JP7284642B2 - Optical scanning device and multi-function machine - Google Patents

Description

The present invention relates to an optical scanning device and a multi-function peripheral having the same.

Most of the multi-function peripherals having functions such as document reading function, document copying function, document printing function, document data transmission/reception function, document data input/output function, etc. are equipped with an electrophotographic image forming apparatus.

2. Description of the Related Art In an electrophotographic image forming apparatus, a latent image is formed on a photosensitive drum, which is an image carrier, by laser light modulated by an image signal.

JP-A-11-23988 JP 2015-222295 A JP-A-2005-331657

Here, there is an image forming apparatus that uses a plurality of laser light sources to increase the resolution of printed images. Laser light emitting modules (hereinafter sometimes simply referred to as "modules") containing a plurality of laser light sources are commercially available, but the price of one module is proportional to the number of laser light emitting sources included in one module. , but increases exponentially depending on the laser emission sources contained in one module. Therefore, it is conceivable to use a plurality of modules to reduce the cost. For example, if eight laser light sources are required, it is less costly to use two modules containing four laser light sources than to use one module containing eight laser light sources.

There is an optical scanner using, for example, two sets of modules each having one or more light emitting elements. In such an optical scanning device, these two modules are displaced in the sub-scanning direction in order to obtain a laser beam pitch in the sub-scanning direction of, for example, 42.3 μm. Place them staggered. Therefore, the BD timing at which the light emitted by the light emitting element of the first module scans the BD sensor is very close to the BD timing at which the same light emitting element of the second module scans the same BD sensor. Therefore, the waveform of the light detection signal output from the BD sensor overlaps the waveforms of both BD timings with a slight shift. , it is difficult to obtain the respective BD timings separately.

In the inventions disclosed in Patent Documents 1 to 3, the beams are made to enter one BD sensor in time series, and the detection signals of each beam are separated to obtain the write timing individually. If the directional beam pitch interval is narrow, there is a possibility that the BD sensor will not be able to respond in time, making it impossible to distinguish between the beams. In addition, there is a possibility that the scanning position of each beam in the main scanning direction will be deviated, causing moiré due to interference with the screen, or that the image will be distorted.

In order to solve this problem, if a system is adopted in which the synchronous detection beams are alternately switched for each polygon surface, errors will occur between the polygon surfaces because the polygon mirror is not an exact hexagonal prism.

In order to solve this problem, if a method is adopted in which the synchronization detection beam is switched each time the polygon surface is updated in the cycle of one revolution of the polygon mirror, the rotation unevenness of the polygon motor will have an effect. Moreover, it becomes necessary to increase the maximum count number by increasing the accuracy of the timing counter, and furthermore, the logic circuit becomes complicated.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an optical scanning device having a plurality of laser light emitting modules, capable of performing optical scanning at low cost and with high accuracy, and a multi-function machine having the same. do.

According to the invention,
a first light emitting element that emits light;
a second light emitting element that emits light;
a second scan for converting light emitted from the first light emitting element into first scanning light for scanning an image carrier, and scanning the image carrier with light emitted from the second light emitting element; an optical deflection means for converting into light;
the first scanning light and the second scanning light in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier; a first light receiving element capable of receiving the
the first scanning light and the second scanning light in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier; a second light receiving element capable of receiving the
The first light emitting element is caused to emit light when the first scanning light scans the first light receiving element, and the first light emitting element is caused to emit light when the first scanning light scans the second light receiving element. a first light emitting element emission timing adjusting means for turning off the light emitting element;
The second light emitting element is turned off when the second scanning light scans the first light receiving element, and the second light emitting element is turned off when the second scanning light scans the second light receiving element. a second light emitting element emission timing adjusting means for causing the light emitting element to emit light;
There is provided an optical scanning device comprising:

Further, according to the present invention, there is provided a multifunction machine comprising the optical scanning device described above.

According to the present invention, it is possible to perform optical scanning with low cost and high accuracy.

1 is a conceptual diagram showing the configuration of an optical scanning device according to a first embodiment of the present invention; FIG. 2 is a plan view showing configurations of a first BD sensor, a second BD sensor, and a BD substrate shown in FIG. 1; FIG. 4 is a timing chart for explaining the overall operation of the optical scanning device according to the first embodiment of the invention; FIG. FIG. 5 is a timing chart for explaining the necessity of adjusting the period of scanning light modulation by an image signal of the optical scanning device according to the first embodiment of the present invention; 3 is a plan view showing a patch pattern and the like used for adjusting a period of modulation of scanning light by an image signal of the optical scanning device according to the first embodiment of the present invention; FIG. 6A to 6D are plan views showing modifications of the patch pattern shown in FIG. 5; FIG. 1 is a functional block diagram showing the configuration of an optical scanning device according to a first embodiment of the invention; FIG. 3 is a functional block diagram showing another configuration of the optical scanning device according to the first embodiment of the invention; FIG. 3 is a functional block diagram showing still another configuration of the optical scanning device according to the first embodiment of the invention; FIG. FIG. 11 is a conceptual diagram showing the configuration of an optical scanning device according to a fifth embodiment of the present invention; FIG. 12 is a conceptual diagram showing the configuration of an optical scanning device according to a sixth embodiment of the present invention; FIG. 12 is a conceptual cross-sectional view of a multifunction device according to a seventh embodiment of the invention; FIG. 12 is a functional block diagram of a multifunction device according to a seventh embodiment of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[First embodiment]
Referring to FIG. 1, the optical scanning device according to the first embodiment of the present invention comprises a first LD (first laser diode) 101-1 and a second LD (second laser diode) 101-2. The first LD 101-1 functions as one first light emitting element, and the second LD 101-2 functions as one second light emitting element.

