Optex PT-7LD, Instruction Manual

Page: 44 / 56

10
For the non-contact thermometer (infrared thermometer), the field of view (spot size) is specified
depending on the distance from the thermometer to the measuring object as shown below. The temperature
value displayed is the average temperature within the spot size. To take an accurate measurement, check
the correlation between the size of object and the distance to it.
[Field of View]
* Remarks
ex.) The average temperature of surface of the square 90mm in diameter is measured at a distance
of 3000mm away from the measuring object.
* The laser beam points center of the field of view. The laser marker functions as a sighting method and
not a sensing element.
* It is possible to take temperatures with this thermometer at a distance of 1,000mm or more away from
the measuring object, unless there is any obstacle. However, please note that the measuring field of view
depends on measuring distance. This thermometer has an optical resolution of 33:1
[D(Distance to the measuring object):S(Spot size)].
[For Correct Measurement]
The optical resolution values stated in “Field of View” are at minimum 90% energy. The size of measuring
object should be sufficiently larger than the field of view (spot size) shown in the above illustration.
Please keep away from target as far as you can within spot ratio when you measure high temperature.
Sudden ambient temperature change may cause thermometer display value error. In this case, please
keep thermometer for a while until display value error may be corrected.
Field of View
500
1000
2000
20
30
60
90
D:S=33:1
[Unit : mm]
3000
OK NG
CORRECT
The measuring object is
bigger than the field of view.
INCORRECT
The measuring object is smaller than the
field of view. The temperature of background
influences the measuring value.
Optical Axis/Laser Marker