JP2851776B2 - 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 apparatus, for example, an image apparatus used for an image forming apparatus such as an optical printer head, is usually a lens made of a resin such as polycarbonate in which a plurality of lenses are linearly supported at predetermined intervals. A plate and a base plate made of a resin such as polycarbonate, in which a large number of light emitting diode element arrays are linearly arranged and mounted, have a one-to-one correspondence between each lens and each light emitting diode element array via a pair of supports. As described above, the light emitting diode elements of each light emitting diode element array are selectively and individually lit according to an external electric signal, and the light emitted by the light emitting diode elements is transmitted to a lens. An image is formed on the surface of an external photoconductor via the photoconductor, and a latent image is formed on the photoconductor to function as an image forming apparatus.

A light emitting diode element array linearly arranged and mounted on the base plate generally includes 64 light emitting diode elements linearly arranged therein, and is used in a B4 size image forming apparatus. When used, the light emitting diode element array is mounted on the base plate such that 32 light emitting diode elements correspond to the respective lenses one by one.

In addition, each of the light emitting diode elements on the base plate has a common electrode and an individual electrode formed on a common electrode wiring and an individual electrode wiring which are previously formed on the upper surface of the base plate, and a common electrode is formed directly through a metal brazing material. The individual electrodes are electrically connected to the common electrode wiring and the individual electrode wirings via bonding wires, respectively. Each light emitting diode element is connected by connecting the common electrode wiring and the individual electrode wiring on the upper surface of the base plate to an external electric circuit. Are electrically connected to an external electric circuit.

Further, when a shift occurs between the positions of the respective lenses supported by the lens plate and the respective light emitting diode element arrays mounted on the base plate, the image formed on the photoreceptor surface becomes blurred, white stripes or black stripes. Since it is impossible to form a clear and accurate latent image due to the occurrence of the above, it is necessary to align each lens and each light emitting diode element array with extremely high precision.

[0006]

However, in this conventional image device, the individual electrodes of each light emitting diode element are connected to the individual electrode wiring of the base plate via a bonding wire, and the individual electrodes of each light emitting diode element are Due to the large number of thousands, it takes a long time to electrically connect the individual electrodes of each light-emitting diode element to the individual electrode wiring of the base plate, and the workability of manufacturing image devices is poor. Had the disadvantage of

In a conventional image apparatus, a lens plate for supporting a plurality of lenses on a pair of supports and a base plate on which a large number of light emitting diode element arrays are mounted are individually fixed to each other and each lens and each light emitting diode. When the base plate is fixed to the support, when the base plate is fixed to the support, if the fixing position of the base plate shifts, light emitted from each light emitting diode element of the light emitting diode element array is passed through the lens to the photosensitive member surface. The image formed on the surface of the photoreceptor is blurred, resulting in blurs, white streaks, and black streaks, which makes it impossible to form a clear and accurate latent image. Had also.

Further, in the above-mentioned 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.
Also in an image device used for an image reading device such as an image sensor using the image sensor, the image formation of the external image information on the solid-state image sensor array becomes non-uniform due to a positional shift between the lens and the solid-state image sensor array, There is a disadvantage that it is impossible to generate an accurate electric signal corresponding to the image information in the solid-state imaging device array.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and has as its object to accurately irradiate light emitted from a light-emitting diode element onto a photoreceptor surface via a lens, and to provide a latent image with high image quality on the photoreceptor Or the ability to accurately form external image information on a solid-state image sensor array via a lens, and to generate an accurate electric signal corresponding to the external image information on the solid-state image sensor array. To provide a good image device.

[0010]

The present invention comprises a lens plate in which a plurality of lenses are linearly arranged at predetermined intervals and supported, and a base plate in which a large number of image element arrays are linearly arranged and mounted. An image device in which a lens plate and a base plate are fixedly provided side by side via a support so that each lens and each image element array correspond one-to-one, wherein the image element array is mounted on the base plate by face-down bonding. And, while providing two projections having a positioning reference surface on the support, and holding the base plate and the elastic body between the two projections,
The elastic member presses the base plate against the positioning reference surface of the projection.

[0011]

According to the image apparatus of the present invention, the individual electrodes of each image element are electrically connected by face-down bonding to the individual electrode wiring previously formed on the surface of the base plate. Even if there are thousands, all of them are electrically connected to the individual electrode wirings of the base plate at once and firmly, and as a result, the productivity and reliability of the image apparatus become extremely excellent.

