Jump to Content
Your Recent History
View Cart
SUBSCRIPTIONS & PRICING
GENERAL INFORMATION
chapter 5, Imaging Introduction
Chapter Contents
- 5.1 The Field of View
- 5.2 Scanners
- 5.3 Strip Mappers
- 5.4 Pushbroom Scanners
- 5.5 Whiskbroom Scanners
Excerpt
Since this text discusses imaging spectrometers, it is necessary that some of the basics of imaging be explored. Two types of images may be defined: a two-dimensional, fixed, rectangular frame and a strip map that is two dimensional but with one dimension arbitrarily long.
5.1 The Field of View
The field of view may be considered as a collection of picture elements (pixels) or resolution elements (reselms). This field can be imaged onto an array of detector elements in a focal plane array (FPA), or it may be imaged by a single detector or small array that is scanned over the field.
I will call the field elements pixels, whether they are measured in linear or angular dimensions. The linear pixel is sometimes called a GSD, for ground spatial distance. The individual detector elements will be called elements. The FPA may be viewed as an array of detector elements, and the idea is to obtain a one-to-one, linear mapping of the pixels onto the elements—or the elements onto the pixels. If there are as many detector elements in the array as there are pixels in the field of view, then the system is called a starer. If not, then some scanning is necessary, and it is called a scanner. The field of view is illustrated in Fig. 5.1.
The required electronic bandwidth for such a system is determined by the Shannon sampling theorem, and is
©1997 Society of Photo-Optical Instrumentation Engineers
PURCHASE CHAPTER ($US12)
SPIE Digital Library
This Publication
Google Scholar
PubMed