What is the method of measuring depth in relation to pressure change in standard dive gauges?

The method of measuring depth in relation to pressure change in standard dive gauges is based on mechanical movement. This principle is primarily utilized through a Bourdon tube mechanism or a diaphragm that responds to changes in pressure. As a diver descends, the pressure of the water increases, causing the tube or diaphragm to deform. The amount of deformation corresponds to the water pressure, which is then translated into a readable depth measurement.

Mechanical movement is favored in standard dive gauges because it provides reliable, direct readings without being affected by electrical issues or sensor calibration problems. This method has been tried and tested over many years in various underwater conditions, making it a robust choice for divers.

Other methods listed, such as optical measurement and electrical sensors, are often used in more advanced or specific types of dive computers and instruments but are not the standard for traditional mechanical depth gauges. Cable connection is not a measurement method for depth but may refer to the way certain devices transmit data rather than measure it directly.