Figure 3-18.--Typical cell calibration setup (overhead view).

Figure 3-18.--Typical cell calibration setup (overhead view).

Figure 3-19.--Cell focusing measurements.

maintaining a weather seal to keep moisture, dirt, and so

regulation in the lens compartment. These are discussed

on from entering. Cool air is drawn in through the rear

in the following paragraphs.

louver by the blower fan, and exhausts through the side

louver after absorbing heat radiated by the projection

Projection Lamp Compartment Cooling

lamps.

The three projection lamps used in the GSI generate

Lens Assembly Temperature Control

large amounts of heat when they are operated at full

intensity. Cooling of this compartment is accomplished

Temperature control of the Fresnel/lenticular lens

by a blower/louver arrangement. A special design louver

assembly is located on each side of the projection lamp

assemblies is important to prevent lens distortion fog-

ging, or other environmental reactions. In the GSI, lens

shroud This design allows entry of cooling air while

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