AREA SETTING DEVICE

Abstract: An area setting device for setting coordinates of two points in diagonal direction of one or more number of areas by sequential key operations. Different colors are used for coordinates display (53, 53x, 53y) by each direction, the same colors as coordinates display are used for coordinates input indicator (52). Memorizing means (62, 63) memorize all the points as coordinates input condition or coordinates non-­ input condition, whereby the key input is accepted to the point of the highest order of all the points of coordinates non-input condition, and converted into memorized condition as the point of coordinates input condition. Then key input accept­ ance and memory state conversion are repeated for coor­ dinates input of the points required.

Description: BACKGROUND OF THE INVENTION The present invention relates to an area setting device, more particularly an area setting device which can set the areas required for special processing such as the operation to form images only within the preset range of the obtained image signals (briefly called trimming in the following text) or the operation to form no images only within the preset range (briefly called masking in the following text) by setting the coordinates of two points in diagonal direction of area. To image forming apparatus used for copying machines and others, multi-function arrangement has been demanded more and more, and image forming apparatus having edit function such as trimming and masking as a part of multifunction arrangement have been offered. Such image forming apparatus having edit function are provided with an area setting device because area setting is essential for edit processing. To be more specific, the device used is of the type so composed to enable setting of desired areas by setting documents under a cover having a grid pattern and an indicator to show values of coordinates perpendicular to each other, by selecting the mode such as trimming and masking, then by inputting the numeric values corresponding to the setting range related to the X-axis under the condition of operation of the coordinates designation key and X-key, then by inputting the numeric values corresponding to the setting range related to the Y-axis by ten key under the condition of operation of the Y-key. (Refer to the Official Gazzette of Japanese Patent Publication (unexamined) No. 43480/1983.) With the area setting device having the composition as described above, desired areas can be set or the area once set can be changed by sequential operation of the required keys. However, the key operation is intricated and very difficult for inexperienced operators, and erroneous setting or alteration of coordinates becomes more probable. To change the coordinates of a point of which input has already been completed, first the coordinate change key is operated, then input for setting new coordinates is made by operating the X-key, Y-key, and ten-keys. If the operator is inexperienced, however, it can happen that coordinates which need no alteration are changed and unexpected images are formed. As is evident from the above description, setting of any desired area can be made by operating the necessary keys in sequence. The trouble is that operation is very difficult for inexperienced operators and setting of coordinates for wrong axis by mistake becomes more likely as the key operation is complicated and directions of X-axis and Y-axis are not obvious. SUMMARY OF THE INVENTION An object of the present invention is to provide an area setting device of easier use by simplified arrangement for area setting operation which can set and change coordinates easily by same key operation, which enables accurate area setting even by inexperienced operators and further allows easy and exact recognition of the direction of the coordinates to be set. The above object is solved by an area setting device comprising a coordinate setting keyboard for setting coordinates of two corresponding diagonal corner points of one or more rectangular areas within a copying zone of a copying apparatus, said keyboard including coordinate setting keys and a display for indicating said coordinates, which is according to the invention characterized by memory means arranged in a predetermined order corresponding to the sequence of the corner points of the rectangular areas for memorizing set states and enabling states of coordinate setting operations corresponding to each corner point which can be set, a coordinate input key for enabling the memory means to memorize the set state for coordinates which have been input by the coordinate setting keys, first memory control means for controlling the memory means to memorize the enabling state for a first corner point when coordinate input operations have been completed for all desired areas, coordinate input control means for accepting only a coordinate setting key input indicative of the first point among the points for which enabling states have been memorized, judging means for determining whether the next point following said first point in the predetermined order is memorized in the set state or in the enabling state, second memory control means responsive to the determination made by the judging means, and to a determination that a coordinate has been input for said first point or no more coordinates are to be input for said first point, for controlling the memory means to memorize the set state for said first point and the enabling state for said next point. According to an advantageous development the area setting device further comprises a transparent member to be positioned on a document placed on the copying zone, an area of which is to be set, said member containing coordinate displays in