The present application provides a detection apparatus and a control system, wherein the detection apparatus comprises a passive infrared sensor and a Fresnel lens provided on the passive infrared sensor, and wherein the detection apparatus further comprises a rotation unit, the rotation unit being capable of driving the passive infrared sensor and the Fresnel lens to rotate together. The detection apparatus of the present application can be used for controlling lamplight, air conditioner, heating and ventilation in a building or can be used for security, etc.