Conventional hyperspectral imaging systems simultaneously capture two of the three dimensions
(x, y, λ) of a hyperspectral cube, but require the third dimension to be captured over time. Line-scan systems, where the second spatial dimension is collected through platform movement or scanning, require stabilized mounts or accurate pointing information to ‘reconstruct’ the image.
In wavelength scanning systems, spectral smearing can occur if there is movement within the scene, invalidating spectral correlation/detection. In addition, much of the spectral information collected by such systems, as with spatially invariant systems, contains more detail than is required for detection and tracking.
Surface Optic Corporation’s (SOC) Full Motion Video – Spectral Imaging (FMV-SI) system simultaneously captures and processes all three dimensions of a spectral cube at 60Hz video rates through a novel, plenoptic based design using a single focal plane array.
When coupled to SOC’s MIDIS embedded processor (figure 2); calibration, correction and band selection can be carried out in real-time significantly reducing data volume. The processor also contains 64 real-time correlation processors for detection and discrimination without the need for a PC or GPU and can output standard NTSC signals for real time monitoring.
Table 1 provides system specifications for the SOC716-VNIR system. Systems are also available in the UV (300-500nm), and SWIR (1000-1700nm) spectral ranges, see additional specs for these models.
| Table 1. VNIR Specs | |||
|---|---|---|---|
| Spectra Dispersion | Bandpass filter array | Spectral Range | 450-950 nm |
| Bands / Resolution | 16 / Configurable | Objective Lens | Custom telecentric achromatic |
| Focal Length / TFOV | 85mm / 12.3 Degrees | Image Sensor Type | Si-CCD |
| Cube Dimensions | 640 x 540 x 16 (C x R x λ) | Bit Depth | 12-Bit |
| Cube Scan Rate | 60 cubes per second, max | Size | 6.78″ x 4.5″ x 5.6″ |
| Weight | 7.83 lbs | Power | 12 Watts @ 12VDC battery |
The following video shows the instrument performing spectral tracking on a friendly vehicle of interest.