Appeal No. 2003-1551
Application No. 09/550,713
wavelength delay reads on quarter-plate 27 and reflecting plate
28. Since beam Ls goes through quarter-plate 27 twice, a half
wavelength delay is created. A direction-modifying means reads
on prism 29 which changes the direction of beam Lp so that it is
parallel to the reflected S polarized light wave. Mitsutake does
not disclose a condenser for condensing the reflected S polarized
light wave and the transmitted P polarized light wave, but the
admitted prior art in Figure 1 of appellant’s application shows
that it is conventional in a projection-display system for a
condenser 15 to be used for condensing the S and P polarized
light waves. It would have been obvious to the artisan to
condense the S and P polarized light waves of Mitsutake for use
in a projection-display system as taught by the admitted prior
art.
The remaining portion of claim 1 recites that the PBS-
and-delay device (PDD) comprises an “integrally-formed” element.
Mitsutake teaches that the total reflection prism 29 may be
integrally formed with a rectangular prism, positioned next to
the total reflection prism of the polarizing beam splitter (PBS)
[column 7, lines 5-8]. We interpret this portion of Mitsutake as
suggesting to the artisan that the optical elements making up the
device of Figure 5 can be integrally formed. Therefore, we find
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