HP 5528A User Manual

Model 5528A
S lr a ightn ess Mea s urement s ( Along A Horizontal Axis)
10-24
Environmental Errors
Description
As with any ac curate measurement, and in particular with all la ser Sys tem measurements, the
environment pla
ys a ve ry important role.
Environmental
errOrS corne from -
1.
Thermal expansion of the ma chine or part,
2. Ma chine vibration,
3. Air
turbulence.
A Straightness meas ur ement is especially su sce ptible to environmental effects. It is imp oss ible to
quantitatively determine
how these environmental c hara cteri st i cs will affect the m eas urement,
although it is sometimes
possible to identify when th ey are ha ving an effect.
Excessive vibration and/ or air turbulence ca n be identified by -
1. Random
drifting of the measurement results when the Optics are at rest.
2. Drifting increa si ng as the distance between the Optics increa ses.
The effects of vibration ca n be further identified if the drifting of the mea surement SlOpS when the
ma chine is turned of(, or by e)(cee ding the slew rate during the mea su rcment ( di srupting the
measurement
).
Minimizing Eff ects
1. Thermal expansion of the machine or Optics.
These effects ca n be minimized by Ictting the machine and Opti cs reach thermal e<luilibrium
before making a m eas urement.
2. Machine Vibrations.
it . Adequate fixturing is the ma in way to reduce the effects of vibration.
Make s ur e the Straightn ess Reflector 's Ba se is sec urely fastened 10 the tabl e, and that the
Po st is secu rely fastened to the b ase on one end and the R efleao r on the OIher.
Avoid
long ex tensions.
b.
Vibrational effe cts c an also be reduced by -
• Averaging su ccess i ve runs or averaging su ccess i ve ave rag es.
• More accurale manual s lop e rem ova l.
• Reduced feed rales.
•
Pad s under the refl edo r 's b ase as a la sl resort in high-vibration, low-accu ra cy work.

HP 5528A Specifications

General

Brand	HP
Model	5528A
Category	Measuring Instruments
Language	English