JP3184566B2 - Light receiving or light emitting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light receiving device of a horizontal synchronizing signal detecting unit used in a scanning optical device for recording an image by scanning a recording medium with a laser beam modulated by an image signal, or an optical signal. The present invention relates to a light emitting device in a laser beam emitting device that emits light.

[0002]

2. Description of the Related Art In recent years, recording apparatuses such as laser beam printers for recording an image by scanning a laser beam have been widely used. In this recording apparatus, a photosensitive member as a recording medium is scanned by a light beam deflected and scanned by an optical deflector, and an electrostatic latent image is formed. The electrostatic latent image is visualized as a toner image by a developing device, the toner image is transferred to a recording sheet, and after the transfer of the toner image, the toner is heated and fixed to the recording sheet by a fixing device. Is performed.

A laser scanning device used in a conventional image recording apparatus will be described below with reference to FIG.

In FIG. 7, reference numeral 100 denotes an optical housing of a scanning optical device. Reference numeral 101 denotes a semiconductor laser unit including a semiconductor laser, a collimator lens system, and the like. Reference numeral 102 denotes a cylindrical lens that linearly condenses a light beam generated from the semiconductor laser unit 101. Reference numeral 103 denotes an optical deflector having a deflecting / reflecting surface near a line image of the light beam condensed by the cylindrical lens 102. Is a polygon mirror, 1
Reference numerals 04a and 104b denote imaging optical systems (fθ lens systems), 10
Reference numeral 5 denotes a reflection mirror unit for guiding a horizontal synchronization signal to a light receiving sensor. Reference numeral 106 denotes an optical slit that determines a horizontal synchronization signal integrated with the optical housing, and 107 denotes a condenser lens that receives an optical signal. Reference numeral 108 denotes a sensor that receives a light receiving signal. The sensor 108 outputs a horizontal synchronization signal for detecting the scanned position of the light beam when the light receiving surface is irradiated with the light beam deflected and scanned by the polygon mirror 103. Reference numeral 115 denotes a photoconductor as a recording medium.

[0005] The rotation of the polygon mirror 103 causes main scanning of the photosensitive member 115 with a light beam, and the sub-scanning is performed by rotating the photosensitive member 115 about the axis of the cylinder. Thus, an electrostatic latent image is formed on the surface of the photoconductor 115.

A corona discharger for uniformly charging the surface of the photoconductor 115, a photoconductor 11
A developing device for visualizing the electrostatic latent image formed on the surface of No. 5 into a toner image, a transfer corona discharger (both not shown) for transferring the toner image to recording paper, and the like. , The semiconductor laser unit 101
The recording information corresponding to the luminous flux in which is generated is printed on the recording paper.

Reference numeral 109 denotes an electric circuit board on which the light receiving sensor 108 is mounted. 110a, 110b, 11
0c, 110d are connection terminal connectors, 111a, 11
1b is a connection cable, and each of the light receiving sensors 10b
The signal detected in step 8 is transmitted to a control circuit or a drive signal is transmitted to the semiconductor laser unit 101. 11
Reference numeral 2 denotes a control circuit device of the scanning optical device, which controls the rotation of the polygon mirror 103 and the emission control of the semiconductor laser unit, in addition to the processing of the horizontal synchronization signal.

Reference numeral 113 denotes an electric circuit board of a motor for rotating the polygon mirror 103, which is connected to the control circuit device 112 via a line. Reference numeral 114 denotes an electric circuit board on which the semiconductor laser in the semiconductor laser unit 101 is mounted.

[0009]

However, the apparatus shown in FIG. 7 has the following problems. (1) There are the following problems regarding the assemblability of parts. That is, the electric board 109 of the light receiving sensor 108,
Alternatively, an electric circuit board 114 on which a semiconductor laser is mounted
Must be assembled from the side of the optical housing 100 (in the direction parallel to the paper surface in FIG. 7). Therefore, it is difficult to automatically assemble the connector due to insertion of a connector and clamping of an electric bundle. Was. (2) Further, the position of the light receiving sensor 108 or the semiconductor laser attached to the electric circuit board changes due to the deformation of the electric circuit board when the connector is attached or detached, and as a result, the position of the input light or the output light. , There is a problem that the optical signal becomes unstable. (3) Since the connection between the light receiving sensor 108 or the semiconductor laser element and the control circuit is made via a connector and a connection cable on the electric circuit board, there is a problem due to poor contact of the connector. (4) When the length of the light receiving sensor 108 or the connection cable between the semiconductor laser and the control circuit is long, there has been a problem that the signal responsiveness is reduced or external electric noise is taken in. (5) The positioning of the optical axis of the light receiving sensor 108 and the condensing lens 107 is fixed to the optical housing via the positioning hole on the electric board, which is difficult to obtain dimensional accuracy.
There was a problem that the input signal became unstable. (6) The electric circuit board 109 of the light receiving sensor 108 or the electric circuit board 114 of the semiconductor laser element is perpendicular to the motor circuit board 113 of the deflector, and forms the same control circuit board and is common to the electric circuit board. This has hindered the realization of cost reduction and improvement in assemblability due to the development.

