Optically transparent, relatively high refractive index polymeric compositions and ophthalmic devices such as intraocular lenses, contact lenses and corneal inlays made therefrom are described herein. The method may vary the luminance of a light source illuminating a plurality of displayed pixels and vary the transmittance of a light valve of the display. The foam reservoir is retained in place by means of a clip which abuts the top of the foam reservoir. Installation and disassembly may thus be done faster to save assembly and repair costs. The probe system preferably employs an uncomplicated mount using a single pipe fitting and clamp.