EP0568998A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Image forming apparatus and projector using the same
Assignee: Canon Inc
•
Filing: 1993-05-05
•
Granted: —
•
Expires: 2013-05-05
Abstract
Abstract An image forming apparatus of this invention relates to an image forming apparatus for forming a color image and, more particularly, to a projector using the image forming apparatus. The image forming apparatus includes a color light illuminating system having first and second light sources for emitting different color light components, and first, second, and third imaging units or liquid crystal light valves for modulating the color light components to form color images. The first light source is a light source for mainly emitting two color components corresponding to the images formed by the first and second imaging units, and the second light source is a color light source for mainly emitting a color component corresponding to the image formed by the third imaging unit. <IMAGE>
Inventors
- 👤 Katsumi C/O Canon Kabushiki Kaisha Kurematsu
- 👤 Tsunefumi C/O Canon Kabushiki Kaisha Tanaka
- 👤 Takeshi c/o Canon Kabushiki Kaisha Abe
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 16:47
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; G; G03; G03B; G03B21/00; G03B21/14; G03B21/20; G03B21/2006; G03B21/2013; G03B21/2073; H04N9/3141; H04N9/315
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
92 words
An image forming apparatus comprising: color light illuminating means having first and second light sources for emitting mutually different color light components; and first, second, and third imaging means for modulating the color light components to form color images, wherein said first light source is a light source for mainly emitting two color components corresponding to the images formed by said first and second imaging means, and said second light source is a color light source for mainly emitting a color component corresponding to the image formed by said third imaging means.
Claim 2
Dependent Claim
47 words
An apparatus according to claim 1, wherein said color light illuminating means comprises color separating means, arranged in an optical path from said first light source, for separating light into two color light components corresponding to the color images formed by said first and second imaging means.
Claim 3
Dependent Claim
46 words
An apparatus according to claim 2, wherein said first light source is a color light source for emitting color light mainly containing green and red components, and said second light source is a color light source for emitting color light mainly containing a blue light component.
Claim 4
Dependent Claim
45 words
An apparatus according to claim 2, wherein said first light source is a color light source for emitting color light mainly containing blue and red components, and said second light source is a color light source for emitting color light mainly containing a green component.
Claim 5
Dependent Claim
37 words
An apparatus according to claim 3, wherein said color synthesizing means comprises a plurality of dichroic mirrors, and said plurality of dichroic mirrors and said color separating means have functions of reflecting the green light components, respectively.
Claim 6
Dependent Claim
87 words
An image forming apparatus comprising: first, second, and third imaging means for forming images corresponding to red, green, blue, respectively; color synthesizing means for synthesizing image light components from said first, second, and third imaging means; and first, second, and third light sources for illuminating said first, second, and third imaging means, respectively, wherein said first, second, and third light sources are color light sources for emitting color light mainly containing color components of the color images formed by said first, second, and third imaging means, respectively.
Claim 7
Dependent Claim
25 words
An apparatus according to claim 6, further comprising light amount adjusting means arranged in optical paths from said first, second, and third light sources, respectively.
Claim 8
Dependent Claim
115 words
A projector comprising: a reflector having a substantially elliptical shape; a light source arranged near one focal point of said reflector; information forming means for modulating light from said light source to form information; and a projection lens for projecting information light formed by said information forming means, said projection lens being arranged such that a pupil of said projection lens is located near the other focal point of said reflector, wherein said information forming means is located at a position substantially equidistantly from the two focal points, so that non-image light reflected by said information forming means of the light emitted from said light source is directed toward a portion near said light source.
Claim 9
Dependent Claim
63 words
A projector according to claim 8, further comprising an interference-type mosaic filter, at a light source side of said information forming means, for transmitting a predetermined color component and reflecting remaining color components so as to focus the light from said light source in a mosaic pattern of red, green, an blue, thereby directing the reflected remaining color component near said light source.
Claim 10
Dependent Claim
60 words
A projector according to claim 8, wherein said information forming means comprises a liquid crystal light valve, a reflecting surface is formed in a portion between pixels and a portion except for a display area of said light valve, on a light source side of said light valve, thereby directing light reflected by said reflecting surface near said light source.
Claim 11
Dependent Claim
96 words
A projector according to claim 8, further comprising polarizing converting means, formed between said light source and said information forming means, for splitting the light from said light source into a pair of polarized light components having mutually different polarization states, directing one polarized light component toward said information forming means, and returning the other polarized light component near said light source, so that at least part of said other polarized light component is converted to have a polarization state coinciding with that of said one polarized light component through said light source and said reflector.
Claim 12
Dependent Claim
15 words
A projector according to claim 11, wherein said polarizing converting means includes a grid polarizer.
Claim 13
Dependent Claim
65 words
A projector according to claim 11, wherein said polarizing converting means comprises a polarizing beam splitter and a reflecting member for reflecting said other polarized light component, and said reflecting member returns said other polarized light component near said light source through said polarizing beam splitter and is located at a position equivalent to a position substantially equidistantly spaced apart from the two focal points.
Claim 14
Dependent Claim
99 words
An information forming apparatus comprising: a reflector of a shape having at least one focal point; a light source located near the focal point; information forming means for modulating light from said light source to form information light; and a mosaic color filter for making the light incident on said information forming means into a mosaic shape of red, green, and blue, wherein said mosaic color filter is an interference-type filter for transmitting any color component of red, green, and blue and reflecting remaining color components, so that the reflected remaining color components are directed near said light source.
Claim 15
Dependent Claim
100 words
A color information forming apparatus comprising: color light illuminating means having first and second light sources for emitting different color light components; and first, second, and third information forming means for modulating the color light components to form color images, wherein said first light source is a color light source for mainly emitting two color components corresponding to the information light components formed by said first and second information forming means, and said second light source is a color light source for mainly emitting a color component corresponding to the information light component formed by said third information forming means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.