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 OMC elog Not logged in  Mon Feb 4 00:39:08 2013, Koji, Optics, Characterization, Wedge measurement with the autocollimator and the rotation stage  Wed Feb 6 02:34:10 2013, Koji, Optics, Characterization, Wedge measurement with the autocollimator and the rotation stage Fri Mar 1 23:52:18 2013, Koji, Optics, Characterization, Wedge measurement with the autocollimator and the rotation stage
Message ID: 59     Entry time: Mon Feb 4 00:39:08 2013     Reply to this: 60
 Author: Koji Type: Optics Category: Characterization Subject: Wedge measurement with the autocollimator and the rotation stage

Method:

• Mount the tombstone prism on the prism mount. The mount is fixed on the rotation stage.
• Locate the prism in front of the autocollimator.
• Find the retroreflected reticle in the view. Adjust the focus if necessary.
• Confirm that the rotation of the stage does not change the height of the reticle in the view.
If it does, rotate the AC around its axis to realize it.
This is to match the horizontal reticle to the rotation plane.
• Use the rotation stage and the alignment knobs to find the reticle at the center of the AC. Make sure the reticle corresponds to the front surface.
• Rotate the micrometer of the rotation stage until the retroreflected reticle for the back surface.
• There maybe the vertical shift of the reticle due to the vertical wedging. Record the vertical shi
• Record the micrometer reading. Take a difference from the previous value.

Measurement:

• A1: α = 0.68 deg, β = 0 arcmin (0 div)
• A2: α = 0.80 deg, β = -6 arcmin (3 div down)
• A3: α = 0.635 deg, β = -1.6 arcmin (0.8 div down)
• A4: α = 0.650 deg, β = 0 arcmin (0div)
• A5: α = 0.655 deg, β = +2.4 arcmin (1.2 div up)

Analysis:

• \theta_H = ArcSin[Sin(α) / n]
• \theta_V = ArcSin[Sin(β) / n]/2

• A1: \theta_H = 0.465 deg, \theta_V = 0.000 deg
• A2: \theta_H = 0.547 deg, \theta_V = -0.034 deg
• A3: \theta_H = 0.434 deg, \theta_V = -0.009 deg
• A4: \theta_H = 0.445 deg, \theta_V = 0.000 deg
• A5: \theta_H = 0.448 deg, \theta_V = 0.014 deg

 Attachment 1: autocollimator_wedge_measurement.pdf  69 kB  Uploaded Tue Feb 5 01:29:33 2013 ELOG V3.1.3-