Application Note

Fluke IR Window eld of view
75 mm (3 in)
window
73.66 cm (29 in)
22.1 cm
(8.7 in)
3 inch IR Window FOV with Standard Lens
30.48 cm
(12 in)
50 mm (2 in)
window
38.1 cm (15 in)
19.76 cm
(7.78 in)
3 inch IR Window FOV with Standard Lens
30.48 cm
(12 in)
100 mm (4 in)
window
96.52 cm (38 in)
24.2 cm
(9.53 in)
4 inch IR Window FOV with Standard Lens
30.48 cm
(12 in)
These Field of View (FOV) calculations are based on best practices used during infrared inspections and serve as a guide when
choosing IR Window sizes and locations.
Please note that the illustrations represent achievable FOV at a distance of 30.48 cm (12 in) to target. Additional FOV
calculations at various distances to target are given in the tables below. Actual FOV can vary based upon equipment layout
(phase barriers, internal compartments, etc.). Be sure to verify IR Window position before drilling holes for installation.
For illustration purposes, only horizontal FOV is shown. Adjusting the position of the thermal imager allows the overall
FOV to be achieved in all directions—360 degrees.
All calculations based on Fluke Ti32 Thermal Imager with standard lens (23° x 17°).
IR window
size
Distance to target
15.24 cm
(6 in)
30.48 cm
(12 in)
45.72 cm
(18 in)
60.96 cm
(24 in)
100 mm (4 inch)
53.34 cm
(21 in)
96.52 cm
(38 in)
139.7 cm
(55 in)
182.88 cm
(72 in)
75 mm (3 inch)
40.64 cm
(16 in)
73.66 cm
(29 in)
109.22 cm
(43 in)
142.24 cm
(56 in)
50 mm (2 inch)
20.32 cm
(8 in)
38.1 cm
(15 in)
53.34 cm
(21 in)
68.58 cm
(27 in)