JPH03101976A - Line printer - Google Patents

Abstract

PURPOSE:To obviate the data edition, to increase the speed of data transfer and to accelerate the printing speed by connecting a plurality of registers to a fixed number of light-emitting elements respectively and connecting a plurality of line memories, in which printing data input are successively stored temporarily, to the registers through data selectors respectively. CONSTITUTION:A line head 29 in which a large number of light-emitting elements 2 are connected continuously to an array is installed, a plurality of registers 31 are bonded with a fixed number of the light-emitting elements 2 respectively, and a plurality of line memories 36, 37, in which printing data input are stored temporarily in succession, are connected to the registers 31 through data selectors 35 respectively. Consequently, a data having a type proper to printing is output by selecting and reading the printing data at a specified address from printing data in the line memories 36, 37 by each data selector 35. Accordingly, printing data input can be stored temporarily in succession to the line memories 36, 37 without rearrangement, thus eliminating the need for data edition requiring a time.

Description

[Detailed description of the invention] Industrial applications The present invention relates to line printers.

2. Description of the Related Art In recent years, line printers are one of the printers developed using electrophotography.

This line printer is a device in which devices such as a charger, line head, developer, transfer device, etc. are arranged close to the circumferential surface of a photosensitive drum. A latent image is formed by exposure using selective light emission from a light emitting element connected to a line head, and this latent image is developed with toner supplied from a developing device and transferred onto printing paper by a transfer device. be.

Although LEDs and the like are used as light-emitting elements in the above-mentioned line heads, they have problems such as difficulty in achieving both light emission intensity and responsiveness. Therefore, it is currently being considered to use an edge-emitting type EL element as a light emitting element for a line head. Therefore, a line head using this edge-emitting type EL element will be explained based on FIGS. 2 and 3. As illustrated in FIG. 3, the edge-emitting EL element 2 of this line head 1 has a thin active layer 3 made of zinc sulfide containing an active element surrounded by dielectric layers 4 and 5 from above and below. Flat plate electrodes 6 and 7 are formed on the upper and lower surfaces of the dielectric layers 4 and 5, and extremely flat light is emitted from the end surface of the active layer 3, which is approximately 100 times more efficient than conventional EL in which the upper surface emits light. It is possible to obtain a luminescence intensity of . Then, as illustrated in FIG. 2, the edge emitting type EL elements 2 having the above-mentioned structure are successively arranged on a substrate 8 using thin film technology, etc., and a rod lens array (not shown) or the like is attached to the line head 1. is formed.

Therefore, for example, a line head 1 in which an AC power source 9 is connected to each edge-emitting EL element 2 via a switching element is connected to the peripheral surface of a photosensitive drum, which is a photosensitive member, together with a charger, a developing device, a transfer device, etc. By arranging it close to the top, an electrophotographic line printer or the like (not shown) can be manufactured. However, when implementing such a line printer, since the edge-emitting type EL element 2 has an extremely large aspect ratio of the beam shape of the emitted light and is flat, a means for correcting this is required.

Therefore, as a device that solves this problem, there is a device proposed by the present applicant in Japanese Patent Application No. 1-97081. Therefore, this device will be explained as a prior art line printer based on the block diagram illustrated in FIG. 4. In the edge-emitting EL printer 10, which is a line printer, an interface l2 to which a printer controller 11 such as another device is connected is connected via a control circuit l6 to which two address counters 13 and 14 and a reference clock l5 are connected. timing controller 17
is connected. Further, the interface l2 is connected via a first data processing circuit 24 to two RAMs 22 and 23, each of which is a line memory in which three states l8 to 21 are connected to an input/output section.
The control circuit 16 and the address counter 13.14 are connected to M22.23 via a selector 25. Further, the RAMs 22 and 23 are the RAMs 22 and 23 that are connected to the data storage device 22 and 23, respectively. It is connected via the three states 20 and 21 to a second data processing circuit 26 to which a processing controller l7 is connected. The data processing circuit 26 also includes latches 27 - 27 m and drivers 28 . It is connected in parallel to the shift registers 31 and 31m connected to the block electrodes 30 and 30n of the line head 29 via 28m and 28m, respectively. Furthermore, the timing controller l7
is the common electrode 32■ to 32m of the line head 29
a common driver 33 connected to the latch 27,
~27m and shift register 31. ~31m. Note that the block electrode 30. The number of each electronic component 27, 38, 31, etc. connected to the common electrode 32. 32m, and the line head 29 has mXn edge-emitting type EL elements 2.
are installed in succession.

In this configuration, in this edge-emitting EL printer 10, print data including a clock signal inputted from the printer controller 11 via the interface l2 is sent to the first data processing circuit 24 every scanning line.
It is compressed by processing such as sorting.

