JPH06291939A - Led light source device, reader and reader integrating device - Google Patents

Abstract

PURPOSE:To simplify the structure by extending part of a mount base to a mount side of a light emitting diode of a circuit board to form a reflecting face of a light around the light emitting diode thereby preventing mis-alignment of an optical axis and ununiform illuminance. CONSTITUTION:A circuit board 5 is mounted on a resin-made mount base 2 and part of the mount base 2 is extended to an LED mount face of the circuit board 5 and the tip reaches both sides of an LED 6. Then the mount base 2 is formed to be a slope extended in a direction of a read original at both sides of the LED 6, and mirror finish is applied to the surface of the slope to form a reflecting face 3 of a light from the LED 6. Moreover, the reflecting face 2 has an angle at which the light from the LED 6 is reflected almost in a collimated ray. In the LED light source as above, the light from the LED 6 is collimated by the reflecting face 3 and radiates toward the paper face of the read original 9, then it is prevented that illuminance is high at a focal position and illuminance is low before and after the focal point different from the use of a condenser lens.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a light emitting diode (hereinafter referred to as L
The present invention relates to an LED light source device for an optical reading machine such as a facsimile using an ED), and more particularly to an LED light source device that can prevent misalignment of optical axes and uneven illuminance and has a simple structure.

[0002]

LEDs are commonly used in optical reading machines.
A light source device using is used. This LED light source device has a structure in which a circuit board on which LEDs are mounted is mounted on a mounting base. In the conventional LED light source device, a lens for condensing light is mounted on the LED light emitting surface in order to irradiate a sufficient amount of light onto the paper surface of the reading document.

FIG. 8 shows a conventional LED equipped with a condenser lens.
The external appearance of a light source device is shown. Conventional LED light source device 5
The reference numeral 1 fixes a circuit board 53 for controlling the light emission of the LED on the upper surface of the mounting base 52, and an L (not shown) is mounted on the circuit board 53.
The EDs are arranged linearly, and a condenser lens 54 having a convex lens in cross section is attached on the LED row. Circuit board 5
A lead wire 55 is connected to one end of 3.

FIG. 9 shows a cross section of the LED light source device 51. The mounting base 52 is made of resin, the upper surface is inclined at a predetermined angle, the circuit board 53 is fixed to the upper surface of the mounting base 52, and the LED 56 and the current limiting resistor 57 are mounted on the circuit board 53. A condenser lens 54 made of transparent resin is mounted on the LED 56. The condenser lens 54 is composed of two components, a convex lens 54a and a lens case 54b.

In order to properly mount the LED light source device 51, as shown in FIG. 10, the LED 56 is correctly installed at the light emitting position, and the center of the convex lens 54a of the condenser lens is L.
It must be properly aligned with the center of the ED 56. In FIG. 10, reference numeral 58 indicates a glass on which a read document is placed.

However, as described above, it is not easy to properly mount the LED 56. FIG. 11 shows a case where the optical axes of the LED 56 and the condenser lens 54 are deviated.
In FIG. 11, the LED 56 is not correctly installed at the light emitting position, and the center of the condenser lens 54 is not aligned with the optical axis of the irradiation light. In other words, in order to properly mount the above-mentioned conventional LED light source device 51, a double error in the mounting positions of the LED 56 and the condenser lens 54 must be within a predetermined range.

On the other hand, an LED light source device has been proposed in which the center of the condenser lens and the center of the LED can be easily aligned with each other (see Japanese Patent Laid-Open No. 18771).

FIGS. 12 and 13 show the LE proposed above.
The D light source device is shown. The condensing lens 62 of this LED light source device 61 has an integral structure, and as shown in FIG.
It has a convex lens portion protruding vertically above the LED 56. The condensing lens 62 is L by the convex lens portion.
It is easy to align the position with the ED 56, and it is possible to reduce the difficulty of mounting the LED and the condenser lens.

However, the conventional LED light source device 61 cannot solve the problem of uneven illuminance due to a change in the distance between the read document and the LED 56. That is, as shown in FIG. 14, the read original 63 is usually slightly wavy, and the paper surface is partly apart from the upper surface P of the glass 58. On the other hand, the focal point F of the condenser lens 62 is the glass 5
It is set in the lower part of 8, and is set so that a constant illuminance can be obtained on the upper surface P of the glass 58. Therefore, glass 5
8 has a problem that the portion of the read document 63 separated from the surface P of No. 8 spreads light due to the action of the convex lens and the illuminance is insufficient.

For the LED light source device 61,
An LED light source device has been proposed in which parallel light is radiated by an LED structure incorporating the.

