1. An exhaust emission control device comprising:
a porous filter body through which exhaust gas passes and which is configured to capture particulates entrained in the gas;
a first electric heater that heats the filter body to thereby provide a heat regenerative particulate filter, said heat regenerative particulate filter being accommodated in a filter casing within an exhaust pipe,
a second electric heater disposed downstream of the particulate filter; and
upstream and downstream oxidation catalysts arranged upstream and downstream, respectively, of and adjacent to the particulate filter in the filter casing so as to provide a thermo-keeping effect to the particulate filter, wherein
the exhaust gas arbitrarily bypasses the filter casing,
the filter body has a plurality of passages in the form of a honeycomb through which the exhaust gas passes, inlets and outlets of the respective passages being alternately plugged,
said first heater is upstream of the particulate filter and downstream of the upstream oxidation catalyst, and
the second heater is upstream of the downstream oxidation catalyst.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An illuminator which emits trichromatic light including components whose wavelengths correspond to three primary colors, respectively, the apparatus comprising:
a light source to emit the trichromatic light; and
a wavelength-selective optical aperture filter provided at the side of the light source from which the trichromatic light goes out and which consists of zones working as predetermined optical apertures, of which one selectively attenuates or shields a component of the trichromatic light, whose wavelength corresponds to at least one of the three primary colors, while the other zones allow the light components whose wavelengths correspond to the other primary colors to pass through.
2. The apparatus as set forth in claim 1, wherein the zones of the wavelength-selective optical aperture filter correspond to the component of the trichromatic light, having a wavelength corresponding to the red, green or blue of the three primary colors.
3. The apparatus as set forth in claim 1, further comprising a pair of fly-eye lenses formed from a plurality of lens elements, being provided along the outgoing direction of the trichromatic light from the light source, and which separates the trichromatic light emitted from the light source into primary-color light components and allows the separated primary-color light components to pass through the a plurality of lens elements, thereby uniformizing the trichromatic light output,
the wavelength-selective optical aperture filter being provided adjacent to one of the pair of fly-eye lenses that is farther from the light source.
4. The apparatus as set forth in claim 3, wherein:
one of the main surfaces of the pair of fly-eye lenses that is farther from the light source is formed flat; and
the wavelength-selective optical aperture filter is formed on the flat surface of the fly-eye lens farther from the light source.
5. The apparatus as set forth in claim 3, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the lens elements of the pair of fly-eye lenses.
6. The apparatus as set forth in claim 1, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the light components whose wavelengths correspond to the three primary colors: red, green and blue, respectively.
7. The apparatus as set forth in claim 1, wherein:
the light source is a metal halide lamp or ultra-high voltage mercury lamp; and
the zones of the wavelength-selective optical aperture filter attenuate or shield the light components whose wavelengths correspond to the green andor blue.
8. An illuminator which emits trichromatic light including components whose wavelengths correspond to three primary colors, respectively, the apparatus comprising:
a light source to emit the trichromatic light;
a pair of fly-eye lenses each formed from a plurality of elements and which separates the trichromatic light emitted from the light source into primary-color light components and allows the separated primary-color light components to pass through the plurality of lens elements, thereby uniformizing the trichromatic light output; and
a wavelength-selective optical aperture filter provided adjacent to one of the fly-eye lenses that is farther from the light source and which consists of zones working as predetermined optical apertures, of which one selectively attenuates or shields a component of the trichromatic light, whose wavelength corresponds to at least one of the three primary colors, while the other zones allow the light components whose wavelengths correspond to the other primary colors to pass through.
9. The apparatus as set forth in claim 8, wherein the wavelength-selective optical aperture filter has the zones formed at random correspondingly to the lens elements of the fly-eye lenses.
10. The apparatus as set forth in claim 8, wherein:
one of the main surfaces of the pair of fly-eye lenses that is farther from the light source is formed flat; and
the wavelength-selective optical aperture filter is formed on the flat surface of the fly-eye lens that is farther from the light source.
11. The apparatus as set forth in claim 8, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the lens elements of the pair of fly-eye lenses.
12. The apparatus as set forth in claim 8, wherein:
the light source is a metal halide lamp or ultra-high voltage mercury lamp; and
the zones of the wavelength-selective optical aperture filter attenuate or shield the light components whose wavelengths correspond to the green andor blue.
