JPH0691928A - Plural beam scanning recording device - Google Patents

Abstract

PURPOSE:To enable readily realizing drive timing control of respective light emitting devices arranged in a matrix pattern and miniaturizing and simplifying a control system. CONSTITUTION:Exposure data ID for eighty beams are caused by a light address counter 14 to be sequentially written into line memories of control units 100 to 1000 allotted for corresponding lines. Reading of the exposure data ID is started on the basis of an outstart signal OTST and a read clock RCK. At this time, read address counters for the respective control units 100 to 1000 start counting with respect to an offset address. As a result, starting of reading of exposure data for a second line is delayed eight clocks relative to that for a first line, and starting of reading of exposure data for a tenth line is delayed seventy-two clocks relative to that for the first line. With respect to respective lines, the read address counters read exposure data ID for eighty beams every one clock to transmit the same to eight row latches. Respective exposure data are added to respective laser diodes in accordance with an exposure position clock ET.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a multiple beam scanning recording apparatus, and more particularly to drive timing control of each beam.

[0002]

2. Description of the Related Art In an apparatus for recording image data by scanning and exposing a photosensitive material with a light beam modulated by image data, a plurality of laser diodes are prepared from the viewpoint of improving recording speed. Moreover, a method of simultaneously scanning a plurality of beams is used. As an arrangement of a plurality of beams (arrangement of laser diodes) and a method of driving each beam used in such an apparatus, Japanese Patent Laid-Open No. 54-3
There is a technique disclosed in Japanese Patent No. 8130.

In this prior art, in order to prevent the formation of gaps between the recording spots, on a straight line forming an angle (except 0 °, 90 °, 180 °) with respect to the main scanning direction, and adjacent to each other. Each beam is arranged so that When such an array is adopted, it is necessary to delay the output timing of each beam by a delay time τ corresponding to the amount of positional deviation between the beam and the reference beam in the main scanning direction.

Therefore, in this conventional technique, a delay circuit is provided for each drive circuit of each laser diode, and a corresponding delay time τ is realized by this delay circuit.

[0005]

In a multiple beam scanning recording apparatus having a beam arrangement as described in the prior art, a method of providing a delay circuit for each beam to delay the output timing is generally performed. ing. This method is simple and is a useful technique when the number of beams is relatively small (several <10) and the delay amount of each beam is relatively small (several clocks (<10)). .

However, recently, the number of beams tends to increase due to the demand for further improvement of the recording speed, and when the number of beams is as large as several tens, the number of delay circuits is correspondingly several tens. Becomes Moreover, since the delay amount increases, the delay circuit itself becomes complicated. Thus, as the number of beams (the number of signals) increases, the amount of delay increases and the delay circuit becomes enormous. Therefore, when the number of beams increases,
The conventional technique has a problem that it cannot sufficiently cope with the problem.

The present invention has been made to overcome the above problems, and even in a scanning recording apparatus having a large number of light emitting elements (the positions of the respective light emitting elements are displaced from each other), each light emitting element is It is an object of the present invention to provide a practical technique that can easily realize control of drive timing and does not enlarge the structure of the control portion.

[0008]

According to a first structure of the present invention, beams are arranged on a straight line having an inclination with respect to the main scanning direction (excluding directions parallel and perpendicular to the main scanning direction). A multi-beam scanning recording apparatus, which is provided with m (m ≧ 2) light emitting elements arranged and records image data by scanning m beams emitted from the light emitting elements in a main scanning direction onto a photosensitive material. , (A) m writable memories provided for each of the m light emitting elements, and (b) image data to be applied to each of the m light emitting elements, sequentially from the same address to the m memory. And (c) a light emitting element corresponding to the memory and a light emitting element arranged at a reference position among the m light emitting elements. Offset address corresponding to the distance in the scanning direction Offset address storing means for storing, means for generating (d) is a timing pulse,
(E) A read control unit that counts the timing pulse with a value corresponding to the offset address as an initial value, and uses the count result as a read address to read image data from a corresponding memory among m memories and give the image data to the light emitting element. It has and.

