Building Earth Observation Cameras

195Pushbroom Imagers

provide further corrections to have a at eld. This optical scheme provides

good image quality over a FOV of 4.3°.

The spectral separation and detection is carried out by a FPA, which con-

sists of a beam splitter assembly and an optical butting unit with associated

CCDs. The optical schematic of the beam splitter is shown in Figure 6.30b.

The assembly essentially consists of a set of prisms with dichroic coatings

at appropriate faces. The green band B1 is reected by dichroic mirror-1.

Thered (B2) and IR (B3) are separated by dichroic mirror-2. The PAN band

is directly transmitted through the prism. Spectral responses for ...