13. A projector type image display apparatus comprising:
an illuminator including:
a light source to emit trichromatic light; and
a wavelength-selective optical aperture filter provided at the side of the light source from which the trichromatic light goes out and which consists of zones working as predetermined optical apertures, of which one selectively attenuates or shields a component of the trichromatic light, whose wavelength corresponds to at least one of the three primary colors, while the other zones allow the light components whose wavelengths correspond to the other primary colors to pass through; and
a color separation means for separating the trichromatic light output from the wavelength-selective optical aperture filter into components whose wavelengths correspond to the three primary colors, respectively;
three image display panels to modulate, according to a video signal, the light components separated by the color separation means and whose wavelengths correspond to the three primary colors, respectively;
a color synthesis means for combining together the light components modulated by the three image display panels and whose wavelengths correspond to the three primary colors, respectively, to produce synthetic light; and
a projection lens to project the synthetic light from the color synthesis means onto a screen.
14. The apparatus as set forth in claim 13, wherein the zones of the wavelength-selective optical aperture filter correspond to the component of the trichromatic light, having a wavelength corresponding to the red, green or blue of the three primary colors.
15. The apparatus as set forth in claim 13, further comprising a pair of fly-eye lenses formed from a plurality of lens element, being provided along the outgoing direction the trichromatic light from the light source, and which separates the trichromatic light emitted from the light source into primary-color light components and allows the separated primary-color light components to pass through the plurality of lens elements, thereby uniformizing the trichromatic light output.
the wavelength-selective optical aperture filter being provided adjacent to one of the pair of fly-eye lenses that is farther from the light source.
16. The apparatus as set forth in claim 15, wherein:
one of the main surfaces of the pair of fly-eye lenses that is farther from the light source is formed flat; and
the wavelength-selective optical aperture filter is formed on the flat surface of the fly-eye lens farther from the light source.
17. The apparatus as set forth in claim 15, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the lens elements of the pair of fly-eye lenses.
18. The apparatus as set forth in claim 13, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the light components whose wavelengths correspond to the three primary colors: red, green and blue, respectively.
19. The apparatus as set forth in claim 13, wherein:
the light source is a metal halide lamp or ultra-high voltage mercury lamp; and
the zones of the wavelength-selective optical aperture filter attenuate or shield the light components whose wavelengths correspond to the green andor blue.
20. The apparatus as set forth in claim 13, wherein the image display panels are liquid crystal panels.
21. A projector type image display apparatus comprising:
an illuminator including:
a light source to emit trichromatic light;
a pair of fly-eye lenses each formed from a plurality of lens elements and which separates the trichromatic light emitted from the light source into primary-color light components and allows the separated primary-color light components to pass through, thereby uniformizing the trichromatic light output; and
a wavelength-selective optical aperture filter provided adjacent to one of the fly-eye lenses that is farther from the light source and which consists of zones working as predetermined optical apertures, of which one selectively attenuates or shields a component of the trichromatic light, whose wavelength corresponds to at least one of the three primary colors, while the other zones allow the light components whose wavelengths correspond to the other primary colors to pass through the plurality of lens elements; and
means for splitting the trichromatic light output from the wavelength-selective optical aperture filter into components whose wavelengths correspond to the three primary colors, respectively;
three image display panels to modulate, according to a video signal, the light components separated by the color separation means from the illumination light and whose wavelengths correspond to the three primary colors, respectively;
a color synthesis means for combining together the light components modulated by the three image display panels and whose wavelengths correspond to the three primary colors, respectively, to produce synthetic light; and
a projection lens to project the synthetic light from the color synthesis means onto a screen.
22. The apparatus as set forth in claim 21, wherein the wavelength-selective optical aperture filter has the zones formed at random correspondingly to the lens elements of the fly-eye lenses.
23. The apparatus as set forth in claim 21, wherein:
one of the main surfaces of the pair of fly-eye lenses that is farther from the light source is formed flat; and
the wavelength-selective optical aperture filter is formed on the flat surface of the fly-eye lens farther from the light source.
24. The apparatus as set forth in claim 21, wherein the wavelength-selective optical aperture filter has the zones formed correspondingly to the light components whose wavelengths correspond to the three primary colors: red, green and blue, respectively.
25. The apparatus as set forth in claim 22, wherein:
the light source is a metal halide lamp or ultra-high voltage mercury lamp; and
the zones of the wavelength-selective optical aperture filter attenuate or shield the light components whose wavelengths correspond to the green andor blue.