Novanta SYNRAD Pulstar p100, Руководство пользователя

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OPTICAL ISOLATOR PAGE | 31
laser-based material processing system and each element should be approached with the same careful
attention to detail.
Optical Isolator
An optical isolator is an optical component that allows only the desired linearly polarized light through,
preventing unwanted feedback back into the laser. p100/150 lasers do not have internal isolation. If
isolation is required, an external third-party unit is needed. An optical isolator only works with linearly
polarized light and in conjunction with a (quarter wave) phase retarder. Beam delivery manufacturers
may package the phase retarder and isolator inside one component commonly marketed as a “Beam
Quality Enhancer.” Always double check the system with your supplier to ensure the isolator is present.
When laser processing reflective metals like iron, steel or aluminum, problems can occur if CO2 laser
energy is reflected by the workpiece back through the beam-delivery path and into the laser cavity. Back
reflection can result in unwanted fluctuations of laser power, or even damage the cavity optics inside the
laser. When a reflective material is processed, the use of a back reflection isolator is required.
An optical isolator only works with linearly polarized light and in conjunction with a (quarter wave) phase
retarder. The isolator has to be oriented in a very specific rotational orientation relative to the linear
polarization. Failure to do so will eliminate the protection of the isolator and incorrectly polarized
outgoing lasing energy will not be blocked. Beam delivery manufacturers may package both the phase
retarder and the isolator inside one component commonly marketed as a “Beam Quality Enhancer” or
BQE. For example, the Haas Laser Technology Part Number BQE-25-10.6-SYN incorporates both
polarization and isolation into one housing that can easily be mounted onto the face plate of the laser.
Always double check the system with your supplier to ensure the isolator is present.
Important Note: Optical components in the beam path must always be aligned to the actual
beam path, not the laser faceplate. Because of slight variations in laser construction, the beam
path may not always be centered in, or perpendicular to, the aperture in the faceplate.
Warning: Serious Personal Injury
The long 10.6
µ
m wavelength of CO2 lasers is easily reflected or scattered off metallic surfaces which
can lead to personnel injury and/or damage to equipment.
Enclose the processing area in an interlocked enclosure and ensure proper safety glasses are worn.
Caution: Possible Equipment Damage
Use an optical isolator to protect the laser from damage. Failure to do this, may void the warranty as
equipment damage can occur.