JPH0541803U - Optical printhead mounting structure - Google Patents

Abstract

(57) [Summary] [Objective] The step of forming the electrode pattern of the substrate at the same height as the LED array chip is unnecessary. [Structure] A plurality of light emitting parts 7 and an electrode pattern 8 for inputting a drive signal to the light emitting parts 7 are formed on the upper surface of the LED array chip 1. An external input electrode pattern 5 for inputting an externally input drive signal to the LED drive element 4 is formed on the upper surface of the substrate 2. The input electrode and the output electrode (not shown) of the LED driving element 4 are provided with the protruding electrodes 6 made of, for example, solder in order to connect to the external input electrode pattern 5 and the electrode pattern 8, respectively. Then, the LED array chips 1 are arrayed and fixed at a predetermined position on the side surface of the substrate 2 via a conductive resin 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an optical print head using an LED array as a light source, and more particularly to a mounting structure of the optical print head.

[0002]

[Prior Art]

 Conventionally, as a technique in this field, there is one described in JP-A-2-3354. The mounting structure will be described below. 5A and 5B are views showing a mounting structure of the optical print head described in the above document, FIG. 5A is a sectional view, and FIG. 5B is a plan view.

In FIG. 5, reference numeral 21 denotes an LED array chip, on the upper surface of which a plurality of light emitting portions 24 and electrode patterns 29 for inputting drive signals to the light emitting portions 24 are linearly formed. The LED array chips 21 are arrayed and fixed on the metal plate 27 using a conductive resin 28. Further, on the metal plate 27, polyimide was used so that the external input electrode pattern 25 for connecting the external optical printer controller (not shown) and the optical print head had the same height as the LED array chip 21 in advance. It is formed via the insulating film 26. Further, solder bumps 23 are formed on the input electrodes and output electrodes (not shown) of the LED drive element 22, and the electrodes 29 on the LED array chip 21, the external input electrode pattern 25 on the insulating film 26, and the LED drive are formed. The element 22 is connected and fixed by the solder bump 23.

[0004]

[Problems to be solved by the device]

 However, in the above-described conventional optical printhead mounting structure, in order to make the upper surface of the LED array chip and the external signal electrode pattern surface at the same height, a multilayering process of forming an electrode pattern on the insulating film must be added. However, there is a problem in that the cost of polyimide, which is a material, increases due to the increase in the thickness of the insulating film, which leads to an increase in cost.

The present invention eliminates the problems of increasing the number of processes and increasing the cost of materials by matching the heights of the upper surface of the LED array chip and the surface of the external input electrode pattern described above. It is an object of the present invention to provide an optical printhead mounting structure that simplifies the process and reduces the cost by adhering it to the side surface of the printhead substrate.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention outputs a driving signal to an LED array chip, which is connected to a substrate having an electrode pattern on the upper surface to which a driving signal is input from the outside and the electrode pattern. In an optical print head including an LED drive element and an LED array chip having an electrode pattern to which a drive signal is input from the LED drive element, the LED array chip is attached to a side surface of a substrate with a conductive resin, and the LED The driving element was directly or indirectly connected to the electrode pattern of the LED array chip.

[0007]

[Action]

 According to the present invention, since the mounting structure of the optical print head is configured as described above, the LED array chip is attached to the side surface of the substrate by the conductive resin, and the LED driving element is directly or indirectly connected to the LED array chip. It is connected to the electrode pattern.

[0008]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1A and 1B are views showing a mounting structure of an optical print head according to a first embodiment of the present invention, wherein FIG. 1A is a sectional view and FIG. 1B is a plan view. In FIG. 1, a plurality of light emitting parts 7 and an electrode pattern 8 for inputting a drive signal to the light emitting parts 7 are linearly formed on the upper surface of the LED array chip 1. Further, an external input electrode pattern 5 for outputting a drive signal input from the outside to the LED drive element 4 is well known on the upper surface of a substrate (hereinafter referred to as a substrate) 2 of an optical print head made of glass epoxy, for example. It is formed by the method of. The input electrode and the output electrode (not shown) of the LED driving element 4 are connected to the external input electrode pattern 5 and the electrode pattern 8 formed on the upper surface of the LED array chip 1, respectively. A protruding electrode 6 made of, for example, is formed. The material of the protruding electrode 6 is not particularly limited as long as it can form an intermetallic compound other than the solder. Further, even if the protruding electrodes are formed on the LED array chip 1 or the external input electrode pattern 5 side on the substrate 2, the same effect can be obtained. Also, an anisotropic conductive adhesive may be used for the connection, and at this time, the formation of the protruding electrode is unnecessary.

In this embodiment, the LED array chips 1 are arrayed and fixed at a predetermined position on the side surface of the substrate 2 via a conductive resin 3. At this time, the extraction electrode 9 formed on the bottom surface of the LED array chip 1 and the extraction electrode 10 formed on the side surface of the substrate 2 are electrically connected. Further, the light emitting unit 7 of the LED array chip 1 faces upward. Then, the LED driving element 4 is bonded to the electrode pattern 5 formed on the upper surface of the substrate 2 and the electrode pattern 8 formed on the upper surface of the LED array chip 1 at the protruding electrode 6.

With the above configuration, the drive signal input to the external input electrode pattern 5 is supplied to the LED array chip 1 via the LED drive element 4, and the light emitting section 7 emits light according to the drive signal. 2 is a sectional view showing a mounting structure of an optical print head according to a second embodiment of the present invention.

