JP3103708B2 - Imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an optical printer head or an image reading apparatus such as an image sensor.

[0002]

2. Description of the Related Art A conventional image device, for example, an image device used for an image forming apparatus such as an optical printer head, generally has a light emitting diode element array composed of a plurality of light emitting diode elements formed on an electrically insulating substrate in a linear manner. A plurality of light emitting element mounting substrates are arranged and mounted, a long lens array in which a plurality of bar-shaped self-focusing lenses are linearly arranged in two rows in a frame casing, and a housing made of polycarbonate resin or the like. In the housing, the light emitting element mounting substrate and the lens array are spaced apart from each other at a fixed distance, and each light emitting diode element of the light emitting diode element array is positioned on the optical axis of each self-focusing lens of the lens array. It is manufactured by bonding and fixing with an adhesive such as epoxy resin, or by screwing. .

In such an image apparatus, each light emitting diode element of the light emitting diode element array is selectively and individually made to emit light in accordance with an external electric signal, and the light emitted by each light emitting diode element is externally transmitted via a lens array. By forming an image on the surface of the photoconductor and forming a latent image on the photoconductor, the device functions as an image forming apparatus.

[0004]

However, in this conventional image apparatus, when a light emitting element mounting board having a light emitting diode element array mounted on a housing is fixedly bonded with an adhesive such as an epoxy resin, an adhesive is used. Heat of 150 ° C. has to be applied for about one hour for heat curing, which requires a long time for bonding and fixing, and has the disadvantage of lacking mass productivity. At the same time, since it takes a long time to fix the light emitting element mounting substrate, the position of the light emitting element mounting substrate is likely to shift during adhesive fixing, and if the fixing position of the light emitting element mounting substrate shifts, each self-focusing of the lens array is performed. The disadvantage is that the light emitting diode elements of the light emitting diode element array are not located on the optical axis of the lens, and it is impossible to form a good image of light emitted from each light emitting diode element on an external photoreceptor surface via the lens array. Had also. Furthermore, when the light emitting element mounting board is fixed to the housing by screwing, the housing and the light emitting element mounting board must be provided with screw holes in advance, and the screws must be screwed after matching the screw holes of both. In addition, the workability of fixing the light emitting element mounting substrate is extremely poor, and the image device as a product has a disadvantage of being extremely expensive.

In the above-described conventional example, an image apparatus used for an image forming apparatus such as an optical printer head has been described as an example. However, a solid-state image sensor array (CCD element array) has been described.
An image device used for an image reading device such as an image sensor using the same has the same disadvantage.

[0006]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and has as its object the object of the present invention is to provide a substrate on which an image element array is mounted on a housing having a lens array mounted thereon, and an optical axis of each self-focusing lens of the lens array. It is an object of the present invention to provide a small-sized image device which can be easily and accurately positioned and fixed in a short time so that each image element of an image element array is positioned thereon.

[0007]

According to an image apparatus of the present invention, an upper surface of a substrate on which an image element array is mounted is placed on a reference surface in a housing having a lens array mounted thereon.
An image device contacted on both sides of an image element array mounting portion, wherein the lower surface of the substrate is provided on a metal plate locked to a housing at a position corresponding to the reference surface on both sides of the image element array mounting portion. And pressing the substrate by the plurality of convex portions, and pressing the upper surface of the substrate to a reference surface of the housing with the pressing force to hold the substrate.

[0008]

According to the image device of the present invention, the upper surface of the substrate on which the image element array is mounted abuts on the reference surface of the housing on both sides of the image element array mounting portion, and the lower surface is formed on both sides of the image element array mounting portion. At a position corresponding to the reference surface, since it is configured to be pressed by a plurality of protrusions provided on the metal plate locked to the housing, the upper surface of the substrate is brought into contact with the reference surface of the housing by the pressing force of the protrusions. The image element array mounting portion of the substrate can be held in a flat state. Thereby, the image element array can be accurately positioned on the optical axis of each self-focusing lens of the lens array, and when such an image device is used in an image forming apparatus such as an optical printer head, the light emitting diode element The emitted light is radiated favorably on the photoreceptor via the lens array, and a clear and accurate latent image can be formed on the photoreceptor, and the image device is used for an image reading device such as an image sensor. In this case, the external image information can be accurately formed on the solid-state imaging device array via the lens array, and the solid-state imaging device array can generate an accurate electric signal corresponding to the external image information. .