Further, according to the image apparatus of the present invention, two projections having a positioning reference surface are provided on the support, and the base plate and the elastic body are sandwiched between the two projections. Since the base plate on which a large number of image element arrays are mounted can be fixed to the support by simple work because it is pressed against the surface, and the large number of image element arrays mounted on the base plate are accurately fixed at predetermined positions, Each image element array can be accurately opposed to each lens supported by the lens plate. Therefore, when this image apparatus is used in an image forming apparatus such as an optical printer head, the center of each lens is always located at the center of the light emitting diode element array, and the light emitted from the light emitting diode elements of each light emitting diode element array Irradiates the entire surface of the photosensitive member satisfactorily, and a clear and accurate latent image can be formed on the photosensitive member. At the same time, when this image device is used in an image reading device such as an image sensor, since each lens and each image element array always face accurately, external image information is transferred to the solid-state image sensor array via the lens. An image can be accurately formed on the entire surface, and an accurate electric signal corresponding to external image information can be generated in the solid-state imaging device array.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to 3 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 base plate, 5 is a lens plate, and 7 is a support.

The base plate 1 is made of, for example, glass epoxy resin or the like, and a plurality of light emitting diode element arrays 3 are linearly arranged and mounted on the lower surface thereof.

The base plate 1 functions as a support member for supporting the light emitting diode element array 3 and connects the individual electrodes 31 provided on the light emitting diode element array 3 to an external electric circuit, as shown in FIG. The individual electrodes 31 provided on each light emitting diode element array 3 are connected by face down bonding to the individual electrode wirings 1a previously attached to the lower surface of the base plate 1, and specifically, the base plate 1 is attached to the upper surface of each light emitting diode element array 3.
To the individual electrodes 31 provided on the light emitting diode element array 3.
And the individual electrode wirings 1a attached to the lower surface of the base plate 1 are placed so as to face each other with the solder bumps 4 interposed therebetween, and then the solder bumps 4 are heated and melted, and the light emitting diode element arrays 3 The individual electrodes 31 provided on each light emitting diode element array 3 are formed by soldering the provided individual electrodes 31 and the individual electrode wirings 1a of the base plate 1.
Are electrically connected to the individual electrode wirings 1a of the base plate 1 connected to the external electric circuit. in this case,
Although the total number of individual electrodes 31 provided on each light emitting diode element array 3 is as large as several thousands, all of them
At once and firmly electrically connected to the individual electrode wirings 1a adhered to the lower surface of the image device. As a result, the productivity and reliability of the image device become extremely excellent.

The base plate 1 made of the glass epoxy resin is manufactured by pouring a sol-like epoxy resin into glass fibers, and then thermally curing the epoxy resin.
Is a method in which a conductive material such as aluminum is applied to a predetermined thickness by a vapor deposition method, a sputtering method, or the like, is processed into a predetermined pattern by an etching method, and then nickel plating and gold plating are performed on the surface, thereby forming the lower surface of the base plate 1. Is formed.

An opening 1b is provided at the center of the base plate 1. The opening 1b has a function of transmitting light emitted from each light emitting diode element 3a of the light emitting diode element array 3 described later to the lens 6 side. The base plate 1 is formed into a predetermined shape at the center of the base plate 1 by subjecting the base plate 1 to a well-known drilling process.

Further, the light emitting diode element array 3 arranged and mounted on the lower surface of the base plate 1 comprises a plurality of light emitting diode elements 3a.
Respectively, selectively emit light in response to an external electric signal, and irradiate the emitted light to the surface of the photoconductor P to cause the photoconductor P to emit light.
To form a latent image for forming an image.

The light emitting diode element 3a is of GaAsP type, Ga
P-based light-emitting diodes are used.For example, in the case of GaAsP-based light-emitting diodes, first, a GaAs substrate is heated to a high temperature in a furnace, and AsH ₃ (arsine), PH ₃ (phosphine), and Ga (gallium) are used. ) Is brought into contact with a gas containing an appropriate amount of GaAsP (gallium-arsenide-phosphorus) single crystal on the substrate surface, and then Si ₃ O 4 is grown on the GaAsP single crystal surface.
An N ₄ (silicon nitride) film with a window is deposited, and the window is exposed to a gas of Zn (zinc).
Zn is diffused into a part of the 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, the number of the light emitting diode elements 3a is 2048 (8 per 1 mm).
Are linearly arranged, specifically, a light emitting diode element array in which 64 light emitting diode elements 3a are one unit.
By linearly arranging 32 3, 2048 light-emitting diode elements 3 a are arranged on the lower surface of the base plate 1.

Further, on the lower surface of the light emitting diode element array 3, an insulating substrate 2 made of plastic such as glass epoxy resin and having a common electrode wiring 2a attached on the upper surface.
Are fixedly joined.

The insulating substrate 2 serves to electrically connect the common electrode 32 provided on each light emitting diode element array 3 to an external electric circuit, and is attached to the upper surface of the insulating substrate 2 as shown in FIG. The common electrode 32 provided on each light emitting diode element array 3 is bonded to the common electrode wiring 2a of the insulating substrate 2 by joining the common electrode 32 provided on each light emitting diode element array 3 to the common electrode wiring 2a via a metal brazing material. It will be electrically connected.

