JP3946037B2 - Multi-beam light source device, optical scanning device, and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical scanning device used for a writing system in a recording apparatus such as a digital copying machine, a laser printer, and a laser facsimile, and in particular, simultaneously scans a surface to be scanned such as a photoreceptor with a plurality of light beams. The present invention relates to a multi-beam light source device, an optical scanning device, and an image forming apparatus that significantly improve a recording speed.
[0002]
[Prior art]
As a technique for improving the recording speed in an optical scanning apparatus used in an optical writing system of a recording apparatus such as a laser printer and a laser facsimile, the rotational speed of a rotating polygon mirror, that is, a polygon mirror, as an optical deflector used as a deflecting means There is a way to raise. However, in this method, the durability, noise, vibration, modulation speed of the semiconductor laser, and the like of the motor used for rotational driving of the polygon mirror become problems, and the recording speed is limited.
In view of this, a multi-beam optical scanning device has been proposed that improves the recording speed by simultaneously scanning a plurality of light beams and simultaneously recording a plurality of lines. For example, as disclosed in Japanese Patent Application Laid-Open No. 56-42248, there is a method of using a semiconductor laser array in which a plurality of light emitting portions are arranged in an array as a light source.
[0003]
In a normal case, the light output of the semiconductor laser is controlled by detecting the light output using the scanning time outside the image area for each scanning line and setting the applied current amount and the like by feedback control. In the above-described semiconductor laser array disclosed in Japanese Patent Laid-Open No. 56-42248, there are a plurality of light emitting units, but since the sensor for detecting the light output is common, output setting control by feedback based on the detection of the light output is performed in time series. Must be done. Moreover, the time required for this process tends to increase as the number of light emitting portions in the semiconductor laser array increases. For this reason, although the light output cannot be fed back in real time as in a normal semiconductor laser, the output is likely to fluctuate due to the crosstalk, etc. Highly accurate light quantity control cannot be performed. Moreover, due to its particularity, it has the disadvantage of being expensive. About these points, it becomes further disadvantageous as the number of light emission parts increases.
[0004]
On the other hand, a technique in which light beams are synthesized using a plurality of general-purpose semiconductor lasers is disclosed in Japanese Patent Laid-Open Nos. 2000-75526, 2000-75527, 2001-13432, and the like. Various proposals have been made. According to the method of synthesizing a light beam using a plurality of general-purpose semiconductor lasers, there is no problem that a semiconductor laser array has, but on the other hand, the environment is caused by the complexity of the configuration. The problem is that the stability is reduced. In particular, when the structure of the light source device is complicated, the posture of the light source device itself changes due to a temperature change, deformation, twist, and the like. When such posture change, deformation, twisting, etc. of the light source device occur, the interval in the sub-scanning direction of the light spot on the surface to be scanned is greatly deviated from the desired interval, resulting in deterioration of the image formed and recorded. I will invite you.
[0005]
[Problems to be solved by the invention]
As described above, in the method of synthesizing a light beam using a plurality of general-purpose semiconductor lasers described in JP-A-2000-75526, JP-A-2000-75527, JP-A-2001-13432, and the like. There is a problem that the environmental stability is very low. In particular, due to the complexity of the structure of the light source device, the posture of the light source device itself changes, deforms, twists, etc. due to temperature changes, and the optical spot on the scanned surface has a large gap in the sub-scanning direction. Cause deterioration of the image.
The present invention has been made in view of the above-described circumstances. In a multi-beam light source device, an optical scanning device, and an image forming apparatus that constitute a multi-beam light source using a plurality of general-purpose semiconductor lasers, reliable and stable image reproducibility is provided. It is an object of the present invention to provide a multi-beam light source device, an optical scanning device, and an image forming apparatus that can ensure the above.
[0006]
[Means for Solving the Problems]
  In particular, the object of claim 1 of the present invention is, CoveredIt is possible to accurately set the scanning line interval on the scanning plane,The scanning line pitch in the sub-scanning direction on the surface to be scanned is almost unaffected by environmental fluctuations due to environmental temperature fluctuations, and has excellent environmental stability and low cost.AssemblingAlsoAn object of the present invention is to provide a multi-beam light source device that can be improved.
