JVC Model 200 service manual Prism Assembly

Chapter 4---Maintenance (Removal/Replacement)

NOTE: When changing from a zoom to a fixed lens, or vice versa, the ILA® Back Focus (Section 3.4) may need readjustment.

4.18 Prism Assembly

CAUTION! The removal of the Prism Assembly requires removing the Dichroic Mirror Assembly (X-Plate). In most cases this necessitates an optical realignment. HJT does not recommend performing this replacement in the field. Optical alignment is critical and requires projector power to be on. This results in an additional safety hazard due to the high intensity light beam emanating from the optical area with the optical cover off. If removal and replacement is absolutely necessary, proceed with extreme caution and wear safety glasses.

The Prism Assembly requires the removal of more components and assemblies than any of the other assemblies. Be sure to have storage cabinets or tables to house the various items as they are removed to provide access to the Prism Assembly. Allow about 3-4 hours to perform the removal and replacement of the Prism Assembly. Refer to Figures 4-1 and 4-11 for the assemblies referenced in this procedure.

To remove the Prism Assembly:

1.Remove front and rear covers (Section 4.2).

2.Remove the Optical Shield by removing the 3 screws holding it.

3.Remove the Arc Lamp air filter and cover (3 screws).

4.Remove the Arc Lamp (Section 4.4).

5.Remove the Lamphouse Dock (Section 4.4).

6.Remove the lower right side panel (5 screws).

7.Remove the X-Plate (Dichroic Mirrors) assembly by removing the four hex bolts securing it (see Figure 4-14). CAUTION! Use care when lifting the mirror assembly. Place it in a safe, level storage area.

Model 200 Service Manual 4-21