JP2001096799A - Imaging apparatus and imaging method, and medium recording imaging control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam printer in which unnecessary waiting time of a user is reduced at the time of starting rotation of a scanner motor for turning a scanner mirror (polygon mirror). SOLUTION: Upon starting print operation, control of a scanner motor is started and an internal timer is started (S101), and then a period signal from an optical sensor is monitored (S102). When a decision is made that a specified scanning period is reached, operation of the timer is stopped (S103) and the time measured by the timer is compared with a specified time t1 (S104). If the measure time is shorter than t1, a time t2 is waited (S105) otherwise a time t3 shorter than t2 is waited (S106). Following to wait (S107), normal print operation is carried out (S108). The wait time may be operated depending on the time measured by the timer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus and an image forming method using a laser beam, such as a laser beam printer, and a recording medium on which an image forming control program is recorded, and more particularly to a scanning control technique.

The image forming apparatus is not limited to a printer, but includes various electronic devices such as a copying machine including a printer mechanism, a facsimile machine, and a multifunction device.

[0003]

2. Description of the Related Art In a laser beam printer, light emitted from a laser light source is reflected by a rotating polygon mirror so that a laser beam modulated by an image signal scans on a photosensitive member. In most laser beam printers, the polygon mirror is stopped before the user instructs a printing operation. When the user instructs to start printing, rotation of the polygon mirror is started.

Now, since the rotation of the polygon mirror has been started,
The operation of the laser beam printer is as shown in the flowchart of FIG. When the rotation of the polygon mirror is started (S601), it is monitored whether or not the rotation speed is within a predetermined range (S602). If it is determined that the rotation speed has reached the predetermined speed, a predetermined time elapses from that time. Wait (S6
03). After a lapse of a predetermined time, it is determined that the polygon mirror is in a usable state (S604).

Here, the reason for waiting for a predetermined time after the predetermined period is reached is that, in the control at the start of rotation, FIG.
This is because, as shown in (2), a certain time is required until the rotation speed of the polygon mirror overshoots a predetermined value and the rotation speed of the polygon mirror stabilizes to the predetermined value. conventionally,
The time from when the speed of the polygon mirror falls within a predetermined range to when it is determined that the polygon mirror is ready for use is set to a predetermined value.

[0006]

However, when the speed of rotation of the polygon mirror is actually taken, as shown in FIG. 7A, the lower limit of the predetermined range after the rotation of the polygon mirror starts. When the time (t1) until reaching the value of (1) is short, the overshoot is large, and the time from when the lower limit value is reached until the polygon mirror becomes usable (t2).
Is long. On the other hand, as shown in FIG. 7B, the time (t) from when the polygon mirror starts rotating until it reaches the lower limit value is reached.
(3) is long, the overshoot is small, and the time (t2) from when the lower limit is reached until the polygon mirror becomes usable is short.

The reason why the time from when the polygon mirror starts rotating until it reaches the lower limit speed is not constant is that the inertia of the apparatus is different due to a difference in environment, a variation in parts, and the like. In particular, when a fluid is used for the bearing of the rotating body, it greatly depends on the environmental temperature. Therefore, if the time from when the polygon mirror starts rotating until it reaches the lower limit is long, the time from when it reaches the lower limit until the polygon becomes usable as in the conventional example is a fixed value. Then, although the polygon mirror is available after time t4, it is only after time t2 that the device is determined to be usable.
That is, the user is forced to have an unnecessary waiting time only for the time t5 shown in FIG. 7B.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to reduce an unnecessary waiting time for a user at the start of rotation of a scanner motor for rotating a scanner mirror (polyhedral mirror). An object of the present invention is to provide a forming apparatus, an image forming method, and a recording medium on which an image forming control program is recorded.