  BookClaims of the invention2An object of the present invention is to provide a multi-beam light source device that can realize further higher density.
  Claims of the invention3An object of the present invention is to provide a multi-beam light source device that can realize further higher density.
  Claims of the invention4The object of the present invention is to provide an optical scanning device that can accurately set the scanning line interval on the scanning surface of the multi-beam optical scanning with an inexpensive configuration and is excellent in environmental stability and assemblability. is there.
  Claims of the invention5The object of the present invention is to provide an image forming apparatus that can accurately set the scanning line interval on the scanning surface of the multi-beam optical scanning with an inexpensive configuration and is excellent in environmental stability and assemblability. is there.
[0007]
[Means for Solving the Problems]
  In order to achieve the above-described object, a multi-beam light source device according to the present invention described in claim 1 is provided.
  In a multi-beam light source device used in an optical scanning device that scans simultaneously using a plurality of light beams after coupling a plurality of light beams emitted from a plurality of light sources by a plurality of coupling lenses,
  A plurality of holes that hold the plurality of light sources in a detachable manner;
  A protruding member that protrudes from the support and bonds the plurality of coupling lenses;
Equipped with,
  in frontProtrusion memberShapeIs a length in a direction substantially perpendicular to the direction of the bonding axis for bonding the plurality of coupling lenses and substantially parallel to the lens surface of the coupling lens.But, Approximately equal to or greater than the outer diameter of the coupling lensAnd the length of the protruding member increases and widens toward the support side.It is characterized by that.
[0008]
  Claim2The multi-beam light source device according to the present invention described in 1 is characterized in that the plurality of light sources include a semiconductor laser array element having a plurality of light emitting portions.
  Claim3The multi-beam light source device according to the present invention described in 1 is characterized in that two or more supports are provided, and the supports are fixed to a common base.
[0009]
  Claim4In order to achieve the above-described object, the optical scanning device according to the present invention described in 1) is provided.
  A plurality of light beams emitted from the light source device are combined into a plurality of line images that are long in the main scanning direction and separated in the sub-scanning direction in the vicinity of the deflection reflection surface position of the optical deflector by a common line image imaging optical system. Image
  Deflected at the same angular velocity simultaneously by the optical deflector,
  The deflected beam is condensed as a plurality of light spots separated in the sub-scanning direction on the surface to be scanned by a common scanning optical system,
  In a multi-beam type optical scanning device that simultaneously scans a plurality of scanning lines with the plurality of light spots,
  Claim 1 to claim as the light source device.3The multi-beam light source device according to any one of the above is used.
[0010]
  Claim5In order to achieve the above-described object, the image forming apparatus according to the present invention described in 1 is provided.
  In an image forming apparatus for forming a latent image by scanning a scanning surface of a photosensitive image carrier with an optical scanning unit, and visualizing the latent image with a developing unit to obtain an image.
  The optical scanning unit for scanning the surface to be scanned of the image carrier as claimed in claim 1.4The optical scanning device is used.
[0011]
[Action]
  That is, in the multi-beam light source device according to claim 1 of the present invention, a plurality of light beams emitted from a plurality of light sources are respectively coupled by a plurality of coupling lenses, and then simultaneously scanned using the plurality of light beams. A multi-beam light source device used for an optical scanning device to perform, wherein the plurality of light sources are respectively press-fitted into a plurality of holes arranged in the same support and are detachably held, and the plurality of cups A ring lens is bonded to a projecting member projecting from the support, and the projecting memberShapeIs a length in a direction substantially perpendicular to the direction of the bonding axis for bonding the plurality of coupling lenses and substantially parallel to the lens surface of the coupling lens.But, Approximately equal to or greater than the outer diameter of the coupling lensAnd the length of the protruding member increases and widens toward the support side..
  With such a configuration, when configuring a multi-beam light source using a plurality of general-purpose semiconductor lasers, a reliable and stable image reproducibility can be ensured.And easy to assembleIt is possible to accurately set the scanning line interval on the surface to be scanned, and it is possible to improve environmental stability and assemblability.
