HP 5528A

Model 5528A
Straightness Measurement s
11-14
5. Orient the Re tr orefle c tor 50 the I nterfe rometer lines up with the ce nter of the Reflector's
slotted
opening and the top half of the Re tr oreflector is exposed to the la se r beam that will
come
from the ot her si de of the Straightness Reflector.
Fa sten the Re lr orefle c tor to the machine in such a way that the Interferometer is as square as
possible 10 the Refle clO r and to the incoming beam. The I nterfer ometer hous ing' s pilch
limitations are ±2 degre es; its yaw and roll limitations arc ±5 de.grees. The pitch and yaw
requirements will
be taken care of aUlOrnatically by using the Straightness R el r or ef lector and
an HP Post.
6. Position the Reflector relative to the Re lr or cflector and I nterfer ometer.
Bring the I nterfer o meter / Re tr orefle c tor a ssem bly close enough to the Straightness Reflector
to
line up t he I nterfer ometer with the juncti on of the Reflec tor 's mirrors.
Also
po s ition the I nterfer o meter in the other axis so its opening is po sitioned in the ce nt er of
the Reflecto r' s slot. ( look straight into the Reflec tor and make sure the Interferometer 's
opening is in the midd l e. )
This is
a very important step. If the Opti cs are not physically lined up at thiS point, aligning
along the
travel axis will be impo ss ib l e.
Be sure this establishes the "n ear end of travel", i.e., that any later movement of the ma chine
ca n only increa se the di stance between the Opti cs.
7. Make s ure the Reflec tor is square relative to the ma chine and to the Interfer ometer ( within
±5 degrees). and then se cure the Reflector to the ma chine.
8. Switch to the large aperture on the laser Head's exit port, and set the turret ring to "O THER ".
( When aligning your se l up it is good practice to work with the strongest p oss ible beam,
which thi s selling provides.).
9. Visual ly align the L ase r Head as well as you c an pa rallel 10 the ma c hine' s table, and p osi tion it
to have the beam go over the Straightne ss Reflec tor and through Ihe Re lro reflec tor 's
Al ignment ring. (See Figure 11-6. )
10 . Orient the I nterf ero meter bezel's sc ribed line 90 degrees to the Reflec tor' s s lotted opening.
Tw o dots s hould appear on the Reflector 's fronl surface unl ess the Opti cs are quite close
together. (
See Figure 10-6.) If so, in se rt a piece of paper ac ross the front of the Straightn ess
Refl ector to see the dots.
11. Further adjust the Reflec tor 's position until the two dot s are directly in line with the junction
of the Reflector 's mirrors and are also sy mmetri cal ab out its slol1ed op ening.
12 . Sec ure the Reflector assembly to the rnachine, if you had to move it in step " 11 ".