Page 24 - Lehrbuch Neigungsmessung deutsch 2018.indd

COMPENDIUM INCLINATION MEASUREMENT
WYLER AG, WINTERTHUR / SWITZERLAND

2.8 OPTO-ELECTRONIC PRINCIPLE

A liquid horizontal surface is the basic
reference. Changing the object‘s positi-
on automatically results in changing the
reflection of the sensors optical beam
on the liquid‘s (horizontal) surface. The
reflection is detected by a photo detec-
tor in two axes (X and Y)
1: Liquid
2: Photodetector
3: Source of light

2.9 SEXTANT
A sextant is an instrument used to measure the angle between any two
visible objects. Its primary use is to determine the angle between a celestial
object and the horizon which is known as the altitude. Making this measure-
ment is known as sighting the object, shooting the object, or taking a sight,
and it is an essential part of celestial navigation. The angle, and the time
when it was measured, can be used to calculate a position line on a nautical
or aeronautical chart.

2.10 AUTOCOLLIMATOR
An autocollimator is an optical instrument for non-contact measurement
of angles. They are typically used to align components and measure de-
flections in optical or mechanical systems. An autocollimator works by
projecting an image onto a target mirror, and measuring the deflection of
the returned image against a scale, either visually or by means of an elec-
tronic detector. A visual autocollimator can measure angles as small as
0.5 arcseconds, while an electronic autocollimator can be up to 100 times
more accurate.

2.11 THEODOLITE
A theodolite is a precision instrument for measuring angles in the hori-
zontal and vertical planes. Theodolites are mainly used for surveying ap-
plications, and have been adapted for specialized purposes in fields like
metrology and rocket launch technology. A modern theodolite consists of a
movable telescope mounted within two perpendicular axes — the horizon-
tal or trunnion axis, and the vertical axis. When the telescope is pointed at a
target object, the angle of each of these axes can be measured with great
precision, typically to seconds of arc.

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