In this embodiment, the connection structure between the LED drive element 4 and the external input electrode pattern 5 is the same as that in the first embodiment, but the connection structure between the LED drive element 4 and the LED array chip 1 and the LED array chip 1 are the same. And the connection structure of the substrate 2 are different. That is, in the present embodiment, the electrode pattern 8 of the LED array chip 1 is formed by extending from the upper surface to the side surface of the chip, and the extended portion is output electrode of the LED driving element 4 (not shown) via the protruding electrode 6. No)). Further, the bottom surface of the LED array chip 1 is opposed to the side surface of the substrate 2 and is connected via the conductive resin 3. At this time, the extraction electrode 9 arranged on the bottom surface of the LED array chip 1 and the extraction electrode 10 arranged on the side surface of the substrate 2 are electrically connected. The light emitting portion 7 of the LED array chip 1 faces the side surface opposite to the substrate 2.

FIG. 3 is a sectional view showing a mounting structure of an optical print head according to a third embodiment of the present invention. Also in this embodiment, as in the second embodiment, the connection structure between the LED driving element 4 and the LED array chip 1 and the connection structure between the LED array chip 1 and the substrate 2 are different from those in the first embodiment.

That is, in this embodiment, the second electrode pattern 11 is formed on the side surface and the upper surface of the substrate 2, the side surface of the substrate 2 and the upper surface of the LED array chip 1 are opposed to each other, and a conductive resin (not shown) is used. The second electrode pattern 11 and the electrode pattern 8 are connected via. Further, the portion of the second electrode pattern 11 formed on the upper surface of the substrate 2 is connected to the output electrode (not shown) of the LED driving element 4 via the protruding electrode 6. Further, the extraction electrode 9 formed on the bottom surface of the LED array chip 1 is connected to the extraction electrode (not shown) formed on the substrate 2 by the conductive resin 13. At this time, an insulating film 12 is formed between the conductive resin 13 and the electrode patterns 8 and the second electrode patterns 11 in order to prevent electrical conduction between them. Further, in this embodiment, the light emitting portion 7 of the LED array chip 1 faces the side surface on the base plate 2 side.

FIG. 4 is a sectional view showing a mounting structure of an optical print head according to a fourth embodiment of the present invention. Also in this embodiment, as in the second embodiment, the connection structure between the LED driving element 4 and the LED array chip 1 and the connection structure between the LED array chip 1 and the substrate 2 are different from those in the first embodiment.

In this embodiment, the second electrode pattern 11 is formed on the side surface and the upper surface of the substrate 2, and the electrode pattern 8 of the LED array chip 1 is formed so as to extend from the upper surface to the side surface of the chip. The side surface and the side surface of the LED array chip 1 are opposed to each other, and the second electrode pattern 11 and the electrode pattern 8 are connected via a conductive resin (not shown). The connection structure between the second electrode pattern 11 and the LED driving element 4, and the connection structure between the extraction electrode 9 formed on the bottom surface of the LED array chip 1 and the extraction electrode (not shown) formed on the substrate 2 are the third embodiment. Is the same as.

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention, and these modifications are not excluded from the scope of the present invention.

[0017]

[Effect of the device]

 As described above in detail, according to the present invention, since the LED array chip is adhered to the side surface of the substrate, the following effects can be obtained. (1) The process is simplified because the step of forming the insulating film for forming the substrate electrode pattern at the same height as the LED array chip is not required. (2) Since an insulating film is unnecessary, cost reduction can be realized. (3) Since the LED array chip and the substrate are connected, the optical print head can be miniaturized.

[Brief description of drawings]

FIG. 1 is a view showing a mounting structure of an optical print head according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a mounting structure of an optical print head according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a mounting structure of an optical print head according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a mounting structure of an optical print head according to a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a mounting structure of a conventional optical print head.

[Explanation of symbols]

 1 LED Array Chip 2 Substrate 3,13 Conductive Resin 4 LED Driving Element 5,8 Electrode Pattern 6 Projection Electrode 7 Light-Emitting Section 9,10 Extraction Electrode 11 Second Electrode Pattern 12 Insulating Film

Claims (5)

[Scope of utility model registration request] 1. A substrate having an upper surface on which an electrode pattern to which a drive signal is input is formed, and (b) an electrode pattern connected to the electrode pattern, the drive signal being L
An LED drive element for outputting to the ED array chip; and (c) the LED array chip having an electrode pattern to which the drive signal is input from the LED drive element, and (d) the LED array chip on the substrate. A mounting structure of an optical print head, characterized in that the LED driving element is directly or indirectly connected to an electrode pattern of the LED array chip by being bonded to a side surface with a conductive resin. 2. A side surface of an LED array chip having an electrode pattern formed on an upper surface thereof is adhered to a side surface of a substrate, and an LED is formed.
The mounting structure for an optical print head according to claim 1, wherein a driving element is bonded to an electrode pattern of the LED array chip. 3. The LED array chip having an electrode pattern extending from the upper surface to the side surface is adhered to the bottom surface of the substrate, and the LED driving element is bonded to the electrode pattern on the side surface of the LED array chip. 1. The mounting structure of the optical print head according to 1. 4. An LED driving element, wherein an electrode pattern of an LED array chip having an electrode pattern formed on an upper surface is extended from a side surface to an upper surface and adhered to a second electrode pattern on a side surface of a substrate having a second electrode pattern formed thereon. 2. The mounting structure for an optical print head according to claim 1, wherein is bonded to the second electrode pattern at the end of the upper surface. 5. A side surface of an LED array chip having an electrode pattern formed extending from a top surface to a side surface is adhered to a second electrode pattern on a side surface of a substrate having a second electrode pattern formed extending from the side surface to the top surface, and The mounting structure of the optical print head according to claim 1, wherein the LED driving element is bonded to the second electrode pattern on the upper surface.