Incremental printing of symbolic information – Electric marking apparatus or processes – Electrostatic
Reexamination Certificate
1998-11-06
2001-05-22
Lee, Susan S. Y. (Department: 2852)
Incremental printing of symbolic information
Electric marking apparatus or processes
Electrostatic
C347S130000, C347S232000
Reexamination Certificate
active
06236416
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image forming apparatus such as an electrophotographic copying apparatus, and more particularly to an image forming apparatus having a linear array of a plurality of photosensitive members and utilizing such photosensitive members in an independent manner, thereby forming cyan, magenta, yellow and black images respectively corresponding to the photosensitive members and synthesizing these images to form a color image.
2. Related Background Art
There is already known a laser beam image forming apparatus, in which laser light sources are provided as image exposure means respectively corresponding to four electrophotographic photosensitive members arranged in a linear array and are controlled respectively corresponding to the image information of cyan, magenta, yellow and black colors to form electrostatic latent images respectively corresponding to the cyan, magenta, yellow and black colors on the four electrophotographic photosensitive members, then such electrostatic latent images are respectively developed and the developed images are synthesized to obtain a color image.
Also there is known an LED light image forming apparatus in which four LED's are provided respectively corresponding to the photosensitive members, as the light sources for forming the electrostatic latent images of cyan, magenta, yellow and black colors, in place for the laser beam sources in the above-mentioned image forming apparatus.
In the aforementioned laser beam image forming apparatus, in order to synthesize the images of cyan, magenta, yellow and black colors in mutually registered manner, it is required to exactly match the scanning operations of the four laser light sources, provided respectively on the four photosensitive members, securely in the main and subscanning directions, but in practice it is difficult to exactly match the four laser lights in the main and subscanning directions.
On the other hand, in the above-mentioned LED light image forming apparatus, it is relatively easy to meet the above-described requirements of matching in the main and subscanning directions, but such apparatus is even more expensive since a plurality of expensive LED chips have to be jointed in a linear array to obtain a jointed LED element. Besides, since the LED chips fluctuate in the light emission characteristics, the image reproducibility is deteriorated in the main scanning exposure direction, relative to the movement of the photosensitive member, to be exposed by the above-described jointed LED element, because the exposure condition differs for each LED chip.
Also in the electrophotographic copying apparatus capable of forming a color image, the above-described jointed LED element has to be provided for each of the plurality of photosensitive members, and the light emission characteristics become different among the plurality of jointed LED elements corresponding to the plurality of photosensitive members. Consequently, there emerges a difficult requirement of matching the light emission characteristics among such jointed LED elements.
SUMMARY OF THE INVENTION
An object of the present invention is to resolve the fluctuation in the light emission characteristics in the main scanning direction, encountered in the image forming apparatus, particularly electrophotographic copying apparatus, employing a jointed LED element as the exposure device.
Another object of the present invention is to resolve the fluctuation in the light emission characteristics among the plurality of jointed LED elements, encountered in the color image forming apparatus employing a plurality of photosensitive members and exposure devices consisting of a plurality of jointed LED elements provided respectively corresponding to the photosensitive members.
The above objects can be achieved by the present invention described below.
According to the present invention there is provided an image forming apparatus comprising: a photosensitive member; an exposure means including a single-chip light emission element array formed by integrating a plurality of light emitting elements in a single chip which exposure means executes the exposure in the main scanning direction relative to the movement of the photosensitive member, by the light emission from said single-chip light emission element array; and a developing means provided around said photosensitive member.
According to the present invention there is also provided an image forming apparatus comprising: a plurality of photosensitive members provided mutually independently; an exposure means including a plurality of single-chip light emission element arrays obtained by forming, on a single substrate, a plurality of light emission element arrays each consisting of a plurality of light emitting elements and separating each of said plurality of light emission element arrays, and constructed by positioning said plurality of single-chip light emission element arrays respectively corresponding to said plurality of photosensitive members; and a plurality of developing means provided respectively around said plurality of photosensitive members.
REFERENCES:
patent: 4356429 (1982-10-01), Tang
patent: 4435064 (1984-03-01), Tsukada et al.
patent: 4539507 (1985-09-01), VanSlyke et al.
patent: 4720432 (1988-01-01), VanSlyke et al.
patent: 4721977 (1988-01-01), Fukae
patent: 4769292 (1988-09-01), Tang et al.
patent: 4885211 (1989-12-01), Tang et al.
patent: 4888603 (1989-12-01), Hart et al.
patent: 4906544 (1990-03-01), Osawa et al.
patent: 4950950 (1990-08-01), Perry et al.
patent: 5047687 (1991-09-01), VanSlyke et al.
patent: 5059861 (1991-10-01), Littman et al.
patent: 5059862 (1991-10-01), VanSlyke et al.
patent: 5061617 (1991-10-01), Maskasky
patent: 5073446 (1991-12-01), Scozzafava et al.
patent: 5151629 (1992-09-01), VanSlyke
patent: 5294869 (1994-03-01), Tang et al.
patent: 5294870 (1994-03-01), Tang et al.
patent: 5339150 (1994-08-01), Hubble, III et al.
patent: 5497225 (1996-03-01), Matsuzuki
patent: 5610685 (1997-03-01), Aiba
patent: 5740493 (1998-04-01), Otaki et al.
patent: 5793405 (1998-08-01), Shakuda
patent: 5874984 (1999-02-01), Scholz et al.
patent: 6002420 (1999-12-01), Tanioka et al.
patent: 6052136 (2000-04-01), Tanioka et al.
patent: 6121994 (2000-09-01), Kuribayashi et al.
patent: 44 34 081 (1995-05-01), None
patent: 195 14 073 (1995-11-01), None
patent: 0 335 553 (1989-10-01), None
patent: 0 349 265 A2 (1990-01-01), None
patent: 0 464 948 (1992-01-01), None
patent: 0 547 854 (1993-06-01), None
patent: 0 618 078 (1994-10-01), None
patent: 0 704 915 (1996-04-01), None
patent: 8-48052 (1996-02-01), None
Hashimoto Yuichi
Kuribayashi Masaki
Mashimo Seiji
Senoo Akihiro
Tsuzuki Hidetoshi
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Lee Susan S. Y.
LandOfFree
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