Turn the current control on the power supply to its maximum clockwise position. This will provide maximum laser current. If laser light is produced, tune the rear VERTICAL & HORIZONTAL tuning knobs for maximum power output. If no laser light is seen, continue with the next step.

If laser light is seen at any time during this procedure try to adjust the tuning knobs to maintain lasing.

CAUTION: Hazardous voltages are exposed in the laser head when the cover is removed. The following steps where the laser head cover is removed while the laser is operating should only be performed by an ELC Service Technician or someone trained in the maintenance of  lasers.

3. Turn off the laser, Remove the laser head cover. Pull the laser head cover interlock switch plastic button to the "UP" position or install interlock defeats. This should light or extinguish ( depending on manufacturer ) the "COVERS or Interlock " indicator on the remote control. Restart the laser.

4. Turn the vertical tuning knob at the rear of the laser head counterclockwise 2 turns. This will tilt the mirror tuning plate downward, lowering the axis of reflection of the rear mirror below the center line of the laser bore.

5. Insert a screwdriver blade between the resonator end plate and the mirror tuning plate next to the "Vertical" tuning screw. See Figure 14.

Figure 14.

6. Slowly rock the screwdriver front and back to tilt the mirror tuning plate back and forth repeatedly. While rocking the tuning plate on the vertical axis, slowly turn the "HORIZONTAL" knob one direction for two turns, and then the other for four turns Watch for a flash of laser light during this procedure. If a flash of laser light is observed, immediately stop turning the "HORIZONTAL" knob. The flash of light should repeat every time the tuning plate is rocked. If this happens, remove the screwdriver and slowly turn the "VERTICAL tuning knob clockwise until a steady laser light is obtained.

Once laser light is obtained, refer to "Mirror Walking Procedure," page 44. If no laser light was observed, continue with this procedure.

.7. Remove the interlock cover and unscrew the multiline mirror holder or wavelength selector from the rear of the laser head. Defeat the small interlock by screwing in a small electrical connector next to it to hold it down. Restart the laser.

8. The incoherent blue plasma light will be emitted from the back of the laser. Place a piece of white paper approximately one meter from the back of the laser, so that the light from the plasma produces a circular spot of the white paper. Darken the room lights.

9. Using an allen driver, adjust the vertical tuning screw of the front mirror mount 2 turns counter-clockwise. This screw is accessible through the upper right hand hole in the front bezel. Now perform steps 5 and 6 of this section on the front mirror plate. However, instead of watching for a flash of laser light, watch for a small spot of light which is slightly more brilliant than the large spot. The small spot will be within the area of the large spot. As the mirror mount is rocked, the small spot (Figure 15) will be observed to be going up and down through the larger spot of light. This smaller spot should be adjusted (via the front mirror mount tuning screws) to the position where it is of the maximum intensity (this may or may not be in the direct center of the larger spot of light). This small spot of light is the reflection of the plasma light shining on the front mirror and then being directed through the laser bore to the white card. This insures a rough alignment of the front mirror. Do not adjust the front mirror mount tuning screws further.

White card or paper

Figure 15.

10. Reinstall the multiline mirror holder or wavelength selector.

11. Reinstall the interlock cover.

12. Repeat steps 4, 5, and 6 of this section at the rear to produce lasing.