Agilent Technologies 5530, Getting Started Manual

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Chapter 8 Ensuring Repeatability, Accuracy, and Resolution
Ensuring Accuracy
8-8 Getting Started Guide
8
Figure 8-4. Example of cosine error
To minimize cosine error, follow these guidelines:
• Take time to carefully check your optic alignment to ensure the laser
beam is traveling parallel to the machine travel.
• Watch for irregularities in your linear measurements. If the amount of
error is steadily increasing, you may have significant cosine error.
• Allow the temperature of the optics to stabilize before making the
measurement (approximately 5 to 10 minutes).
1
Laser head
2
Interferometer
assembly
3
Retroreflector at the
first measurement
position
4
Displacement along
the axis of
measurement
5
Retroreflector at the
second measurement
position
6
Axis of motion
7
Axis of measurement
8
Actual displacement
0
1
2
3
4
5
6
8
7