The Raspberry Pi camera comes with ribbon cable which is connected to the Camera Serial Interface (CSI) found on the Pi 3 board. The camera is a tiny board itself with dimensions 25mm x 23mm x 9mm and weighing around 3 grams, making it easier and useful for application where the size and weight are very important. But this module is only capable of taking images and videos but not sound. This camera module can be used for taking pictures, recording videos, motion detection and for surveillance and security applications.
The code to access the camera and take images/videos is done through python programming language. Since we are only going detect the person in front of the mirror, a 5MP resolution camera is enough. The sensor found in the 5MP camera module is OmniVision OV5647.
The monitor is used to display the personalized information and contents on it’s screen. This will be mounted behind the two-way mirror. An array of devices can be used as display, the prominent ones being a LCD or a LED television, a touch screen monitor or a regular monitor. This display selection is based on personal preference.
Since we are only building a prototype, we have opted for a 20″ HCL.A two-way mirror is placed in front of the monitor. This serves as a mirror and also displays the contents on the monitor on the surface of the mirror. Since in a regular mirror, after the back pane of the glass is given a coating of reflective material in a process called silvering, it is painted black. This is done in order to ensure that all the light is reflected forward, making it impossible for the light to pass through it.In a two-way mirror, the glass is partially reflective and partially transparent i.e.
semi-transparent. Here the glass is coated with a thin layer of metal (usually aluminium). This layer is very thin and almost transparent thereby allowing only half the light to reflect back while the rest passes or penetrates through it. When the display is switched off, this acts like a regular traditional mirror and the user is able to see their face. When the display is on, the content on the monitor as well as the user’s face can be seen on the mirror surface since this is semi-transparent. In simpler terms, when the display behind it is black or darkened, it must behave like a regular mirror, and when information is displayed on the monitor, it should be like a glass window.