This optical scanning device also includes a first collimator lens 103-1, a second collimator lens 103-2, an incident CYL (incident cylindrical lens) 105, a polygon mirror 107, and an f.theta.

The light emitted from the first LD 101-1 and the second LD 101-2 is converted into parallel light by the first collimator lens 103-1 and the second collimator lens 103-2, and the width is narrowed by the incident CYL 105, and the light deflection means The linear velocity is converted by the fθ lens 109 into scanning light by the polygon mirror 107 as the first scanning light and the second scanning light for scanning the image carrier 740 (photosensitive drum) 740 .

Furthermore, this optical scanning device includes a mirror 111, a BD lens (beam detection lens) 113, a first BD sensor (first beam detection sensor) 115-1, a second BD sensor (second beam detection and a sensor) 115-2 and a BD substrate 117.

The first BD sensor 115-1 and the second BD sensor 115-2 are mounted on the BD substrate 117. FIG.

The first scanning light and the second scanning light also enter the mirror 111 . The first scanning light and the second scanning light reflected here pass through the BD lens 113 and then enter the first BD sensor 115-1 and the second BD sensor 115-2, respectively. A description of how the first scanning light and the second scanning light scan the first BD sensor 115-1 and the second BD sensor 115-2 will be given later.

A third light receiving element 131 capable of receiving light from the first LD 101-1 and the second LD 101-2 is arranged near them. The third light receiving element may be separated into one dedicated to the first LD 101-1 and one dedicated to the second LD 101-2.

Referring to FIG. 2, on the BD substrate 117, a first BD sensor 115-1 and a second BD sensor 115-2 are arranged side by side in the main scanning direction.

Also, the first BD sensor 115-1 and the second BD sensor 115-2 are capable of detecting the first main scanning light and the second main scanning light emitted from the first LD 101-1 and the second LD 101-2, respectively. placed.

With respect to the first main scanning light emitted from the first LD 101-1, the second main scanning light emitted from the second LD 101-2 is viewed in the sub-scanning direction of the first BD sensor 115-1 and the second BD sensor 115-2. to scan downwards.

The first main scanning light emitted from the first LD 101-1 scans the vicinity of the center of the first BD sensor 115-1 as viewed in the sub-scanning direction, and the second main scanning light emitted from the second LD 101-2 is emitted from the second BD sensor. The first BD sensor 115-1 and the second BD sensor 115-2 are staggered in the sub-scanning direction so as to scan the vicinity of the center of 115-2 when viewed in the sub-scanning direction. They may be arranged at the same position when viewed.

Referring to FIG. 3, BD1 is a signal that goes LOW when the first BD sensor 115-1 detects scanning light, and BD2 is a signal that goes LOW when the second BD sensor 115-2 detects scanning light.

APC1 is a signal for controlling light emission/extinction of the first LD 101-1, and the first LD 101-1 emits light when it is LOW. Similarly, APC2 is a signal for controlling light emission/extinction of the second LD 101-2, and the second LD 101-2 emits light when it is LOW.

As shown in FIG. 1, the first main scanning light from the first LD 101-1 is configured to scan the first BD sensor 115-1, the second BD sensor 115-2, and the image carrier 740 in this order in one main scan. ing.

Similarly, the second main scanning light from the second LD 101-1 is configured to scan the first BD sensor 115-1, the second BD sensor 115-2 and the image carrier 740 in this order in one main scanning.

The first LD 101-1 is turned on by APC1 when the first main scanning light passes through the first BD sensor 115-1, and turned off when the first main scanning light passes through the second BD sensor 115-2. controlled.

The second LD 101-2 is turned off by APC2 when the second main scanning light passes through the first BD sensor 115-1, and turned on when the second main scanning light passes through the second BD sensor 115-2. controlled as

Accordingly, the first BD sensor 115-1 generates BD1 as shown in FIG. That is, the first BD sensor 115-1 generates BD1 that changes from HIGH to LOW only at time t1 when the first main scanning light begins to pass through the first BD sensor 115-1.

Also, the second BD sensor 115-2 generates BD2 as shown in FIG. That is, the second BD sensor 115-2 generates BD2 that changes from HIGH to LOW only at time t4 when the second main scanning light begins to pass through the second BD sensor 115-2.

Furthermore, the second LD 101-2 is controlled by the APC 2 so as to be lit during an additional period before the second main scanning light passes through the first BD sensor 115-1.

Specifically, APC1 changes from LOW to HIGH at time t2 when period Tc1 has elapsed from time t1. In addition, APC1 changes from HIGH to LOW at time t10 when period Tc2 has passed from time t1. Furthermore, although it will be repeated, it changes from LOW to HIGH at time t102 when the period Tc1 has elapsed from time t101.

APC2 changes from LOW to HIGH at time t5 when period Td1 has passed from time t4. Also, APC2 changes from HIGH to LOW at time t8 when the period Td2 has elapsed from time t4. Further, at time t9 when the period Td3 has passed since time t4, the voltage changes from LOW to HIGH, and at time t103 when the period Td4 has passed since time t4, the voltage changes from HIGH to LOW. Furthermore, although it will be repeated, it changes from LOW to HIGH at time t105 when the period Td1 has passed from time t104.

The period during which APC1 is LOW from time t10 to time t102 is the lighting time for generating the BD1 signal of the first LD. During this period, the third light receiving element 131 also measures the amount of light for adjusting the emission intensity of the first LD 101-1.