In the second structure of the present invention, m beams are arranged so that the beams are arranged on a straight line having an inclination with respect to the main scanning direction (excluding directions parallel and perpendicular to the main scanning direction). In a multi-beam scanning recording device, which is provided with a light emitting element of m ≧ 2), scans a photosensitive material with m beams emitted from the light emitting element in the main scanning direction to record image data,
(A) Writable m provided for every m light emitting elements
Number of memories, (b) command generating means for issuing a command for sequentially writing image data to be applied to m light emitting elements to m memories, and (c) provided for each of the m memories. And a light-emitting element corresponding to the memory and m
Stores an offset address corresponding to the distance in the main scanning direction with the light emitting element arranged at the reference position among the individual light emitting elements, and corresponds to the offset address among the addresses of the memory according to the command. A write control means for sequentially writing image data from an address and (d) a read control means for simultaneously starting image data reading from m memories from the head address and supplying the image data to m light emitting elements respectively. ing.

[0010]

With the first configuration of the present invention, the following operation is performed for each of the m memories. First, the writing control means sequentially writes corresponding image data from the same address in the memory. On the other hand, the read control means counts the timing pulse with an offset address corresponding to the distance in the main scanning direction to the light emitting element arranged at the reference position as an initial value, and counts the timing pulse as a read address, and outputs the image from the memory. The data is read and the image data is applied to the corresponding light emitting element.

As a result, the timing at which the image data is applied to the light emitting element is compared with the timing at which the image data is applied to the light emitting element arranged at the reference position.
It will be delayed by the time corresponding to the offset address.

As a result of the above operation being performed for all the memories, m produced when m beams are irradiated onto the photosensitive material.
All the beam spots are arranged in a line in the sub-scanning direction (direction perpendicular to the main scanning direction).

In the second configuration of the present invention, the following operation is performed for each of the m memories. First,
The command generating means issues a command to write the corresponding image in the memory. In response to this instruction, the writing control means stores the image data in the address corresponding to the offset address in the memory. Such an operation is executed for all m memories.

The reading of the image data is started simultaneously by the reading control means for all of the m memories. Therefore, the image data is sequentially read from the memory having the largest offset address to the memory (minimum offset address) for the light emitting element arranged at the reference position. As a result, the timing at which the image data is applied to each light emitting element is delayed by a time corresponding to the offset address as compared with the timing of the light emitting element arranged at the reference position. As a result, all m beam spots on the photosensitive material are arranged in a line in the sub-scanning direction.

[0015]

【Example】

A. Scanning Unit of Multi-Beam Scan Recording Device FIG. 4 is a plan view schematically showing the mechanical configuration of the scanning unit of the multi-beam scanning recording device. The cylinder 3 rotates about the central axis as a rotation axis in the main scanning direction X and the reverse direction -X. The rotary drive mechanism is not shown here. Further, a rotary encoder 4 is installed at the tip of the rotary shaft of the cylinder 3 and outputs a z pulse synchronized with the rotation of the cylinder 3. A photosensitive material (film) 2 is attached to the surface of the cylinder 3 by vacuum suction.

On the other hand, the exposure head 20, while moving along the guide 5 in the sub-scanning direction Y, irradiates and exposes the photosensitive material 2. Here, the movement of the exposure head 20 in the sub-scanning direction Y is performed in synchronization with one rotation of the cylinder 3. The exposure head 20 includes 80 laser diodes, as described later. Therefore, every time the cylinder 3 makes one rotation, image data for 80 lines is recorded on the photosensitive material 2.

B. Arrangement of Light Source and Delay Amount As described above, in this embodiment, 80 laser diodes form the light source of the exposure head 20. It is not realistic to arrange such a large number of laser diodes in a line in the sub-scanning direction Y. Because, at the time of exposure, it is necessary to reduce the laser beam emitted from each laser diode to a desired beam diameter and inter-beam pitch through the reduction optical system. This is because the size is naturally limited.

Therefore, in this embodiment, the light source arrangement shown in FIG. 9 is adopted. With this arrangement, the size of the light source can be reduced, and a light source that can be put to practical use can be realized.