Therefore, this compressed print data is stored in RAM22.2.
The print data is temporarily stored in one of the RAMs 23 and 3 during the printing time of one main scanning line, and at the same time, the print data temporarily stored in advance is outputted from the other RAM 23 and 22 at high speed.

Here, the selection of the RAMs 22 and 23 for temporarily storing print data is performed by the selector 25, which operates according to the timing input from the printer controller 11 to the address counter 13. Further, print data output from the RAMs 23 and 22 is performed according to the control circuit 16 and the address counter 14, which operate in synchronization with a reference clock signal for high-speed output generated from the reference clock 15.

Therefore, this output print data is reprocessed by the second data processing circuit 26 into a form suitable for printing, and the shift register 31. ~31m are sequentially output to the latch 27. ~2
It is held by 7m. And these members 31.27
and the common driver 33 are the timing controller l7
The block electrodes 30, .about.30n and the common electrodes 32, .about.32m each repeatedly output low-voltage and high-voltage drive pulses to the line head 29 a predetermined number of times.

Therefore, in this edge-emitting type EL printer 10, as shown in the timing chart shown in FIG. The line head 29 repeats line emission four times in the width of the scanning line during its lifetime.

As shown in Figure 6, the lines printed in this way are beautiful with minimal jagged edges, and one pixel is formed by four light emitting operations. Therefore, occurrence of white spots in the sub-scanning direction is also prevented.

Problems to be Solved by the Invention The edge-emitting type EL printer 10 as described above forms one main scanning line by emitting line light a plurality of times.
The printed image is beautiful even when using the RAM 2, and even with a structure that repeats line emission like this,
2.23 is switched to sequentially output temporarily stored print data, so the same signal can be repeatedly output without interrupting the input of print data.

However, in the edge-emitting EL printer 10 described above, each R
In order to temporarily store print data for one line in the AMs 22 and 23, it is necessary for the data processing circuit 24 to rearrange the print data input from the printer controller l1 into a form suitable for printing.

Therefore, for example, 512 edge-emitting type EL elements 2 are arranged in series in the line head 29, and eight common electrodes 32. ~
321 and 64 block electrodes 30, to 30. ．． Assume that a matrix wiring is formed by

In this case, the page memory (
(not shown), for example, one page's worth of print data is stored sequentially from the lower address of each byte (8 bits) up to 512 bits, with each pixel being 1 bit, and this is read out line by line. sorted, each RAM2
It will be temporarily stored on 2.23.

Therefore, the structure of the data stored in the page memory is shown in Table. An example is shown in 1.

Data Structure in Table, 1 r Page Memory" Data in the form described above is then rearranged by the data processing circuit 24 and temporarily stored in the RAM 22.23. Therefore, this rearrangement R
The structure of the data stored in AM22, 23 is shown below.
2 is an example.

Table, 2 Data structure J in rRAM 22, 23 1 shift register → Therefore, the 512-bit data temporarily stored in RAM 22, 23 in the form described above is read out one byte at a time from the lower address to the upper address. The data will be transferred to the shift registers 31, 31, respectively.

The above two Tables. 1. 2, the data sequentially stored in the page memory is read line by line by the data processing circuit 24, edited, and then temporarily stored in the RAMs 22 and 23. However, data editing work for such data is complicated and time-consuming, so this edge-emitting EL printer IO has a complicated structure of the data processing circuit 24, RAM 22, 23, etc., resulting in low productivity and low printing speed. It is also becoming difficult to improve

Means for Solving the Problem A line head in which a large number of light emitting elements are arranged in an array is provided, a plurality of registers are each connected to a predetermined number of light emitting elements, and a plurality of registers are used to sequentially temporarily store input print data. Each line memory is connected to a register via a data selector.

A line head in which a large number of light emitting elements are arranged in an array is provided, a plurality of registers are each connected to a predetermined number of light emitting elements, and a plurality of line memories for sequentially temporarily storing input print data are each connected to a data selector. Since each data selector selects and reads the print data at a predetermined address from the print data in the line memory, data in a format suitable for printing is output, and the input print Data can be sequentially temporarily stored in a line memory without rearranging the data, and there is no need for time-consuming data editing.

Example An embodiment of the present invention will be described based on FIG.

Note that the same parts as those of the edge-emitting EL printer 10 illustrated in FIG. 4 will be given the same names and symbols, and the explanation will be omitted. In the edge-emitting type F, L printer 34 which is this line printer, the number of shift registers 31. ~31m each with a data selector 35. ~
35m is connected.

