Pressure sensor

Pressure sensor includes a casing having a pressure detection chamber, a diaphragm for receiving pressure of a measuring object and disposed on the casing, and a pressure detection element. The pressure detection chamber is filled with a liquid, and the diaphragm contacts the liquid. The pressure detection element is disposed in the pressure detection chamber to receive the pressure of the liquid. The diaphragm has a plate shape with a radius of R and includes a circumference and a center of the plate. The circumference is fixed to the casing. The diaphragm further includes a corrugate disposed concentrically with the center of the diaphragm and having a half circular cross-section and a top of the half circle. The top of the corrugate is disposed within a distance of 0.6 R from the center of the diaphragm.