FIG. 9 shows a front view of a light source unit having 80 laser diodes.
The shaded circles 01 to 80 respectively indicate laser diodes LD1 to LD80 or their output beams b1 to b1.
It represents b80. That is, 80 outgoing beams b1
b80 is tilted by an angle θ with respect to the main scanning direction X 10
It forms a matrix of 8 rows. Moreover, the pitch between the two adjacent beams belonging to the same row (for example, the beam b
1 and b2) have a pitch Δx in the main scanning direction X and a pitch Δy in the sub scanning direction Y.

Here, both pitches Δy and Δx are Δy: Δx
= 1: 2 ⁿ (n ≧ 0) is satisfied. In principle, the value of n may be any value as long as it is an integer of 0 or more, but in consideration of drive timing control of each of the laser diodes LD1 to LD80, n = 2 (1: 4), n = 3 (1: 8) or n = 4
(1:16) is suitable. In particular, considering the overall size of the light source (including the lens diameter of the reduction optical system, magnification, etc.) and the fact that a general data transfer bus is based on 8 bits, n = 3 (1: 8) is obtained. Considered to be optimal. Therefore, in this embodiment, the light source is configured so that Δy: Δx = 1: 8.

However, by using such a configuration,
The following problems occur. That is, regarding the eight laser diodes belonging to the same row, each beam is projected onto the photosensitive material 2 at an equal pitch in the sub-scanning direction Y even if they are driven simultaneously, but laser diodes belonging to different rows (for example, When the beams b1 and b2) are driven simultaneously, they are not projected in a line in the sub scanning direction Y. Therefore, it is necessary to change the drive timing of each laser diode for each row. Specifically, it is as follows.

When each laser diode on the first row is used as a reference in the main scanning direction X, each laser diode on the second row needs to be driven with a delay of 8 clocks from the laser diode on the first row. There is. The same applies to the third line, the fourth line, ...
The laser diode in the 0th row may be delayed by 72 clocks. A portion that can realize such a delay amount is a “driving timing control unit” described later, which is the core of the present invention.

The light source unit shown in FIG. 9 is assembled as follows. In the figure, two sets of positioning pins 22 and 23 (10 pieces /
Set) is provided. Moreover, each positioning pin 22,
23 are both pitches Δy and Δx, and are set so as to be on a straight line with an inclination θ. Further, ten stays 24 are prepared. Eight holes are provided in each stay 24 at an equal pitch, and a laser diode is incorporated in each hole. Therefore, by mounting the ten stays 24 on the base block 21 via the positioning pins 22 and 23, respectively, a 10 × 8 matrix beam array inclined at an angle θ is formed.

C. Configuration of Drive Timing Control Unit FIG. 1 shows a drive timing control unit 10 and an exposure head 2.
It is a block diagram showing the relationship with 0. Exposure data ID from workstation 1 (may be RIP etc.)
In addition to the (parallel signal), control signals such as the transfer start signal LST and the data strobe signal STB are transmitted to the drive timing control unit 10. The exposure data ID is an ON / OFF signal (beat map data) for one line (one beam) and is sent in 8-bit units. On the other hand, the transfer start signal LST and the data strobe signal STB are clocks used when writing the exposure data ID into the drive timing control unit 10.

Further, the z pulse signal of the rotary encoder 4 is input to the drive timing control section 10.

The drive timing control unit 10 reads out the written exposure data ID (at this point, a desired delay amount is realized for each of the laser diodes LD1 to LD80) and drives at the timing of the exposure position clock. Drive circuits DRC1 to DRC corresponding to signals V1 to V80
Output to RC80. Each drive circuit DRC1 to DRC
80 are laser diodes LD1 to LD80, respectively.
It is connected to the.

FIG. 2 is a block diagram showing an electrical configuration of the drive timing control unit 10. As shown in the figure,
The drive timing control unit 10 further includes a control unit 10 for each row.
0 to 1000, and as will be described later, the transmitted exposure data ID is the control unit 100 to 100 corresponding to each row.
Written to 1000.

On the other hand, the transfer start signal LST and the data strobe signal STB are input to the sequence control 13. The sequence control 13 is a central part for controlling the operations (writing, reading, exposure) in the drive timing control section 10. That is, the timing signal CK1 for writing the exposure data ID is output from the sequence control 13 to the write address counter 14, and the write address counter 14 outputs the write address signal WA according to the timing signal CK1 to the control units 100 to 100 of each row. Output to 1000.

