6.1	WFC3 UVIS Imaging

As described in Chapter 2, the optical design of WFC3 features two independent channels, each with its own separate optics, filters and grisms, and detectors. The UVIS channel is sensitive to UV and optical wavelengths (200-1000 nm), and the IR channel is sensitive to near-infrared wavelengths (800-1700 nm).

Only a single channel, either UVIS or IR, can be used at any one time. Thus they cannot be used in parallel, but they can be used sequentially within the same orbit.

A schematic diagram showing the locations of the fields of view of the UVIS and IR detectors in the HST focal plane is shown in Figure 2.2.

This chapter describes the capabilities of the UVIS channel. The following chapter, Chapter 7, describes the IR channel. Detailed performance characteristics of the detectors used in both channels are given in Chapter 5 and summarized in Table 5.1.