Patent ID: 7278318
Filing Date: 2007-10-09
Classification: G01L

Abstract:
1. A relative pressure sensor, or pressure-difference sensor, comprising: a measuring apparatus having: a first half-chamber defining a first volume; a first separating membrane for sealing said first half-chamber, and having a first membrane stiffness; a second half-chamber defining a second volume; a second separating membrane for sealing said second-half chamber, and having a second membrane stiffness; and a measuring membrane which separates said first half-chamber from said second half-chamber, wherein: said first-half chamber is filled with a transfer liquid having a first coefficient of thermal expansion, and said second half-chamber is filled with a second transfer liquid having a second coefficient of thermal expansion; a first product of said first membrane stiffness, said first volume and said first coefficient of thermal expansion is essentially equal to a second product of said second membrane stiffness, said second volume and said second coefficient of thermal expansion; and at least one factor of said first product deviates from the corresponding factor of said second product.