[0009]

In order to achieve the above object, an image forming apparatus according to a first aspect of the present invention includes an emitting unit for emitting a light beam modulated according to an image signal, and an emitting unit for emitting a light beam. Scanning means for scanning a light beam using a reflection rotator, monitoring means for monitoring whether or not the reflection rotator of the scanning means has reached a predetermined range of speed after starting rotation, and A timer for measuring the time from when the reflection rotating body of the scanning unit starts rotating based on the monitoring result of the monitoring unit until the speed reaches the predetermined range,
Waiting time adjusting means for changing a waiting time from when the rotation speed of the reflection rotating body reaches the predetermined range to when it is determined that the reflecting rotator can be used in accordance with the measurement time measured by the time measuring means; and Control means for starting image forming processing after a waiting time set by the adjusting means.

[0010] Here, there is provided a synchronizing signal generating means for generating a synchronizing signal by detecting the light beam on the scanning path of the light beam, and the monitoring means is arranged so that the synchronizing signal has a period within a predetermined range. If it is determined that the timer operation has been performed, the timer operation of the timer unit may be stopped.

The monitoring means inputs speed information proportional to the rotation speed of the reflection rotator output from the scanning means, and the rotation speed of the reflection rotator is set within a predetermined range based on the speed information. Monitoring whether or not the speed has been reached.

Further, the waiting time adjusting means has comparing means for comparing the time measured by the time measuring means with a predetermined time, and as a result of the comparison by the comparing means, the measured time is shorter than the predetermined time. If the measured time is longer than the predetermined time, a first time is set as the waiting time. If the measured time is longer than the predetermined time, a second time shorter than the first time is set as the waiting time. Can be characterized.

Preferably, a plurality of the predetermined times are prepared as boundary values to be compared by the comparing means, and the waiting time adjusting means changes the waiting time in a plurality of stages according to the comparison result of the comparing means. It can be a feature.

The waiting time adjusting means may calculate the waiting time by a predetermined arithmetic expression based on the time measured by the time measuring means.

Further, the waiting time adjusting means may set the waiting time by table lookup based on the time measured by the time measuring means.

In order to achieve the above object, the invention according to claim 8 uses an emitting means for emitting a light beam modulated in accordance with an image signal, and a light rotating means for reflecting the light beam emitted from the emitting means. A monitoring step of monitoring whether or not a speed in a predetermined range has been reached after the reflection rotator of the scanning means has started to rotate; and A time counting step for measuring a time from when the reflection rotating body of the scanning means starts rotating until the speed reaches the predetermined range based on the monitoring result of the monitoring step, and a measuring time counted in the time counting step. A waiting time adjusting step for changing a waiting time from when the rotation speed of the reflection rotating body reaches the predetermined range to when it is determined that the reflecting rotator is usable, and Characterized by a control step of starting an image forming process after waiting through the.

In order to achieve the above object, the invention according to claim 15 uses an emitting means for emitting a light beam modulated in accordance with an image signal, and a light rotating means for reflecting the light beam emitted from the emitting means. And a control medium for controlling an image forming apparatus having a scanning unit for scanning by a computer, the control program instructing the computer that the reflection rotating body of the scanning unit starts rotating. To monitor whether or not the speed has reached a predetermined range, and based on the monitoring result, time the time from when the reflection rotating body of the scanning means starts rotating to when the speed reaches the predetermined range. And changing the waiting time from when the rotation speed of the reflection rotating body reaches the predetermined range to when it is determined that the reflection rotating body is usable according to the measured measurement time,
The image forming process is started after the waiting time.

(Function) In the present invention, a new time-measuring means is provided for measuring the time from when the scanner motor rotating the scanner mirror (polyhedral mirror) starts rotating until the speed reaches the lower limit speed. The time from when the rotation speed of the scanner motor reaches a predetermined range to when it is determined that the scanner motor can be used is changed according to the time counted by the user. Unnecessary waiting time can be reduced.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIGS. 2 and 3 show an example of the configuration of an exposure section of a laser beam printer according to an embodiment of the present invention. FIG. 2A is a top view of the exposed portion, and FIG. 2B is a cross-sectional view taken along line AA of FIG. 2A and viewed from the left. FIG. 3 is a schematic diagram showing the relationship between the signal exchange between the exposure unit and the control unit of the laser beam printer.

