03.06.2015 Views

Understanding Infrared Thermography Reading 3

Understanding Infrared Thermography Reading 3

Understanding Infrared Thermography Reading 3

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Total Field of View (FOV total )<br />

For scanners and imagers. total field of view denotes the image size in terms<br />

of total scanning angles for any given lens. An example of a typical total field<br />

of view specifi cation would be "TFOV = 20 degrees vertical x 30 degrees<br />

horizontal" (with standard Ix lens) and would define the thermogram total<br />

target size by a simple trigonometric relationship:<br />

tan θ/2 = V/2∙d -1<br />

V = 2 ∙ tan (y/2) ∙ d, for θ = y<br />

d = working distance,<br />

H = total horizontal image size,<br />

V = total vertical image size,<br />

x = horizontal scanning angle,<br />

y = vertical scanning angle.<br />

θ = y or x<br />

This is illustrated in Figure 3. 10.<br />

Charlie Chong/ Fion Zhang

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!