[0012]
  Claims of the invention2In the multi-beam light source device according to, the plurality of light sources includes a semiconductor laser array element having a plurality of light emitting units.
[0013]
With such a configuration, it is possible to realize further higher density.
[0014]
  Claims of the invention3In the multi-beam light source device according to, two or more supports are provided, and the supports are fixed to a common base.
  Such a configuration makes it possible in particular to achieve higher density.
  Claims of the invention4In the optical scanning device according to the above, a plurality of light beams emitted from the light source device are separated in the main scanning direction in the vicinity of the deflection reflection surface position of the optical deflector by the common line image imaging optical system and separated in the sub scanning direction. Formed as a plurality of line images, deflected simultaneously at the same angular velocity by the optical deflector, and the deflected beam as a plurality of light spots separated in the sub-scanning direction on the surface to be scanned by a common scanning optical system A multi-beam type optical scanning device that condenses and simultaneously scans a plurality of scanning lines with the plurality of light spots, and as the light source device, the light source device according to any one of claims 1 to 4. A multi-beam light source device is used.
  With such a configuration, it is possible to accurately set the scanning line interval on the scanning surface of the multi-beam optical scanning with an inexpensive configuration, and it is possible to obtain excellent environmental stability and assemblability.
[0015]
  Claims of the invention5The image forming apparatus according to the present invention is an image forming apparatus that forms a latent image by scanning a scanning surface of a photosensitive image carrier with an optical scanning unit, and visualizes the latent image with a developing unit to obtain an image. The optical scanning unit for scanning the surface to be scanned of the image carrier as claimed in claim 1.4The optical scanning device is used.
  With such a configuration, it is possible to accurately set the scanning line interval on the scanning surface of the multi-beam light scanning with an inexpensive configuration, and to obtain an image forming apparatus having excellent environmental stability and assemblability. be able to.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, based on an embodiment of the present invention, a multi-beam light source device, an optical scanning device, and an image forming apparatus of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
1 to 3 show the configuration of the multi-beam light source device according to the first embodiment of the present invention. 1 is an exploded perspective view showing the configuration of the multi-beam light source device, FIG. 2 is a plan cross-sectional view showing a vertical cross section seen from the top surface in the assembled state of the multi-beam light source device of FIG. 1, and FIG. It is an elevation sectional view showing the longitudinal section seen from the side in the assembly state of a multi-beam light source device.
The multi-beam light source device shown in FIGS. 1 to 3 includes semiconductor lasers 11 and 12, collimator lenses 13 and 14, a support 15, a support protrusion 17, a holder member 19, and a screw 23.
[0017]
This multi-beam light source device is configured as a two-beam light source device using two semiconductor lasers 11 and 12 each composed of a single-beam semiconductor laser. Corresponding to these semiconductor lasers 11 and 12, collimator lenses 13 and 14 as coupling lenses are provided. These collimator lenses 13 and 14 are paired with each other, and couple the emitted light from the semiconductor lasers 11 and 12 to the scanning optical system as, for example, parallel light. In this embodiment, collimator lenses 13 and 14 are used as coupling lenses, and the light emitted from the semiconductor lasers 11 and 12 is parallel light. However, the divergence required for the light beam emitted from the coupling lens is used. Since the shape depends on the design of the scanning optical system or the like, it can be a convergent light beam or a divergent light beam corresponding to the design of the scanning optical system or the like.
[0018]
In addition, the multi-beam light source device is provided with a support 15 that holds these members together. The support 15 is made of, for example, aluminum die-casting, and has two stepped fitting holes 16 for press-fitting and supporting the semiconductor lasers 11 and 12 in parallel in the main scanning direction at intervals of 8.74 mm. It has been. The semiconductor lasers 11 and 12 are each press-fitted and attached to the two fitting holes 16 from the back side of the support 15. Further, a support protrusion 17 as a protrusion member protrudes from the center of the front surface of the support 15, and the support protrusion 17 has a collimator coaxial with the inner surfaces of the two fitting holes 16. Lens-shaped U-shaped support portions 17a and 17b having curved surfaces corresponding to the outer shapes of the lenses 13 and 14 are formed (see FIG. 4). Here, the curved surfaces of the U-shaped support portions 17a and 17b are inclined with an angle α between them, and the axis of the fitting hole 16 corresponding to each of the U-shaped support portions 17a and 17b is also provided. A tilt angle α is given between them. The collimator lenses 13 and 14 are fixed to the support 15 by filling the U-shaped support portions 17a and 17b with an ultraviolet curing adhesive 18 and curing it.