As shown in FIGS. 2 and 3, the laser driving unit 203 turns on the laser light source 212 at a predetermined light amount based on the laser driving signal from the control unit 213, and is changed according to the image signal. Emit laser light (light beam).

The cylindrical lens 207 focuses the laser light at a predetermined distance, and a scanner mirror 205 of a polygon mirror is fixed to a rotation axis of the scanner motor 204.
The scanner motor driving unit 202 operates in accordance with the scanner motor control signal from the control unit 213.
Drive control of the rotation of.

The toric lens 208 corrects the light whose focal point has been flattened by the cylindrical lens 207 into a circular shape, and the fθ lens 209 adjusts the scanning speed of the laser beam for scanning on the photosensitive drum (not shown) to be constant. After the correction, the reflection mirror 210 reflects the laser light toward the photosensitive drum.

The optical sensor 211 receives the laser beam reflected by the scanner mirror 205 and outputs it to the control unit 213 as a periodic signal indicating whether or not the laser beam is irradiated on the optical sensor 211. The control unit 213 can know the rotation speed of the scanner motor 204 by analyzing the change of the periodic signal, and at the same time, keeps the rotation speed of the scanner motor 204 at a predetermined speed or maintains the predetermined speed. Thus, a scanner motor control signal is output to the scanner motor drive unit 202.

The laser light emitted from the laser light source 212 in response to the laser drive signal from the control unit 213 is adjusted in focus by a cylindrical lens 207, and then horizontally scanned by a rotating scanner mirror (polyhedral mirror) 205. The periodic signal is detected by the optical sensor 211 at the end position on the scanning path, and a periodic signal is output to the control unit 213. Thereafter, the photosensitive drum is rotated by the reflection mirror 210 through the toric lens 208 and the correction lens of the fθ lens 209. The light is reflected in the direction (not shown) and irradiates the photosensitive drum to form a latent image corresponding to an image signal (or a document) on the photosensitive drum.

The latent image on the photosensitive drum is developed by a developer of a developing device (not shown), and the developed toner image is transferred to a transfer paper and fixed by pressing and heating of a fixing device (not shown). Thereafter, the transfer paper is discharged out of the printer.

Next, referring to the flowchart of FIG.
A control procedure of the exposure unit of the laser beam printer according to the embodiment of the present invention will be described. Now, when the printing operation is started, the control unit 213 controls the scanner motor driving unit 202.
, The control of the scanner motor 204 is started, and an internal timer (not shown) is started (S101).
The control unit 213 monitors the periodic signal from the optical sensor 211 and determines whether the scanning cycle of the laser beam has reached a predetermined cycle (S102).

When the control section 213 determines that the scanning cycle has reached a predetermined cycle, the control section 213 stops the operation of the timer (S103). Next, the time measured by the timer is compared with a predetermined time t1, which is a predetermined time (S104).
If it is shorter than t2, a wait for time t2 is performed (S10
5) If the measured time is longer than t1, t
Wait for t3 time shorter than 2 hours (S10
6).

The control unit 213 determines that the rotation of the scanner motor 204 is in a state required for printing (scanner ready) after the wait (S107), and performs a normal printing operation (S108).

In an apparatus, for example, the time t1 is set to a value of about 3 seconds, the time t2 is set to a value of about 2 seconds, and the time t3 is set to a value of about 1 second. In the present embodiment, only the two-stage control with the time t1 as a boundary is used, but the number of boundary values (corresponding to t1) is increased to change to n (n = 3.4.5...) Stages. It is also possible to determine the wait time from t1 by using an appropriate calculation.