directions crossing each other at right angles marked at specific positions on the transparent member. According to a further advantageous development the area setting device further comprises an operation panel for inputting image forming conditions and having coordinate input position indicators corresponding to said directions and having coordinate value indicators corresponding to said directions at specific positions on the operation panel. According to a further advantageous development the coordinate displays on the transparent member are provided in different colors for each direction and the corresponding position indicators are provided in the same color for each direction. Preferably the coordinate value indicator shows coordinate values in the same color as the corresponding coordinate display. Fig. 1 is a block diagram showing an embodiment of the area setting device. Fig. 2 shows the operation panel for area setting operations. Fig. 3 shows an embodiment of the arrangement of the memory means 63 of Fig 1 and its function for the memorizing operation. Fig. 4 is a perspective view of the document holding section. Fig. 5 is an appearance perspective view of a copying machine. Fig. 6 is a diagramatic view showing internal mechanism of a copying machine. Fig. 7 shows another embodiment of the operation panel. Fig. 8 is a flow chart to explain area setting operation by the operation panel of Fig. 7. Fig. 9 is a block diagram showing the apparatus for judging effectiveness of set area. Fig. 10 is a flow chart to explain effectiveness judging operation. Fig. 11 shows a specific example of set area. Fig. 12 is a block diagram to show the device for forming images in the range corresponding to set area. Fig. 13 is a partially cut off view in perspective of a blank lamp. Fig. 14 is a vertical sectional view of the blank lamp, and Fig. 15 is a flowchart to show the key points of image forming operation. DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is further described while referring now to the attached drawings showing a preferred embodiment. Fig. 5 is an appearance perspective view of a copy machine as a kind of image forming apparatus. A document tray (11) is attached to the upper face of the copying machine proper (1) allowing to move back and forth freely, and an operation panel (12) for setting ordinary copy data is also attached. Another operation panel (5) for setting edit data is attached to the front bottom, and a paper feeding cassette (13) is attached to the bottom of a side in a manner that can be pulled out, and a receiving plate (14) to receive copying paper with formed images is attached to the bottom of the other side. Fig. 6 is a diagramatic view showing internal mechanism of the copying machine having an optical system (2), a copying section (3) and a paper conveying section (4) within the copying machine proper (1). The optical system (2) is composed of a lamp (21) to expose the document fixed on the document tray (11) by a document holder (15) and of a lens (22) to lead the reflected light from the document to the copying section (3). The copying section (3) comprises a corona discharger (32), blank lamp (33), developing device (34), transfer charger (35), separating charger (36), and a cleaner (37) arranged in the order mentioned and around a photoreceptor drum (31) which turns in one direction. On the surface of the photoreceptor drum (31) uniformly charged by the corona discharger (32), document image is led to the surface of the photoreceptor drum (31) so as to form the electro-static latent image, which is turned into apparent toner image by the developing device (34). The toner image is transferred by the transfer charger (35) onto the copying paper carried by the paper conveying section (4), and the copying paper is peeled off the photoreceptor drum (31) by the separating charger (36). The paper conveying section (4) is composed of a feed roller (41), resist roller (42), conveying belt (43), fixing apparatus (44), and a discharge roller (45). Copying paper is delivered sheet by sheet from the paper feeding cassette (13) by the feed roller (41), then is conveyed to the copying section (3) synchronized with the top end of the electro-static latent image by the resist roller (42). The copying paper peeled off the photoreceptor drum (31) by the separating charger (36) is carried to the fixing apparatus (44) by the conveying belt (43) and the copying paper onto which the toner image is fixed in the fixing apparatus (44) is discharged onto the receiving plate (14) by the discharge roller (45). Fig. 2 shows the operation panel (5) having an edit operating condition select key (50), coordinate data call key (51), coordinate input position display (52), coordinate value display (53), edit mode (trimming, masking etc.) select key (54), ten-key keyboard (55), clear key (56), and a coordinate input key (57). To be more specific, the coordinate input condition display (52) selectively indicates input in X-direction, X1-1, X1-2, X2-1, X2-2, and input in Y-direction, Y1-1, Y1-2, Y2-1 and Y2-2 corresponding to two points in diagonal direction of two areas. The coordinate value display (53) has an indicator (53X) for coordinate values in X-direction and an indicator (53Y) for coordinate values in Y-direction. Fig. 4 is a perspective view of the document holder (7) which is composed of a holding member (71) to hold a document and a transparent member (72) to cover the document connected together at one side so as to be opened and closed. To be more specific, the holding member (71) is made of synthetic resin sheet and set position mark (73) according to each document size is marked at the specific position on the sheet. The transparent member (72) is made of