Further, according to the image apparatus of the present invention, only a metal plate having a relatively small projection is disposed below the substrate, and the metal plate is fixed to the housing by simply holding the metal plate on the housing. Since it is possible to satisfactorily press against the reference plane, it is not necessary to secure a large space for accommodating a large pressing means or the like below the substrate, and it is possible to provide a downsized image device.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the accompanying drawings. 1 and 2 show an embodiment in which the image apparatus of the present invention is applied to an optical printer head as an image forming apparatus, wherein 1 is a substrate, 2 is a light emitting diode element array (image element array), and 3 is a lens. The array, 4 is a housing.

The substrate 1 is made of an electrically insulating material such as ceramic, glass, glass epoxy or the like. A plurality of light emitting diode element arrays 2 are linearly arranged and mounted on the upper surface thereof.

The substrate 1 functions as a support member for supporting the light emitting diode element array 2. For example, when the substrate 1 is made of a ceramic of an aluminum oxide sintered body, alumina (Al ₂ O ₃ ), silica (SiO ₂ ) ₂ ), Calcia (C
aO), magnesia (MgO), etc., a suitable organic solvent and a solvent are added and mixed into a slurry to form a slurry, and the ceramic green sheet (aO) or magnesia (MgO) is formed by employing a conventionally known doctor blade method or calendar roll method. A ceramic green sheet is obtained, and thereafter, the ceramic green sheet is punched into a predetermined shape and fired at a high temperature (about 1600 ° C.).

The light emitting diode element array 2 mounted on the substrate 1 has a plurality of light emitting diode elements 2a.
The light emitting diode elements 2a individually and selectively emit light in response to an external electric signal, and form a predetermined latent image on the photoconductor 5 by irradiating the emitted light to the surface of the photoconductor 5.

The light emitting diode element 2a is G
aAsP-based and GaP-based light-emitting diodes are used. For example, in the case of a GaAsP-based light-emitting diode, first, a GaAs substrate is heated to a high temperature in a furnace, and As
A gas containing an appropriate amount of H ₃ (arsine), PH ₃ (phosphine), and Ga (gallium) is brought into contact with the substrate to grow a single crystal of GaAsP (gallium-arsenic-phosphorus) as an n-type semiconductor on the surface of the substrate. A window film of Si ₃ N ₄ (silicon nitride) is deposited on the surface of the single crystal, and Zn
(Zinc) gas is exposed, Zn is diffused into a part of the n-type semiconductor GaAsP single crystal to form a p-type semiconductor, and pn
It is formed by having a bond.

In the case of a B4 size optical printer head, 2048 (8 per mm) light emitting diode elements 2a are linearly arranged. Specifically, 64 light emitting diodes are used as one unit. Light emitting diode array
By arranging 32 light emitting diode elements 2 in a linear manner, 2048 light emitting diode elements 2a are arranged on the base plate 1.

Further, a lens array 3 is arranged above the light emitting diode elements 2a at a predetermined distance, and the lens array 3 irradiates the light emitted from each light emitting diode element 2a to the surface of the photosensitive member 5. Make

The lens array 3 has a structure in which a plurality of rod-shaped self-focusing lenses 7 made of glass, synthetic resin, or the like are linearly arranged in two rows in a frame-shaped casing 6. The rod-shaped self-focusing lens 7 is sandwiched in two rows between ABS resin or FRP plates, and a silicone resin is dropped between the ABS resin or FRP plate and each self-focusing lens 7, and the resin is cured to form a frame. The self-focusing lens 7 is manufactured by bonding the self-shaped casing 6 and the self-focusing lens 7 with a silicone resin.

