SICK LMC121, Руководство по эксплуатации

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Operating Instructions
LMS1xx Laser Measurement Sensors
Product description
8012471/ZN27/2017-06-09 © SICK AG · Germany · All rights reserved · Subject to change without notice
31
Chapter 3
Example for angular resolution 0.50° in Fig. 18 on page 30
Distance 35 m
Distance intersection point 35 m gives a distance between the measured points of approx.
305 mm.
Distance intersection point 35 m with the characteristic curve for beam diameter gives a
beam size of approx.
560 mm.
3.6.3 Minimum object size
To reliably detect an object, a laser beam must be fully incident on it once. If the beam is
partially incident, less energy will be reflected by an object than necessary in some circum-
stances (see
Fig. 10 on page 25 ).
An object is only reliably fully seen if it is at least as large as the measured point spacing
plus the beam diameter.
Fig. 19: Minimum object size for detection
In the example in Fig. 19 , the beam is fully incident on the object at least once during each
scan. It will therefore be reliably detected if it has the necessary remission.
How to calculate the minimum object size:
beam di distance between the measured points = minimum object size
 For beam diameter and measured point spacing as a function of the distance from the
LMS1xx see the diagram in
Fig. 16 on page 29 .
Important In particular on the usage of the LMS1xx for measured value output, it is necessary for a
reliable measurement that the beam is incident on the object several times. The example
shows the minimum size of an object. For a reliable measurement it is important that the
beam is incident on the object several times. Therefore an object should be either larger
than the minimum object size or the LMS1xx as well as the object should not move.
Scan 1
Scan 2
Scan 3
Beam diameter
Distance between measured points