transparent synthetic resin and comprises coordinate value display marks (74) in the directions crossing at right angles each other and a lattice (75) for easier reading of coordinates values. Fig.1 is a block diagram showing the circuitry of an embodiment of the area setting device. The signals from the above mentioned ten keys (55) and the signals from the coordinate input key (57) are applied through the coordinate input controller (62) to the memory (61) which memorizes the coordinates of each point, and the signals from the coordinate input key (57) are applied to the memory means (63) which memorizes conditions of each point separating into coordinate input conditions (set states), and coordinates non-input conditions (enabling states). Information from the memory means (63) showing condition of each point is given to the judging section (65) under the control of the read control section (64) which is provided with the signal from the coordinate data call key (51). And the signals from the coordinate input key (57) are given to the judging section (65). The signals from the judging section (65) are applied to the 1st memory control section (66), the judged signals from the judging section (65) and also the signals from the coordinate input key (57) are applied to the 2nd memory control section (67), and the control signals from the 1st memory control section (66) and from the 2nd memory control section (67) are applied to the memory means (63). The read signals from the read control section (68) to read the coordinate values memorized in the memory means (61) are applied to the coordinate value display (53) in response to the signals from the read control section (64) corresponding to the signals from the coordinate data call key (51). The read signals from the read control section (64) corresponding to the signals from the coordinate data call key (51) are also applied to the coordinate input position display (52). By the area setting device of the above composition, selection of modes such as trimming and masking is possible in the initial stage of area setting operation by operating at first the edit operating condition select key (50) and then by operating the edit mode select key (54). A document is set between the holding member (71) and the transparent member (72) fitting the set position mark (73), then the coordinate values of the area to be set are read from the coordinate display marks (74) and the lattice (75) of the transparent member (72). After operating the ten-keys of the keyboard (55)so that the coordinate value indicator (53) shows the desired value under the above condition, one coordinate value (e.g. X-value) of the 1st corner point can be set by operating the coordinate input key (57). (In this example, input in X direction, X1-1 for example, is displayed.) Then the other coordinate value (e.g. Y-value) of the first corner point can be set by operating the ten-keys (55) and the coordinate input key (57). (In this example, input in Y direction, Y1-1 for example, is displayed.) At this time, the part of the memory means (63) corresponding to this specific corner point is changed into coordinate input condition (set state) by the signals from the coordinate input key (57). By repeating the above operations, it is possible now to set the coordinates of the corresponding corner points in diagonal direction of all desired areas. When the coordinate setting operation for all the corner points is completed, the part of the memory means (63) corresponding to the 1st corner point is changed to coordinate non-input condition (enabling state). Even after the completion of the coordinate setting operation for all the required points, the respective set values can be changed. First the coordinate data call key (51) is operated, then the coordinate values of the corner point having the highest order among the corner points which are in the memory means (63) in the coordinate non-input condition read out from the memory means (61) to be displayed on the coordinate value display (53), and the coordinate input position display (52) corresponding to one coordinate of the specific point is turned on. Thereupon, it is possible to memorize new coordinate values in the memory means (61) in place of the original coordinate values by operating the ten-keys (55) and the coordinate input key (57). To the point that requires no alteration of the coordinate values, only the coordinate input key (57) is operated, then the point having the next lower order is displayed as the point which can be changed. Fig. 3 shows an embodiment of the memory means (63) composed of memories of 8-bits in which coordinate input condition (set state) is shown by "1" and coordinate non-input condition (enabling state) is indicated by "0". From right to left the order is increased wherein each bit corresponds to X-coordinate, Y-coordinate of the 1st point in the 1st area, ..., X-coordinate, Y-coordinate of the 2nd point in the 2nd area, in due order. It is to be noted that in Fig. 3 the coordinates of the point for which the corresponding lower bit (e.g. corresponding to the X-coordinate) shows "0" status is in the condition for coordinate setting (enabling state). To indicate the corner point which is ready for coordinate input, therefore, the coordinate input position display (52) displays a point for which the corresponding lower bit, e.g. the bit corresponding to the X-coordinate has "0" state in the memory means (63) with flashed indication and displays a point for which the corresponding lower bit has "1" state with a continuously ON indication. The coordinate values of the point flashing are displayed on the coordinate value display (53). For coordinate input, the content of the memory means (63) is