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Functional Principle, Technical Data
confocalDT 24x1
2.
Functional Principle, Technical Data
2.1
Short Description
The confocalDT 2451/2461/2471LED
measuring system includes
The confocalDT 2471
measuring system includes
-
one sensor,
-
one controller IFC2451, IFC2461
or IFC2471LED
-
one optical fiber (optic cable).
-
one sensor,
-
one controller (IFC2471) for the external
light source,
-
one Xenon light source (IFX2471),
-
two optical fibers (optic cable).
The external light source IFX2471 is required to operate the controller IFC2471 at high
measuring rates. The controller IFC2451, IFC2461 and IFC2471LED comes with an inte-
grated white light LED as an internal light source.
The sensor is completely passive as it contains no heat sources or moving parts. This pre-
vents any heat-related expansion, and ensures high precision of the measuring system.
The external light source feeds the sensor through the controller. The controller uses a
spectrometer to convert any light signals that it receives from the sensor. It then calculates
distance values using the integrated signal processor (CPU) and transfers the data via its
interfaces or analog outputs.
CPU
External light source
Spectrometer
DA converter
Optical fiber
RS422 and
Ethernet /EtherCAT
Analog output U / I
Xenon light source
Sensor
IFX2471
IFC2471
Controller
Fig. 1 Block diagram confocalDT 2471
2.2
Measuring Principle
The sensor projects polychromatic light (white light) to the target surface. The sensor
lenses are designed to use controlled chromatic aberration to focus each light wavelength
at a specific distance. In reverse, the sensor will then receive the light that is reflected from
the target surface and transfer it to the controller. This is followed by the spectral analysis,
and then the data stored in the controller are used to calculate the distances.
i
Sensor and controller are one unit, as the sensor's linearization table is stored in the
controller.
This unique measuring system allows for highly precise measurement of applications.
It is possible to measure both diffuse and reflecting surfaces. For transparent layered
materials, thickness measurements can be conducted in addition to distance measure-
ments. Shadowing is avoided because sender and receiver are aligned along one axis.
The excellent resolution and the small beam spot diameter make it possible to measure
surface structures. However, measurement deviations may occur if the structure is of
a similar size to the beam spot diameter or if the maximum tilt angle is exceeded (for
example, with groove edges).
