Flow2 is our production-grade TD-fNIRS system. Flow2 is designed to give whole-head coverage for most wearers, with 40 module locations. The DevKit uses the same modules and base technology but provides the ability to tailor the hardware setup precisely to your experimental needs by employing a soft cap design. See the below specifications table for comparison of various features.
NOTE:
The DevKit shipment arrives with the 12 modules and 6 EEG electrodes pre-assembled in a soft cap as a reference design. The modules and electrodes can easily be removed for setup in a cap of your own design.
| DevKit System | Flow2 System |
fNIRS Type | Time Domain |
Optode Style | Modular |
Max number of modules | 12 | 40 |
Number of Sources | 36 | 120 |
Number of Time-Resolved Detectors | 72 | 240 |
Number of Channels (Source-Detector Pairs) | 216 | >3500 |
Channel Length (Source-Detector Separation) | 8.5mm to 27mm | 10mm to 60mm |
Source Types | Dual wavelength (690nm/905nm) Laser diodes |
Laser Classification | 
Class 1 (FLPPS 21CFR1040.10) |
Detector Type | Custom Silicon Detector |
Dynamic Range | > 100dB |
Sampling Rate | 3.7hz
|
Number of Dry Active EEG Electrodes | 6 + Reference & Bias | 4 + Reference & Bias |
EEG Sampling Rate | 1 kHz |
Headgear | Custom - Defined by customer. System ships with a soft cap | Fits heads of 52cm - 62cm Circumference and 32cm - 37cm Bitragion Coronal Arc |
Power Supply | USB-PD (Delivered over USB-C) |
Power Consumption | 15W Max | 50W Max |
Data Transfer | USB 2.0 |
Data Storage | Data streamed to acquisition PC at rate of 300MB/min of recording | Data streamed to acquisition PC at rate of ~60 GB/hour of recording |
Output File Formats | SNIRF |
Output Metrics | Oxy/Deoxy/Total Hb per Channel Total counts, 1st and 2nd Moments per Channel Absolute Bulk Tissue Oxygenation per Channel (long within module channels only) |
Power Cable | Up to 10’ USB-C (provided) |
Weight | 1.2kg (Reference design) 1.5kg (Reference design + control box) | 2.5 kg |