judged whether or not the next bit following the "0" bit for which the coordinate is to be set is in "0" state. If the bit is in "0" state, this state is kept even after setting the preceding bit to "1" indicating the completed coordinate input operation. If this following bit is in "1" state, it is changed to "0" state after completing the coordinate input operation. Also in this case, the input coordinate values are written into the memory means (61). In Fig. 3, A - E show bit condition of the memory means (63) upon sequential input of coordinate values and the bits are changed to "1" state from the lowest order one after another at every setting operation. Thereby it has been assumed as an example, that all cells of the memory means (63) initially are containing "0". To allow the change of coordinate values of a required corner point after input of its values, its bit of the lowest order, e.g. indicating the X-coordinate, is inverted from "1" to "0" state by operating the coordinate data call key (51). Thus the setting of a new coordinate value is possible by operating required keys. When setting of a new coordinate value is made, the lower bit (e.g. the bit corresponding to the X-coordinate) is changed to "1" state, and the nex bit is turned to "0" state to be ready for input of the coordinate value corresponding to this bit. By the above embodiment, therefore, it is possible to input the present coordinates in sequence without any special operation of the preset coordinate values by memorizing for each point selectively the condition of input coordinate or the condition of non-input coordinate. Moreover, a coordinate value can be changed easily only by input of a new value when the present coordinate value is called. Accordingly, operation of area setting can be made simple. Another advantage is that the trouble of setting document again on the document tray (11) can be omitted by setting a copy obtained by one copying operation on the document holder, and by setting the coordinates and that the coordinate setting can be exact. As a more preferred embodiment, the coordinate input position display (52) is so made to indicate X-direction inputs X1-1, X1-2, X2-1, X2-2 and Y-direction inputs Y1-1, Y1-2, Y2-1, Y-2-2 corresponding to two points in diagonal direction selectively for two areas, and these are displayed in the same color to each one of X-direction coordinate value indication and Y-direction coordinate value indication of the document holder (7) to hold document for area setting. The coordinate value display (53) has X-direction coordinate value indicator (53X) and Y-direction coordinate value indicator (53Y), and each coordinate value is shown in the same color as the above state X-direction coordinate value indication and Y-direction coordinate value indication respectively. The above mentioned lattice (75) is in the same color as each one of the corresponding coordinate value indication (74). To be more specific, the coordinate value indication (74) and the lattice (75) are colored in red at the parts parallel to the connected one side (called Y-direction parts in the following text) (74Y) and in green at the parts perpendicular to the side (called X-direction parts) (74X). Corresponding to the above coordinate indication (74) and the lattice (75), the coordinate input position display (52), therefore, is colored in red and green and the coordinate value display (53) also displays coordinate values in red and green corresponding to the coordinate indication (74) and the lattice (75). In other words, Y-coordinate value display (53Y) is in green and X-coordinate value display (53X) is in red. By the above preferred embodiment, it is displayed which coordinate value of the point of n-th order should be set by selectively driving the displays for X-direction input position X1-1 and Y-direction input position Y1-1, and the value is displayed in the same color (red or green) as the corresponding coordinate value indication (74) and lattice (75). The trouble of setting coordinate value of wrong direction by mistake can therefore be prevented effectively. It is also possible to make sure that the displayed data are those of the desired direction easily and exactly at coordinate setting, at the end of coordinate setting, or at checking of already set coordinates by operating the coordinate data call key (51) because the displayed data on the coordinate value display (53) are in the same color as the corresponding coordinate value display (74) and the lattice (75) (red or green). By the above embodiment, each direction of each point to be set is displayed corresponding to the color of the coordinate indication in each direction of the transparent member set on the document. Accordingly, coordinates are set in correct setting direction by visually reading the coordinate in the direction to be set and of the point to be set on the same colored part of the coordinate indication of the transparent member, which serves for exact setting of area. Fig. 7 shows another embodiment of the operation panel, which comprises a print key (76), two keys (77), density setting scale (78), color designating key (79), coordinate value display (81), mode select key (82) for selecting modes such as trimming and masking, mode indicator (83) to indicate selected mode, coordinate input key (84), input end key (85), coordinate value adjust key in width direction (86) as a coordinate designation key in transversal direction, coordinate value adjust key in length direction (87) as a coordinate designation key in longitudinal direction, input condition indicator in width direction (88), input condition indicator in length direction (89), square area indicator (80), and coordinate input position indicators (80a) (80b) corresponding to two points in diagonal direction of the area indicator (80). By operating the mode select key (82), therefore, it is possible to show the selected mode on the mode indicator (83). To set coordinate values in transversal direction, operate the coordinate input key (84) then the transversal coordinate value adjust key (86), and the desired coordinate value in transversal direction can be selected. Moreover, it is possible to judge easily which key should be operated corresponding to increase or decrease of coordinate values because each coordinate adjust key is composed of a key in coordinate value increase direction and a key in coordinate value decreasing direction, and the coordinate value decreasing key is provided at the side of the origin. Execution of setting operation of the coordinate values in transversal direction can be indicated in this case by turning the transversal direction input condition indicator (88) to ON. When a desired coordinate value in transversal direction is selected, input of the coordinate value can be made by operating the coordinate input key (84). To set coordinate values in longitudinal direction, on the other hand, operate the coordinate input key (84) (there is no need to operate the key again if it is operated for preceding coordinate value setting), then operate the longitudinal coordinate value adjust key (87), and the desired coordinate value in longitudinal direction can be selected. In this case, it can be indicated that setting operation of coordinate values in longitudinal direction is currently carried out by turning on the longitudinal input condition indicator (89). When a desired coordinate value in longitudinal direction is selected, input of the coordinate value can be made by operating the coordinate input key (84). The point which should be set is indicated by turning on the coordinate input position indicators (80a) (80b) one after another at every setting of coordinate value by operating the coordinate input key (84). Fig. 8 is a flow chart for detailed description of area setting operation. At step (1), it is judged whether or not the input end key (85) is operated, and if operated, the area setting operation completes. If not operated, it is judged at step (2) whether or not the coordinate input key (84) is operated. If the judgement at step (2) is for no operation of the coordinate input key (84), it is judged at step (5) and (6) whether or not the transversal direction coordinate value adjust key (86) and longitudinal direction coordinate value adjust key (87) are operated. If only the transversal coordinate value adjust key (86) is operated, indication of the coordinate value display (81) corresponding to the transversal coordinate value adjust key (86) operated is adjusted at step (7), then judgement of the step (1) and so on is carried out. If not, judgement and processing of the step (1) and so on are carried out as it is. When the judgement at step (2) is for operation of the coordinate input key (84), on the other hand, it is judged at step (3) and (4) whether or not the input end key (85) and the coordinate input key (84) are operated in the same manner as at step (1) and (2) after input of coordinate values. If neither key is operated, it is judged at step (8) and (9) whether or not the transversal coordinate value adjust key (86) and longitudinal coordinate value adjust key (87) are operated. If only the longitudinal coordinate value adjust key (87) is operated, indication of the coordinate value display (81) corresponding to the longitudinal coordinate value adjust key (87) operated is adjusted at step (10), then judgement at step (3) and so on follows. If not, judgement and processing at step (3) and (4) follow as it is. If the judgement at step (3) is for operation of the input end key (85), the area setting operation completes. If the judgement at step (4) is for operation of the coordinate input key (84), judgement and processing at step (1) and so on are carried out after input of coordinate values. In short, input by the transversal coordinate adjust key (86) or longitudinal coordinate adjust key (87) is selectively accepted at every operation of the coordinate input key (84). This can prevent exactly such a trouble, for example, that the coordinate values in longitudinal direction are changed in the middle of setting or coordinate values in transversal direction. By the above embodiment, therefore, the coordinate indication key corresponding to the coordinate in each direction to be set can be identified easily and wrong input of coordinates can be prevented effectively. Prevention of mistaken input of coordinates is ensured further as coordinate input by other coordinate indication key is prohibited while coordinate input by one coordinate indication key is accepted. Fig. 9 is a block diagram to show the apparatus for judging effectiveness of set area. Coordinate input signals in transversal direction (perpendicular direction to document exposure direction) and coordinate input signals in longitudinal direction (docuemnt exposure direction) are applied to the memory (91). The apparatus is also provided with a read means (92) to read the coordinates of two points in diagonal direction memorized in the memory (91) as a pair, with a comparing means (93) to compare coordinate values in the same direction by using the coordinates of the two points read by the read means (92) as the input, with an output means (94) to give output signal which indicates that area setting is non-effective by using the output signal which indicate equality of the coordinate values of at least one direction from the comparison means (93) as the input, and also with coordinate input position indicators (80a) (80b) to