LASER LEVEL TRANSMITTER
The laser level transmitter either uses
triangulation, time of flight or confocal chromatic working principle
Triangulation
One method for accurately measuring the distance to targets is
through the use of laser triangulation sensors. They are so named because the
sensor enclosure, the emitted laser and the reflected laser light form a
triangle.
The laser beam is projected from the instrument and is reflected from a
target surface to a collection lens. This lens is typically located adjacent to
the laser emitter. The camera views the
measurement range from an angle that varies from 45 to 65 degrees at the centre
of the measurement range, depending on the particular model.
Time of flight
This technique uses the
time light takes to travel to a target and back, but the time for a single
round trip is not measured directly. Instead, the strength of the laser is
rapidly varied to produce a signal that changes over time. The time delay is
indirectly measured by comparing the signal from the laser with the delayed
signal returning from the target.
Confocal chromatic:
This uses use a white light source to accurately
measure the distance to surfaces. The essence of our confocal chromatic imaging
principle is the accurate
detection of colours from light that is reflected back from target surfaces.
The white light is focused onto the target surface by a multi-lens optical
system. These lenses disperse the light into monochromatic stages (colours) along
the measurement axis. A specific distance to the target is assigned to each colour’s
wavelength in a factory calibration. Only the wavelength which is exactly
focused on the target is used for the measurement. This light reflected from
the target surface is transmitted from the probe, through a confocal aperture
and onto a spectrometer which detects and processes the spectral changes and
calculates distances. These distance measurements are transmitted at high speed
via Ethernet communications protocol.
Some of the laser LT are below
