6 - 1
Cyclops L
Portable Thermometers
User Guide
OPTICS
6
The
Cyclops
has a precision reflex optical system, which provides user-
focusable ‘Through The Lens’ sighting and gives precise definition of the target
spot.
For
Cyclops 100L
,
160L
and
390L
, the specified focal range is 1m/39.4in to
infinity.
For
Cyclops 055L
, the focus is fixed at 5 metres (approximately 15 ft).
6.1 Target Size Calculation for variable focus instruments
This calculation applies to
100L
,
160L
and
390L
thermometers.
The precision reflex optical system gives a narrow field of view (180:1 to 98%
energy). As the instrument is focusable, you can calculate an approximate
target size from the information given in Fig. 6-1.
Target distance (D) from optical datum
Target diameter (T)
Optical
datum
Field of view
Target size (T) (mm) = target distance (D) from optical datum (mm) - 100
field of view (180)
or
Target size (T) (in) = target distance (D) from optical datum (in) - 4
field of view (180)
Fig. 6-1
Cyclops
thermometer target size calculation
