a temperature correcting pressure gauge which has a substrate having at least one surface coupled to a source of pressure to be measured , the substrate first surface having a first fiber bragg grating from a first optical fiber attached in an appropriately sensitive region of the substrate , a fiber bragg grating from a second optical fiber attached to the opposite surface from the first fiber bragg grating , the first and second fiber bragg gratings reflecting or transmitting optical energy of decreasing or increasing wavelength , respectively , in response to an applied pressure . the first and second fiber bragg gratings have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the fiber bragg gratings also have closely matched pressure coefficients and temperature coefficients .