JPS62290262A - Contact type image sensor - Google Patents

Abstract

PURPOSE:To reduce assembling man-hour and to obtain accurate electrical connection between substrates, by producing a state where a sensor substrate is sandwiched between a driving circuit substrate, and a mount supporting plate. CONSTITUTION:On a glass substrate 31, a light receiving array 12 is formed as a chip through the use of a thin film forming technique. On an opposing plane at the glass substrate 31 side of a sensor driving circuit printed board 33, a pattern electrode 33A corresponding to a pattern electrode 12A on the glass substrate 31 is formed, and an interconnector 34 is fitted and connected in the window 32A of the pattern electrode 12A, and furthermore, the printed board 33 is overlapped on the rubber frame 32 of the glass substrate 31 positioned on a mount supporting plate 23. In this way, operability can be improved, and also, such constitution contributes to the elimination of various kinds of conventional defects, and reliability as a reader can be heightened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a contact type image sensor, and more specifically, to a contact type image sensor for photoelectrically converting image information obtained from an image surface of a document by optical means in an image reading device. The present invention relates to a contact type image sensor configured by arranging solid-state image sensors.

[Conventional technology]

Conventionally, in this type of contact image sensor, the length of the sensor array has been configured to be approximately the same as the scanning width of the original so that it can read the original at the same magnification, which reduces the overall cost of the sensor. For this reason, the sensor uses a thin flat plate made of glass or the like as a substrate to allow human-powered light to pass through it. Further, the input/output signal lines to the sensor are often formed as a pattern by thin film deposition or the like, and the size of the pattern is generally about 1 mm in width and about 2 ml1 in pitch.

Furthermore, the sensor drive circuit is installed on a separate printed circuit board, but the connection between such a drive circuit and the input/output signal line pattern on the sensor board is done by soldering a connector or directly soldering a wire between the two. Because it is difficult to do so, an interconnector is used for -112. Interconnectors are used for electrical connections between liquid crystal panels and printed circuit boards that are separate from the panels in calculators, etc., and have wire diameters or wires that are much smaller than the line width and pitch width of the wiring patterns as described above. It is a rectangular or cylindrical connecting member in which a conductive portion with a line width is covered with an elastic body.

When using such an interconnector, a pattern with a line width and pitch that matches the pattern on the sensor side is usually formed on the side of the drive circuit printed circuit board facing the sensor, and the interconnector is connected between the two sides. is configured such that it is held between the two.

However, in the conventional connection structure using such an interconnector, if the pattern of the human output signal line on the sensor board side and the pattern of the drive circuit printed circuit board do not completely match and overlap, problems may occur during imaging. There is a risk that the human output line may be short-circuited or electrically disconnected. Therefore, when assembling the device, the above-mentioned positioning requires a lot of effort and is a cause of high costs.

In addition, it must be fixed in an aligned state, and conventionally, the sensor was first pressed against the image sensor unit structure by a leaf spring, etc., and then the interconnector and drive circuit board were fixed accordingly. As the process is repeated, the workability is not good and it takes a lot of man-hours.

Furthermore, since the signal level from the image sensor is generally extremely small, it is necessary to increase the contact area per wiring pattern in the above-mentioned electrical connections.
Since one pattern normally has an average size of about 4 to 51I11, if the interconnector is installed in an inclined state, there is a risk that a short circuit will occur between adjacent patterns.

Furthermore, in order to obtain a sufficient electrical connection using an interconnector, the height in the free state before installation is usually about 135 to the height in the installed state of 100. However, when the interconnector is mounted in such a pressed state, both the sensor board on the sandwiching side and the board on the drive circuit side will warp due to reaction force, resulting in loss of flatness. Therefore, there is a possibility that the read image may be out of focus or the wiring pattern may be broken.

[Problem that the invention seeks to solve]

The purpose of the present invention is to focus on the above-mentioned problems, and in order to solve them, the purpose of the present invention is to improve workability, reduce assembly man-hours, and provide a close-contact type that provides reliable electrical connection between boards. Image sensor? It is about providing.

[Means for solving problems]

In order to achieve such an object, the present invention is configured such that an optical system unit can form an image of reflected light obtained from a document, and the formed image is photoelectrically converted by a light-receiving element array provided on a sensor substrate. 4-
A sensor board is sandwiched between a support plate that is attached to the optical system unit by screwing and a circuit board that drives the light receiving element 511, and elasticity is provided between the sensor board and the circuit board. The present invention is characterized in that the circuit board is fixed to the support plate by interposing a connecting member for electrical connection.

