Barco F70 Service Manual page 23

DLP System General Description
Image 4-2
The phosphor absorbs the blue laser light, and emits a broad band yellow light which is reflected back towards
the dichroic mirror, where it is transmitted, and focused onto the dual rod system.
A small portion of the blue light is transmitted through a clear segment of the PW, and is relayed around to the
back of the dichroic mirror. There it is reflected a second time and combined with the yellow light from the PW
before it is focused on the dual rod system.
The dual rod system consists of two solid integrating rods (one for each illumination path) and a hollow
integrating rod combining the two seamlessly. This exit surface is imaged onto the DMD using traditional relay
optics and TIR prism.
To create Red and Green color, a color wheel is placed after the hollow rod exit surface, which is synchronized
with the PWs in each illumination path. This is again synchronized with the DMD producing time sequential
Red, Green and Blue colors on the wall perceived by the human eye as white light.
By using the internal illumination iris the contrast ratio can be increased, and by sliding in the motorized color
filter (located next to the iris) a broader color gamut can be achieved.
Use only ionized pressurized air while cleaning and servicing optical components.
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