JPH0964326A - Image device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable rigid electric connection with the electrode wiring of a base plate at a time, by forming the electrode wiring of metal powder, combining the metal powder by glass which forms the base plate, and sticking the electrode wiring on one surface of the base plate. SOLUTION: On one main surface of a base plate 1, a light emitting diode element array 2 is mounted in the manner in which an electrode wiring 1a stuck on the base plate 1 faces each of the electrodes 2b of the light emitting diode element array 2, interposing solder 4. After that, the solder 4 is heated and melted, the electrode wirings 1a of the base plate 1 are solder-bonded to the electrodes 2b of the light emitting element array 2. Thereby the respective light emitting element arrays 2 are arranged and mounted on the one main surface of the base plate 1. When the total number of the electrodes is very large, all the electrodes are rigidly electrically connected at a time with the electrode wirings 1a.

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 used in 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 Conventionally, an image forming apparatus such as an image forming apparatus such as an optical printer head has a lens made of a resin such as polycarbonate in which a plurality of lenses are linearly arranged and supported at a predetermined interval. A plate and a base plate made of a resin such as polycarbonate on which a large number of light emitting diode element arrays are linearly arranged and mounted;
It has a structure in which each lens and each light emitting diode element array are fixed side by side so as to have a one-to-one correspondence, and each light emitting diode element of each light emitting diode element array is individually selected according to an external electric signal. The light emitting diode element functions as an image forming apparatus by causing the light emitted from the light emitting diode element to form an image on an external photoconductor through a lens to form a latent image on the photoconductor.

A light-emitting diode element array linearly arranged and mounted on the base plate generally has 64 light-emitting diode elements linearly arranged therein, which is suitable for a B4 size image forming apparatus. When used, the 32 light emitting diode element arrays are mounted on the base plate so that each of the 32 light emitting diode element arrays has a one-to-one correspondence with each lens.

Further, in the light emitting diode element array linearly arranged and mounted on the base plate, each electrode thereof is electrically connected to an electrode wiring previously attached to the surface of the base plate through a bonding wire, By connecting the electrode wiring on the surface of the base plate to an external electric circuit, the light emitting diode element of each light emitting diode element array is connected to the external electric circuit via the electrode wiring and the bonding wire.

[0005]

However, in this conventional image device, each electrode of the light emitting diode element array is connected to the electrode wiring of the base plate through a bonding wire, and the number of electrodes of the light emitting diode element array is Since it is extremely large, it takes a long time to electrically connect the electrodes of the light-emitting diode element array to the electrode wiring of the base plate, and the manufacturing workability of the image device is poor, and the image device as a product has the disadvantages of being expensive. Was there.

In the above embodiment, the image forming apparatus used in the image forming apparatus such as the optical printer head has been described as an example. However, in the image reading apparatus such as the image sensor using the solid-state image sensor array, etc. The image device used has the same drawbacks.

Therefore, in order to solve the above-mentioned drawbacks, the applicant of the present invention previously forms a thin film on the surface of a base plate made of a transparent material such as crystallized glass or quartz by forming each electrode formed in the vicinity of the light emitting / receiving area of the image element array in advance. An image device has been proposed in which the electrode wiring formed in a predetermined pattern by the technique is connected by flip-chip connection via solder.

According to such an image device, since the electrodes of the image element array are connected to the electrode wirings attached to the base plate by flip chip connection, even if the number of electrodes of the image element array is large, all of them are the electrode wirings of the base plate. Then, the electric connection is made firmly at once and, as a result, the productivity of the image device becomes extremely excellent.

However, in this image device, since the surface of the base plate made of crystallized glass, quartz or the like is smooth, the base plate is deposited in a predetermined pattern by a thin film forming technique such as vapor deposition, sputtering or ion plating. The adhesion strength of the electrode wiring is weak, so when the electrodes of the image element array are flip-chip connected to the electrode wiring applied to the base plate via solder, the electrode wiring is peeled off from the base plate, and This has led to the drawback that the electrodes cannot be securely and firmly electrically connected to an external electric circuit.

[0010]

The present invention has been devised in view of the above-mentioned drawbacks, and has a lens member composed of a plurality of lenses and electrode wiring on one main surface side, and a large number of electrode wirings are provided. Each lens and each image element array have a one-to-one correspondence with a base plate made of translucent glass on which a large number of image element arrays are linearly arranged and mounted by flip-chip connecting the electrodes of the image element array In the image device fixed side by side as described above, the electrode wiring is formed of a metal powder, and the metal powder is bonded to the glass forming the base plate to attach the electrode wiring to one surface side of the base plate. It is characterized by that.

