Advanced Product Development

Doty High-Performance

MRI Head Gradient Coils

•  Highest Continuous Gradients (70 mT/m @ 520 A)

•  Ultra-fast Slew Rate (380 T/m/s @ 700 V)

•  Exclusive, Force-Canceled, Ultra-Quiet Gradients (30 dB  quieter)

•  Large ROI (175 mm dsv for 4% rms local gradient non-uniformity; 240

   mm for 10% rms)

•  Minimal distance (9 cm) from shoulder to edge of ROI

•  Ultra-fast Recovery (RRG < 0.1% in 80 cm magnet)

•  Reduced Nerve Stimulation

•  High Reliability (R < 0.15 ohm; 1200 V hi-pot test)

•  36 cm ID, 53 cm maximum OD, 110 kg, water cooled

Download Head Gradient Coil R&D Technical Poster

View Presentation at ISMRM 2005 - on our Head Gradient Coil

Parameter	Units	Doty Head Gradient coil
Peak Gradient, GP	mT/m	140
Continuous Gradient, GC, each axis, all three applied simultaneously	mT/m	40
Slew Rate (αV/L) @ VP & IC	T/m/s	650
Acoustic Noise, EPI, 3T	dBA	95
Peak current	A	1000
RMS current, IC, each, 3x	A	290
Peak Drive Voltage, VP	V	1200
Rise time to 35 mT/m	μs	58
Clear I.D.	mm	350
Outside diameter, do	mm	540
4% ROU DSV, d1	mm	200
9% ROU cent. dia., d2	mm	240
Shielding effectiveness	%	99.5%
Peak bore temperature	οC	21
Min. gradient coefficient, α	mT/A-m	0.14
Max. L	μH	260
Max. RE	Ω	0.17
# resistive shims		4
Special features		ultra short
Grad. null point, ±zo	mm	158
Min. coil half-length, ho	mm	195
Total mass	kg	110