Application Note

Modification of this document is not permitted without written permission from Fluke Corporation.

A maximum attainable FOV (roughly 6xD) can be achieved by positioning

a thermal imager at extreme angles. These angles require that the view

through the thermal imager include seeing both through the IR Window

(inside the enclosure) and beyond the IR Window (outside the enclosure).

Such positioning does not expose the entire surface of the camera lens to

the target being measured and when combined with the steep viewing

angle, slightly less accurate results should be expected.

Wide-angle lenses

Compared to a standard lens (23° x 17°) a wide-angle lens (46° x 34°)

offers a larger FOV when positioned perpendicular to the IR Window, as

shown. However, the size of the wide-angle lens itself limits the ability

to position the thermal imager at much of an angle. This means that the

achievable FOV with a wide-angle lens, obtained by angling the ther-

mal imager, is actually less than that of the standard lens. This can vary

based on camera model.

Calculations based on Fluke Ti32 with wide-angle lens (46° x 34°)

75 mm (3 in)

window

63.75 cm (25.1 in)

40.89 cm

(16.1 in)

3 inch IR Window FOV with wide angle Lens

30.48 cm

(12 in)

75 mm (3 in) wide-angle lenses

Distance to target 30.48 cm (12 in)

FOV 63.75 cm (25.1 in)

For more information on Fluke IR Windows,

call 1-800-760-4523 or visit www.ﬂuke.com/irwindows

Extreme angles