possible to peer through the body and observe activity occurring on the opposite side of the cylinder. When installed in an exterior door, the peephole makes it possible to visually determine who has just rung the bell or knocked on the door before actually opening the door. From this perspective, a peephole can be viewed as a security aid. Peephole installation is not hard to accomplish. Essentially, a small hole is drilled through the body of the door at a height that is convenient for the ho
