All pixel spacing related attributes are encoded as the physical distance between the centers of each two-dimensional pixel, specified by two numeric values.
The first value is the row spacing in mm, that is the spacing between the centers of adjacent rows, or vertical spacing.
The second value is the column spacing in mm, that is the spacing between the centers of adjacent columns, or horizontal spacing.
To illustrate, consider the following example:
Pixel Spacing = Row Spacing \ Column Spacing = 0.30\0.25.
All pixel spacing related attributes shall have positive non-zero values, except when there is only a single row or column or pixel of data present, in which case the corresponding value may be zero.
Note: A single row or column or “pixel” may occur in MR Spectroscopy instances.
This description applies to:
Pixel Spacing (0028,0030)
Imager Pixel Spacing (0018,1164)
Nominal Scanned Pixel Spacing (0018,2010)
Image Plane Pixel Spacing (3002,0011)
Compensator Pixel Spacing (300A,00E9)
Detector Element Spacing (0018,7022)
Presentation Pixel Spacing (0070,0101)
Printer Pixel Spacing (2010,0376)
Object Pixel Spacing in Center of Beam (0018,9404)