OPHIR BeamSquared - Page 49

After Lens
After Lens results are the computed results for the laser beam propagation after the lens. These properties
are referred to as the “artificial results” since they only apply to the focused beam propagating in the 2 space.
These items are:
Divergence
Θ
0
The artificial far field divergence.
Waist Width
W
0
The artificial waist width.
Waist Location
Z
0
The artificial waist location measured from the lens.
Rayleigh Length
Z
R
The artificial Rayleigh length of the focused laser.
Astigmatism
Ast
A computed ratio indicating the degree to which the artificial laser X and Y waist
properties exhibit astigmatic behavior.
Asymmetry
Asy
A computed ratio of the artificial X and Y waist widths.
Twist
When a Beam Twist measurement is taken, it looks at Ellipticity first and then
Orientation. If the Ellipticity is greater than 87% the beam is considered circular by
ISO standards, and Beam Twist is not measured. If Ellipticity is less than 87% then
the Beam Twist is measured by the degree of the change in Orientation.
The Beam Twist result is a pass/fail result. If it is greater than 10° the result turns red
and the laser results do not meet ISO specifications.
Ellipticity
Only active when Beam Twist is active. The computed ratio of the major and
minor beam widths of an elliptical beam. Beams with Ellipticity greater than 87%
are considered circular by ISO standards.
Orientation
Only active when Beam Twist is active. The angle between the horizontal axis of
the camera, and the major axis of an elliptical beam. Can be negative or positive.
Beam Twist
The rotational change in orientation for an elliptical beam.
Hardware Settings
The Hardware Settings group displays information about the BeamSquared system and lens in use when
the data was obtained. These are for reference only.
Z Lens
The calibrated Z
lens
distance of the BeamSquared unit.
Z Fixture
The calibrated Z
fixture
distance of the BeamSquared unit.
Z Camera
The calibrated Z
cam
distance of the BeamSquared unit.
Effective Focal Length
The wavelength-corrected focal length of the lens.
Back Focal Length
The calibrated back focal length value of the lens at the calibration wavelength.
Center Thickness
The center thickness of the lens.
Lens Material
The substrate of the lens.
Calibration Wavelength
The wavelength used to calculate the calibration focal length of the lens.
Calibration Focal Length
The calibration focal length of the lens at the calibration wavelength.
BeamSquared Serial
Number
The serial number of the BeamSquared unit.
Laser Model
The user-entered laser model information. This value can be changed in the Run