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optoCONTROL 1202
3.
Functional Principle, Technical Data
3.1
Functional Principle
In the laser line sensors of the optoCONTROL series the laser beam of a laser diode
(
l
= 670 nm, 1 mW, power output, laser class 2) is emitted via suitable collimators and apertures as paral-
lel laser light with homogeneous light distribution as laser line from the optical transmitter unit. In the optical
receiver unit the laser line impinges on a CCD line receiver. This CCD line comprises many closely adjacent
individual receiver elements (pixels) that are arranged in a line. The light quantity of each of these receiver
elements that is collected during the integration time can be separately read out as an analog voltage. After
performing analog-digital conversion, it is stored in a data field as a digital value.
When there is a non-transparent measuring object in the laser line, the parallel laser light only illuminates
those receiver elements (pixels) of the line that lie outside the shadow zone of the measuring object. As a
result, the pixels within the shadow zone give off a considerably lower analog voltage compared to the illu-
minated pixels. By means of suitable software algorithms, the areas of the shadow zones can be determined
from the previously stored data field. Since the distance of the pixels on the CCD line is known, size and posi
-
tion of the measuring object can be detected.
The micro controller of the ODC 1202 sensors can be parameterized through the serial RS232 interface by
means of a Windows PC software:
- Setting the evaluation mode
- Setting the output polarity of the three digital outputs
1
(OUT0, OUT1, OUT2)
The housing of the sensor features a TEACH/RESET button
2
and a potentiometer for tolerance setting.
Switching states are visualized by means of 4 LEDs which are integrated in the housing of the receiver.
Two digital inputs (IN0, IN1) make it possible to realize an external TEACH/RESET functionality and an exter-
nal TRIGGER functionality through a PLC.
In addition the receiver features a high-speed analog output (0 ... 10 V) with 12-bit digital/analog resolution.
1) ODC1220 series has two digital outputs (OUT0, OUT1)
2) not available for ODC1220 series
