This article covers the following topics:

• Introduction
• Spatial Linearity of Pixel Size Verification
• CTP404 Module Target Spacing

Introduction

Spatial Linearity information is given for the following Catphan® models: 500, 503, 504, 600, and 700.

The spatial linearity is the reported estimated pixel spacing. The distance between the spatial targets is measured (the small Teflon and air plugs) and from the known distance the real pixel spacing is calculated.

Spatial Linearity of Pixel Size Verification

The spatial linearity is the reported estimated pixel spacing. The distance between the spatial targets is measured (the small Teflon and air plugs) and from the known distance the real pixel spacing is calculated.

These 3mm diameter holes are positioned 50mm on center apart. By measuring from center to center the spatial linearity of the CT scanner can be verified. Another use is to count the number of pixels between the hole centers, and by knowing the distance (50mm) and number of pixels, the pixel size can be verified.

CTP404 Module Target Spacing

Please note: The Teflon pin is used for identification and orientation only. The ability to change the Teflon pin position enables organizations with more than one Catphan® phantom to identify their phantoms by images of the first section.