Proximity sensorA proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. A proximity sensor often emits an electromagnetic field or a beam of electromagnetic radiation (infrared, for instance), and looks for changes in the field or return signal. The object being sensed is often referred to as the proximity sensor's target. Different proximity sensor targets demand different sensors. For example, a capacitive proximity sensor or photoelectric sensor might be suitable for a plastic target; an inductive proximity sensor always requires a metal target.
Marcel DuchampHenri-Robert-Marcel Duchamp (UKˈdjuːʃɒ̃, USdjuːˈʃɒ̃,_djuːˈʃɑːmp, maʁsɛl dyʃɑ̃; 28 July 1887 – 2 October 1968) was a French painter, sculptor, chess player, and writer whose work is associated with Cubism, Dada, and conceptual art. He is commonly regarded, along with Pablo Picasso and Henri Matisse, as one of the three artists who helped to define the revolutionary developments in the plastic arts in the opening decades of the 20th century, responsible for significant developments in painting and sculpture.
