HP 5528A User Manual

Model 5528A
Alignment Techniques
15-4
OVERLAPPING DOTS METHOD
This alignment method is u se d only for Di sta nce or Velocity measurement s.
Description
The "Ove rlapping Ool s" method is identi ca l 10 the "Gunsight" method, except that the Inter-
ferom e ter and Retroreflecl or largets are removed and the La se r Head return pori becomes the
target.
Procedure
1. Install the Optics as described in Section 6 of this Use r 's Guide ( "0 1 5T ANCE MEASUREMENTS ").
The
return beams from yo ur Distance Opti cs should co mp letely overlap on the la se r Head 's
lo wer (return) port. The Optics sho uld be at the "near end of travel" ,
NO TE
You should not ha ve targets in plac e.
2. Move the Ret r oref lector away from the la ser (or se parate the Optics).
If the La se r is not aligned to the travel axis, the Retroreflector dot will begin to move from the
target
port . The dot will move until the beam is cut off by the edge of the Interferometer 's
window, Stop mo ving the Retroreflector before the beam is thus blocked, or when the end of
travel is reached. Fi g ur e 15 -2 shows why the re turn dot moves .
LAS ER
LA SE R A XIS
'\ _ _ _ TRAVEL AX,S
RETROFLECTOR
--_ . ~--
INTERFEROMETE R
DI
SP LACED RETR OREFLECTOR BEAM
Figure 15 -2. Relroreflec!or Movemen/
This step is identi ca l to the "G uns ight" alignment method 's step "2", ex cept that you must
l ook at the La se r H ead instead of the tar gels on the opti cs.
Fi g ure 15 -3 illustrates a typical two -dot pattern that you may see after the opti cs mov e,

HP 5528A Specifications

General

Brand	HP
Model	5528A
Category	Measuring Instruments
Language	English