The substrate 1 on which the light emitting diode element array 2 is mounted and the lens array 3 have a certain distance between them, and the optical axis of each self-focusing lens 7 of the lens array 3 is It is fixed to a housing 4 made of resin so as to be on each of the light emitting diode elements 2a.

The fixing of the lens array 3 to the housing 4 is performed by bonding and fixing the lens array 3 to the upper portion of the housing 4 via an adhesive made of epoxy resin.

In order to fix the substrate 1 on which the light emitting diode element array 2 is mounted to the housing 4, a reference surface 4a is provided below the housing 4, and the light emitting diode element array 2 is mounted on the reference surface 4a. The upper surface of the substrate 1 is brought into contact with both sides of the light-emitting diode element array mounting portion, and the lower surface of the substrate 1 is positioned at a position corresponding to the reference surface 4a on both sides of the light-emitting diode element array mounting portion.
Pressing with a plurality of projections 8a provided on the metal plate 8 locked to 4,
With the pressing force, the upper surface of the substrate 1 is moved to the reference surface 4a of the housing 4.
This is performed by holding the substrate 1 in contact with the substrate. In this case, the substrate 1 on which the light emitting diode element array 2 is mounted is brought into contact with the reference surface 4a of the housing 4 so that each light emitting diode element 2a of the light emitting diode element array 2 is illuminated by each self-focusing lens 7 of the lens array 3. The light emitted from each light emitting diode element 2a can be accurately positioned on the axis,
By irradiating the photosensitive member 5 satisfactorily through 3, a clear and accurate latent image can be formed on the photosensitive member 5. At the same time, the metal plate 8 provided with the plurality of protrusions 8a has an uneven surface, and the overall mechanical strength is strong, and the flatness in the direction along the unevenness is maintained high.
1 can be pressed against the reference surface 4a of the housing 4 with a uniform pressure, whereby the substrate 1 on which the light emitting diode elements are mounted is more accurately held at a predetermined position of the housing 4 and each light emitting diode element 2a emits light. Light into a lens array
By irradiating the photosensitive member 5 satisfactorily through 3, a clear and accurate latent image can be formed on the photosensitive member 5. Moreover, in this case, a relatively small projection 8a is provided below the substrate 1.
Only the metal plate 8 having the metal plate 8 is disposed, and since the substrate 1 can be satisfactorily pressed against the reference surface 4a of the housing 4 only by locking the metal plate 8 to the housing 4, It is not necessary to secure a wide space for accommodating a large pressing means or the like, and it is possible to provide a downsized image apparatus.

The metal plate 8 having a plurality of projections 8a to be locked to the housing 4 is made of a metal material such as aluminum, for example.
It is formed by performing conventionally well-known metal working such as bending.

The locking of the metal plate 8 to the housing 4 can be performed, for example, by locking the lower locking pin 4b of the housing 4 to the metal plate 8.
As shown in FIG. 2, a locking hole 9 having a region 9a having a diameter larger than the diameter of the locking pin 4b and a region 9b having a diameter smaller than the diameter of the locking pin 4b is provided, and the locking pin 4b is provided. This is performed by inserting the locking hole 9 from the large-diameter region 9a and moving to the small-diameter region 9b, and locking the locking pin 4b into the locking hole 9. In this case, the board 1 on which the light-emitting diode element array 2 is mounted can be fixed at a predetermined position of the housing 4 simply by locking the locking hole 9 of the metal plate 8 with the locking pin 4b provided on the housing 4. The substrate 1 on which the element array 2 is mounted can be easily and accurately fixed to the housing 4 in a short time, and the workability of manufacturing an image device is extremely excellent, making the image device as a product inexpensive. You can also.