FIG. 15 and FIG. 16 show an LED light source device in which parallel light is emitted by the LED structure. In this LED light source device 71, a circuit board 53 is mounted on the upper surface of a mounting base 52, and an LE is mounted on the circuit board 53.
An LED structure 72 incorporating D and a current limiting resistor 57 are mounted.

The LED structure 72 has a structure in which an LED is incorporated in a lower portion of a light transmitting body made of a transparent resin, the light emitted from the LED is transmitted by the light transmitting body, and parallel light is emitted from the upper surface. .

According to this LED light source device 71, since the emitted light is a parallel light beam, the light spreads even when the paper surface of the read document is separated from the surface of the glass on which the document is placed. And there is no significant decrease in illuminance. Further, since the work of aligning the optical axes of the condenser lens and the LED is not necessary, the manufacture of the LED light source device is simple.

[0014]

However, the above-mentioned conventional LED light source device which does not use a lens has a large number of LEDs.
The structure had to be manufactured and assembled.

Further, in the above LED structure, the light of the LED is L
Since the light was scattered while passing through the ED structure and the condenser lens was not used, the amount of light applied to the read document tended to be insufficient.

On the other hand, a large number of conventionally manufactured L
In order to select and use one having a large light emission amount from the ED structure and to efficiently receive the reflected light, the assembled LED light source device is brought as close as possible to the paper surface of the read original, and A high precision CCD light receiving element was used.

As a result, the ratio (so-called yield) of the LED structure or CCD light receiving element that conforms to the standard is low, and the restrictions on the structure of the LED light source device as described above are large.

Therefore, an object of the present invention is to provide the above conventional LED.
LE of the optical reading machine which solves the problem of the light source device, prevents the misalignment of the optical axis and the unevenness of the illuminance, and has a simple structure.
It is to provide a D light source device.

[0019]

In order to achieve the above object, an LED light source device according to the present invention is an LED light source device in which a circuit board on which a light emitting diode is mounted is mounted on a mounting base. It is characterized in that a light reflecting surface is formed around the light emitting diode so as to extend to a mounting surface of the light emitting diode on the circuit board.

Further, a reading device of the present invention comprises the above-mentioned LED light source device, an irradiated object for receiving the light output from the device, and a light receiving device for receiving reflected light from the irradiated object. It is a feature.

Further, an apparatus incorporating the reading apparatus of the present invention is characterized by including the above-mentioned reading apparatus and means for reproducing a read image.

[0022]

In the LED light source device of the optical reading machine according to the present invention, a part of the mounting base extends to the LED mounting surface of the circuit board, and a light reflecting surface is formed around the LED. The reflective surface reflects the light of the LED, and a condenser lens or LE
The structure is simple without requiring a large number of parts such as the D structure.

In the LED light source device of the present invention, almost all of the LED light is reflected by the reflecting surface and is applied to the paper surface of the read document, so less light is scattered than the LED structure and a high illuminance can be obtained. You can

Further, since the light rays emitted from the LED light source device of the present invention are emitted in parallel, the illuminance is unlikely to be non-uniform due to the change in the distance between the paper surface and the light emitting surface.

Further, it is possible to obtain the LED light source device of the optical reading machine which is easy to manufacture as a whole in combination with the above-mentioned actions, because the labor of aligning the optical axes of the lenses and attaching a large number of LED structures at the time of assembly can be omitted.

Since the reader according to the present invention is provided with the above-mentioned LED light source device, a reader which is easy to manufacture can be obtained by the above operation.

Further, since the reader built-in device according to the present invention has the above-mentioned reader, a reader built-in device that is easy to manufacture can be obtained.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention basically utilizes a part of the mounting base to make the L
A light reflecting surface is formed around the ED to irradiate light parallel to the paper surface of the read document. Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the appearance of an LED light source device of an optical reading machine according to the present invention. The LED light source device 1 according to the present invention is linearly L-shaped.
It has an ED-mounted circuit board and has an elongated shape as a whole in appearance. In FIG. 1, a mounting base 2 made of resin contains a circuit board (not shown) and has a slit on the upper surface for exposing the light emitting surface of the LED. The mounting base 2 is formed as an inclined surface on both sides of this slit, and forms a light reflecting surface 3 described later. A lead wire 4 is taken out from one end of the LED light source device 1, and the lead wire 4 is connected to a circuit board.

FIG. 2 shows a cross section of the LED light source device 1. As shown in FIG. 2, the LED light source device 1 has a circuit board 5 that controls blinking of light, and LEDs 6 are linearly mounted on one surface of the circuit board 5. Reference numeral 7 indicates a current limiting resistor, which is mounted on the circuit board 5.