[0019]
In this case, as shown in FIG. 2, the optical axes of the collimator lenses 13 and 14 are inclined with respect to each other and intersect at an angle α. By arranging a polygon mirror as an optical deflector in the vicinity of this intersecting point, the light spot is separated on the surface to be scanned with a gap in the main scanning direction, and it is possible to independently obtain a synchronization signal. It becomes.
A holder member 19 is provided for holding the support body 15 that holds the semiconductor lasers 11 and 12 and the collimator lenses 13 and 14 together.
The holder member 19 is provided with a cylindrical portion 20 projecting from the center of the front surface so as to be pivotably positioned on a predetermined support portion with the optical axis C of the scanning optical system as the rotation center. A relief opening 21 for inserting the support protrusion 17 and the collimator lenses 13 and 14 is formed. The support 15 is fixed to the holder member 19 by screwing the screw 23 inserted through the through-hole formed in the holder member 19 into the screw hole 22 formed in the support 15. Here, the support 15 is positioned and fixed to the holder member 19 so that the semiconductor lasers 11 and 12 and the collimator lenses 13 and 14 are symmetrically arranged with respect to the optical axis C, respectively.
[0020]
According to such a configuration, the sub-scanning direction of the beam spots of the semiconductor lasers 11 and 12 can be set simply by rotating the holder member 19 with the optical axis C of the scanning optical system as the rotation center and appropriately setting the tilt amount. Can be easily and accurately adjusted to a predetermined value.
By the way, when the light beam is incident on the polygon mirror at an angle α in the main scanning direction, there is a disadvantage that the curvature of field in the sub scanning direction is inclined. When the curvature of field is inclined, the change in the beam spot diameter with respect to the positional deviation on the optical axis in the vicinity of the focal point becomes large, the focal depth becomes shallow, and the scanning optical system becomes weak against environmental fluctuations. Therefore, the angle α is preferably as small as possible. For this purpose, the distance d between the U-shaped support portions 17a and 17b in FIG. In this embodiment, the distance d is set to 1 mm to 2 mm, for example. However, when the distance d is reduced in this way, the collimator lenses 13 and 14 are likely to be displaced due to deformation due to environmental fluctuations. If such a deformation is a deformation in a specific direction, it is possible to add some correction. However, the method of the deformation is not uniform and varies in a very complicated manner depending on the material and shape. .
[0021]
If the collimator lenses 13 and 14 are displaced as described above, the interval between the scanning lines due to the light spot formed on the surface to be scanned becomes non-uniform, resulting in image deterioration.
Therefore, it is necessary to suppress such deformation, but as a result of repeating the experiment by forming support portions of various shapes, the coupling lens depends on how to set the dimension H and the angle φ shown in FIG. It has been found that the deformation of the collimator lenses 13 and 14 can be effectively suppressed. As shown in FIG. 4, the dimension H in FIG. 3 is substantially perpendicular to the direction of the bonding axis of the collimator lenses 13 and 14 in the support protrusion 17, that is, substantially perpendicular to the arrangement direction of the collimator lenses 13 and 14. The length in the direction substantially parallel to the lens surface where the optical axes of the collimator lenses 13 and 14 intersect perpendicularly is shown.