According to the image device of the present invention, each electrode of the image element array is electrically connected to the electrode wiring adhered to the one main surface side of the base plate by flip-chip connection. However, all of them are electrically connected to the electrode wiring of the base plate at once and firmly, and as a result, the productivity of the image device is extremely excellent, and the image device as a product is inexpensive. Becomes

Further, according to the image device of the present invention, the electrode wiring is formed on the one surface side of the base plate by forming the electrode wiring with the metal powder and bonding the metal powder with the glass forming the base plate. Therefore, the adhesion strength of the electrode wiring to the base plate becomes extremely strong. As a result, the electrode wiring is peeled from the base plate even if the electrodes of the image element array are flip-chip connected to the electrode wiring adhered to the base plate through solder. Therefore, each electrode of the image element array can be reliably and firmly electrically connected to the external electric circuit.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described in detail with reference to the accompanying drawings. 1 to 3 show an embodiment in which the image forming apparatus of the present invention is adopted as an image forming apparatus in an optical printer head, 1 is a base plate, 2 is a light emitting diode element array, and 3 is a lens member.

The base plate 1 is made of, for example, borosilicate translucent glass, and a plurality of light emitting diode element arrays 2 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 2, and as shown in FIG. 3, the electrode wiring 1a attached to one main surface of the base plate 1 is provided with each light emitting diode element array 2. Each electrode 2b
Flip-chip connection, specifically, the light emitting diode element array 2 is attached to one main surface side of the base plate 1, and the electrode wiring 1a attached to the base plate 1 and each electrode 2b of the light emitting diode element array 2 are soldered between them. 4 are placed so as to face each other, and then the solder 4 is heated and melted, and each electrode wiring 1a of the base plate 1 and each electrode 2b of the light emitting diode element array 2 are solder-bonded to each light emitting diode. The element array 2 is arranged and mounted on the one main surface side of the base plate 1. In this case, even if the total number of the electrodes 2b of each light emitting diode element array 2 is extremely large, all of the electrodes 2b are attached to the electrode wiring 1a attached to the one main surface side of the base plate 1 at a time through solder, and Since the electrodes 2b of the light-emitting diode element array 2 and the electrode wirings 1a of the base plate 1 can be electrically connected to each other because of the strong electrical connection, workability and productivity of assembling the image device can be improved. Is greatly improved.

Since the base plate 1 is made of translucent glass, its central region directly serves as a window for forming a light passage between the light emitting diode element eye 2 and the lens 7 described later. .

The electrode wiring 1a previously attached to one main surface of the base plate 1 has a function of connecting each electrode 2b of the light emitting diode element array 2 to an external electric circuit. For example, first, the base plate 1 is used. A resist film made of a novolac resin or the like is applied to one main surface so as to form holes of a predetermined pattern, and then gold is applied to the holes of the resist film.
Fill the metal paste obtained by adding and mixing an organic binder, a solvent, etc. to a metal powder such as silver, platinum, copper, etc., and then bake this at a temperature of about 600 ° C. The binder, the solvent, and the like are burned off, and the metal powder is bonded to the glass forming the base plate 1 to be applied to one surface side of the base plate. In this case, since the metal powder forming the electrode wiring 1a is bonded to the glass forming the base plate 1, the electrode wiring 1a has a very strong adhesion strength to the base plate 1 and, as a result, the base plate 1
Even if each electrode 2b of the light emitting diode element array 2 is flip-chip connected to the electrode wiring 1a adhered to the substrate via the solder 4, the electrode wiring 1a does not peel off from the base plate 1 and each of the light emitting diode element array 2 The electrode 2b can be reliably and firmly electrically connected to the external electric circuit.

Further, the electrode wiring 1a and the light emitting diode element array 2 which are previously deposited on the surface of the base plate 1 are arranged.
When the solder 4 for connecting each of the electrodes 2b of the above is applied to the surface of the electrode wiring 1a by solder plating to a predetermined thickness in advance, the electrode wiring 1a of the base plate 1 and each electrode 2b of the light emitting diode element array 2 are opposed to each other. The workability of flip-chip connection between the electrode wiring 1a attached to the base plate 1 and each electrode 2b of the light emitting diode element array 2 is automatically simplified by automatically arranging between the electrode wiring 1a and each electrode 2b. Becomes Therefore, the solder 4 connecting the electrode wiring 1a attached to the surface of the base plate 1 and each electrode 2b of the light emitting diode element array 2 is the electrode wiring 1a.
It is preferable to apply a predetermined thickness by solder plating to the surface of the above.

Further, the light emitting diode element array 2 arranged and mounted on the base plate 1 comprises a plurality of light emitting diode elements 2a.
a selectively emits light individually in response to an external electric signal, and irradiates the surface of the photoconductor P with the emitted light to form a latent image for forming an image on the photoconductor P.

The light emitting diode element 2a is GaAsP.
-Based, GaP-based light-emitting diodes are used, for example, Ga
In the case of an AsP-based light-emitting diode, first, a GaAs substrate is heated to a high temperature in a furnace, and a gas containing an appropriate amount of AsH ₃ (arsine), PH ₃ (phosphine) and Ga (gallium) is brought into contact with the substrate. GaA of n-type semiconductor on the surface
A single crystal of sP (gallium-arsenic-phosphorus) is grown, and then Si ₃ N ₄ (silicon nitride) is formed on the surface of the GaAsP single crystal.
The windowed film is deposited and Zn (zinc) gas is exposed to the window to diffuse Zn into a part of the GaAsP single crystal of the n-type semiconductor to form a p-type semiconductor, which has a pn junction. It is formed by

In the case of a B4 size optical printer head, 2048 light emitting diode elements 2a (8 per 1 mm) are linearly arranged. Specifically, 64 light emitting diode elements 2a are regarded as one unit. By arranging 32 light emitting diode element arrays 2 described above in a straight line, 2048 light emitting diode elements 2a are mounted on the base plate 1 in an array.

