During exposure, the CCD absorbs light photons, each of which causes the silicon to release an electron. This allows the light intensity at each part of the spectrum to be measured. To capture an entire camera image, each detector must be five inches square. This is seven times larger in area and sixteen times larger in number of pixels than the largest CCDs now in use. The largest devices that can fit on existing silicon wafers are roughly 2000x4000 pixels.
Conventional spectrographs suffer from severe flexure, or shifts in instrument alignment.
This causes the image to drift on the detector and makes calibration and data reduction difficult. This and other advanced software features should result in hours of extra observation time per night. Likely targets are the oldest stars in our Galaxy, faint stars in nearby galaxies, globular star clusters swarming around other galaxies, and distant quasars near the beginning of time.