[Function] According to the close-contact image sensor of the present invention, the sensor board can be interposed between the circuit board and the sensor board simply by sandwiching the sensor board between the drive circuit board and the mounting support plate. The positioning of the sensor board can be achieved along with the positioning of the electrical connection members, and the assembly of the image sensor can be completed by screwing the printed circuit board to the mounting support plate in this state, which significantly reduces the number of assembly steps compared to the conventional method. Therefore, an inexpensive and highly reliable contact type image sensor can be obtained.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

FIG. 1 shows an example of a document reading device to which the present invention is applied,
Here, the document is guided from the bottom to the reading position by a drive roller and then makes a U-turn toward the top, and an example is shown in which a sensor of equal size is used. That is, 1 is a document, 2 is a driving roller for feeding the document, 3A and 3B are a pair of document guide devices, and 4 is a guide plate on the discharge side. The guide device 3A is connected to an actuator 5, and when the document 1 is guided between the guide devices 3A and 3B, a detector 6 detects this in conjunction with the actuator 5.

7 is an upper cover; 7A is an open cover that is rotatably supported by the upper cover 7 and is opened when a jam occurs in the roller 2; 8 is a support frame that supports the roller 2, etc.; 9 is an open cover that is rotatably supported by the upper cover 7; This is the bottom cover. The original 1 is guided from the direction of arrow B by the above-mentioned original feeding device, and is guided by the driving roller 2.
At the document reading position 10 in contact with the surface of the document, the document is read by the light receiving element array 12 via the reading optical system unit 11, which will be described in detail later, and is ejected by the guide plate 4 in the direction of arrow B'.

Next, the reading optical system unit 11 will be described.
The unit 11 has a shaft support hole 11B provided in its support portion 118.
is rotatably supported on the wall of the structural frame 13 by pins (not shown), and a document holding plate 11G is attached to the side of the roller 2, and the holder IIH of the unit 11 itself is made of drawn aluminum. It is made of wood, die-cast material, or resin-based material. Thus,
As will be described later, the spring force of the coil spring 14 biases the holding plate 11C toward the document l, so that the document l can be held at the reading position 10.

15 is a row of light emitting diodes LED for illumination, 16 is a rod-shaped lens, and 17 is a life-size imaging lens, such as a SELFOC lens, which are attached as shown in FIG. 2, for example. That is, in FIG. 2, 18 is a set screw that fixes the row of imaging lenses 17 to holder IIH from above perpendicular to the front axis, and 19 is holder IIH.
This is a hole for adjusting the position of the lens 17 in the optical axis direction, which is bored in the upper surface of the lens 17, and the lens 17 can be adjusted through the hole 19 with a needle-like adjustment tool. Further, 20 is a set screw for fixing the presser plate 11G to the holder 11)1. Note that among the shaft support holes 11B provided in the holder support portion 11^, one is a circular hole and the other is an oblong hole.

Furthermore, reference numeral 21 denotes a tapped screw hole for fixing a light receiving element assembly unit 22, which will be described later, with screws 24 via a support plate 23. Further, the LED array 15 is formed of a micro square chip by bonding on the substrate 11P, and an external resistor 25 is attached to the substrate 11P by soldering or the like, and the current value in the LED array 15 is adjusted. Ru. 26 is a lens house for fixing the rod-shaped lens 16.

Next, the configuration of the light receiving element assembly unit 22 will be described. In FIGS. 1 and 2, 31 is a glass substrate on which the light receiving element array 12 is disposed, 32 is a rubber frame formed integrally with the substrate 31, and 33 is a printed circuit board for a sensor drive circuit. Therefore, the glass substrate 31, which is integrated with the rubber frame 32, is attached as described later.
The unit 22 can be constructed by integrating the support plate 23 and the above-mentioned printed circuit board 33 into one piece by mounting the support plate 23 on the shelf 23.

That is, in FIG. 3, a light-receiving element array 12 is formed as a chip on a glass substrate 31 using recent thin film formation technology, and furthermore, a pattern electrode 12A and a bonding line 12B from the light-receiving element array 12 and a not-shown A signal processing IC is formed on a glass substrate by vapor deposition and fixed with a transparent adhesive.

Further, 12D is a compound made of rubber or the like to protect the area around the bonding wire 12B, and the rubber frame 32 in which the window 32A is formed in the area where the light receiving element array 12 and the pattern electrode 12A are formed prevents the compound 12D from flowing out during the manufacturing process. is prevented.

On the other hand, for installation, the support plate 23 positions and supports the glass substrate 31, and the surface facing the glass substrate 31 is provided with an embossment 23A protruding around the periphery, and furthermore, both ends of the upper edge of the support plate 23 are provided with cutouts. There are provided projections 23B, by which the four circumferences of the glass substrate 31 can be positioned on the support plate 23. Furthermore, the mounting is performed on the support plate 23, and 23C and 23D are locking claws that lock the substrate 33 side when the printed circuit board 33 is aligned and installed on the rubber frame 32 side of the glass substrate 31 after positioning the glass substrate 31. 23E is attached to the board 3 in such a locked state.
3, 23F is the assembly unit 22
a screw insertion hole for fixing the optical system unit 11 to the optical system unit 11;
3G is a hook portion of the spring 14 shown in FIG.

