Datasheet

= IR thermometer
field of view
Smaller target
Manufacturer
recommended
large target
IR thermometer
spot size
199.3
Infrared
thermometers
have
peripheral
vision.
Common pitfalls in infrared thermometer calibration
How to get consistent
results:
Even those infrared thermom-
eters that cannot be adjusted can
benefit from a calibration that
demonstrates the consistency and
validity of your results. A trusted
calibration means less worry,
fewer questions and more time
being productive. To get more
reliable, traceable, and consistent
results, buy a precision infrared
calibrator from Fluke Calibration.
The 4180 Series of Precision
Infrared Calibrators for infrared
thermometers and thermal imag-
ers is fast, accurate, and easy to
use. It comes with an accred-
ited calibration from one of the
world’s most trusted temperature
calibration laboratories, sample
calibration procedures for Fluke
thermometers built right in and
everything you need to get started
making high-quality infrared ther-
mometer calibrations. This is the
perfect solution for any infrared
thermometer or thermal imager
within its temperature range.
The 4180 reaches temperatures
from –15 °C to 120 °C and the
4181 has a temperature range
from 35 °C to 500 °C. Check
out the uniformity of the large
152.4mm (six in) targets shown
in the Fluke Ti30 photo. The uni-
formity and stability are so good
that variations can’t be detected
with a thermal imager. Uniformity
is important in infrared tempera-
ture calibration work because an
infrared thermometer will “see”
as much as the entire target
when placed at the appropriate
calibration distance and each
pixel of a thermal imager regis-
ters a temperature that needs to
be both accurate and consistent
across the imager.
In addition, with accuracies
as good as ± 0.35 °C, the 4180
Series can meet its specifications
without additional emissivity-
related corrections, leading to
legitimate test uncertainty ratios
(TUR) as good as 4:1. (See the
sidebar below for information
about common pitfalls in infrared
calibrator accuracy and have a
look at our Guide to Infrared Ther-
mometer Calibration
to get started quickly with your
new calibrator.)
3 Fluke Calibration 4180 Series Precision Infrared Calibrators
• If the target size is too small, the thermometer will
not read the right temperature. This problem, called
size of source effect, is addressed by the large,
152.4 mm (six in) target of the 4180 series, which
was designed to accommodate the field of view
and calibration geometry requirements of certain
common infrared thermometers used in the field, lab
and process control.
• Some people are misled by the accuracy statements
on IR calibrators because they are not familiar with
the concept of emissivity. Look for calibrators with
a “radiometric calibration” so that accuracy will be
straightforward and uncomplicated by emissivity-
related errors.
For more information on emissivity, size of source effect
and radiometric calibration, see Fluke Calibration appli-
cation note “Infrared Temperature Calibration 101” or
choose a calibrator like the 4180 series that you know
has already addressed all of these issues.