Fluke Ti200, Ti300, Ti400 Service Guide

Thermal imaging

Spot Size = 0.255 cm x 0.255 cm

(Based upon IFOV theoretical*)

0.41 m

0.31 m

1.00 m

D:S* = Distance to Spot = 392:1
IFOV = Instantaneous Field of View

Reflected

Transmitted

Emitted

terminology—explained

Palette—The palette is the color scheme used to display a thermal image. Whether editing or analyzing, the
objective is to select the palette that best identifies and communicates the problem.

Palette Options (six of 16 available, varies by model)

Ironbow

Check your FOV at
www.fluke.com/fov

Download an emissivity chart at
www.fluke.com/emissivity

Blue-red High contrast

Sensor size—Similar to digital cameras, the sensor size describes the number
of pixels, or measurement points, of a thermal imager. A sensor size of 160 x 120
captures and displays more than 19,000 measurement points with each image, while
a 320 x 240 sensor captures four times as many.

Radiometric—A fully radiometric thermal imager captures not just an image, but
the temperature data for each measurement point within the image. This allows for
greater flexibility in subsequent reporting and analysis.

Field of view (FOV)—The field of view of a thermal imager is determined by its lens,
and defines the area the imager sees at a given moment. The combination of sensor
size, lens, and distance to the measured object will determine the smallest surface
area discernible by your imager. An FOV calculator at www.fluke.com/FOV can easily
help you calculate the measurement surface area at various distances to your target

Thermal sensitivity—Also referred to as NETD (noise equivalent temperature
difference), the thermal sensitivity identifies the smallest temperature difference that
can be measured by the thermal imager. A highly sensitive imager will have a low
NETD and can reveal greater thermal detail in your image.

Emissivity—All objects emit infrared energy, but the level of emission varies
depending on the object’s surface. Emissivity is measured on a scale of 0.0 – 1.0,
and must be matched to the material and surface condition to produce accurate
temperature measurements from your imager. Fortunately, many applications
require only qualitative inspections and don’t require adjusting for emissivity. Visit
www.fluke.com/emissivity for a table showing emissivity measurements for common
surfaces.

Span—The span is the temperature range displayed with the selected palette. A
span that is set too broadly will fail to show subtle temperature gradients within a
captured image. An optimized span will reveal additional detail by displaying more
shades of the palette on the problem area(s).

Amber

Hot metal

Grey

©2009 Fluke Corporation. Specifications subject to change without notice.
Printed in U.S.A. 7/2009 3510697A F-EN-N

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