FTA4000 Drop and Sample Sizes
The FTA4000 is optimized for high magnification and small sample sizes. There are several factors which determine how large the sample can be.
For interfacial tension work
The pump can deliver any volume in the microliter range, in addition to its small volume capabilities. It has a nominal capacity of 4 microliters but can be draw additional liquid from its source vial by controlling its inlet and outlet valves (multi-stroke capability).
The field of view of the microscope must be large enough to include the full pendant drop. This can easily be 3 or 4mm. To provide the full range of view sizes one might want, adaptors are available to scale the magnification down in multiples of 2.
For contact angle work
Stage size is the main limitation. The stage is necessarily small because the working distance of the microscope is 35mm. The stage is circular and rotates to bring various samples into view. The recommended maximum sample size is 15mm x 15mm x 5mm thick, although samples can be longer along one axis without causing great difficulty.