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Dear team- maybe someone can help me in solving the problem

I.e. I have simple problem just it is made of optics and mechanics, i.e.

I have some thin film membrane and I want to find the pressure difference
of membrane using laser light and reflection or diffraction the working principle is more thoroughly in working principle

Please be kind and let me know if you have some idea.



4. Working principle

Most described and used pressure sensor is micro-electromechanical pressure sensor, working principle of which is based on deformation of polysilicon micro-membrane and change of resistance connected in Wheatstone configuration. Novel modeled MOEMS pressure sensor is made with periodical diffraction grading, which is integrated with semiconductor laser diode and photo element matrix. The grading in the micro-membrane is performed using some specific etching techniques. Working principle of particular pressure sensor can be described as follows: beam of the laser in diffraction grating is splitted into exactly described positions (diffraction maximums). If some pressure is applied deformation of micro-membrane changes distance between diffraction maximums. And this displacement change can be calibrated in pressure units, like change in resistance is calibrated into pressure units in the case of piezoresistive sensor. Changing distance between elements making optical pair, sensitivity of the device can be increased remarkably. Principle scheme of the object without optical grating and with it is presented in Fig 4.1, 4.2 respectively.


P.S. I also attach the scheme of the object under investigation -please check

if you have some ideas please write info@kitesurfing.lt

I really appreciate that