Electrophotography – Machine operation – Job mode
Reissue Patent
2000-08-04
2002-08-06
Chen, Sophia S. (Department: 2852)
Electrophotography
Machine operation
Job mode
C399S196000
Reissue Patent
active
RE037812
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to setting of an optional magnification of image formation in an image forming process which is performed by an image forming apparatus.
2. Description of the Related Art
In an image forming apparatus, especially in a copying machine, a laser printer and the like which utilize electrophotographic method, a photosensitive material which is a recording medium is uniformly electrified so that after uniform electrification, reflected light from an original or laser light which is driven in accordance with image information irradiates and forms an electrostatic image corresponding to the image on a surface of the photosensitive material, and a developing agent is used to develop the electrostatic image and obtain a visible image. The developed image is transferred onto a sheet of paper which is transported appropriately and the sheet of paper is fed into a fixing apparatus so that a toner image transferred onto the sheet of paper is fixed as a permanent image and thereafter outputted outside.
After electrifying the photosensitive material to a predetermined polarity, an image is exposed on the surface of the photosensitive material at an optional magnification which is preliminarily set. That is, where the magnification is equivalent, the image as it is exposed, i.e., exposure is performed under a condition of 1:1, whereas for image reduction, an optical image having the size less than 1 against the image having the size 1 is exposed and focused.
For example, in a copying machine, a reflected optical image from an original is focused, as it is reduced or enlarged, on a photosensitive material through an imaging lens or the like. Meanwhile, in a digital image forming apparatus such as a laser printer, the size of a laser beam is not controlled in accordance with a ratio of enlargement. Rather, the number of pixels of an image is controlled. For instance, the number of pixels is reduced in accordance with the magnification of reduction of the image, and the number of pixels is increased for enlargement of the image.
Conventionally, in the case where the size of an original and the size of a paper to be used are fixed sizes, it is possible to form an image in accordance with a preset magnification. For example, where the original sizes are A3, A4, B4 and B5 of the Japanese Industrial Standards and the paper sizes are A4, A5, B4 and B5, the image is exposed on a surface of a photosensitive material at a magnification of 1.22× (122%) when the original size is A4 and the paper size of a paper on which an image is to be formed is B4, and the image is exposed on the surface of the photosensitive material at a magnification of 0.86× (86%) when the paper size is B5.
In the case where the original size is B4 and the paper size of a paper to be used is A4 or B5, the image is exposed at a magnification of 0.81× (81%) or 0.70× (70%). In the case where the original size is B5 and the paper size of a paper to be used is A4 or B4, the image is exposed at a magnification of 1.15× (115%) or 1.41× (141%).
As described above, when an original of a fixed size and a paper of a fixed size are used, image exposure is performed at a predetermined magnification so that all images contained in the original are formed on the paper. Such a predetermined magnification is called a fixed magnification. To prefer an image at a fixed magnification, a setting key for selecting only the fixed magnification (i.e., a fixed magnification key) is provided. With respect to a fixed magnification key, there are several cases such as a case where fixed magnification keys as many as magnifications described above are provided, a case where with only one setting key, one can set a fixed magnification cyclically in an order of 70%→81%→86%→(100%; sometimes omitted)→115%→122%→141%→70%, a case where one setting key is provided to set a fixed magnification in a direction for enlargement (70%→81% . . . 141%) and another setting key is provided to set a fixed magnification in a direction for reduction (141%→122% . . . 70%).
Separately from this, a zoom key or the like is provided with which it is possible to change a magnification by 1%. In short, this key is used to set an optional magnification which is preferred by a user, not to set fixed magnifications described above. For instance, when the original size is A4 and the paper size of a paper on which an image is to be formed is B5, while there is no problem for forming an image at a fixed magnification of 86%, the zoom key is used to form an image at a little smaller magnification (e.g., 83%).
In a conventional magnification setting apparatus described above, there are a key for setting a fixed magnification and a zoom key for freely setting an optional magnification. Therefore, by manipulating these keys, an image can be formed at a desired magnification.
However, during setting of a magnification described above, although a skilled operator is capable of easily manipulating, an unskilled operator can not very often understand at all what a fixed magnification is. That is, even though an unskilled operator can understand that the original size is B4, he can not understand at all whether to set a magnification by manipulating a fixed magnification key or by manipulating a zoom key for the purpose of form an image on an A4 paper. In addition, where a fixed magnification is to be set by means of a zoom key, an unskilled operator does not know the fixed magnification to be set, often ending up in setting a wrong magnification. To avoid this, an unskilled operator must to refer to a comparison chart while setting a magnification, which is very bothersome.
Further, provision of a fixed magnification key and a zoom key separately from each other as described above simply increases the number of setting keys to be used by an operator so that it is very hard for the operator to understand which key to manipulate to easily set a desired magnification, which forces the operator a bothersome operation. In addition, since the operator must set a magnification while looking at the comparison chart described above, without the comparison chart, the operator may rely on his own intuition when setting a wrong magnification and end up in making an undesired copy.
Except for a fixed magnification key and a zoom key, as described in Japanese Patent Application Laid-Open Gazette No. 4-3547, often-used magnifications may be stored in advance and setting keys for setting such magnifications may be provided separately from zoom key and the fixed magnification key. Where such setting keys are provided, the magnifications which are very often used can be set by an easy manipulation. However, a user must store such magnifications in advance, and therefore, an inexperienced user feels awkward toward the increased number of the setting keys and finds setting of a magnification very pressurizing.
To deal with this, for the purpose of setting fixed magnifications, setting keys may be provided for the respective fixed magnifications as described in Japanese Patent Application Laid-Open Gazette No. 4-3547, and printing may be realized on fixed sizes which correspond to the respective setting keys. For instance, for a fixed magnification key choosing 70%, an optimal paper size is displayed which is optimum for forming an image which corresponds to the original size, such as B4→B5, A3→A4.
However, in the case where there are a number of keys, such as keys corresponding to respective fixed magnification keys, a zoom key, and a special fixed magnification key as described above, provided for providing such a display described above, due to a restriction to a space on an operation panel for providing a number of keys, printing or displaying with very small letters can not avoided in reality. Such a display is very hard to look at, making reference to the display very rare. Further, when combinations of optimal conditions for all originals and a
Ishikura Kaoru
Okamoto Yuji
Chen Sophia S.
Sharp Kabushiki Kaisha
LandOfFree
Magnification setting apparatus for image forming apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnification setting apparatus for image forming apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnification setting apparatus for image forming apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2920228