The period during which APC2 is LOW from time t103 to time t105 is the lighting time for generating the BD2 signal of the second LD.

The period during which APC2 is LOW from time t8 to time t9 is the additional period. During this additional period, the third light receiving element 131 measures the amount of light for adjusting the emission intensity of the second LD 101-2.

Next, DATA1 is a first image signal that modulates the first scanning light, and is the first image signal over a period Ta2 from time t6 when the period Ta1 has passed since the time t1 when the first BD sensor 115-1 detected the first scanning light. 1 Scanning light is modulated.

Similarly, DATA2 is a second image signal that modulates the second scanning light, and is the second image signal over a period Tb2 from time t7 when the period Tb1 has passed since time t4 when the second scanning light was detected by the second BD sensor 115-2. 2. Modulate scanning light.

In the above description, the time t5 is determined as the time when the period Td1 has elapsed from the time t4, but instead, it may be determined as the period Td1' from the time t1.

Determining the time t5 based on the time t1 is particularly effective when the initial state is changed to the steady state only by the light emission of the first LD 101-1 while the second LD 101-2 is turned off. Alternatively, it may be obtained in this way.

Next, referring to FIG. 4, when BD1 moves forward in time due to thermal expansion of the optical box and substrate due to temperature change, and the time interval between BD1 and BD2 widens, the first The modulation period of the scanning light is temporally shifted ahead of the modulation period of the second scanning light by the second image signal, and jitter in the horizontal direction occurs in the image.

Although not shown, the same is true when BD1 moves backward in time, and when BD2 moves forward or backward in time.

To avoid this, the periods Ta1 and Tb1 shown in FIG. 3 are adjusted as follows.

A patch pattern as shown in FIG. 5 is formed on an intermediate transfer belt 35 which will be described later.

Referring to FIG. 5, a patch pattern 123-1 is formed on the intermediate belt 35 by the first scanning light from the first LD 101-1, and a patch pattern 123-2 is formed on the intermediate belt 35 by the second scanning light from the second LD 101-2. do.

If the position of the patch pattern 123-1 in the main scanning direction shifts due to the positional shift of the BD1 or the like, the distance T1 in the sub-scanning direction between the two oblique V-shaped lines that can be detected using the registration sensor 121 fluctuates. Specifically, the distance T1 becomes longer as the V moves toward the start point along the main scanning direction, and conversely, the distance T1 becomes shorter as the V moves toward the end point along the main scanning direction. The period Ta1 is adjusted so that this distance T1 is equal to the predetermined distance T10.

Similarly, when the position of the patch pattern 123-2 in the main scanning direction shifts due to the positional shift of the BD2, etc., the distance T2 in the sub-scanning direction between the two oblique V-shaped lines that can be detected using the registration sensor 121 fluctuates. do. Specifically, the distance T2 becomes longer when the V moves toward the start point along the main scanning direction, and conversely, the distance T2 becomes shorter when the V moves toward the end point along the main scanning direction. The period Tb1 is adjusted so that the distance T2 is equal to the predetermined distance T20.

As another adjustment method, both or one of the period Ta1 and the period Tb1 is adjusted so that the distance T1 and the distance T2 are equal. The overall offset may be adjusted separately.

FIGS. 6(a) to 6(d) show modifications of the patch pattern.

Referring to FIG. 7, the optical scanning device according to one configuration example includes a first light emitting element emission timing adjustment section 141-1, a first light emission element emission intensity adjustment section 143-1, a first modulation period adjustment section 145-1, and a first modulation period adjustment section 145-1. 1 light emitting element driving section 147-1 is included.

Similarly, the optical scanning device according to one configuration example includes a second light emitting element emission timing adjustment section 141-2, a second light emission element emission intensity adjustment section 143-2, a second modulation period adjustment section 145-2, and a second modulation period adjustment section 145-2. It includes a light emitting element driving section 147-2.

It is assumed that the optical scanning device includes the first light emitting element 101-1, the second light emitting element 101-2, the first light receiving element 115-1, the second light receiving element 115-2, and the third light receiving element 131. good too.

The first light emitting element emission timing adjustment section 141-1 causes the first light emitting element 101-1 to emit light when the first scanning light scans the first light receiving element 115-1, and the first scanning light When scanning the second light receiving element 115-2, the first light emitting element 101-1 is extinguished.

Further, the first light emitting element light emission timing adjusting section 141-1 controls light emission and extinguishing of the first light emitting element 101-1 based on the time when the first light receiving element 115-1 detects the first scanning light. do.

The first light-emitting element emission intensity adjustment unit 143-1 determines that the first light-emitting element 101-1 to the third light-receiving element 131 receive light during the period in which the first scanning light scans the first light-receiving element 115-1. Based on the light intensity, the intensity of light emitted by the first light emitting element 101-1 is adjusted.

The first modulation period adjusting section 145-1 adjusts the period for modulating the first scanning light with the first image signal based on the time when the first light receiving element 115-1 receives the first scanning light. do.

Further, the first modulation period adjustment unit 145-1 adjusts the start time of the period for modulating the first scanning light with the first image signal from the time when the first light receiving element 115-1 receives the first scanning light. The period up to is adjusted using the first test pattern.

The first test pattern corresponds to patch pattern 123-1 shown in FIGS. When the position of the first test pattern in the main scanning direction changes according to the period up to the start time of the period modulated by the image signal of 2, the second test pattern along the sub-scanning direction at a predetermined position in the main scanning direction The point-to-point distance changes.