[0010]

In order to achieve the above object, a light receiving device according to the present invention comprises: a light receiving element for receiving an optical signal; an electric circuit board comprising a flexible substrate on which the light receiving element is mounted; A condensing lens for guiding an optical signal to the element is mounted on the same holding member, and the flexible substrate is bent and fixed by a guide portion of the holding member to form one light receiving device.

In order to achieve the above object, in a light emitting device according to the present invention, a light emitting element for emitting an optical signal, an electric circuit board comprising a flexible substrate on which the light emitting element is mounted, and light from the light emitting element are parallelized. A collimator lens for forming a light beam is mounted on the same holding member, and the flexible substrate is bent and fixed by a guide portion of the holding member to form one light emitting device.

Thus, one light receiving element unit,
By using a single light emitting element unit, automatic assembly can be performed, and improvement in assemblability, reduction in cost, and improvement in reliability of optical signal input (output) can be realized.

[0013]

FIG. 1 is a plan view illustrating the configuration of an embodiment of a scanning optical device using a light receiving device and a light emitting device according to the present invention.

In FIG. 1, reference numeral 100 denotes an optical housing of a scanning optical device. Reference numeral 201 denotes a semiconductor laser unit (light emitting device) including a semiconductor laser, a collimator lens system, and the like. Reference numeral 102 denotes a cylindrical lens for condensing a light beam generated from the semiconductor laser unit 201 into a linear shape, and 103 denotes the cylindrical lens 10.
A polygon mirror 104, which is an optical deflector having a deflecting / reflecting surface in the vicinity of a line image of a light beam condensed by the light beam 2;
Reference numerals a and 104b denote an imaging optical system (fθ lens system), and 105 denotes a reflection mirror unit for guiding a horizontal synchronization signal to a light receiving sensor. Reference numeral 202 denotes a light receiving device including an optical slit, a condenser lens, a sensor for receiving an optical signal, and the like. The light receiving surface of the sensor of the light receiving device 202 has a polygon mirror 10
When irradiated with the light beam deflected and scanned by 3, a horizontal synchronization signal for detecting the scanned position of the light beam is output. Reference numeral 115 denotes a photoconductor as a recording medium. The rotation of the polygon mirror 103 causes the photoconductor 11 to rotate.
In 5, the main scanning is performed by the light beam, and the sub-scanning is performed by rotating the photoconductor 115 around the axis of the cylinder. Thus, an electrostatic latent image is formed on the surface of the photoconductor 115.

Around the photosensitive member 115, a corona discharger for uniformly charging the surface of the photosensitive member 115,
A developing device for visualizing the electrostatic latent image formed on the surface of No. 5 into a toner image, a transfer corona discharger (both not shown) for transferring the toner image to recording paper, and the like. , The semiconductor laser unit 201
The recording information corresponding to the luminous flux in which is generated is printed on the recording paper.

Reference numeral 203 denotes a control circuit board of the scanning optical device, which controls the rotation of the polygon mirror 103 and the light emission of the semiconductor laser unit 201, in addition to the processing of the horizontal synchronization signal obtained by the light receiving device 202.

FIG. 2 shows a light receiving device 202 used in FIG.
FIG. 3 is a diagram illustrating the configuration of FIG. In FIG. 2, 1 is a holding member of a light receiving unit, 2 is a light receiving lens of an optical signal, 3 is a light receiving sensor, 4 is a flexible circuit board, 203 is an electric circuit board for mounting a light receiving device, and 6 is an electric circuit board 20
An optical signal processing control IC mounted on 3 and an optical signal amplifier 7 mounted on the flexible substrate 4 are shown.

In such a schematic configuration, the holding member 1 is formed by a resin molded member, and the light receiving lens 2 and the light receiving sensor 3 are pressed into a predetermined position of the holding member 1 or snap fit. Or, it is fixed by bonding. After the light receiving lens 2 and the light receiving sensor 3 are fixed to the holding member 1, the flexible substrate 4 and the light receiving sensor 3 are connected by soldering.
The holding member 1 is provided with an optical slit portion 8 near the light receiving lens 2. Of course, an optical opening may be used instead of the optical slit portion.