Further, in the embodiment shown in FIG. 1, the metal plate 8 is disposed only on the lower surface of the housing 4, which is shown in FIGS. 3 (a) and 3 (b).
As shown in FIG. 7, the housing 4 may extend to one side or both sides. In particular, a driving IC for selectively and selectively emitting light from each light emitting diode element 2a of the light emitting diode element array 2 is mounted on a substrate 1 on which the light emitting diode element array 2 is mounted, and an electrophotographic type. When a charger or the like is provided near the side surface of the housing 4 when used in a printer or the like, static electricity or high-voltage discharge noise may act on the driving IC, causing damage to the driving IC. However, if the metal plate 8 is extended on the side surface of the housing 4 on the side where the charger and the like are arranged, the metal plate 8
, The driving IC is effectively prevented from being destroyed. Therefore, for example, when a charger or the like that generates static electricity or high-voltage noise is provided on the side surface of the housing 4, the metal plate 8 is provided on the side surface on which the charger or the like is provided. Preferably, 8 is extended.

Thus, according to the image apparatus of the present invention, the substrate 1
A plurality of light emitting diode elements 2a linearly arranged on
To selectively emit light individually in response to an external electric signal,
By irradiating the emitted light to the photoreceptor 5 via the lens array 3, the device functions as an image forming apparatus.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.
Although 4b is provided in the housing 4 and the locking hole 9 is provided in the metal plate 8, the reverse may be adopted, and the locking hole 9 is provided in the housing 4 and the locking pin 4b is provided in the metal plate 8.

In the above embodiment, the case where the present invention is applied to an image forming apparatus such as an optical printer head has been described.
The light emitting diode element array can be used for an image reading device such as an image sensor instead of a solid-state imaging element array.

[0027]

According to the image device of the present invention, according to the image device of the present invention, the upper surface of the substrate on which the image element array is mounted is brought into contact with the reference surface of the housing on both sides of the image element array mounting portion. The lower surface is pressed by a plurality of convex portions provided on a metal plate locked to the housing at positions corresponding to the reference surfaces on both sides of the image element array mounting portion. The pressing force of the portion satisfactorily abuts the reference surface of the housing, and the image element array mounting portion of the substrate can be held in a flat state. Thereby, the image element array can be accurately positioned on the optical axis of each self-focusing lens of the lens array, and when such an image device is used in an image forming apparatus such as an optical printer head, the light emitting diode element The emitted light is radiated favorably on the photoreceptor via the lens array, and a clear and accurate latent image can be formed on the photoreceptor, and the image device is used for an image reading device such as an image sensor. In this case, the external image information can be accurately formed on the solid-state imaging device array via the lens array, and the solid-state imaging device array can generate an accurate electric signal corresponding to the external image information. .

Further, according to the image apparatus of the present invention, only the metal plate having a relatively small convex portion is disposed below the substrate, and the metal plate is fixed to the housing only by holding the metal plate on the housing. Since it is possible to satisfactorily press against the reference plane, it is not necessary to secure a large space for accommodating a large pressing means or the like below the substrate, and it is possible to provide a downsized image device.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment in which an image forming apparatus according to the present invention is applied to an optical printer head as an image forming apparatus.

FIG. 2 is a partially enlarged plan view for explaining engagement between a metal plate and a housing used in the optical printer head shown in FIG. 1;

FIGS. 3A and 3B are cross-sectional views showing another embodiment of the present invention.

[Explanation of symbols]

1 ... substrate, 2 ... light emitting diode array (image element array), 2a ... light emitting diode, 3 ... lens array, 4 ... housing, 4a ... reference plane, 4b ...
・ Locking pin, 6 ・ ・ ・ Frame-shaped casing, 7 ・ ・ ・ Bar-shaped lens, 8 ・ ・ ・ Metal plate, 8a ・ ・ ・ Locking hole

Claims (1)

(57) [Claims] An image device comprising an image element array mounted on both sides of a substrate on which an image element array is mounted, on a reference surface in a housing having a lens array mounted thereon. The lower surface of the substrate is attached to the substrate on both sides of the image element array mounting portion.
In a position corresponding to the reference plane, and pressed by a plurality of protrusions provided on the metal plate to be locked in the housing, the upper surface of the substrate with a pressing pressure brought into contact with the reference surface of the housing for holding a substrate An imaging device characterized by doing so .