On the other hand, the interface 12 includes RAMs 3 6, 3 6m, 3 7, 37, which are m line memories, respectively.
Two memory blocks 38 and 39 consisting of R A M 3'6, ~3 6 m are connected.
, 37. ~37m are the data selectors 35, ~37m, respectively.
Connected to 35m.

Note that in this edge-emitting type EL printer 34, each data processing circuit 24, 26 is eliminated.

In this configuration, in this edge-emitting EL printer 34, print data input from the page memory of the printer controller 11 is temporarily stored in one of the memory blocks 38 and 39 as it is, and is stored in the other memory block. By outputting print data temporarily stored in advance from 39 and 38 at high speed, printing is performed in the same manner as in the edge-emitting type EL printer 10 described above.

Here, in this edge-emitting EL printer 34, the print data input from the page memory is transferred to the data processing circuit 2.
RAM 363~36m, 37, ~ of one memory block 38.39 without performing data editing by 4.
37m, and are temporarily stored in sequence.

Therefore, like the edge-emitting EL printer 10 described above,
8 common electrodes 32. ~32. and 64 block electrodes 30, to 30. , and 512 edge-emitting EL elements 2 are wired in a matrix and 512 bits of print data is stored in the page memory.
The structure of the print data temporarily stored in 36, -36m, 37, -37m is shown in Table.3 below. Examples 3 to 6 are sequentially illustrated.

Table. 3 “Data structure in first RAM 36., 37,” Tab
le. 4 “Data structure in second RAM36,,37.” Tab
le, 5 “Data structure in third RAM 36j, 37.” Tab
le. 6 r Eighth RAM 36,, 37. Data structure within J? Oh, in Tables 3 to 6 above, the fourth RAM361 374 to the seventh RAM36■37
, are omitted, but it goes without saying that print data is sequentially stored in these RAMs 36 and 37 as well.

The above Tables 3 to 6 and the above Table.
1, the edge-emitting EL of this example
In the printer 34, the print data temporarily stored in each RAM 36, 37 has the same format as the print data output from the page memory, and does not require data editing such as rearrangement.

Therefore, in this edge-emitting type EL printer 34, for example, is it possible to read print data from the memory block 38? In this case, first, the 3-bit select signal (0, 0.0) from the timing controller
．． is output to. Therefore, these data selectors 351
~35. are RAMs 36, to 36., respectively. The data at address Do is selected and read out from the print data stored within. Therefore, these print data are transferred to the shift registers 31, 31, respectively, and used for multiple line emission operations.

Similarly, each data selector 35, to 35
．． is RAM36, ~36. By selecting and reading out the print data at a predetermined address from among the print data in the print data, data in a format suitable for printing is stored in the shift registers 31.about.31.
will be transferred sequentially.

Note that in the edge-emitting type EL printer 34 of this embodiment, similarly to the edge-emitting type EL printer 10 described above, by providing two memory blocks 38 and 39, temporary storage and output of print data are performed alternately. This allows for line emission to be performed multiple times without interrupting data input. However, even if there is only one memory block, for example, data editing such as rearranging is not required and the print data transfer speed is high, so it is possible to improve the printing speed.

Therefore, since the edge emitting type EL printer 34 of this embodiment has a high print data transfer speed, it is also possible to increase the density of printing by increasing the number of edge emitting type EL elements 2.

Furthermore, although the edge-emitting EL printer 34 has been illustrated here as this embodiment of the line printer, the present invention is not limited thereto and can be applied to various line printers.

Effects of the Invention As described above, the present invention provides a line head in which a large number of light emitting elements are arranged in an array, connects a plurality of registers to a predetermined number of light emitting elements, and sequentially temporarily stores input print data. By connecting a plurality of line memories for storage to registers through data selectors, each data selector selects and reads print data at a predetermined address from the print data in the line memory, thereby creating a format suitable for printing. data can be output and the input print data can be sequentially temporarily stored in the line memory without rearranging, etc., and time-consuming data editing is not required.
Fast data transfer can improve printing speed,
Since circuit components for data editing can be omitted, the circuit structure is simple and the productivity of the device is high.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a perspective view of an edge-emitting type EL element array, Fig. 3 is a perspective view of an edge-emitting type EL element, and Fig. 4 is a Special application Hei 1
5 is a timing chart, and FIG. 6 is an explanatory diagram of a printed image.

Claims (1)

[Claims] A line head in which a large number of light emitting elements are arranged in an array is provided, a plurality of registers are each connected to a predetermined number of the light emitting elements, and a plurality of line memories for sequentially temporarily storing input print data are each connected to a data selector. A line printer, characterized in that it is connected to the register via a line printer.