The circuit board 5 is attached to a mounting base 2 made of resin, and a part 2a of the mounting base 2 is an LED of the circuit board 5.
It is extended on the mounting surface, and its tip reaches both sides of the LED 6. The mounting bases 2 are formed on both sides of the LED 6 in an inclined surface that expands in the direction of the read document (not shown). The surface of this inclined surface is mirror-finished, and forms the reflection surface 3 of the light of the LED 6.

The operation of the LED light source device 1 of the present invention will be described below based on the above structure. FIG. 3 shows a light irradiation state by the LED light source device 1. The reflecting surface 3 is shown in FIG.
As shown in FIG. 5, the LED 6 is formed at an angle that reflects the light of the LED 6 into substantially parallel light rays. Reference numeral 8 indicates a transparent glass on which the read original is placed, and reference numeral 9 indicates a read original placed on the glass 8.

Reference numeral 81 schematically indicates a light receiving device of a reading device equipped with the LED light source device 1. Light receiving device 81
Has a light receiving portion 82, and the light receiving portion 82 is fixed on the base body 83.

The light receiving portion 82 is arranged at a position for receiving the reflected light R emitted from the LED 6 and hitting the read original 9 and reflected. The light receiving device 81 converts the read image reflected on the light receiving unit 82 into an electric signal or the like and outputs it.

Since the operation of the reading device or the device incorporating the reading device of the present invention almost belongs to the operation of the LED light source device 1, the operation of the LED light source device 1 will be mainly described below.

According to the LED light source device 1 of this embodiment, L
The light from the ED 6 becomes parallel light rays by the reflecting surface 3 and is radiated toward the paper surface of the read document 9. This allows
The illuminance is high at the focal position like the conventional condenser lens,
The illuminance is not low before and after the focal point, and even when the distance between the paper surface of the read document 9 and the LED 6 changes slightly due to the waviness of the paper, a substantially constant illuminance can be obtained on the reading surface.

Further, according to the LED light source device 1 of the present embodiment, almost all of the light of the LED 6 is reflected by the reflecting surface 3 and irradiates the read original 9, so that the light is emitted like the LED structure of the prior art. Is not scattered, and a large amount of light can be applied to the reading surface.

Further, according to the LED light source device 1 of this embodiment, special parts such as a condenser lens and an LED structure can be omitted, and an LED light source device having a simple structure and easy manufacturing can be obtained.

Next, another embodiment of the LED light source device of the present invention will be described.

Although the reflecting surface 3 of the above embodiment reflects light efficiently by mirror finishing, it goes without saying that it may be plated finishing instead of mirror finishing.

FIG. 4 shows a second embodiment of the present invention. The same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted. In the LED light source device 11 of the second embodiment,
A tape 12 that reflects light is attached to the light reflecting surface 3. According to this embodiment, the steps of mirror-finishing or plating the reflecting surface 3 can be omitted, and the manufacturing becomes easier.

Further, the plating-finished reflection surface 3 may be deteriorated due to oxidation of the plating due to heat or air, but the tape 12 can prevent the above inconvenience.

FIG. 5 shows a third embodiment of the present invention. 5, the same parts as those in FIGS. 2 and 4 are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, the transparent resin 22 is filled in the recess formed by the reflecting surface 3. In FIG. 5, the resin 22 is filled in the state where the tape 12 is stuck on the reflecting surface 3, but the reflecting surface 3 may be plated or the like.

According to this embodiment, the heat of the reflecting surface 3 is generated by the resin 2
Since the heat is radiated through 2, the temperature rise of the concave portion including the reflecting surface 3 can be suppressed. When the reflecting surface 3 is plated, the plating is protected by the resin and oxidation is prevented.

In each of the above embodiments, the reflecting surfaces are all formed flat, but the shapes of the reflecting surface and the light irradiation surface of the present invention are not limited to this, and any shape that reflects light may be used. You can For example, the reflection surface can be formed into a curved surface to increase the illuminance of the read document.

FIG. 6 shows a fourth embodiment of the present invention. 6, the same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted. LED light source device 31 of this embodiment
The reflecting surface 32 has a spherical surface in cross section. Further, the concave portion of the reflecting surface 32 is filled with resin 33.

According to this embodiment, the light from the LED 6 is concentrated near the read original by the reflecting surface 32. In this case, the illuminance of light slightly changes due to the change of the read document and the LED 6, but instead the light of high illuminance can be applied to the reading surface.

The suppression of the temperature rise in the concave portion of the reflecting surface 32 and the prevention of the oxidation of the plating are shown in FIG.
This is the same as the case of the third embodiment.

FIG. 7 shows a fifth embodiment of the present invention. The LED light source device 41 of the fifth embodiment has substantially the same structure as that of the fourth embodiment of FIG.
The surface 43a of the resin 43 filled in the second recess is spherical. Although the operation and effect of the LED light source device 41 of the fifth embodiment is almost the same as that of the LED light source device 31 of the fourth embodiment, the light of the LED 6 can be collected more efficiently by the depression of the surface of the resin 43.