The insulating substrate 2 made of glass epoxy resin or the like is manufactured by, for example, the same method as the base plate 1, and the common electrode wiring 2a is also formed on the base plate 1.
It is formed by the same material and the same method as the individual electrode wiring 1a adhered to the substrate.

The base plate 1 on which the plurality of light emitting diode element arrays 3 are mounted is also provided with a lens plate 5 at a predetermined distance above the base plate 1, and a plurality of holes 5a are formed in the lens plate 5 in a straight line. The lenses 6 are adhesively fixed via an adhesive such as resin so as to cover the holes 5a.

The lens plate 5 functions as a supporting member for supporting a plurality of lenses 6 on an upper surface at predetermined intervals,
The hole 5a has a function of transmitting light emitted from each light emitting diode element 3a of the light emitting diode element array 3 to the lens 6.

The lens plate 5 is made of a material having substantially the same thermal expansion coefficient as the base plate 1 on which the light emitting diode element array 3 is mounted, such as a glass epoxy resin.
If it is made of a material substantially the same as the thermal expansion coefficient of the lens plate 5 and the base plate 1, the lens plate 5 and the base plate 1 are substantially insulated even when heat is applied to both the lens plate 5 and the base plate 1 when used as an image forming apparatus. There is no positional deviation between each of the lenses 6 supported on the lens plate 5 and each of the light emitting diode element arrays 3 mounted on the base plate 1 due to thermal expansion by the same amount. The light emitted from the light emitting diode element 3a forms an accurate and clear image on the surface of the photoconductor P via the lens 6, and a high-quality latent image can be formed on the photoconductor P.

Each of the lenses 6 supported by the lens plate 5 receives light emitted from each of the light emitting diode elements 3a.
A lens formed of a transparent resin such as an acrylic resin or a polycarbonate resin or a transparent inorganic material such as a glass, which has a function of irradiating the P-plane, is preferably used.

Each lens 6 is linearly bonded to the lens plate 5 at a predetermined interval by bonding a part of the outer surface of the lens 6 to the lens plate 5 via an epoxy resin-based elastic adhesive.

Further, each of the base plate 1 and the lens plate 5 is fixed to a pair of supports 7, 7 so that each light emitting diode element array 3 and each lens 6 are fixed.
Are provided so as to correspond one-to-one with a predetermined distance.

The fixing of the base plate 1 to the pair of supports 7 1, 7 is performed by placing a first positioning reference surface 71 on the lower portion of the support 7.
The two projections 7a having
The end of the base plate 1 and the elastic body 8 are sandwiched between 7a, 7a, and the elastic body 8 presses the end of the base plate 1 on which a large number of light emitting diode element arrays 3 are mounted against the positioning reference surface 71 of the projection 7a. This is done by letting In this case, the base plate 1 is fixed to the support 7 simply by sandwiching the end thereof together with the elastic body 8 between the two protrusions 7a, 7a of the support 7, so that the base plate 1 is extremely easily fixed to the support 7. And the productivity of the imaging device is greatly improved. At the same time, the end of the base plate 1 on which a large number of light emitting diode element arrays 3 are mounted by the elastic body 8 is pressed against the positioning reference surface 71 of the projection 7a, so that a large number of light emitting diode element arrays mounted on the base plate 1 are provided. 3 can be accurately fixed at a predetermined position.As a result, each light emitting diode element array 3 can be accurately opposed to each lens 6 supported by the lens plate 5, and each light emitting diode element array can be fixed. The light emitted by the light emitting diode element 3a
6, the entire surface of the photoconductor P can be satisfactorily irradiated, and a clear and accurate latent image can be formed on the photoconductor P.

A large number of light emitting diode element arrays 3 are arranged on the first positioning reference surface 71 of the projection 7a provided on the support 7.
The elastic body 8 that presses the base plate 1 on which the base plate 1 is mounted is made of an elastic material such as rubber, plastic, or a metal spring, and is used when the end of the base plate 1 is sandwiched between the two protrusions 7a of the support body 7. At the same time two protrusions 7
It is sandwiched between a and 7a.

Further, for fixing the lens plate 5 to the pair of supports 7, 7, a second projection 7 b is provided on the upper portion of the support 7, and the lower surface of the lens plate 5 is brought into contact with the second projection 7 b. This is performed by bonding and fixing both via an adhesive.

When the upper surface of the second projection 7b provided on the support 7 is used as a second reference surface 72 for positioning the lens plate 5, the lens plate 5 is placed on the second projection 7b. By simply fixing, each lens 6 supported on the lens plate 5 and each light emitting diode element array 3 mounted on the base plate 1 can be accurately opposed with a predetermined interval. Therefore, the light emitted from each light emitting diode element 3a of the light emitting diode element array 3 is a lens.
In order to more accurately form an image by irradiating the photoconductor P through the projection 6, a projection for fixing the lens plate 5 of the support 7 can be used.
It is preferable that the upper surface of 7b is used as a reference surface for positioning the lens plate 5.