On the other hand, the z pulse signal is multiplied in the exposure timing generation circuit 15 to create the exposure position clock ET. The exposure position clock ET is once input to the sequence control 13. Exposure data ID
At the time of reading, the sequence control 13 issues the timing signal CK2 to the exposure timing generation circuit 15,
The exposure timing generation circuit 15 receives the timing signal C
According to K2, the outstart signal OTST and the exposure position clock ET are output to the control units 100 to 1000 in each row. The exposure position clock ET is directly given to the control units 100 to 1000 in each row, and is also divided into the read clock RCK via the 1/8 frequency divider 16 and then,
It is given to each control unit 100-1000.

The CPU 11 is for inputting the ten offset addresses stored in the memory 12 to the control units 100 to 1000 of the corresponding rows.

FIG. 3 is a block diagram showing an electrical configuration of the first row control unit 100. Second line control unit 200
The 10th line control unit 1000 also has the 1st line control unit 1
Since it has the same configuration as that of 00, the first-row control unit 100 will be described here as a representative.

The core of the control unit 100 is the line memory 110.
Has two line memories L1 and L2 (8-bit configuration). This is to improve the efficiency of writing / reading the exposure data, that is, the exposure data ID1 in one line memory (for example, L1) (here, the exposure data of each laser diode belonging to the first row is referred to as ID1). This is because the exposure data ID1 written in the other line memory (for example, L2) is to be read out while writing the. As a result, reading and writing to the line memory 110 are completely independent. Each of the line memories L1 and L2 has a write address terminal W and a read address terminal R as the address terminal A, and writing and reading in the line memories L1 and L2 are switched to each other by the switching signal CS.

On the other hand, the first row read address counter 12
0 corresponds to a control unit for reading the exposure data ID1 from the line memory 110, and the read clock RC
K and the outstart signal OTST are the counter 12
It is input to 0. An offset address register 121 is connected to the counter 120. The offset address register 121 is provided with the offset address OS1 (O
S1: 0) is held. The second line control unit 200-
Offset addresses OS2 to OS stored in the offset address registers in the 10th line control unit 1000
10 is -1 to -9, respectively.

Eight latches (first column latch 131 to eighth column latch 138) are connected to the output side of the line memory 110, and each latch 131 to 138 is read from the first row read address counter 120. Address counter clocks ACK1 to ACK8 issued (line memory 1
(Also a clock for reading the exposure data ID1 from 10). These latches 131-
138 is a laser diode L of each column belonging to the first row
10, L20, ..., Exposure data ID 110 for L80,
... for storing the ID 180. Registers 141 to 148 that output drive signals V10 to V80 by converting a parallel signal into a serial signal in synchronization with the exposure position clock ET are connected to the output sides of the latches 131 to 138.

D. Operation of Drive Timing Control Section Exposure Data Writing Based on a transfer instruction from the workstation 1, the exposure data ID for each beam is sequentially stored in the line memory in the control section of each row (here, the line memory L1 of the two memories is used).
Will be stored in). This point
Details will be described based on the timing chart of FIG.
Note that (d) shows the time axis TIME.

First, the 1-line transfer start signal LST is output for each line (for each beam) (FIG. 5).
(A)). Until the 1-line transfer start signal LST is turned on (time t ₁ ) and turned on again (time t ₂ ),
The exposure data ID _ij (i: line number, j: beam number) of one beam is also in units of 8 bits in the same workstation 1.
Sent by. Further, a strobe signal STB having one pulse for each exposure data ID of 8 bits is transmitted from the workstation 1 to the sequence control 13. The strobe signal STB is a signal for instructing to write the exposure data at each timing (time t ₁₁ , t ₁₂ , ...) At which the signal is turned on. Therefore, the sequence control 13 outputs the timing signal CK1 according to the timing of the strobe signal STB, the write address counter 14 counts up the write address, and the line memory (beam j
The write address signal WA is transmitted to the line memory L1) in the control unit of the row i to which the.