[0022]
The support protrusion 17 is substantially perpendicular to the direction of the bonding axis for bonding the collimator lenses 13 and 14 and is parallel to the dimension H toward the base of the support protrusion 17 in the thickness direction of the collimator lenses 13 and 14. The dimension of the direction gradually increases and expands, and the expansion angle toward the bottom is φ. As a result of the experiment, it has been confirmed that if at least the dimension H is approximately equal to or greater than the outer diameter of the collimator lenses 13 and 14 (see FIG. 4), it is relatively stable against environmental fluctuations. In this embodiment, the dimension H is set to 6.8 mm for the collimator lenses 13 and 14 having an outer diameter of 5.8 mm. Furthermore, it was confirmed that if the expansion angle φ of the tapered shape in which the skirt of the support protrusion 17 expands is 10 ° or more, it is more stable against environmental fluctuations. Therefore, in this embodiment, the spread angle φ is 12.5 degrees. FIG. 5 shows how much the scanning line pitch in the sub-scanning direction on the surface to be scanned fluctuates due to environmental variation. As is apparent from FIG. 5, when the environmental temperature was changed to 10 ° C., 25 ° C., and 50 ° C. and measured, the scanning line pitch in the sub-scanning direction was almost affected by environmental fluctuations in the structure of this embodiment. I understand that there is no.
With such a configuration, it is possible to accurately set the scanning line interval on the surface to be scanned with an inexpensive configuration, and it is possible to realize a multi-beam light source device excellent in environmental stability and assemblability. .
[0023]
<Second Embodiment>
FIG. 6 is an exploded perspective view showing the configuration of the multi-beam light source device according to the second embodiment of the present invention. The multi-beam light source device of this embodiment is configured as a four-beam light source device intended to further increase the speed.
The multi-beam light source device shown in FIG. 6 includes semiconductor lasers 31, 32, 33, 34, collimator lenses 35, 36, 37, 38, support bodies 39, 40, support protrusions 41, 42, prism 51 and holder member 55. It has. The part composed of the semiconductor lasers 31 and 32, the collimator lenses 35 and 36, the support 39 and the support projection 41, and the part composed of the semiconductor lasers 33 and 34, the collimator lenses 37 and 38, the support 40 and the support projection 42 1 and 3 are configured in the same manner as the portion including the semiconductor lasers 11 and 12, the collimator lenses 13 and 14, the support 15, and the support protrusions 17 in FIGS. 1 to 3.
[0024]
  The support protrusions 41 and 42 in the supports 39 and 40 are configured such that H = 5.8 mm in FIG. 1 to FIG. 3 and φ = 12.5 °. These supports 39 and 40 may be fixed to a common base (not shown) and held together.
  The prism 51 has a parallelogram column part 52, a triangular column part 53, and a half-wave plate 54, and scans a plurality of light beams emitted from the respective emission points of the semiconductor lasers 31 to 34 of the scanning optical system. Beam combining means for emitting the light beam close to the optical axis C in the sub-scanning direction is configured. Of prism 51Parallelogram column 52A half-wave plate 54 is provided at an incident portion from the semiconductor lasers 33 and 34 in FIG.
[0025]
The light emitted from the semiconductor lasers 33 and 34 is reflected by the oblique side surface of the parallelogram-shaped column portion 52 and then further reflected by the boundary surface with the triangular column portion 53, thereby passing through this triangular column portion 53 portion. The light emitted from the semiconductor lasers 31 and 32 is emitted from the prism 51 as being close to the sub-scanning direction.
A holder member 55 that integrally holds the supports 39 and 40 and the prism 51 is provided. The holder member 55 is provided with a cylindrical portion 56 at the center of the front surface so as to be positioned on a predetermined support portion so that the optical axis C of the scanning optical system can be pivotally adjusted.
In the above, the method of synthesizing light beams using a plurality of general-purpose semiconductor lasers has been described. However, a method of synthesizing using a plurality of semiconductor laser arrays is also conceivable for further speeding up. Further, a method of combining by using a general-purpose semiconductor laser and a semiconductor laser array in combination is also conceivable.
[0026]
<Third Embodiment>
FIG. 7 is a perspective view showing the configuration of the main part of a multi-beam optical scanning device according to the third embodiment of the present invention. The optical scanning device of this embodiment uses the multi-beam light source device shown in FIG. 6 as the light source device.
7 includes a multi-beam light source device 61, a cylindrical lens 62, a polygon mirror (rotating polygon mirror) 63, an fθ lens 64, a reflection mirror 65, a toroidal lens 66, a photoconductor 67, and a synchronization detection mirror. 68 and a synchronization detector 69. The multi-beam light source device 61 is the multi-beam light source device shown in FIG. 6, and includes support members 39 and 40 on which a semiconductor laser and a collimator lens are mounted, and a holder member 55 having a cylindrical portion 56 projecting therefrom. The fθ lens 64, the reflection mirror 65, and the toroidal lens 66 constitute a scanning imaging optical system.