Next, as shown in FIG. 3, a sensor drive circuit printed circuit board 33 is installed.
To explain this, the board 33 has an engaging end 33C that engages with the recess of the locking pawl 23G of the support plate 23 and an H-shaped constriction of the locking pawl 23D. Engagement notches 330 that fit together are formed at corresponding positions. Further, a pattern electrode 33A is formed on the opposite surface of the printed circuit board 33 on the glass substrate 31 side to correspond to the pattern electrode 12A on the glass substrate 31, and a pattern electrode 33A is formed in the window 32A of the pattern electrode 112A in the shape shown in the figure. After fitting the constructed interconnector 34, the mounting is done on the support plate 23.
With the printed circuit board 33 superimposed and pressed on the rubber frame 32 of the glass substrate 31 positioned above, the engaging end 33G and the engaging notch 330 of the substrate 33 are pressed.
The mounting is performed by locking the locking claws 23G and 23D of the support plate 23, respectively.

Thereafter, the printed circuit board 33 is mounted and fixed to the support plate 23 through the screw hole 33E with the fixing screw 35, and the interconnector 34 is appropriately pressed and brought into pressure contact with the pattern electrodes 12A and 338, respectively. The glass substrate 31 can be held at a correctly positioned position.

Referring again to FIG. 2, the optical system unit 1 as described above is
1 and the light receiving element assembly unit 22 are assembled into the entire document reading device. First, the light receiving element assembly unit 22 is fixed to the optical system unit 11 with the screw 24, and then the shaft support hole of the optical system unit +1 is fixed. 11
Attach the support bottle 3 to B through the threaded hole 13A on the frame 13 side.
6 are attached from both sides. Therefore, the optical system unit 11 and the light receiving element assembly unit 22 are connected to the support pin 3.
At this point, the spring 14 is stretched between the hook 23G of the support plate 23 and the hook 4G provided on the upper guide plate 4. As a result, the entire unit described above is biased toward the drive roller 2 by the spring force, and the optical system unit holder 11)
The presser plate 11G provided at 1 can be maintained in a state where it is lightly pressed by the roller 2.

In addition, in FIG. 2, 37 is a drive pulley of the roller 2;
A belt 38 drives the pulley 37 by a drive source (not shown).

The reading operation of the image reading device configured as described above has been described above, so a description thereof will be omitted. However, in the contact type image sensor according to the present invention, in the structure of the unit, a sensor substrate having a light receiving element array is used. The mounting, which also serves as its positioning, is maintained in a state where it is accurately sandwiched between the support plate and the sensor drive circuit printed circuit board, and in this assembled state, the sensor board and its drive circuit board are By making it possible to position the interconnector, which serves as an electrical connection member between the two, it contributes to the elimination of the shortcomings of the electric field, which is suitable for the electric field. The reliability of the reading device can be improved.

〔Effect of the invention〕

As described above, according to the present invention, the sensor substrate on which the light receiving element array and its pattern electrode are arranged, and the printed circuit board on which the sensor drive circuit is arranged are both mounted by positioning using the support plate. The sensor board is held between the support plate and the printed circuit board, and the connecting member for electrical connection is placed in a predetermined position between the printed circuit board and the sensor board. The printed circuit board is elastically supported, and the printed circuit board is fixed to the board with screws, making the sensor board mounting structure extremely simple and easy to work with.The number of screws is also small, reducing man-hours. This has made it possible to provide an inexpensive contact type image sensor.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the configuration of a document image reading device using a contact image sensor according to the present invention, FIG. 2 is an exploded perspective view of each part of the image reading device, and FIG. 3 is a close contact according to the present invention. FIG. 2 is an exploded perspective view showing the configuration of a light receiving element assembly unit of a type image sensor. l... Original, 2... Roller, lO... Original reading device, 11... Optical system unit, 11B... Pivot hole, llC... Original holding plate, 11) 1... Holder, 12... Light receiving element array, 12A, 33A... Pattern electrode, 15... LED row, 22... Light receiving element assembly unit, 23... Support plate for mounting, 23^... Emboss , 23B... cut-and-raised projection, 23C, 23D... locking claw, 31... glass substrate, 32... rubber frame, 33... printed circuit board, 33G... engaging end, 33D...Engagement notch.

Claims (1)

[Scope of Claims] A document reading device in which an optical system unit forms an image of reflected light obtained from a document, and the image is photoelectrically converted by a light-receiving element array provided on a sensor substrate. In the contact type image sensor, the sensor board is held between a support plate attached to the optical system unit and a circuit board for driving the light receiving element array, and the sensor board is sandwiched between the sensor board and the circuit board. 1. A close-contact image sensor, characterized in that the circuit board is fixed to the support plate by interposing a connecting member having elasticity for electrical connection.