Further, the flexible substrate 4 includes the holding member 1.
From the flexible board fixing guide portion 1-c. The flexible substrate 4 is fixed to the holding member 1 by applying a double-sided adhesive tape or an adhesive to a surface where the flexible substrate 4 and the holding member 1 are in contact with each other. The flexible substrate 4 is a single-sided through-hole substrate, and the solder surface and the surface of the pattern 4-c are on the 4-d side (the back surface of the substrate). Therefore, the guide portion 1 of the holding member 1
By bending at −c, the pattern surface 4-c of the connection terminal portion of the flexible substrate becomes the electric circuit pattern and the solder surface 5-e of the electric circuit board 203 on which the light receiving device is mounted.
Side.

The light receiving device 202 is positioned and fixed by fitting the positioning fixing pins 1-a and 1-b of the holding member 1 into the fixing holes 5-a and 5-b on the electric circuit board 203. You. Thereafter, the positioning fixing pins 1-a and 1-b of the holding member 1 are melted and fixed from the back side of the electric circuit board 203 by thermal welding. Alternatively, adhesive fixing or screw fixing may be used. The electrical connection terminals 5-e of the electric circuit board 203 are on the reference surface side of the attachment of the holding member 1 to the electric circuit board 203.

The fixing between the flexible substrate 4 and the electric circuit board 203 is performed as shown in FIG. 1
Reference numeral 0 denotes a soldering iron, and positioning reference pins 1-a, 1-
b, 10-a and 10-b are fixed by soldering by fitting into positioning holes 4-a and 4-b of flexible substrate 4 and positioning holes 5-c and 5-d on the electric circuit board. . As the solder, a paste-like low melting point cream solder is used. As described above, if the optical signal amplifier 7 is mounted immediately after the light receiving sensor 3 on the flexible substrate 4, signal attenuation and electric noise superposition can be prevented, and the performance is stabilized.

FIG. 4 shows a light emitting device 201 used in FIG.
FIG. 3 is a diagram illustrating the configuration of FIG. In FIG. 4, reference numeral 31 denotes a semiconductor laser which is a light emitting element; 32, a collimator lens for converting light from the semiconductor laser 31 into a parallel light beam;
33 is a lens barrel holding the collimator lens 32;
Reference numeral 1 denotes a holding member that holds the lens barrel 33 and the flexible substrate 44. Reference numeral 41-2 denotes a base for holding the semiconductor laser 31, and after adjusting the optical axis and the focus of the semiconductor laser 31 and the collimator lens 32, the fixing screw 34a,
34b, it is fixed to the holding member 41-1. 4
Reference numeral 6 denotes a control IC for optical signal processing mounted on the electric circuit board 203.

In such a schematic configuration, the holding member 41
-1 is formed by a resin molding member,
The lens barrel 33 and the semiconductor laser 31 are held by a holding member 41-1.
Is fixed by press-fitting, snap-fitting, or bonding. Thus, the holding member 4
After the lens barrel 33 and the semiconductor laser 31 are fixed to 1-1, the flexible substrate 44 and the semiconductor laser 31 are connected by soldering. The holding member 41-1 is provided with an optical slit portion near the collimator lens 32. Of course, an optical opening may be used instead of the optical slit portion.

The flexible substrate 44 is bent from the flexible substrate bending surface 41-1c of the holding member 41-1. Holding member 41-1 of flexible substrate 44
Is fixed to the flexible substrate 44 and the holding member 41.
-1 is fixed by applying a double-sided pressure-sensitive adhesive tape or an adhesive to the surface to be contacted. Flexible board 44
Is a single-sided through-hole substrate, and the solder surface and the surface of the pattern 44-c are on the 44-d side. Therefore, by bending at the bent surface 41-1c of the holding member 41-1, the pattern surface 44-c of the connection terminal portion of the flexible substrate 44 becomes the electric circuit board 2 on which the light emitting device 201 is mounted.
The electrical circuit pattern 03 and the solder surface 45-e side. The electric connection terminals 45-e of the electric circuit board 203 are:
The holding member 41-1 is on the reference side for attachment to the electric circuit board 203.

The positioning and fixing of the light emitting device 201 is performed by positioning and fixing pins 41-1a and 41-1b of the holding member 41-1.
Are fixed holes 45-a and 45-b on the electric circuit board 203.
It is positioned by fitting into. After that, the positioning fixing pins 41-1a, 41-1b of the holding member 41-1.
Are fixed by melting from the back side of the electric circuit board 203 by thermal welding. Alternatively, adhesive fixing or screw fixing may be used.