(Second Embodiment) FIG. 4 shows signal transmission and reception between a scanner motor drive unit 202 and a control unit 213 of a laser beam printer according to a second embodiment of the present invention. The second embodiment differs from the first embodiment only in the method by which the control unit 213 determines the rotation speed of the scanner motor 204. Other configurations and the like are the same as those of the first embodiment shown in FIGS. The same is true.

As shown in FIG. 4, the scanner mirror 205
Rotates in conjunction with the scanner motor 204. The scanner motor driving unit 202 controls rotation of the scanner motor 204 according to a scanner motor control signal from the control unit 213. The scanner motor driving unit 204 is the scanner motor 2
The rotation speed information 04 is output to the control unit 213. The rotation speed information referred to here is FG (frequencnc) which is a pulse signal having a frequency proportional to the rotation speed of the scanner motor 204.
y generation) signal.

Next, referring to the flowchart of FIG.
A control procedure of the exposure unit of the laser beam printer according to the present embodiment will be described. Now, when the printing operation is started, the control unit 213 starts controlling the scanner motor 204 and starts an internal timer (not shown) (S).
501). The control unit 213 is a scanner motor driving unit 202
And determines whether or not the rotation speed of the scanner motor 204 has reached a predetermined period (S5).
02).

When the control unit 213 determines that the scanning cycle (rotation speed of the scanner motor 204) has reached a predetermined cycle, it stops the operation of the timer. At this time, the time measured by the timer is set to t1 (S503).

Next, the control unit 213 obtains a time t2 obtained by a certain function f (t1) calculated under t1 (S504). After waiting for the calculated time t2 (S505), the control unit 213 determines that the rotation of the scanner motor 204 is in a state necessary for printing (scanner ready) (S507), and performs a normal printing operation. Is performed (S508).

In one device, the above function f (t1)
Is, for example, as shown below.

[0037]

F (x) = 1: x> 2 (sec) f (x) = − x + 3: 2 ≧ x ≧ 0 The method of determining the time t2 is described in the first embodiment of the present invention. As described above, a plurality of boundary values (x) may be provided to change in stages.

(Other Embodiments) The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), and can be configured as a single device. (For example, a copying machine, a facsimile machine, etc.).

Another object of the present invention is to supply a recording medium (storage medium) recording a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and to provide a computer of the system or the apparatus. Needless to say, the present invention is also achieved when the CPU (or the CPU or the MPU) reads out and executes the program code stored in the recording medium.

In this case, the program code itself read from the recording medium implements the functions of the above-described embodiment, and the recording medium on which the program code is recorded constitutes the present invention.

As a recording medium for recording the program code and variable data such as a table, for example, a floppy disk (FD), hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, A nonvolatile memory card (IC memory card), a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. It goes without saying that an operating system) may perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

[0043]

As described above, according to the present invention,
A new time-measuring means is provided for measuring the time from when the scanner motor rotating the scanner mirror (polyhedral mirror) starts rotating to when the lower-limit speed is reached, and a scanner is provided according to the time measured by the time-measuring means. Since the time from when the rotation speed of the motor reaches the predetermined range to when it is determined that the motor can be used is changed, unnecessary waiting time of the user at the start of rotation in the laser beam printer can be reduced. .

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a control procedure of an exposure unit of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 shows a configuration example of an exposure unit of the laser beam printer according to the first embodiment of the present invention, wherein (a) is a top view of the exposure unit, and (b) is a line AA of (a). It is sectional drawing which cut | disconnected and was seen from the left.

FIG. 3 is a schematic diagram illustrating a relationship between signal exchange between an exposure unit and a control unit of the laser beam printer according to the first embodiment of the present invention.

FIG. 4 is a schematic view illustrating a relationship between an exposure unit and a control unit in a laser beam printer according to a second embodiment of the present invention.

FIG. 5 is a flowchart illustrating a control procedure of an exposure unit of the image forming apparatus according to the second embodiment of the present invention.

FIG. 6 is a flowchart illustrating a control procedure of an exposure unit of an image forming apparatus in a conventional example.