The first light emitting element driving section 147-1 provides the output of the first light emitting element emission timing adjusting section 141-1, the output of the first light emitting element emission intensity adjusting section 143-1, and the output of the first modulation period adjusting section 145-1. The first light emitting element 101-1 is driven by the driving signal generated based on .

The second light emitting element emission timing adjustment section 141-2 turns off the second light emitting element 101-2 when the second scanning light scans the first light receiving element 115-1, and the second scanning light The second light emitting element is caused to emit light when scanning the second light receiving element 115-2.

Further, the second light emitting element light emission timing adjusting section 141-2 controls light emission and extinguishing of the second light emitting element 101-2 based on the time when the second light receiving element 115-2 detects the second scanning light. do.

Further, the second light emitting element light emission timing adjusting section 141-2 further adjusts the period during which the second scanning light scans the image carrier 740 and the period during which the first scanning light scans the first light receiving element 115-1. , and an additional period different from the period during which the second scanning light scans the second light receiving element 115-2, the second light emitting element 101-2 is caused to emit light.

The second light emitting element emission intensity adjustment unit 143-2 emits light from the second light emitting element 101-2 based on the intensity of the light received by the third light receiving element 131 from the second light emitting element 101-2 in the additional period. Adjust the intensity of the light to be played.

As described above, the third light receiving element may be separated into a light receiving element dedicated to the first light emitting element 101-1 and a light receiving element dedicated to the second light emitting element 101-2.

The second modulation period adjusting section 145-2 adjusts the period for modulating the second scanning light with the second image signal based on the time when the second light receiving element 115-2 receives the second scanning light. do.

The second modulation period adjustment unit 145-2 adjusts the period from the time when the second light receiving element 115-2 receives the second scanning light to the start time of the period in which the second scanning light is modulated by the second image signal. The period is adjusted using the second test pattern.

The second test pattern corresponds to patch pattern 123-2 shown in FIGS. When the position of the second test pattern in the main scanning direction changes according to the period up to the start time of the period modulated by by It is subject to change.

The second light emitting element driving section 147-2 outputs the output of the second light emitting element emission timing adjusting section 141-2, the output of the second light emitting element emission intensity adjusting section 143-2, and the output of the second modulation period adjusting section 145-2. The second light emitting element 101-2 is driven by the drive signal generated based on .

As already described, the first modulation period adjusting section 145-1 starts the period of modulating the first scanning light with the first image signal from the time when the first light receiving element receives the first scanning light. The period until the time may be adjusted using the first test pattern and the second test pattern. The period from the time to the start time of the period for modulating the second scanning light with the second image signal may be adjusted using the first test pattern and the second test pattern.

FIG. 8 shows an optical scanning device according to another configuration example. In this configuration example, the second light emitting element light emission timing adjusting section 141-2 controls light emission and extinguishing of the second light emitting element based on the time when the first light receiving element 115-1 detects the first scanning light. Control.

FIG. 9 shows an optical scanning device according to still another configuration example. In this configuration example, the second light emitting element emission timing adjustment section 141-2 determines the time when the first light receiving element 115-1 detects the first scanning light and the second light receiving element 115-2 detects the second scanning light. Light emission and extinguishing of the second light emitting element 101-2 are controlled based on either one of the times when the scanning light is detected.

Further, at least when the optical scanning device is not in a steady state, the second light emitting element emission timing adjusting section 141-2 adjusts the second light emission timing based on the time when the first light receiving element 115-1 detects the first scanning light. light emission and extinguishment of the light emitting element 101-2.

[Second embodiment]
In the first embodiment, each of the first LD 101-1 and the second LD 101-2 has only one light emitting element. In contrast, in the second embodiment, each of the first LD 101-1 and the second LD 101-2 is of a module type having a plurality of light emitting elements. When the first LD 101-1 and the second LD 101-2 each include a plurality of light emitting elements, one specific light emitting element of the first LD 101-1 and one specific light emitting element of the second LD 101-2 are used as the first LD. Even if the sensor 115-1 and the second BD sensor 115-2 are controlled to irradiate and the other light emitting elements are controlled not to irradiate the first BD sensor 115-1 and the second BD sensor 115-2 good. Further, in the second embodiment, the third light receiving element 131 receives light emitted by the specific light emitting element of the first LD 101-1 and the specific light emitting element of the second LD 101-2. do.

Timing adjustment using the patch patterns 123-1 and 123-2 and the registration sensor 121 can be performed for each light emitting element. For example, when the first LD 101-1 has four light emitting elements, the BD signal generated using one light emitting element of the first LD 101-1 is used as a reference, and the first to fourth light emitting elements correspond to this. The periods for modulating the first to fourth scanning lights are individually adjusted by the first to fourth patch patterns.

[Third embodiment]
By bringing the first BD sensor 115-1 and the second BD sensor 115-2 as close as possible in the main scanning direction, fluctuations in the distance between the two sensors due to temperature changes can be suppressed. This makes it possible to suppress deviation in the main scanning direction between the image formed by the first LD 101-1 and the image formed by the second LD 101-2 even if the temperature changes.

In particular, mounting the first BD sensor 115-1 and the second BD sensor 115-2 on the same substrate facilitates the above.

Furthermore, the above effects can be enhanced by using a low-expansion substrate such as a glass epoxy substrate for the substrate.

[Fourth Embodiment]
FIG. 2 shows an example in which the first BD sensor 115-1 and the second BD sensor 115-2 are arranged close to each other. In the third embodiment, both sensors are arranged close to each other so that the distance between them in the main scanning direction does not fluctuate with temperature.