Now, assuming that the exposure data ID for one line of the beam b1 is transmitted between times t _{1 and} t ₂ in FIG. 5, within one hour, the exposure data ID for one line of the beam b1 is transmitted. The exposure data ID is sequentially written from address 0 in the line memory L1 of the 10th row control unit 1000. Subsequently, after time t ₂ , the exposure data ID for one line of the beam b2
Are sequentially written from address 0 in the line memory L1 of the ninth line control unit 900. Hereinafter, the exposure data IDs for one line of the beams b3 to b10 are respectively assigned to the eighth row control unit 80.
The addresses 0 to 1 are sequentially written from the address 0 in the line memory L1 of the control unit 100. Next, the exposure data for one line of the beam b11 is again written in order from the address 1 in the line memory L1 of the 10th row control unit 1000. Below, the exposure data IDs for one line of the beams b12 to b20 are respectively 9th to 1st row control units 900 to 100.
Are sequentially written from the address 1 in the line memory L1. Such writing operation is sequentially performed up to the beam b80, and the writing of the exposure data ID is completed.

Therefore, for example, the beams b10, b20, b30, b40, and b5 are assigned to the addresses 0 to 7 of the line memory L1 (110) of the first-row control unit 100, respectively.
The exposure data for one line of 0, b60, b70, and b80 is written. Line memory L of another row
Also for 1, the exposure data for one line of the beam of each column in the row is sequentially stored in each address 0 to 7.

As described above, since the exposure data ID for 80 lines in the main scanning direction X is stored in each line memory L1, the switching signal CS is issued from the write address counter 14 and each row control unit 100, 200, ... 1
000 line memories L1 and L2 are switched. That is, the address terminal A of the line memory L1 is switched from the write address terminal W to the read address terminal R to be in a read state, while the address terminal A of the line memory L2 is in the read state.
Is switched to the write address terminal W, and the writing becomes possible. Then, the exposure data ID for the next 80 lines (exposure data in the main scanning direction X after the exposure head 20 has moved one step in the sub scanning direction Y) is similarly written in the line memory L2.

As a reference, FIG. 7 is an explanatory diagram for clarifying the concept of the exposure data ID for one line.

Reading Exposure Data Reading exposure data written in each line memory
An outstart signal OTST issued from the sequence control 13 via the exposure timing generation circuit 15.
Started by At that time, each line control unit 100-1
Offset address (0--
By 9), the required delay amount is realized for each row. The exposure data ID1 to ID written in the line memory L1 (of each row) will be described below with reference to the timing chart of FIG.
The case of reading 10 will be described. in this case,
As described above, the new exposure data ID is written in the other line memory L2. Further, (g) is a time axis TIME.

First, the address terminal A of the line memory L1
After switching to the read address terminal R, the outstart signal OTST falls from H level to L level at time T ₀ (see FIG. 6A). As a result, the read address counters (120, ...) Of each row enter the standby state.

Next, at time T ₁ , the exposure position clock ET is issued. This exposure position clock ET is 1 /
After being divided by eight, it is transmitted as a read clock RCK to the read address counter (120, ...) Of each row. This is because the exposure data ID1 to ID10 written in each line memory L2 is in units of 8 bits (including eight drawing point information). The output of the exposure position clock ET starts from the exposure start point on the photosensitive material 2. Read address counter (12
0, ...) Starts counting upon receiving this read clock RCK. However, each read address counter (1
, 20) are controlled by the offset address OS, the count of each counter is started as follows.

That is, since the offset address OS1 of the first row control unit 100 is 0, the first row read address counter 120 starts counting from time T ₁ . or,
The offset address OS2 of the second line control unit 200 is -1
Therefore, the read address counter in the second row is -1 = F
Start counting from FFF _H. Since this offset address OS2 = −1 corresponds to the delay amount described above, that is, 8 clocks, the read address counter in the second row starts counting from time T _{2 in} FIG. Similarly, counting is started from the offset address OS3 = −2, OS4 = −3, ... After all, since the last 10 line read address counter is decided to start counting from -9 = FFF7 _H, the reading of the exposure data ID10 from the line memory L1 line 10 control unit 1000, the first row read It starts from a time delayed by 72 clocks (1 clock is one cycle of the exposure position clock ET) with respect to the count time T ₁ of the address counter 120. A desired delay amount of each row is realized by the above count control.

