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LRF 3013 Integrator Manual
If such equipment is not available, an alternative method can be used to show
the path of the invisible laser light. Place a vertical and horizontal small pole
(approx. 10 cm of width) at several hundred meters distance. Start with one
orientation (horizontal or vertical) and measure until the laser hits the pole
and gives the correct distance back. You can then center the laser to this first
orientation and then do the same with the second orientation. With this
method you can align the laser to any equipment, however its more time
consuming and not as precise as with a camera.
A quick and easy tool to make laser light visible are laser viewing cards. Those cards have a
photosensitive area which emits a visible spot at the location of the laser beam. However, this only works
when the card is quite close to the LRF module. To see the laser beam of LRF 3013 modules, the laser
viewing card must absorb light of 1550 nm wavelength. Vendors of such cards are:
Laser2000 (www.laser2000.de) (e.g. QTX-Q42-T)
Thor Labs (www.thorlabs.de) (e.g. VCR4)
Please see the mechanical ICD in the appendix 9.2 to determine the required mechanical tolerances for
alignment.
4.2.4
Nitrogen flushing
To avoid condensation of humidity in the optical system, the module is recommended to be operated in a
'dry' atmosphere inside a housing. Several ventilation holes may be provided in the mechanical system
holding the optics, which are covered by small pieces of tape. The pieces of tape are intended to avoid
dust penetrating the optical system and should be removed just before the application is sealed and
purged. With respect to dust, the unit is recommended to be handled observing standard practices for
sensitive optical components and assembly procedures.
4.3 Front Protection
The LRF module itself is not gas tight. Therefore implementing an LRF module into a host system
requires a protecting environment with a protective window in front of the LRF module.
The laser diode emits laser light towards the objective lens. This lens sends out a mainly parallel beam,
with some angular spread called beam divergence.
Care has to be taken, that there is no substantial absorption of the laser energy at 1'550 nm wavelength.
Standard optical quality glass should be used, the material of the window needs to be transparent for the
1'550 nm wavelength (i.e. BK7 from Schott).
The antireflection coating of the window is recommended to be "broadband", in other words, effective for
visible light as well as for the laser wavelength. Choosing a narrow band must also allow the transmission
of temperature shifted laser light (e.g. 1'550 nm = 1'500 ...1'600 nm depending on temperature).
If the coating reflects visible light, one will not see inside the LRF module, which is not a problem, but it
can appear like a mirror and reflect a lot of sunlight.
The coating should fulfill the following specs:
visible light: R < 1 % for lambda = 420 ... 650 nm, light angle 0°+/- 15°
If this is not fulfilled, you have an optical mirror. However, it is the decision of the system
integrator to specify transmission for visible light of the front windows.
laser light: R < 0.5 % for lambda = 1'500 ...1'600 nm, light angle 0°+/- 15°
If this is not fulfilled, the laser energy is reduced and internally reflected. This can cause optical
cross talk and lead to incorrect or no measurement results.
Document number: TML 913655 ver A
Confidential & Proprietary Safran Vectronix AG – All rights reserved
Figure 9: Boresighting
Public: 13.03.2017
page: 19/36
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