LED light source device 1, 11, 21, 3
The reader using 1, 41 has the above advantages as they are, and as a result, a reader which is easy to manufacture can be obtained.

Finally, FIG. 8 shows the configuration of a device incorporating a reader having the above reader. The reader built-in device 91 according to the present invention includes LED light source devices 1, 11, 21, 31, 41.
It has a read document 9, a light receiving device 81, and a means 92 for reproducing the read image. The arrows in the figure show the flow of signals and the like from the reader-embedded device 91. That is, in the reading device incorporating apparatus 91 of the present invention, light is output from the LED light source devices 1, 11, 21, 31, and 41, and this light is applied to an irradiation target such as the reading original document 9. The light receiving device 81 converts the read image formed by the light reflected from the irradiation object into an electric signal or the like, and outputs the electric signal to a means 92 for reproducing the read image such as a printer or a CRT.

This reader-embedded device 91 is an L-type device of the present invention.
Since the ED light source device 1 and the like are included, the LED light source device of the present invention has the advantages, and it is possible to obtain a reader built-in device that is easy to manufacture as a whole.

[0052]

As is apparent from the above description, in the LED light source device according to the present invention, the reflecting surface reflects the light of the LED,
Since parallel rays are projected onto the paper surface of the read document, LE
Even when the distance between D and the reading surface changes, the illuminance on the reading surface does not change significantly.

Further, since almost all of the LED light is reflected and irradiates the read document, the illuminance on the reading surface is less likely to decrease due to light scattering.

As described above, according to the present invention, since the light from the LED is efficiently irradiated in parallel to the reading surface by the reflecting surface formed on a part of the mounting base of the circuit board, the above-mentioned excellent optical characteristics and the structure are provided. It is possible to provide a simple and easy-to-manufacture LED light source device.

The reader and the reader-embedded device having the LED light source device of the present invention have the effects of the LED light source device, and can be easily manufactured as a whole.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of an LED light source device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the LED light source device according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining the operation of the LED light source device according to the first embodiment of the present invention.

FIG. 4 is a cross section of an LED light source device according to a second embodiment of the present invention.

FIG. 5 is a cross section of an LED light source device according to a third embodiment of the present invention.

FIG. 6 is a cross section of an LED light source device according to a fourth embodiment of the present invention.

FIG. 7 is a cross section of an LED light source device according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram showing a configuration of a reader-embedded device incorporating a reader having the LED light source device of the present invention.

FIG. 9 is a perspective view showing the appearance of a conventional LED light source device.

FIG. 10 is a cross-sectional view of a conventional LED light source device.

FIG. 11 is a diagram showing an operation of an LED light source device in which a condenser lens is installed at a correct position.

FIG. 12 shows L when the optical axes of the condenser lens and the LED are deviated from each other.
The figure which shows the effect | action of ED light source device.

FIG. 13 is a conventional L for facilitating position alignment of a condenser lens.
The perspective view which shows the external appearance of an ED light source device.

FIG. 14 is a conventional L for facilitating position alignment of a condenser lens.
FIG. 3 is a cross-sectional view of the ED light source device.

FIG. 15 is a conventional L for facilitating position alignment of a condenser lens.
The figure which showed the effect | action of ED light source device.

FIG. 16 is a perspective view showing the appearance of a conventional LED light source device having an LED structure.

FIG. 17 is a cross-sectional view of a conventional LED light source device having an LED structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LED light source device 2 Mounting base 3 Reflective surface 5 Circuit board 6 LED 9 Read original 81 Light receiving device 91 Reader built-in device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location G02B 27/00 J 7036-2K

Claims (6)

[Claims] 1. An LED light source device in which a circuit board on which a light emitting diode is mounted is mounted on a mounting base, wherein a part of the mounting base extends to a mounting surface of the light emitting diode of the circuit board and is arranged around the light emitting diode. An LED light source device having a light reflection surface. 2. The LED light source device according to claim 1, wherein the light reflecting surface of the mount is plated. 3. The LED light source device according to claim 1, wherein a tape made of resin that reflects light is attached to the light reflecting surface of the mounting base. 4. A transparent resin is filled in a recess formed by the light reflecting surface of the mounting base.
The LED light source device according to claim 3. 5. The LED light source device according to claim 1, an irradiation object for receiving light output from the device, and a light receiving device for receiving reflected light from the irradiation object. Reading device. 6. An apparatus incorporating a reading device, comprising: the reading device according to claim 5; and means for reproducing a read image.