[0027]
When the four laser light beams emitted from the multi-beam light source device 61 pass through an aperture (aperture aperture) (not shown), the periphery of the light beam is blocked and removed, and the beam is shaped, thereby forming a line image imaging optical system. Is incident on the cylindrical lens 62. The cylindrical lens 62 has a refractive power, that is, a direction without power in the main scanning direction. The cylindrical lens 62 has a positive power in the sub scanning direction, and focuses an incident light beam in the sub scanning direction. The cylindrical lens 62 condenses the light beam emitted from the multi-beam light source device 61 in the vicinity of the deflection reflection surface of the polygon mirror 63 that is an optical deflector. The polygon mirror 63 that reflects the light beam by the deflecting reflection surface is driven to rotate at a constant speed, so that the light beam is deflected at a constant angular speed as the polygon mirror 63 rotates at a constant speed. The light beam deflected along with the constant speed rotation of the polygon mirror 63 passes through the fθ lens 64 and the toroidal lens 66 forming the scanning imaging optical system, and is reflected between the fθ lens 64 and the toroidal lens 66 by the reflection mirror 65. The light is reflected and deflected and condensed on a photoconductive photosensitive member 67 that forms the surface of the scanned surface.
[0028]
The fθ lens 64 and the toroidal lens 66 condense these light beams on the surface of the photoreceptor 67 as four light spots separated in the sub-scanning direction, and simultaneously scan as four scanning lines by these four light spots. To do. Outside the image region in the vicinity of the reflection mirror 65, the light beam to be deflected and scanned is reflected and deflected by the synchronization detection mirror 68 and incident on the synchronization detector 69, which is used for synchronization in the main scanning line direction.
With such an optical scanning device, it is possible to accurately set the scanning line interval on the surface to be scanned with an inexpensive configuration, and to realize optical scanning by a multi-beam method excellent in environmental stability and assemblability. be able to.
[0029]
<Fourth embodiment>
FIG. 8 is a longitudinal sectional view schematically showing a configuration of a main part of a laser printer which is an image forming apparatus according to the fourth embodiment of the present invention. The laser printer of this embodiment uses the optical scanning device shown in FIG. 7, that is, the optical scanning device using the multi-beam light source device of FIG. 6, as the optical scanning device.
That is, the laser printer 100 shown in FIG. 8 includes an image carrier 111, a charging roller 112, a developing device 113, a transfer roller 114, a cleaning device 115, a fixing device 116, an optical scanning device 117, a cassette 118, a registration roller pair 119, a supply roller. A paper roller 120, a conveyance path 121, a discharge roller pair 122, and a tray 123 are provided.
The laser printer 100 has a photoconductive photosensitive member formed in a cylindrical shape as the image carrier 111. Around the image carrier 111, a charging roller 112, a developing device 113, a transfer roller 114, and a cleaning device 115 are provided. Here, the charging roller 112 is used as the charging unit, but a corona charger can also be used as the charging unit. Further, an optical scanning device 117 that performs optical scanning with the laser beams LB1 and LB2 is provided, and the image carrier 111 is exposed by optical writing at an intermediate point between the charging roller 112 and the developing device 113. The cassette 118 stores transfer paper P as a recording medium.
[0030]
When image formation is performed, the image carrier 111, which is a photoconductive photosensitive member, is rotated at a constant speed in the clockwise direction, and the surface of the image carrier 111 is uniformly charged by the charging roller 112. An electrostatic latent image is formed by exposure by optical writing of 117 laser beams LB1 and LB2. The formed electrostatic latent image is a so-called “negative latent image”, and the image portion is exposed. This electrostatic latent image is reversely developed by the developing device 113, and a toner image is formed on the image carrier 111.
