Projection system and method
A light engine. The light engine can include an illumination source that produces light for projecting a still or motion video image. The light engine also can include a condenser configured to receive unpolarized light from the illumination source and output a focused beam of unpolarized light. A polarizing assembly arranged downstream of the condenser can be configured to receive the focused beam of unpolarized light and output substantially polarized light. The polarized light can be directed to a transmissive liquid crystal display panel that receives the substantially polarized light and transmits a video image.
1 . A light engine, comprising:
an illumination source;
a condenser configured to receive unpolarized light from the illumination source and output a focused beam of unpolarized light;
a polarizing assembly configured to receive the focused beam of unpolarized light and output substantially polarized light; and
a transmissive liquid crystal display panel configured to receive the substantially polarized light and transmit a video image.
2 . The light engine of claim 1 , where the polarizing assembly includes a wire grid polarizer.
3 . The light engine of claim 1 , where the polarizing assembly comprises:
a polarizer configured to reflect light of a first polarization and pass light of a second polarization,
a mirror configured to reflect the light of the first polarization reflected from the polarizer, and
a half-wave plate configured to change to the second polarization the polarization of the light reflected from the mirror.
4 . The light engine of claim 3 , where the polarizer is a wire grid polarizer.
5 . The light engine of claim 3 , where the mirror is a metal mirror.
6 . The light engine of claim 3 , where the mirror is a dielectric mirror.
7 . The light engine of claim 3 , where the mirror and the half-wave plate are arranged to combine the reflected light with the light that passes through the polarizer.
8 . The light engine of claim 1 , further comprising one or more integrators optically intermediate the illumination source and the condenser and configured to receive light from the illumination source and output substantially homogeneous, unpolarized light to the condenser.
9 . The light engine of claim 8 , where at least one of the one or more integrators is a fly's eye lens.
10 . The light engine of claim 1 , where light from the polarizing assembly is suitably polarized for delivery to the transmissive liquid crystal display panel without further polarization.
11 . The light engine of claim 1 , where light from the polarizing assembly is suitably polarized for delivery to a liquid crystal display panel without further polarization by an input polarizer positioned intermediate the polarizing assembly and the transmissive liquid crystal display panel.
12 . A light engine, comprising:
an illumination source;
a condenser configured to receive unpolarized light from the illumination source and output a focused beam of unpolarized light;
a polarizing assembly configured to receive the focused beam of unpolarized light and output substantially polarized light; and
a light modulator configured to receive the substantially polarized light and output a video image.
13 . A projector, comprising:
an illumination source;
a condenser configured to receive unpolarized light from the illumination source and output a focused beam of unpolarized light;
a polarizing assembly configured to receive the focused beam of unpolarized light and output substantially polarized light;
a color separating assembly configured to separate the substantially polarized light into separate bands of substantially polarized red light, green light, and blue light;
a first transmissive liquid crystal display panel configured to modulate the substantially polarized red light;
a second transmissive liquid crystal display panel configured to modulate the substantially polarized green light;
a third transmissive liquid crystal display panel configured to modulate the substantially polarized blue light;
a combiner configured to align the modulated red light, green light, and blue light; and
a projection lens configured to project the modulated and aligned red light, green light, and blue light.
14 . The projector of claim 13 , where the polarizing assembly comprises:
a polarizer configured to reflect light of a first polarization and pass light of a second polarization,
a mirror configured to reflect the light of the first polarization reflected from the polarizer, and
a half-wave plate configured to change to the second polarization the polarization of the light reflected from the mirror.
15 . The projector of claim 14 , where the polarizer is a wire grid polarizer.
16 . The projector of claim 14 , where the mirror is a metal mirror.
17 . The projector of claim 14 , where the mirror is a dielectric mirror.
18 . The projector of claim 14 , where the mirror and the half-wave plate are arranged to combine the reflected light with the light that passes through the polarizer.
19 . The projector of claim 13 , where light from the polarizing assembly is suitably polarized for delivery to a liquid crystal display panel without further polarization.
20 . A polarizing assembly, comprising:
a polarizer configured to reflect light of a first polarization and pass light of a second polarization;
a mirror configured to reflect the light of the first polarization reflected from the polarizer; and
a half-wave plate configured to change to the second polarization the polarization of the light reflected from the mirror.
21 . The polarizing assembly of claim 20 , where the polarizer is a wire grid polarizer.
22 . The polarizing assembly of claim 20 , where the mirror is a metal mirror.
23 . The polarizing assembly of claim 20 , where the mirror is a dielectric mirror.
24 . The polarizing assembly of claim 20 , where the mirror and the half-wave plate are arranged to combine the reflected light with the light that passes through the polarizer.