Parallel Interdigital Capacitor : Physics involved in the problem.

Hello world,
I have a particular problem, I need to resolve the Parallel Interdigital Capacitor Equation's, specifically I have two plates with five fingers each one, one plate is fix and the other one is movil, so How I can calculate the overlapping capacitance? (Note: Is important to consider the edge effects because the geometric characteristics are very small - micrometer order) How I can calculate the displacement capacitance?

The scheme is Similar to the patent http://www.google.com.lb/patents/US20100039193

My general idea is

CTotalOverlaping= Cideal* + Cedges** +CAdjacentFingers
CTotalDiplacement=Cedges

*Cideal=Permitivity*AreaFinger/Distance between plates --> (Ideal Capacitance - Uniform Electric Field)
**Cedges=Cfringe???


What about the fringe capacitance? What about the adjacent fingers?

But I don't know how follow, I'm really lost

Any Ideal?????

Regards,

Siceron