The cassette 118 in which the transfer paper P is stored is detachable from the main body of the image forming apparatus 100. In a state where the cassette 118 is mounted as shown in FIG. 8, the uppermost sheet of the stored transfer paper P is taken out by the paper feed roller 120 and fed to the paper feed conveyance system. In the paper feeding / conveying system, the registration roller pair 119 catches the leading end of the fed transfer paper P. Then, the registration roller pair 119 feeds the transfer paper P to the transfer unit at the timing when the toner image on the image carrier 111 moves to the transfer position. The transferred transfer paper P is superimposed on the toner image at the transfer portion, and the toner image is electrostatically transferred onto the transfer paper P by the action of the transfer roller 114.
[0031]
The transfer paper P onto which the toner image has been transferred is sent to the fixing device 116, where the toner image is fixed in the fixing device 116, and is further discharged onto the tray 123 by the paper discharge roller pair 122 through the conveyance path 121. . The surface of the image carrier 111 after the toner image is transferred is cleaned by a cleaning device 115, and residual toner, paper dust, and the like are removed.
In such a laser printer 100, by using the optical scanning device shown in FIG. 7 as the optical scanning device 117, extremely good image formation can be executed.
Therefore, it is possible to accurately set the scanning line interval on the surface to be scanned by an inexpensive method, and it is possible to realize a multi-beam image forming apparatus such as a laser printer excellent in environmental stability and assemblability.
[0032]
【The invention's effect】
  As described above, according to the present invention, reliable and stable image reproducibility is ensured in a multi-beam light source device, an optical scanning device, and an image forming apparatus that constitute a multi-beam light source using a plurality of general-purpose semiconductor lasers. It is possible to provide a multi-beam light source device, an optical scanning device, and an image forming apparatus.
  That is, according to the multi-beam light source device of claim 1 of the present invention, a plurality of light beams emitted from a plurality of light sources are respectively coupled by a plurality of coupling lenses, and then simultaneously using the plurality of light beams. A multi-beam light source device used in an optical scanning device that performs scanning, wherein the plurality of light sources are press-fitted into a plurality of holes arranged in the same support and are detachably held. The coupling lens is bonded to a protruding member projecting from the support, and the protruding member is substantially perpendicular to the direction of the bonding axis for bonding the plurality of coupling lenses, and the lens surface of the coupling lens. Is approximately equal to or greater than the outer diameter of the coupling lens.And the length of the protruding member increases and widens toward the support side.This ensures reliable and stable image reproducibility when configuring a multi-beam light source using multiple general-purpose semiconductor lasers., CheapWith reasonable compositionEasy to assemble,It is possible to accurately set the scanning line interval on the surface to be scanned.In particular, the effect that the scanning line pitch in the sub-scanning direction on the surface to be scanned is hardly affected by the environment even when the environmental temperature varies is obtained..
[0033]
  BookClaims of the invention2According to the multi-beam light source device, the plurality of light sources can include a semiconductor laser array element having a plurality of light-emitting portions, whereby further higher density can be realized.
  Claims of the invention3According to the multi-beam light source device, it is possible to realize further higher density by providing two or more supports and fixing the supports to a common base.
[0034]
  Claims of the invention4According to this optical scanning device, a plurality of light beams emitted from the light source device are elongated in the main scanning direction in the vicinity of the deflection reflection surface position of the optical deflector by the common line image imaging optical system and in the sub scanning direction. A plurality of light beams that are formed as a plurality of separated line images, simultaneously deflected at the same angular velocity by the optical deflector, and the deflected beam is separated on the surface to be scanned in the sub-scanning direction by a common scanning optical system. A multi-beam optical scanning device that condenses light as a spot and simultaneously scans a plurality of scanning lines with the plurality of light spots, and the light source device includes:3By using the multi-beam light source device according to any one of the above, it is possible to accurately set the scanning line interval on the scanned surface of the multi-beam light scanning with an inexpensive configuration, and excellent environmental stability. And assembly can be obtained.
  Claims of the invention5According to this image forming apparatus, the surface to be scanned of a photosensitive image carrier is scanned by an optical scanning unit to form a latent image, and the latent image is visualized by a developing unit to obtain an image. As an optical scanning means for scanning the surface to be scanned of the image carrier,4By using this optical scanning device, it is possible to accurately set the scanning line interval on the scanning surface of the multi-beam optical scanning with an inexpensive configuration, and to obtain excellent environmental stability and assemblability. it can.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view schematically showing a configuration of a main part of a multi-beam light source device according to a first embodiment of the present invention.