FIG. 7 is a characteristic diagram illustrating a characteristic example of a rotation speed from the start of rotation of a rotary polygon mirror (scanner) in an exposure unit of the image forming apparatus.

[Explanation of symbols]

 202 scanner motor drive unit 203 laser drive unit 204 scanner motor 205 scanner mirror 207 cylindrical lens 208 toic lens 209 fθ lens 210 reflection mirror 211 optical sensor 212 laser light source 213 control unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C362 BA32 BB23 BB25 BB32 BB34 BB38 BB39 2H027 DA35 DE02 DE09 ED04 ED06 EE01 EE02 EE06 EF06 ZA07 2H045 AA01 CA98 CB61 5C072 AA03 BA03 DA23 HA02 HA13 XA11 XB11 RA10

Claims (21)

[Claims] 1. An emitting device for emitting a light beam modulated according to an image signal, a scanning device for scanning a light beam emitted from the emitting device by using a reflecting rotator, and the reflection of the scanning device. Monitoring means for monitoring whether or not a speed within a predetermined range has been reached since the rotation of the rotating body has started, and after the reflection rotating body of the scanning means has started rotating based on the monitoring result of the monitoring means. Timer means for measuring the time until the speed in the predetermined range is reached; and, after the rotation speed of the reflection rotator reaches the predetermined range in accordance with the measurement time measured by the time means, can be used. An image forming apparatus comprising: a waiting time adjusting unit that changes a waiting time until the determination is made; and a control unit that starts an image forming process after the waiting time set by the waiting time adjusting unit. 2. The apparatus according to claim 1, further comprising: a synchronizing signal generating unit configured to generate a synchronizing signal by detecting the light beam on a scanning path of the light beam, wherein the monitoring unit determines that the synchronizing signal has a period within a predetermined range. 2. The image forming apparatus according to claim 1, wherein the timing operation of the timing unit is stopped when the determination is made. 3. The monitoring means inputs speed information proportional to the rotation speed of the reflection rotator output from the scanning means, and based on the speed information, sets the rotation speed of the reflection rotator in a predetermined range. 2. The image forming apparatus according to claim 1, wherein whether or not the speed has reached is monitored. 4. The waiting time adjusting means has a comparing means for comparing the time measured by the time measuring means with a predetermined time, and as a result of the comparison by the comparing means, the measured time is longer than the predetermined time. If the measured time is longer than the predetermined time, a first time is set as the waiting time. If the measured time is longer than the predetermined time, a second time shorter than the first time is set as the waiting time. The image forming apparatus according to claim 1, wherein: 5. A method according to claim 1, wherein a plurality of said predetermined times are prepared as boundary values to be compared by said comparing means, and said waiting time adjusting means changes said waiting time into a plurality of stages according to a comparison result of said comparing means. The image forming apparatus according to claim 4, wherein: 6. The waiting time adjusting means according to claim 1, wherein said waiting time adjusting means calculates said waiting time by a predetermined arithmetic expression based on the time measured by said time measuring means. Image forming device. 7. The image according to claim 1, wherein said waiting time adjusting means sets said waiting time by table lookup based on the time measured by said time measuring means. Forming equipment. 8. An image forming apparatus comprising: an emission unit that emits a light beam modulated in accordance with an image signal; and a scanning unit that scans the light beam emitted from the emission unit by using a reflecting rotator. In the forming method, a monitoring step of monitoring whether or not a speed in a predetermined range has been reached after the reflection rotating body of the scanning means has started rotating; and a monitoring step of the scanning means based on a monitoring result of the monitoring step. A clocking step of measuring the time from when the reflective rotating body starts rotating to when the speed in the predetermined range is reached, and the rotating speed of the reflective rotating body is determined according to the measurement time measured in the clocking step. A waiting time adjusting step of changing a waiting time from when the predetermined range is reached until it is determined that the image forming apparatus can be used; and starting an image forming process after the waiting time set in the waiting time adjusting step. Image forming method characterized by a control step. 9. The image forming apparatus according to claim 1, further comprising: a synchronizing signal generating unit configured to generate a synchronizing signal by detecting the light beam on a scan path of the light beam. 9. The image forming method according to claim 8, wherein the timing operation of the timing step is stopped when it is determined that the cycle has been reached. 