FIG. 5 shows a light receiving device according to another embodiment of the present invention. Members having the same functions as those of the embodiment shown in FIG. 2 are denoted by the same reference numerals. The flexible substrate 4 includes the holding member 1
Is bent to approximately 90 degrees by the bending guide portion 1-c. The fixing of the flexible substrate 4 to the holding member 1
The flexible substrate 4 and the holding member 1 are fixed by applying a double-sided adhesive tape or an adhesive to a surface 1-d where the holding member 1 contacts. Further, the holding member 1 and the flexible substrate 4
Is fixed to a base 47.

FIG. 6 shows a light receiving device according to another embodiment of the present invention. Members having the same functions as those of the embodiment shown in FIG. 2 are denoted by the same reference numerals. The terminal of the light receiving element 3 is a surface mount type, and the solder surface (pattern surface) of the flexible substrate 4 is used.
Is on the 4-d side. The connection method with the electric control circuit board 203 is the same as that of the embodiment shown in FIG.

[0028]

As described above, according to the present invention, the following effects can be obtained by unitizing a light receiving (or light emitting) element with a flexible electric circuit board. (1) The positioning of the light receiving (or light emitting) element and the optical lens can be assembled and adjusted in a unit state, and the productivity is excellent. (2) Since there is no need for an electrical connector, no mechanical stress is applied at the time of attachment and detachment, so that optical axis and defocus due to deformation can be avoided. In addition, the cost is reduced. (3) A control IC, an amplifier, or the like can be mounted near the light receiving (or light emitting) element, thereby improving the reliability of the device. In addition, high-density mounting becomes possible, which contributes to downsizing of the device.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a scanning optical device using a light receiving device and a light emitting device of the present invention.

FIG. 2 is a diagram illustrating a configuration of a light receiving device used in FIG.

FIG. 3 is a diagram illustrating fixing of a flexible board and an electric circuit board.

FIG. 4 is a diagram illustrating a configuration of a light emitting device used in FIG.

FIG. 5 is a diagram illustrating a configuration of another embodiment of the light receiving device.

FIG. 6 is a diagram illustrating a configuration of another embodiment of the light receiving device.

FIG. 7 is a diagram illustrating a conventional laser scanning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holding member 2 Light receiving lens 3 Light receiving sensor 4 Flexible board 203 Electric circuit board

Continued on the front page (58) Investigated field (Int.Cl. ⁷ , DB name) B41J 2/44 G02B 26/10 H01S 5/022 G03G 15/04

Claims (12)

(57) [Claims] 1. A light receiving element for receiving an optical signal, an electric circuit board comprising a flexible substrate on which the light receiving element is mounted, a light receiving lens for guiding an optical signal to the light receiving element, and a holder for mounting the light receiving element and the light receiving lens. A light receiving device comprising a member, wherein the flexible substrate is bent and fixed to a guide portion of the holding member, and a part of a circuit pattern portion of the flexible substrate can be electrically connected to another electric circuit substrate. A light receiving device, wherein the holding member has a means for positioning the other electric circuit board. 2. The light receiving device according to claim 1, wherein the holding member is formed of a resin mold member, and the other electric circuit board is thermally welded, adhered, or screwed to the holding member. 3. The light-receiving device according to claim 1, wherein the electrical connection terminal portion of the another electric circuit board is on a mounting reference surface side of the holding member. 4. The light receiving device according to claim 1, wherein the light receiving element is positioned and fixed by fitting, press-fitting, or snap-fitting the holding member. 5. The light receiving device according to claim 1, wherein an optical slit portion is provided on the holding member. 6. The light receiving device according to claim 1, wherein an optical opening is provided in the holding member. 7. A light emitting element that emits an optical signal, an electric circuit board including a flexible substrate on which the light emitting element is mounted, a collimator lens that converts the optical signal into a parallel light beam, and the light emitting element and the collimator lens are mounted. The flexible substrate is bent along the holding member and fixed to the bottom surface of the holding member, and a portion of the flexible substrate fixed to the bottom surface of the holding member. A light emitting device, wherein a circuit pattern portion on a lower surface of the light emitting device is electrically connectable to another electric circuit board, and the holding member is provided with means for positioning with the other electric circuit board. . 8. The light emitting device according to claim 7, wherein the holding member is formed of a resin mold member, and the other electric circuit board is heat-welded, bonded, or screw-fixed to the holding member. 9. The light emitting device according to claim 7, wherein an electrical connection terminal portion of the another electric circuit board is on a mounting reference surface side of the holding member. 10. The light emitting device according to claim 7, wherein the light emitting element is positioned and fixed by fitting, press-fitting, or snap-fitting the holding member. 11. The light emitting device according to claim 7, wherein an optical slit portion is provided on the holding member. 12. The light emitting device according to claim 7, wherein an optical opening is provided in the holding member.