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Functional Principle, Technical Data
optoNCDT 1402
Functional Principle, Technical Data
3.
Functional Principle
3.1
The sensor uses the principle of optical triangula-
tion, i.e. a visible, modulated point of light is pro-
jected onto the target surface.
The diffuse element of the reflection of the light spot
is imaged by a receiver optical element positioned
at a certain angle to the optical axis of the laser
beam onto a high-sensitivity resolution element
(CCD), in dependency on distance.
The controller calculates the measured value from
the CCD-array. An internal closed-loop control
enables the sensor to measure against different
surfaces.
A LED on the sensor indicates:
In range
-
Out of Range (upper and lower range values),
-
poor target (unfit or no object)
Mid range
-
Measuring range SMR
4 mA (SMR)
161
12 mA (MR)
8184
20 mA (EMR)
16207
3.75 mA
16374
Current
Digital
output
value
laser on
state
teach in
optoNCDT
3.75 mA
16372
LASER RADIATION
Do not stare into the beam
CLASS 2 LASER PRODUCT
IEC 60825-1: 2007
3P:
O
=670 nm
Definiton of terms, output signal
Fig. 2:
SMR = Start of measuring range | MR = Midrange | EMR = End of measuring range
Functions
3.2
Fitting the Measurement Range
3.2.1
The analog measuring range can be reduced with aid of the “Teach“ function, see Chap. 6.2. This enables
you to scale only a part of the measuring range to the full scale current output. Thus the resolution of analog
evaluation systems like displays or PLCs will be used better.