show area setting condition only when area setting is effective and by using the output signal from the output means (94) as the input. (See Fig.7 as well.) As the operation panel, the one of the composition of Fig. 7 is adopted. Fig. 10 is a flow chart to show operation of the section to judge effectiveness of the area setting device. At step (1) and (2), it is judged whether or not the coordinate values in transversal direction of the pair of points in diagonal direction are equal and whether or not the coordinate values in longitudinal direction of the pair of points in diagonal direction are equal. If either ones are judged equal, the coordinate input position indicators (80a) (80b) of the applicable area indicator (80) are turned off at step (3) to indicate that the set area is non-effective. If both are judged not equal, on the other hand, the coordinate input position indicators (80a) (80b) of the applicable area indicator (80) are turned on at step (4) to indicate that the set area is effective. After processing at step (3) or step (4), it is judged at step (5) and (6) whether or not the coordinate values in transversal direction of a pair of points in diagonal direction of the other area are equal and the coordinate values in longitudinal direction of the other area are equal. If either ones are judged equal, the coordinate input position indicators (80a) (80b) of the applicable area display (80) are turned off at step (7) to indicate that the set area is non-effective. If both are judged not equal, on the other hand, the coordinate input position indicators (80a) (80b) of the applicable area display (80) are turned on at step (8) to indicate that the set area is effective. In other words, the set area shown by A in Fig. 11 has no effective area for edit processing because the coordinate values in transversal direction are equal, while the set area shown by B in the drawing has no effective area for edit processing because the coordinate values in longitudinal direction are equal each other. In such a case, the coordinate input position indicators (80a) (80b) are turned off to indicate that the set area is non-effective. The set area shown by C in the drawing has effective area for edit processing because the coordinate values differ each other in either direction, and the coordinate input position indicators (80a) (80b) are turned on, in this case, to indicate that the set area is effective. Accordingly, area setting operation as a whole is as described below. Coordinate values in transversal direction can be set by operating the coordinate input key (84), the transversal coordinate value adjust key (86), then the coordinate input key (84) again. Then coordinate values in longitudinal direction can be set by operating the longitudinal coordinate value adjust key (87) and the coordinate input key (84). It is also possible to set two area which should be set by performing operations one after another to each one of two points in diagonal direction of the two areas which should be set. Then coordinate setting of each point is completed by operating the input end key (85). Accordingly, it is possible to select setting of one area only by controling the timing to operate the input end key (85). After completing coordinate setting of each required point in the above manner, the judging operation shown in the above flow chart is made, and only the coordinate input position indicators (80a) (80b) of the area display (80) corresponding to the effective set area are turned on to indicate that the set area is effective or not effective. By the above embodiment, therefore, it is easy to set area again by knowing non-effective area setting before image forming if non-effective area is set, which serves to prevent useless image forming operation and waste of copying paper. Fig. 12 is a block diagram of the apparatus to form image in the range corresponding to set area, which applies area width set key signal to the width control section (101), area length set key signal to the length control section (102), the control signals from the width control section (101) and also from the length control section (102) to the blank lamp light control section (103), and controls the number of lamps turned to one of the coordinate input position indicator comprising the blank lamp (33) (See Fig. 6.) as well as on or off time of the lamps. To the length control section (102), clock pulse synchronized with the drive power source (not illustrated) to drive each component of the copying machine, photoreceptor drum (31) in particular, is applied, and the length control section (102) keeps the data to show transfer distance of the photoreceptor drum (31) per unit time, which is determined by the clock pulse and the data to show the distance between the luminescent elements comprising the blank lamp (33). The operation panel is composed as shown in Fig. 7 and the document holder is composed as shown in Fig. 4. Fig. 13 and Fig. 14 show composition of the blank lamp (33). An opening (114) is provided at one side of a long sized box (113) extending in one direction and two or more partition plates (115) are attached to form two or more number of chambers (116) in longitudinal direction, and a luminescent element (117) is attached to each chamber (116). To be more specific, the opening (114) is reduced narrower toward the top so as to be cut sharp in longitudinal direction. In addition, the partition plates (115) are provided with a notch (118) at the top end so as to avoid insufficient light quantity at the boundary. The notch (118) makes the trimmed area slightly smaller and the masked area a little larger in transversal direction, but it causes no problem because the difference is about 1mm maximum. Fig. 