It is necessary to read the exposure data ID1 to ID10 from the line memory L1 of each row between the rising time of the read clock RCK and the next rising time. Further, the exposure data of eight beams is stored in each line memory L1. Therefore, the reading is performed by the eight address counter clocks ACK output from the read address counters (120, ...) Within the time.
1 to ACK8. As a result, the exposure data of the eight beams stored in each line memory L1 are sequentially read and stored in the eight column latches provided for each row.

For example, the reading of the exposure data ID1 in the first row controller 100 is performed as follows based on the flowchart of FIG. That is, at time T ₁₁ , the address counter clock ACK1 for the first column is output to the line memory L1 and the first column latch 131. In response to the rising edge of the address counter ACK1, the exposure data ID 110 (8bi) of the beam b10 in the first row and the first column.
t) is read from the address 0 of the line memory L1,
It is stored in the first column latch 131. Next, at time T ₁₂ , the address counter clock ACK for the second column
2 is output to the line memory L1 and the second column latch 132, and as a result, the exposure data ID 120 (8 bits) of the beam b20 in the first row and second column is read from the address 1 in the line memory L1 and then in the second column. It is stored in the eye latch 132. Thereafter, the address counter clocks ACK3 to ACK8 for the third to eighth columns are sequentially output, and the first row to the third line 3
The exposure data ID130 to ID180 of the beam b30 of the first column to the beam b80 of the eighth column of the first row are sequentially stored in the latches 133 to 138 of the third column. In this way, the exposure data ID1 for eight lines (ID110-ID
180) is read from the line memory every 1 clock,
It is transferred to each of eight latches (registers) 131 to 138.

Although the above description is for the first row control unit 100, the same reading / transferring is performed in the control units 200 to 1000 in the other rows. For example, 2
In the row control unit 200, at time T ₂₁ , the first-column address counter clock ACK1 is output from the second-row read address counter, the exposure data of the beam b9 of the second row and the first column is read, and 1 Transferred to the column latch.
The address counter clocks ACK1 to AC output from the read address counters (120, ...) Of each row.
K8 is synchronized with each other. Therefore, the exposure data ID1 to ID1 of each row realized by the count control described above.
The delay amount of 0 is retained even during this read / transfer.

The exposure data (ID 110 to I) is assigned to all of the first column latches (131, ...) To the eighth column latches (138, ...).
When D180, ...) Is stored, the exposure data (ID110-110) is further stored in the registers (141-148, ...) In the subsequent stage.
ID 180, ...) Is transferred. This transfer is similarly performed in the control units 100 to 1000 of each row. After that, the exposure data ID1 to ID8 from the line memory L1 are read and transferred again for each row.

Exposure: 8-bit exposure signal (ID110 to ID180, ...) Of each beam transferred to each resist (141-148, ...).
Are taken out one by one (image information of one drawing point) in synchronism with the exposure position clock ET.
~ V80 is transmitted to the laser diodes LD1 to LD80. As a result, each laser diode LD1
The LD 80 lights up according to the timing of the corresponding drive signals V1 to V80, and the 80 laser beams b1 to b80
Exposes the photosensitive material 2. Therefore, the 80 beam spots are, as shown in FIG.
They are formed from the exposure start point in a state where they are arranged in a line.

C. Modified Example In the previous embodiment, a matrix light source of 10 rows × 8 columns was used, but a simpler structure of 10 rows ×
The present invention may be applied to a single-row matrix light source. In this case, as in the previous embodiment, the first to eighth column latches (131 to 138, ...) Are connected to the control units 100 to 100 of each row.
It need not be provided within 1000.

In the previous embodiment, all the addresses are sequentially written from the address 0 at the time of writing, and when reading from the line memory, the count start is delayed for each row by the offset address to realize a desired delay amount. Was there. However, conversely, it is also possible to provide a control unit for storing the offset address for each row on the writing side to substantially realize a desired delay amount at the time of writing. That is, when writing to the line memory in the first-row control unit 100A, the offset address OS
From 1 = 0, the exposure data ID1 is written in order from the address 0. In the second line control unit 200A, the exposure data ID2 is written in order from the address 1 from the offset address OS1 = 1.
Similarly, the exposure data ID3 to ID10 are written. However, in this case, it is necessary to start reading (address count) of the exposure data ID1 to ID10 written in the line memory of each row at the same time. As a result, a desired delay amount is realized for each row. As described above, in the present modification, it is not necessary to provide the offset address register on the read side for each row, but it is necessary to provide a means corresponding to it on the write side for each row. One such example is shown in FIG. This figure shows the configuration of the first-row control unit 100A as a representative example of the control units in each row.

