A therapeutic hand device comprising a wrist-support section and a separate fingers-support section. The first conductive layer is bonded to the second dielectric layer, and the second dielectric layer is bonded to the third conductive layer. A sealant is interposed between the first substrate and a second substrate for sealing the liquid crystal layer. Transmitters 11,21 modulate the plane of polarization of laser light, and emit the result as a transmission signal. The size of the apparatus, and location of an optional neck and cap section, allows for its manipulation by standard automated assay equipment, further making the apparatus ideal for high throughput applications.