15 is a flow chart to explain image forming operation of the main sections. At step (1), the exact position in longitudinal direction is given by the coordinate values when the coordinate input key (84) is operated after operation of the longitudinal coordinate value adjust key (87) multiplied by the distance between the luminescent elements (117) comprising the blank lamp (33). At step (2), the transfer distance on the surface of the photoreceptor drum (31) per unit time which is determined by the clock pulse is read out from the memory (not illustrated), and at step (3), the quotient N and the remainder Q are calculated by dividing the value obtained at step (1) by the value obtained at step (2). Then at step (4), it is judged whether or not the remainder Q is over a half of the distance obtained at the above step (2). If the remainder Q is judged over a half at step (4), the number of clock pulses to keep on or off the luminescent elements (117) is increased by one over the quotient N by increasing the quotient N obtained at step (3) by one at step (5). If the remainder Q is judged not over a half of the distance at step (4), on the other hand, the number of clock pulses for keeping the luminescent elements (117) on or off at the quotient N. To be more specific, at setting of 6mm for the distance between luminescent elements (117) and of 1.27mm for the transfer distance on the surface of the photoreceptor drum (31) per unit time which is determined by the clock pulse, the transfer distance is 6.35mm when the number of clock pulses is 5, which is the closest to the distance between the luminescent elements (117). However, if the number of clock pulses five times larger than the set coordinate value is simply used, the error of 0.35mm is increased in proportion to the increase in the distance from the reference position. As the result, the shape of the area in the copied material actually obtained differs greatly from the shape of the area expected by the operator at area setting. By the above embodiment, however, the error is not accumulated even if the distance from the reference position increases and is kept at 1.27/2 = 0.635mm or less at all times. Accordingly, it is possible to keep the shape of area in the copied material actually obtained close to the shape of area expected by the operator at area setting at a very high accuracy. The difference between both is evident from the following table. By this embodiment, therefore, it is possible to apply trimming and masking to the actually obtained copy in the area similar, at a high accuracy, to the area expected by the operator performing the area setting operation.

Claims: An area setting device comprising a coordinate setting keyboard for setting coordinates of two corresponding diagonal corner points of one or more rectangular areas within a copying zone of a copying apparatus, said keyboard including coordinate setting keys (55; 86, 87) and a display for indicating said coordinates, characterized by memory means (63) arranged in a predetermined order corresponding to the sequence of the corner points of the rectangular areas for memorizing set states and enabling states of coordinate setting operations corresponding to each corner point which can be set, a coordinate input key (57; 84) for enabling the memory means (63) to memorize the set state for coordinates which have been input by the coordinate setting keys (55; 86, 87), first memory control means (66) for controlling the memory means (63) to memorize the enabling state for a first corner point when coordinate input operations have been completed for all desired areas, coordinate input control means (62) for accepting only a coordinate setting key input indicative of the first point among the points for which enabling states have been memorized, judging means (65) for determining whether the next point following said first point in the predetermined order is memorized in the set state or in the enabling state, second memory control means (67) responsive to the determination made by the judging means (65), and to a determination that a coordinate has been input for said first point or no more coordinates are to be input for said first point, for controlling the memory means (63) to memorize the set state for said first point and the enabling state for said next point. An area setting device according to claim 1, further comprising a transparent member (72) to be positioned on a document placed on the copying zone, an area of which is to be set, said member (72) containing coordinate displays (74X, 74Y) in directions crossing each other at right angles marked at specific positions on the transparent member. An area setting device according to claim 2, further comprising an operation panel (5) for inputting image forming conditions and having coordinate input position indicators (52) corresponding to said directions and having coordinate value indicators (53X, 53Y) corresponding to said directions at specific positions on the operation panel. An area setting device according to claim 3, wherein the coordinate displays (74X, 74Y) on the transparent member are provided in different colors for each direction and the corresponding position indicators (52) are provided in the same color for each direction. An area setting device according to claim 3, in which the coordinate value indicator (53) shows coordinate values in the same color as the corresponding coordinate display (74X, 74Y).

Inventors: KAGAWA, TETSUYA DAIICHI IZUMI KOPO, KOBATA, TADASHI, MAESHIMA, MASANOBU, MIYOSHI, JUN, MORIKAWA, YUSUKE, NAKASHIMA, NAOKI, OKADA, HIROMI, SATONAKA, SHINOBU, UMEDA, TADASHI
Applicants: MITA INDUSTRIAL CO., LTD.
Application year: 1986
Main classification: G03G15
IPC codes: G03G15