10. The monitoring step includes inputting speed information output from the scanning means and being proportional to the rotation speed of the reflection rotator, and adjusting the rotation speed of the reflection rotator to a predetermined range based on the speed information. 9. The image forming method according to claim 8, wherein whether or not the speed has reached is monitored. 11. The waiting time adjusting step includes a comparing step of comparing a time measured by the clocking step with a predetermined time, and as a result of the comparing step, the measured time is longer than the predetermined time. If the measured time is longer than the predetermined time, a first time is set as the waiting time. If the measured time is longer than the predetermined time, a second time shorter than the first time is set as the waiting time. The image forming method according to any one of claims 8 to 10, wherein: 12. A method according to claim 1, wherein a plurality of said predetermined times are prepared as boundary values to be compared in said comparing step, and said waiting time adjusting step changes said waiting time into a plurality of stages according to a comparison result of said comparing step. Claim 11
2. The image forming method according to 1., 13. The waiting time adjusting step according to claim 8, wherein the waiting time is calculated by a predetermined arithmetic expression based on the time measured in the time counting step. Image forming method. 14. The image according to claim 8, wherein in the waiting time adjusting step, the waiting time is set by table lookup based on the time measured in the clocking step. Forming method. 15. An image forming apparatus comprising: an emission unit that emits a light beam modulated in accordance with an image signal; and a scanning unit that scans the light beam emitted from the emission unit by using a reflecting rotator. A control program for controlling by the computer, the control program instructs the computer whether or not a speed in a predetermined range has been reached after the reflection rotating body of the scanning means started rotating. Based on the monitoring result, the time from when the reflection rotating body of the scanning means starts rotating until the speed reaches the predetermined range is measured, and the time is measured according to the measured measurement time. A waiting time from when the rotation speed of the reflection rotator reaches the predetermined range to when it is determined that the reflecting rotator can be used is changed, and after the waiting time, the image forming process is started. Recording medium recording an image forming control program. 16. The image forming apparatus according to claim 1, further comprising: a synchronizing signal generating unit configured to generate a synchronizing signal by detecting the light beam on a scanning path of the light beam. 16. The recording medium according to claim 15, wherein the timing operation of the timing step is stopped when it is determined that the cycle has reached a predetermined range. 17. The control program causes a computer to input speed information output from the scanning means and that is proportional to the rotation speed of the reflection rotator, and the rotation speed of the reflection rotator is determined based on the speed information. The recording medium according to claim 15, wherein whether or not the speed has reached a predetermined range is monitored. 18. The control program causes the computer to compare the time measured in the timing step with a predetermined time, and as a result of the comparison, if the measured time is shorter than the predetermined time, the first And setting the measured time as the waiting time, and when the measured time is longer than the predetermined time, setting the second time shorter than the first time as the waiting time. Item 18. A recording medium on which the image forming control program according to any one of Items 15 to 17 is recorded. 19. The control program causes a computer to prepare a plurality of the predetermined times as the boundary values to be compared, and sets the waiting time in accordance with a comparison result between the measured time and a predetermined time in a plurality of steps. 19. The recording medium according to claim 18, wherein the control program is changed in a plurality of stages. 20. The image forming apparatus according to claim 15, wherein the control program causes a computer to calculate the waiting time by a predetermined arithmetic expression based on the measured time. Recording medium on which a control program for recording is recorded. 21. The image forming apparatus according to claim 15, wherein the control program causes a computer to set the waiting time by a table lookup based on the measured time. A recording medium on which a control program is recorded.