However, as long as the distance between them in the main scanning direction does not change with temperature, there is no restriction on the relative positions of the two sensors in the main scanning direction, and both sensors may be spaced apart to some extent.

10(a) to 10( There are three types of c).

In the example of FIG. 10A, the period during which the first scanning light is turned off while passing through the second BD sensor 115-1 overlaps with the period during which the second scanning light is turned off while passing through the first BD sensor 115-2. .

In the example of FIG. 10B, after the period in which the first scanning light is turned off and passes through the second BD sensor 115-1, there is a period in which the second scanning light is turned off and passed through the first BD sensor 115-2. do.

In the example of FIG. 10(c), the period during which the second scanning light is turned off and passes through the first BD sensor 115-2 precedes the period during which the first scanning light is turned off and passes through the second BD sensor 115-1. exist.

In any of these three combinations, the first LD 101-1 emits light when passing the first BD sensor 115-1 and turns off when passing the second BD sensor 115-2. Also, the second LD 101-2 turns off when passing through the first BD sensor 115-1, and emits light when passing through the second BD sensor 115-2.

[Fifth Embodiment]
The fifth embodiment is an extension of the fourth embodiment.

In the fourth embodiment, it is assumed that the first scanning light and the second scanning light are configured to scan the same position in the main scanning direction at different times. In the eighth embodiment, as shown in FIG. 11A, at least for the first BD sensor 115-1 and the second BD sensor 115-2, the first scanning light and the second scanning light are mainly It is configured to scan the same position in the scanning direction at the same time.

As another example, as shown in FIG. 11B, at least for the first BD sensor 115-1 and the second BD sensor 115-2, the first scanning light and the second scanning light are It is configured to scan the same position in the direction at slightly different times.

Even with such a configuration, the first LD 101-1 emits light when passing through the first BD sensor 115-1, and extinguishes when passing through the second BD sensor 115-2. , the first BD sensor 115-1 and the second BD sensor 115-2, the first BD signal and the second BD signal can be normally generated.

[Sixth Embodiment]
It is also possible to treat a plurality of light emitting elements included in the same module in the same manner as light emitting elements included in separate modules and apply the above embodiments.

For example, when using two modules each including four light emitting elements, the first BD sensor and the second BD sensor are increased to the first to eighth BD sensors. The eight light-emitting elements are turned on when passing through the corresponding BD sensor, but turned off when passing through the non-corresponding BD sensor. Then, the period for modulating the scanning light with the image signal is adjusted based on the BD signal output from the corresponding BD sensor.

[Seventh Embodiment]
The seventh embodiment relates to the MFP 800 according to the first to sixth embodiments. 12 and 13 show the configuration of the MFP 800 and the like.

As shown in FIGS. 12 and 13, the MFP 800 includes a document reading device 820 for reading an image of a document, a MFP main body (image forming unit main body) 830 for forming an image on a sheet, a document reading device 820 and a multifunction device. An operation panel section 843 for operating the machine main body 830 and an arithmetic processing section 841 for controlling the document reading device 820 and the multifunction machine main body 830 based on the operation by the operation panel section 843 are provided.

In addition to using the document reading device 820 alone for image reading and using the MFP main body 830 alone for image formation, these can be linked to copy images. Moreover, the multi-function device 800 may include a storage device and a facsimile device (not shown). The storage device can store images read by the document reading device 820 and images received by the facsimile device. The facsimile device can transmit images read by the document reading device 820 and images stored in a storage device, and can receive images from the outside. Furthermore, the multi-function device 800 may include an interface for connecting with a personal computer via a network. A personal computer connected to the multifunction device 800 can use the functions of the multifunction device for the data that it can manage.

The document reader 820 includes an automatic document feeder SPF (Single Pass Feeder) 824 that automatically feeds a document, and a reader main body 822 that reads an image of the document. In addition to the components shown in FIG. 13, document reading device 820 also includes components shown in FIG. 12, although not shown in FIG. Further, as shown in FIG. 12, the reading device main body 822 is provided with a document platen 826 .

The MFP main body 830 includes a sheet feeding unit 10 that feeds sheets, a manual feeding unit 20 that can manually feed sheets, and a sheet fed by the sheet feeding unit 10 or the manual feeding unit 20. and an image forming unit 30 for forming an image.

The sheet feeding portion 10 includes a sheet stacking portion 11 for stacking sheets, and a separation feeding portion 12 for separating and feeding the sheets stacked on the sheet stacking portion 11 one by one. The sheet stacking unit 11 includes a middle plate 14 that rotates around a rotation shaft 13. The middle plate 14 rotates and lifts the sheet upward when feeding the sheet. The separation feeding unit 12 includes a pickup roller 15 that feeds the sheet lifted by the intermediate plate 14, and a separation roller pair 16 that separates the sheets fed by the pickup roller 15 one by one. .

The manual feeding section 20 includes a manual feeding tray 21 on which sheets can be stacked, and a separation feeding section 22 for separating and feeding the sheets stacked on the manual feeding tray 21 one by one. The manual feed tray 21 is rotatably supported by the multi-function machine main body 830, and when manually feeding, it is fixed at a predetermined angle so that sheets can be stacked. The separation feeding unit 22 includes a pickup roller 23 that feeds the sheets stacked on the manual feed tray 21, and a separation roller 24 and a separation pad 25 that separate the sheets fed by the pickup roller 23 one by one. I have.

