TABLE II.

System Comparisons

	Robinson 1963 [1]	Primelec [21]	System Described by this Report
Eye Coil(s) Used to Measure Specifications	10 turn/coil 12 mm diam Contact lens	Not specified	21 turn 3–4 mm diam
Dimensions Measured	3D	3D	3D
Technology	Phase Detector	Digital Frequency FFT	Digital Frequency Demodulation
Input Referred Noise (Amplifiers Shorted)	< 2 uV*	--	5 uV
Noise	-	< 0.024 deg p-p “Full Bandwidth” (frequency unspecified, coil not facing field)	0.036 deg p-p (facing field, NO inter-sample filtering)
Linearity	2% full scale	Error ±0.3 deg	Error < 0.1 deg (<0.028%)
Recording Range	--	360 deg HZ ±80 deg Vert	360 deg all directions
Step Response Rise Time	0.5 ms with <10% overshoot	--	2 ms 0 overshoot

^*Robinson defined resolution as the induced scleral coil signal/input referred noise