2 is a longitudinal sectional view schematically showing the configuration of the multi-beam light source device of FIG. 1. FIG.
3 is a longitudinal sectional view taken along the optical axis schematically showing the configuration of the multi-beam light source device of FIG. 1. FIG.
4 is a perspective view of relevant parts for explaining the configuration of the multi-beam light source device of FIG. 1; FIG.
FIG. 5 is a diagram showing fluctuation characteristics of the scanning line pitch in the sub-scanning direction on the surface to be scanned due to environmental fluctuations for explaining the operation of the multi-beam light source device of FIG. 1;
FIG. 6 is an exploded perspective view schematically showing a configuration of a main part of a multi-beam light source device according to a second embodiment of the present invention.
FIG. 7 is a perspective view schematically showing a configuration of a main part of an optical scanning device according to a third embodiment of the present invention.
FIG. 8 is a longitudinal sectional view schematically showing a configuration of a main part of a laser printer according to a fourth embodiment of the invention.
[Explanation of symbols]
11, 12, 31, 32, 33, 34 Semiconductor laser
13, 14, 35, 36, 37, 38 Collimator lens (coupling lens)
15, 39, 40 Support
16 Mating hole
17, 41, 42 Support protrusion (protrusion member)
18 UV curing adhesive
19, 55 Holder member
20,56 cylindrical part
21 Escape opening
22 Screw holes
23 Screw
51 prism
52 Parallelogram Column
53 Triangular prism
54 1/2 wavelength plate
61 Multi-beam light source device
62 Cylindrical lens
63 Polygon mirror (Rotating polygon mirror)
64 fθ lens
65 Reflective mirror
66 Toroidal Lens
67 photoconductor
68 Mirror for synchronization detection
69 Synchronous detector
100 Laser printer
111 Image carrier
112 Charging roller
113 Developer
114 Transfer roller
115 Cleaning device
116 Fixing device
117 Optical scanning device
118 cassette
119 Registration roller pair
120 Feed roller
121 Transport path
122 Paper discharge roller pair
123 trays
17a, 17b U-shaped support part

Claims (5)

In a multi-beam light source device used for an optical scanning device that scans simultaneously using a plurality of light beams after coupling a plurality of light beams emitted from a plurality of light sources by a plurality of coupling lenses,
A plurality of holes for holding the plurality of light sources in a detachable manner;
A protrusion member that protrudes from the support and attaches the plurality of coupling lenses ;
Shape before Symbol projecting member, the length of a direction substantially parallel to the lens surface of and the coupling lens substantially at right angles to the direction of the adhesive axis for bonding the plurality of coupling lens, the outer diameter of the coupling lens The multi-beam light source device is characterized in that the length of the protruding member increases and expands toward the support side . The multi-beam light source device according to claim 1, wherein the plurality of light sources include a semiconductor laser array element having a plurality of light emitting units. The multi-beam light source device according to claim 1 or 2, wherein two or more supports are provided, and the supports are fixed to a common base. A plurality of light beams emitted from the light source device are combined into a plurality of line images that are long in the main scanning direction and separated in the sub-scanning direction in the vicinity of the position of the deflecting reflection surface of the optical deflector by a common line image forming optical system. Image
Deflected at the same angular velocity simultaneously by the optical deflector,
The deflected beam is condensed as a plurality of light spots separated in the sub-scanning direction on the surface to be scanned by a common scanning optical system,
In a multi-beam type optical scanning device that simultaneously scans a plurality of scanning lines with these plurality of light spots,
As the light source device, an optical scanning apparatus characterized by using a multi-beam light source apparatus according to any one of claims 1 to claim 3. In an image forming apparatus that forms a latent image by scanning a surface to be scanned of a photosensitive image carrier with an optical scanning unit, and visualizes the latent image with a developing unit to obtain an image.
An image forming apparatus using the optical scanning device according to claim 4 as optical scanning means for scanning a surface to be scanned of the image carrier.

Images