[0052]

According to the first configuration of the present invention, a memory is provided for each light emitting element, and image data written in each memory is read based on an offset address and applied to the light emitting element. Shift the drive timing of each element by the desired delay time of each light emitting element (the time required to make the beam spot emitted from the light emitting element on the same sub-scanning direction as the beam spot of the light emitting element arranged at the reference position) Can be made. By using such control, it is not necessary to provide a delay circuit such as a shift register for each light emitting element as in the prior art, and even if the number of light emitting elements increases, the drive timing control system can be easily configured. It can be constructed, and its size can be easily reduced.

The second configuration of the present invention also has the same effect as the first configuration.

Further, in the present configuration, it is not necessary to provide the read control means for each memory as in the first configuration, and the read control means can be shared by the memories, so that the drive timing control system can be miniaturized. This also has the effect of being even more advantageous in achieving the above.

[Brief description of drawings]

FIG. 1 is a block diagram showing a relationship between a drive timing control unit and an exposure head.

FIG. 2 is a block diagram showing a configuration of a drive timing control unit.

FIG. 3 is a block diagram showing a configuration of a first row control unit.

FIG. 4 is an explanatory diagram schematically showing the configuration of a scanning unit.

FIG. 5 is a timing chart showing a control signal at the time of writing.

FIG. 6 is a timing chart showing control signals at the time of reading / transferring.

FIG. 7 is a conceptual diagram showing exposure data and the like for one line.

FIG. 8 is a block diagram showing a modified example.

FIG. 9 is an explanatory diagram showing a configuration of a light source.

FIG. 10 is an explanatory diagram showing an array of beam spots.

[Explanation of symbols]

 10 Drive Timing Control Unit 14 Write Address Counter 100 First Line Control Unit 110, L1, L2 Line Memory 120 First Line Read Address Counter 121 Offset Address Counter 131 to 138 Latch 141 to 148 Register LD1 to LD80 Laser Diode ID Exposure Data

Claims (2)

[Claims] 1. Light emission of m (m ≧ 2) arranged so that beams are arranged on a straight line having an inclination with respect to the main scanning direction (excluding directions parallel and perpendicular to the main scanning direction). A multi-beam scanning recording apparatus comprising an element and scanning m beams emitted from the light emitting element onto a photosensitive material in the main scanning direction to record image data, wherein: (a) every m light emitting elements And (b) write control means for sequentially writing image data to be applied to the m light emitting elements to the m memories from the same address. (C) is provided for each of the m number of memories, and corresponds to a distance in the main scanning direction between a light emitting element corresponding to the memory and a light emitting element arranged at a reference position among the m number of light emitting elements. Memory offset address (D) pulse generating means for generating a timing pulse; and (e) counting timing pulses with a value corresponding to the offset address as an initial value, and using the count result as a read address, m A multi-beam scanning recording apparatus, comprising: a read control unit that reads out the image data from the corresponding memory among the individual memories and applies the read image data to the light emitting element. 2. Light emission of m (m ≧ 2) arranged so that the beams are arranged on a straight line having an inclination with respect to the main scanning direction (excluding directions parallel and perpendicular to the main scanning direction). A multi-beam scanning recording apparatus comprising an element, which scans a photosensitive material with m beams emitted from the light emitting element in the main scanning direction to record image data, wherein: (a) For each of the m light emitting elements M writable memories provided in, and (b) command generating means for issuing a command to sequentially write image data to be respectively applied to the m light emitting elements in the m memories. (C) It is provided for each of the m number of memories and corresponds to the distance in the main scanning direction between the light emitting element corresponding to the memory and the light emitting element arranged at the reference position among the m number of light emitting elements. It stores the offset address, In response to the command, a write control unit that sequentially writes the image data from an address corresponding to the offset address of the memory, and (d) simultaneously starts the image data reading of the m memories from the head address. A plurality of beam scanning recording apparatuses, each of which is provided with a read control unit that supplies the image data to the m light emitting elements.