The lie detector test is also known as polygraph test.
Let's discuss about the devices in it that are used to caught a person :
The first device is Galvanograph which is connected to tips of person. A change will occur in activities of person if he lies and fingertips will release sweat because of the stress, and that will come in contact with plates of Galvanograph. The electric current will generated which will flow to polygraph device that will generate the visuals of these signals.
The device connected to chest of person is called Pneumograph, which remains filled with air and pipe is used in it. The respiration rate will increase or decrease if he lies, because of which air pressure inside pipe will change and will be displayed in form of signals by this polygraph record.
The next device is Cardiosphymograph which is connected to left upper arm and is attached to polygraph by a tube. When pressure travels through the vessel with some pressure, it creates some minute vibrations, and the polygraph record those vibrations and ultimately show them in visual form.
Let's discuss about the devices in it that are used to caught a person :
The first device is Galvanograph which is connected to tips of person. A change will occur in activities of person if he lies and fingertips will release sweat because of the stress, and that will come in contact with plates of Galvanograph. The electric current will generated which will flow to polygraph device that will generate the visuals of these signals.
The device connected to chest of person is called Pneumograph, which remains filled with air and pipe is used in it. The respiration rate will increase or decrease if he lies, because of which air pressure inside pipe will change and will be displayed in form of signals by this polygraph record.
The next device is Cardiosphymograph which is connected to left upper arm and is attached to polygraph by a tube. When pressure travels through the vessel with some pressure, it creates some minute vibrations, and the polygraph record those vibrations and ultimately show them in visual form.