| thickness | skin depth | sensitivty loss |
| 10 | 30 | 0,283468689 |
| 15 | 30 | 0,39346934 |
| 20 | 30 | 0,486582881 |
| 25 | 30 | 0,565401791 |
| 30 | 30 | 0,632120559 |
| 35 | 30 | 0,688596776 |
| 40 | 30 | 0,736402862 |
| 45 | 30 | 0,77686984 |
| 50 | 30 | 0,811124397 |
| 55 | 30 | 0,840120254 |
| 60 | 30 | 0,864664717 |
| 65 | 30 | 0,885441156 |
| 70 | 30 | 0,903028032 |
| 75 | 30 | 0,917915001 |
| 80 | 30 | 0,930516549 |
| 85 | 30 | 0,941183528 |
| 90 | 30 | 0,950212932 |
Alright so about 3 times the skin depth for 95% sensitivity. At half the skin depth I lose about 60% of sensitivity.
I'm trying to measure vibrations in a very thin stretched membrane (a few tens of microns). Displacement of the membrane will only be a few microns, depending on the thickness, stifness and size of the membrane. So ideally my resolution should be as fine as possible (sub micron).
The membrane will be very close to the coil, probably less than a mm.
I have another question regarding my application can I ask this in the same thread or do you prefer a new thread?
Thanks for the help