The image forming unit 30 includes four process cartridges 31Y to 31K for forming yellow (Y), magenta (M), cyan (C), and black (K) images, and photosensitive drums 740Y to 740K, which will be described later. a transfer unit (transfer means) 33 for transferring the toner images formed on the surfaces of the photosensitive drums 740Y to 740K onto a sheet; and a fixing unit 34 for fixing the transferred toner images onto the sheet. and has. The letters (Y, M, C, K) attached to the end of the symbols indicate respective colors (yellow, magenta, cyan, black).

Each of the four process cartridges 31Y to 31K is detachable from the multifunction machine main body 830 and is replaceable. Since the four process cartridges 31Y to 31K have the same configuration except that the colors of the images formed are different, only the configuration of the process cartridge 31Y for forming an image of yellow (Y) will be described, and the process cartridge 31M will be described. Description of ∼31K is omitted.

The process cartridge 31Y includes a photoreceptor drum 740Y as an image carrier, a charger 741Y that charges the photoreceptor drum 740Y, a developing device 742Y that develops an electrostatic latent image formed on the photoreceptor drum 740Y, and a photoreceptor. and a drum cleaner 743Y for removing toner remaining on the surface of the body drum 740Y. The developing device 742Y includes a developing device body (not shown in detail) that develops the photosensitive drum 740Y, and a toner cartridge (not shown in detail) that supplies toner to the developing device body. The toner cartridge is configured to be detachable from the developing device main body, and can be removed from the developing device main body and replaced when the contained toner runs out.

The exposure device 32 includes a light source (not shown) that emits laser light, a plurality of mirrors (not shown) that guide the laser light to the photosensitive drums 740Y to 740K, and the like. The transfer unit 33 includes an intermediate transfer belt 35 that carries the toner images formed on the photoreceptor drums 740Y to 740K, and a primary transfer roller that primarily transfers the toner images formed on the photoreceptor drums 740Y to 740K onto the intermediate transfer belt 35. 36Y to 36K, a secondary transfer roller 37 that secondarily transfers the toner image transferred on the intermediate transfer belt 35 onto a sheet, and a belt cleaner 38 that removes toner remaining on the intermediate transfer belt 35 . The intermediate transfer belt 35 is stretched over a driving roller 39a and a driven roller 39b, and pressed against the photosensitive drums 740Y-740K by the primary transfer rollers 36Y-36K. The secondary transfer roller 37 nips (holds) the intermediate transfer belt 35 with the driving roller 39a, and transfers the toner image carried by the intermediate transfer belt 35 to the sheet at the nip portion N. FIG. The fixing section 34 includes a heating roller 34a that heats the sheet, and a pressure roller 34b that presses against the heating roller 34a.

The operation panel section 843 includes a display section 845 that displays predetermined information, and an input section 847 that allows the user to input instructions to the document reading device 820 and the multifunction machine main body 830 . In this embodiment, the operation panel section 843 is arranged on the front side of the reading device main body 822 . The front side corresponds to the front side of the paper surface of FIG. 12, and the back side corresponds to the back side of FIG.

As shown in FIG. 13, the arithmetic processing unit 841 includes a CPU 841a that drives and controls the sheet feeding unit 10, the manual feeding unit 20, the image forming unit 30, and the document reading device 820, and various programs for operating the CPU 841a. and a memory 841b that stores various information used by the CPU 841a. The arithmetic processing unit 841 integrates and controls the operations of the sheet feeding unit 10, the manual feeding unit 20, the image forming unit 30, and the document reading device 820 based on the operation of the operation panel unit 843 by the user. The sheet is imaged.

Next, an image forming operation (image forming control by the arithmetic processing unit 841) by the multifunction machine 800 configured as described above will be described. In this embodiment, the image forming section 30 forms an image of the read document fed by the automatic document feeding section 824 and read by the reading device main body 822 on the sheet fed by the sheet feeding section 10. An image forming operation will be described as an example.

When the user inputs an image forming start signal to the input unit 847 of the operation panel unit 843, the read document placed on the automatic document feeder 824 by the user is automatically directed to the document reading position. The document is fed, and the image is read by the reading device main body 822 at the document reading position.

When the image of the document is read by the reading device main body 822, the exposure device 32 irradiates a plurality of laser beams corresponding to each of the photosensitive drums 740Y to 740K based on the image information of the read document. At this time, the photoreceptor drums 740Y to 740K are pre-charged by chargers 741Y to 741K, respectively. An image is formed. After that, the electrostatic latent images formed on the photoreceptor drums 740Y to 740K are developed by developing devices 742Y to 742K, and yellow (Y), magenta (M), and cyan (C) images are formed on the photoreceptor drums 740Y to 740K. ) and black (K) toner images are formed. The toner images of respective colors formed on the photosensitive drums 740Y to 740K are superimposedly transferred onto the intermediate transfer belt 35 by the primary transfer rollers 36Y to 36K, and the superimposedly transferred toner images (full-color toner images) are transferred to the intermediate transfer belt. It is conveyed to the nip portion N while being carried by 35 .

In parallel with the image forming operation described above, the sheets stacked on the sheet stacking section 11 are separated one by one by the separation feeding section 12 and fed to the sheet conveying path 26 by the pickup roller 15 . Then, the skew is corrected by the registration roller pair 27 upstream of the nip portion N in the sheet conveying direction, and the sheet is conveyed to the nip portion N at a predetermined conveying timing. A full-color toner image carried by the intermediate transfer belt 35 is transferred to the sheet conveyed to the nip portion N by the secondary transfer roller 37 .