On the other hand, the base plate 1 on which the light emitting diode element array 2 is arranged and mounted is provided with a lens member 3 on its upper part at a predetermined distance, and the lens member 3 has a plurality of through holes 6a formed in a straight line. It is composed of a lens plate 6 which is arranged in a line and a lens 7 which is adhered and fixed to the lens plate 6 through an adhesive such as a resin so as to close the through hole 6a.

The lens plate 6 of the lens member 3 acts as a supporting member for supporting a plurality of lenses 7 on the upper surface at a predetermined interval, and the through holes 6a are emitted by each light emitting diode element 2a of the light emitting diode element array 2. The light is transmitted to the lens 7.

Each lens 7 supported by the lens plate 6 transmits light emitted from each light emitting diode element 2a to the photoconductor P.
A lens formed of a transparent resin such as an acrylic resin or a polycarbonate resin or a transparent inorganic material such as glass, which has the function of irradiating the surface, is preferably used.

The lenses 7 are linearly adhered to the lens plate 6 at predetermined intervals by adhering a part of the outer surface to the lens plate 6 with, for example, an epoxy resin adhesive.

Furthermore, the base plate 1 on which the light emitting diode element array 2 is mounted and the lens member 3 having a plurality of lenses 7 are fixed to the spacers 8 so that each light emitting diode element array 2 and each lens 7 are fixed.
And are placed side by side so as to correspond one to one with a predetermined distance.

The spacer 8 has a first alignment reference surface 8a on its upper portion and a second alignment reference surface 8b on its lower portion, and the lens member 3 is formed on the first alignment reference surface 8a of the spacer 8. The lower surface of the lens plate 6
By fixing the outer peripheral portion of the upper surface of the base plate 1 to the alignment reference surface 8b, each light emitting diode element array 2 and each lens 7 are in a one-to-one correspondence with a predetermined distance therebetween.

Thus, according to the image device of the present invention, a predetermined electric power is applied to each of the light emitting diode elements 2a arranged and mounted on the base plate 1 to cause each of the light emitting diode elements 2a to individually and selectively emit light. The light emitted from each light emitting diode element 2a is imaged on the surface of the external photoconductor P via the lens 7 of the lens member 3, and a predetermined latent image is formed on the photoconductor P to function as an image forming apparatus.

The present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above-mentioned embodiments, the lens member 3 is used. A lens plate 6 having a plurality of through-holes 6a arranged linearly and having a plurality of lenses 7 adhered and fixed thereto is used. This is a so-called cell in which a large number of rod-shaped self-focusing lenses are arranged. You may change to a Fock lens.

Further, in the above-mentioned embodiment, the case of using it in an image forming apparatus such as an optical printer head has been described as an example. However, the light emitting diode element array is replaced with a solid snow image element array, and an image reading apparatus such as an image sensor. It can also be used for.

[0031]

According to the image device of the present invention, each electrode of the image element array is electrically connected to the electrode wiring adhered to the one main surface side of the base plate by flip-chip connection. Even if the number of electrodes is extremely large, all of them will be electrically connected to the electrode wiring of the base plate at once and firmly, and as a result, the productivity of the image device will be extremely excellent and the image device as a product Will be cheaper.

According to the image device of the present invention, the electrode wiring is formed on the one surface side of the base plate by forming the electrode wiring with the metal powder and bonding the metal powder with the glass forming the base plate. Therefore, the adhesion strength of the electrode wiring to the base plate becomes extremely strong. As a result, the electrode wiring is peeled from the base plate even if the electrodes of the image element array are flip-chip connected to the electrode wiring adhered to the base plate through solder. Therefore, each electrode of the image element array can be reliably and firmly electrically connected to the external electric circuit.

[Brief description of drawings]

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

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a partially enlarged cross-sectional view for explaining a connection state between an electrode wiring of a base plate and an electrode of an image element array.

[Explanation of symbols]

 1 ... Base plate 1a ... Electrode wiring 2 ... Light emitting diode element array 2a ... Light emitting diode element 2b ... Electrode 3 ... Lens member 6-Lens plate 7-Lens 8-Spacer P-Photoreceptor

Claims (1)

[Claims] 1. A lens member comprising a plurality of lenses and electrode wiring on one main surface side, and by flip-chip connecting electrodes of a large number of image element arrays to the electrode wiring, a large number of image element arrays are formed. An image device in which a base plate made of translucent glass, which is linearly arranged and mounted, is fixed side by side so that each lens and each image element array have a one-to-one correspondence, and the electrode wiring is a metal powder. Formed by
Further, an image device characterized in that electrode wiring is adhered to one surface side of the base plate by bonding the metal powder with glass forming the base plate.