The second generation QZFM sensor (Gen-2) is finally ready for release. In this upgrade, we focussed on mainly two things: (i) reducing the size and weight of the sensor, and (ii) improving manufacturability to support faster production speeds. Along the way, we squeezed out a little more sensitivity and extended the sensor tolerance to background magnetic fields from 50 nT to 200 nT. All other technical specifications of Gen-2 are similar or slightly improved over Gen-1.
For now, the Gen-2 sensor is backward compatible with Gen-1 electronics. We are currently working on a more compact version of the electronics controller (to be released in 2019) which will greatly simplify setup and installation for future high channel count systems.
QZFM Gen-2 (second generation sensor)
The driving force behind Gen-2 design was the desire to help move MEG form factor closer to EEG. It was hard to imagine a sleek and comfortable MEG helmet could be designed using Gen-1 QZFM, which is why we worked really hard to develop Gen-2.
Gen-2 sensors in an off-the-shelf EEG cap.
The table below provides a quick comparison between Gen-1 and Gen-2.
| Metric | Gen-1 | Gen-2 |
| Sensitivity | 15 fT/√Hz | 7-10 fT/√Hz |
| Bandwidth | 135 Hz | 135 Hz |
| Max background | 50 nT | 200 nT |
| Standoff | 6.0 mm | 6.5 mm |
| Size (sensor) | 13.0×19.0x110 mm | 12.4×16.6×24.4 mm |
| Weight (sensor) | 20 g | 4 g |
| Cable Weight | 10 g/ft | 1 g/ft |
| Surface Temp. | ∼45 °C | ∼41 °C |
*Note: The metrics listed above are anticiapted and not Gen-2 specifications.