How to monitor pressure in a touch-free way?

i ask an idea that how to monitore pressure in a nontoutch way.The principle of physics.for example,get a distance by laser

As the pressure of a system is defined as the force exerted by the system on unit area of its boundaries, to measure it one measures the force, and force <=> displacement ..
I don't think there is a sensor that doesn't use displacement of any kind ..

http://www.sensotec.com/pressure_sensor_appnotes1.shtml

Regards,
IanP