The sheet onto which the toner image has been transferred is heated and pressurized by the fixing unit 34 to melt and fix the toner image, and the sheet is discharged outside the apparatus by the discharge roller pair 18 . Sheets discharged outside the apparatus are stacked on the discharged sheet stacking unit 19 .

When images are formed on both sides of the sheet (the first side and the second side), before the sheet with the image formed on the first side is discharged outside the apparatus, the discharge roller pair 18 is rotated in the reverse direction. Then, the sheet is conveyed to the double-sided conveying path 17 and then conveyed to the image forming section 30 again via the double-sided conveying path 17 . Then, similarly to the first side, an image is formed on the second side and discharged to the outside of the apparatus. Sheets discharged outside the apparatus are stacked on the discharged sheet stacking unit 19 .

The optical scanning device described above can be realized by hardware, software, or a combination thereof. Also, the optical scanning method performed by the above optical scanning device can be realized by hardware, software, or a combination thereof. Here, "implemented by software" means implemented by a computer reading and executing a program.

The program can be stored and delivered to the computer using various types of non-transitory computer readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible discs, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical discs), CD-ROMs (Read Only Memory), CD- R, CD-R/W, semiconductor memory (eg, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (random access memory)). The program may also be delivered to the computer by various types of transitory computer readable medium. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. Transitory computer-readable media can deliver the program to the computer via wired channels, such as wires and optical fibers, or wireless channels.

The invention can be embodied in various other forms without departing from its spirit or essential characteristics. Therefore, each embodiment mentioned above is only an illustration, and should not be interpreted restrictively. The scope of the present invention is indicated by the claims and is not restricted by the text of the specification. Furthermore, all modifications and changes within the equivalent scope of claims are within the scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be used for optical scanning in an electrophotographic image forming apparatus or the like.

101-1 1st LD (first light emitting element)
101-2 Second LD (second light emitting element)
103-1, 103-2 collimator lens 105 incident CYL (incident cylindrical lens)
107 polygon mirror 109 Fθ lens 111 mirror 113 BD lens (beam detection lens)
115-1 1st BD sensor (1st beam detection sensor; 1st light receiving element)
115-2 Second BD sensor (second beam detection sensor; second light receiving element)
117 BD substrate 121 registration sensor 123-1 patch pattern by LD1 123-2 patch pattern by LD2 131 third light receiving element 141-1 first light emitting element emission timing adjustment section 141-2 second light emission element emission timing adjustment section 143-1 second 1 light emitting element emission intensity adjusting section 143-2 2nd light emitting element emission intensity adjusting section 145-1 1st modulation period adjusting section 145-2 2nd modulation period adjusting section 147-1 1st light emitting element driving section 147-2 2nd Light-emitting element driving section 740 Image carrier (photosensitive drum)

Claims (15)

