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Step 3, Phase measurement: First make sure that auto exposure mode is switched off (Fig. 7), then set the spectral range to the second harmonic (Fig. 8 upper). Then tune the crystal to the correct wavelength by checking the tune to the center of gravity box as an alternative (Fig. 8 lower). You can manually enter the center wavelength and press the tune button. Be sure to reset the exposure time if needed. If you need to further optimize the signal you can adjust the focusing mirror by using the hex key provided with your LX spider. Then, activate the auto-exposure mode and set the spectral range to fundamental. Press the safe save calibration button and when you’re asked to replace the spectrum choose “no”.
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