Thus, according to the image apparatus of the present invention, each light emitting diode element 3a mounted on the base plate 1
A predetermined power is applied to each of the light emitting diode elements 3a to selectively and individually emit light, and the light emitted by each of the light emitting diode elements 3a is imaged on the surface of an external photoconductor P via a lens 6, and By forming a predetermined latent image on the body P, it 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 spirit of the present invention. In addition, if the light-shielding plate 9 is arranged between the adjacent light-emitting diode element arrays 3, the light emitted from the light-emitting diode elements 3a of each light-emitting diode element array 3 may leak to the adjacent light-emitting diode element array 3 side even if it is leaked. Is completely blocked by the light-shielding plate 9, and as a result, the light emitted from the light emitting diode elements 3a of each light emitting diode element array 3 is irradiated and imaged on the photoconductor P only through the corresponding lens 6 on a one-to-one basis. On the other hand, there is no bleeding or the like due to unnecessary light irradiation on the photoconductor P, and an extremely clear latent image can be formed. Therefore, it is preferable to arrange a light shielding plate 9 between the base plate 1 and the lens plate 5 and between the adjacent light emitting diode element arrays 3.

Although the base plate 1 is made of glass epoxy resin in the above embodiment, it may be made of a transparent inorganic material such as glass or a transparent plastic such as acrylic resin. In this case, since the base plate 1 itself is transparent, it is not necessary to provide the base plate 1 with an opening 1b for transmitting the light emitted from the light emitting diode element 3a to the lens 6 side.

Further, in the above-described embodiment, the case where the present invention is used for an image forming apparatus such as an optical printer head has been described. However, the light emitting diode element array is changed to a solid-state image sensor array and the image reading apparatus such as an image sensor is used. Can also be used.

[0038]

According to the image apparatus of the present invention, the individual electrodes of each image element are electrically connected by face-down bonding to the individual electrode wiring previously formed on the surface of the base plate. Even if there are thousands of individual electrodes, all of them will be electrically connected to the individual electrode wirings of the base plate at once and firmly, and as a result, the productivity and reliability of the image apparatus will be extremely excellent.

According to the image apparatus of the present invention, the support is provided with two projections having a positioning reference surface, and the base plate and the elastic body are sandwiched between the two projections. Since the base plate on which a large number of image element arrays are mounted can be fixed to the support by simple work because it is pressed against the surface, and the large number of image element arrays mounted on the base plate are accurately fixed at predetermined positions, Each image element array can be accurately opposed to each lens supported by the lens plate. Therefore, when this image apparatus is used in an image forming apparatus such as an optical printer head, the center of each lens is always located at the center of the light emitting diode element array, and the light emitted from the light emitting diode elements of each light emitting diode element array Irradiates the entire surface of the photosensitive member satisfactorily, and a clear and accurate latent image can be formed on the photosensitive member. At the same time, when this image device is used in an image reading device such as an image sensor, since each lens and each image element array always face accurately, external image information is transferred to the solid-state image sensor array via the lens. An image can be accurately formed on the entire surface, and an accurate electric signal corresponding to external image information can be generated in the solid-state imaging device array.

[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 an enlarged sectional view taken along line XX of FIG.

FIG. 3 is an enlarged sectional view of a main part for describing a mounting state of a light emitting diode element array on a base plate of the image device shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base plate 1a ... Individual electrode wiring 3 ... Light emitting diode element array 3a ... Light emitting diode element 5 ... Lens plate 6 ... Lens 7 ... Supporter 7a ... Two protrusions 71 ... Positioning reference plane 8 ... Elastic body

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-137337 (JP, A) JP-A-7-177301 (JP, A) JP-A-6-326683 (JP, A) 3904 (JP, A) JP-A-4-111391 (JP, A) JP-A-52-4726 (JP, A) JP-A-58-128762 (JP, A) JP-A-4-81067 (JP, A) JP-A-5-121710 (JP, A) JP-A-2-88372 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04N 1/024-1/036 H01L 27/14

Claims (1)

(57) [Claims] 1. A lens plate comprising a plurality of lenses linearly arranged and supported at predetermined intervals, and a base plate having a large number of image element arrays linearly arranged and mounted thereon, said lens plate and said base plate being supported. What is claimed is: 1. An image apparatus, comprising: a lens and an image element array arranged side by side so as to correspond to each other in a one-to-one correspondence, wherein said image element array is mounted on a base plate by face-down bonding; An image apparatus comprising: two projections each having a surface; a base plate and an elastic body sandwiched between the two projections; and the elastic body presses the base plate against a positioning reference surface of the projection.