|TEROS 31 Tensiometer manual||Manual||PDF, 1.8MB||Download TEROS 31 Tensiometer manual Manual|
|TEROS 31 Quick Start||Quickstart Guide||PDF, 1.4MB||Download TEROS 31 Quick Start Quickstart Guide|
|TEROS 31 Integrator Guide||Integrator Guide||PDF, 0.6MB||Download TEROS 31 Integrator Guide Integrator Guide|
Millimeter scale is tough. Centimeter scale, I would say yes. Check out the TEROS 31 Tensiometer. The diameter of the shaft is 5 mm, and the water potential measurement with the TEROS 31 is extremely precise. You should be able to quantify a water potential gradient across about 1-2 cm with a pair of these. But to answer your question, I don’t know of any instrument small enough for mm scale measurement. There was a group working on a MEMs tensiometer that could maybe do that, but I don’t think it is on the market presently.