What
is infrared thermography?
-
Infrared is an invisible portion
of the light spectrum extending from 0.75 to 1000 microns. All objects
warmer than absolute zero (0 Kelvin or -275.15ºC) emit energy somewhere
within that range. The warmer the object, the brighter we see it with an
infrared thermal imager. In raw infrared white is hotter, black is colder.
What is a thermographer?
-
A thermographer is a thermal evaluator
and imaging expert. He or she will have a solid understanding of heat transfer
laws, thermal dynamics and properties of materials. Knowledge of objects
and why they appear hot or not. Thermography is not just white is hot and
black is cold because of outside factors that a thermographer must know
thoroughly.
-
A thermographer is a person who
uses an Infrared camera and his / her knowledge of the subjects they look
at in combination with other non-evasive testing tools to evaluate the
condition. Thermography is not a 9 to 5 job... There are so many areas
the same thermal expert can be involved in, with the exact same thermal
camera, it offers diversification like no other career...
What is an infrared thermometer ( point radiometer
)?
-
An infrared radiometer (sensor)
provides a remote temperature measurement of an object without touching
it. The sensor measures the amount of infrared energy emitted from an object
and converts this to a digital temperature readout. With
a point radiometer you have no image to analyze what or where the problem
is precisely located. Also a thermometer / radiometer averages a spot size
depending on the range from the object(s).
What is a radiometric infrared thermal imager?
-
A radiometric infrared thermal
imager is a device that makes an image of the thermal patterns and is calibrated
to take temperatures in a small area at various ranges.
Can the object being measured be moving?
-
Yes. Measuring moving targets
is one of the benefits of using non-contact infrared thermometry.
How close do I have to be to an object to take
its temperature?
-
With a radiometric infrared imager temperatures can
be read at great distances with digital magnification. In most modern focal
plan array radiometric imagers, atmospheric conditions effect the amount
of infrared energy that is detected. Some imagers have software onboard
to compensate for this phenomenon called absorption.
Does color effect infrared measurement?
-
In some cases it does however,
a different surface characteristic, called emissivity, greatly effects
the infrared image and temperature. Emissivity is a function of both the
type of material you are measuring and its surface finish. This is primarily
a concern for metallic materials. Most sensors can be adjusted by simply
pushing a button or changing settings on a computer screen of the known
emissivity.
Can infrared instruments measure water or ice?
-
Yes, as mentioned above, an object
warmer than absolute zero emits energy. (But infrared "reads" surface
temperatures.)
Will infrared instruments measure air?
No, an infrared thermometer
needs a surface to measure. In fact, most infrared instruments are specifically
designed so that the air between the sensor and the target does not effect
measurement.
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1999 - 2001 Infrared Services, Inc. All rights reserved.