a first light emitting element that emits light;
a second light emitting element that emits light;
a second scan for converting light emitted from the first light emitting element into first scanning light for scanning an image carrier, and scanning the image carrier with light emitted from the second light emitting element; an optical deflection means for converting into light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a first light receiving element capable of receiving light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a second light receiving element capable of receiving light;
The first light emitting element is caused to emit light when the first scanning light scans the first light receiving element, and the first light emitting element is caused to emit light when the first scanning light scans the second light receiving element. a first light emitting element emission timing adjusting means for turning off the light emitting element;
The second light emitting element is turned off when the second scanning light scans the first light receiving element, and the second light emitting element is turned off when the second scanning light scans the second light receiving element. a second light emitting element emission timing adjusting means for causing the light emitting element to emit light;
An optical scanning device comprising
The second light emitting element emission timing adjustment means controls light emission and extinguishing of the second light emitting element based on the time when the first light receiving element detects the first scanning light, and controlling light emission and extinguishing of the second light emitting element based on the time when the light receiving element detects the second scanning light, and when the optical scanning device transitions from an initial state to a steady state. 2. An optical scanning device according to claim 1, wherein light emission and extinguishing of said second light emitting element are controlled based on the time when said first light receiving element detects said first scanning light. The optical scanning device according to claim 1,
A period during which the first scanning light scans the first light receiving element and a period during which the second scanning light scans the second light receiving element are different from each other. Optical scanner. The optical scanning device according to claim 1 or 2,
The first light emitting element emission timing adjusting means controls light emission and extinguishing of the first light emitting element based on the time when the first light receiving element detects the first scanning light. scanning device. a first light emitting element that emits light;
a second light emitting element that emits light;
a second scan for converting light emitted from the first light emitting element into first scanning light for scanning an image carrier, and scanning the image carrier with light emitted from the second light emitting element; an optical deflection means for converting into light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a first light receiving element capable of receiving light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a second light receiving element capable of receiving light;
The first light emitting element is caused to emit light when the first scanning light scans the first light receiving element, and the first light emitting element is caused to emit light when the first scanning light scans the second light receiving element. a first light emitting element emission timing adjusting means for turning off the light emitting element;
The second light emitting element is turned off when the second scanning light scans the first light receiving element, and the second light emitting element is turned off when the second scanning light scans the second light receiving element. a second light emitting element emission timing adjusting means for causing the light emitting element to emit light;
An optical scanning device comprising
The second light emitting element emission timing adjusting means adjusts either the time when the first light receiving element detects the first scanning light or the time when the second light receiving element detects the second scanning light. , wherein the light emission and extinguishing of the second light emitting element are controlled based on the above. The optical scanning device according to claim 4 ,
The second light emitting element emission timing adjusting means adjusts the timing of the second light emitting element based on the time when the first light receiving element detects the first scanning light, at least when the optical scanning device is not in a steady state. An optical scanning device characterized by controlling light emission and extinguishing. a first light emitting element that emits light;
a second light emitting element that emits light;
a second scan for converting light emitted from the first light emitting element into first scanning light for scanning an image carrier, and scanning the image carrier with light emitted from the second light emitting element; an optical deflection means for converting into light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a first light receiving element capable of receiving light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a second light receiving element capable of receiving light;
The first light emitting element is caused to emit light when the first scanning light scans the first light receiving element, and the first light emitting element is caused to emit light when the first scanning light scans the second light receiving element. a first light emitting element emission timing adjusting means for turning off the light emitting element;
The second light emitting element is turned off when the second scanning light scans the first light receiving element, and the second light emitting element is turned off when the second scanning light scans the second light receiving element. a second light emitting element emission timing adjusting means for causing the light emitting element to emit light;
An optical scanning device comprising
a third light receiving element that receives light emitted from the first light emitting element during a period in which the first scanning light scans the first light receiving element;
The first light emitting element emits light based on the intensity of the light received by the third light receiving element from the first light emitting element during the period in which the first scanning light scans the first light receiving element. An optical scanning device, further comprising first light emitting element emission intensity adjusting means for adjusting the intensity of light. a first light emitting element that emits light;
a second light emitting element that emits light;
a second scan for converting light emitted from the first light emitting element into first scanning light for scanning an image carrier, and scanning the image carrier with light emitted from the second light emitting element; an optical deflection means for converting into light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a first light receiving element capable of receiving light;
The first scanning light and the second scanning are performed in a period different from the period in which the first scanning light scans the image carrier and the period in which the second scanning light scans the image carrier. a second light receiving element capable of receiving light;
The first light emitting element is caused to emit light when the first scanning light scans the first light receiving element, and the first light emitting element is caused to emit light when the first scanning light scans the second light receiving element. a first light emitting element emission timing adjusting means for turning off the light emitting element;
The second light emitting element is turned off when the second scanning light scans the first light receiving element, and the second light emitting element is turned off when the second scanning light scans the second light receiving element. a second light emitting element emission timing adjusting means for causing the light emitting element to emit light;
An optical scanning device comprising
The second light emitting element emission timing adjusting means further comprises a period during which the second scanning light scans the image carrier, a period during which the first scanning light scans the first light receiving element, and causing the second light emitting element to emit light in an additional period different from any period during which the second scanning light scans the second light receiving element;
The optical scanning device is
a fourth light receiving element that receives light emitted from the second light emitting element in the additional period;
Second light emitting element emission intensity adjusting means for adjusting intensity of light emitted from said second light emitting element based on intensity of light received by said fourth light receiving element from said second light emitting element during said additional period An optical scanning device, further comprising: The optical scanning device according to any one of claims 1 to 7 ,
a first modulation period adjusting means for adjusting a period for modulating the first scanning light with a first image signal based on the time when the first light receiving element receives the first scanning light;
a second modulation period adjusting means for adjusting a period for modulating the second scanning light with a second image signal based on the time when the second light receiving element receives the second scanning light;
An optical scanning device, further comprising: The optical scanning device according to claim 8 ,
The first modulation period adjusting means adjusts the period from the time when the first light receiving element receives the first scanning light to the start time of the period for modulating the first scanning light with the first image signal. is adjusted using the first test pattern. The optical scanning device according to claim 9 ,
The first test pattern is a period from the time when the first light receiving element receives the first scanning light to the start time of the period in which the first scanning light is modulated by the first image signal. When the position of the first test pattern in the main scanning direction changes accordingly, the distance between two points of the first test pattern along the sub-scanning direction at a predetermined position in the main scanning direction changes. optical scanning device. The optical scanning device according to any one of claims 8 to 10 ,
The second modulation period adjusting means adjusts the period from the time when the second light receiving element receives the second scanning light to the start time of the period for modulating the second scanning light with the second image signal. is adjusted using the second test pattern. 12. The optical scanning device according to claim 11 , wherein
The second test pattern is a period from the time when the second light receiving element receives the second scanning light to the start time of the period in which the second scanning light is modulated by the second image signal. When the position of the second test pattern in the main scanning direction changes accordingly, the distance between two points of the second test pattern along the sub-scanning direction at a predetermined position in the main scanning direction changes. optical scanning device. The optical scanning device according to claim 8 ,
The first modulation period adjusting means adjusts the period from the time when the first light receiving element receives the first scanning light to the start time of the period for modulating the first scanning light with the first image signal. is adjusted using the first test pattern and the second test pattern,
The second modulation period adjusting means adjusts the period from the time when the second light receiving element receives the second scanning light to the start time of the period for modulating the second scanning light with the second image signal. is adjusted using the first test pattern and the second test pattern. 14. The optical scanning device according to claim 13 , wherein
The first test pattern is a period from the time when the first light receiving element receives the first scanning light to the start time of the period in which the first scanning light is modulated by the first image signal. When the position of the first test pattern in the main scanning direction changes accordingly, the distance between two points of the first test pattern along the sub-scanning direction at a predetermined position in the main scanning direction changes,
The second test pattern is a period from the time when the second light receiving element receives the second scanning light to the start time of the period in which the second scanning light is modulated by the second image signal. When the position of the second test pattern in the main scanning direction changes accordingly, the distance between two points of the second test pattern along the sub-scanning direction at a predetermined position in the main scanning direction changes. optical scanning device. A multifunction machine comprising the optical scanning device according to any one of claims 1 to 14 .

Images