JPH11331505A - Transmissive original illuminator, original reader and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need of an inverter which generates a high frequency and a high voltage, and also to eliminate the factors which causes the increase of costs such as a shield for a noise countermeasure and insulation for a human safety counter measure by using a solid light source to the light source of a transmissive original illuminator. SOLUTION: An LED 210 is placed on one of both end faces set in the longitudinal direction of a light guide 220 consisting of a light transmissive member having its different sectional areas between a position near the LED 210 and a position separated from the LED 210. Then a sawtooth part 222 is provided on a face opposite to an outgoing face 221 to reflect or scatter/luminous flux to the luminous flux of the guide 200. It's possible to make the luminous flux constant to be made incident on the part 222 and to obtain uniform illuminance characteristics by reducing the sectional area of the guide 220 as it is separated from the LED 210. A return face 223 in which a metal such as aluminum is vapor-deposited on the surface of the termination part of the guide 200 itself to reflect and return the luminous flux that propagates in the guide 220, is provided on the end face opposite to the end face where the LED 220 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a illuminating device for a transparent original, an original reading device having the illuminating device for a transparent original, and an information processing apparatus.

[0002]

2. Description of the Related Art There is a flatbed scanner for inputting an original such as a printed matter or a photograph into a computer.

As a specific configuration, as shown in FIG. 17, a photoelectric conversion element 311 such as a CCD line sensor is used.
And a fluorescent lamp 340 as a light source for illuminating the reflective original, and a mirror 350 that folds the reflected or transmitted light of the original.
The image sensor 300 includes a reduction lens 360 for forming an image of the light on the photoelectric conversion element 311, and a transmissive original illumination device 200 having a fluorescent lamp 215 as a light source for the transmissive original. The light focused on the photoelectric conversion unit is converted into an electric signal and transferred to a computer as image data.

Further, in the case of a scanner for reading a color original, a color filter is provided on the CCD image pickup device for separating the light into R, G, and B lights.

When reading a reflection original, the original is illuminated by the fluorescent lamp 340 of the image sensor 300 while scanning the image sensor 300, and the entire original is read.

When reading a transparent original such as an OHP sheet or a film, the image sensor 300 and the illuminating device for transparent original 200 are scanned in synchronization with each other, and the original is illuminated by the fluorescent lamp 215 of the illuminating device for transparent original 200. And
Scan the entire manuscript.

[0007]

However, in such a conventional example, since a fluorescent lamp is used as the light source for the transparent original, an inverter for generating a high-frequency high voltage is required to light the fluorescent lamp. Shielding of measures and insulation of human safety measures were the causes of cost increase.

[0008] In addition, the fluorescent lamp consumes a large amount of power, so that the interface for connecting to a computer is limited.
It was difficult to deal with the following assumptions.

Further, in a reading apparatus such as a flatbed scanner using the illuminating device for a transparent original, the image sensor and the illuminating device for a transparent original are configured as separate units, so that their relative positional relations are determined. It is required that the optical axis of the illuminating device for a transparent original be adjusted to the reading line of the photoelectric conversion element.

[0010] When illuminating with a reflective original illumination device,
When reading an original having a small thickness that transmits part of the light, the illuminating device for a transmissive original forms an image on an image sensor with a lens, or the illuminating device for a transmissive original simply reflects light. As a result, the optical information of the document may function as noise light, and good reading may not be performed.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems.

In other words, the illumination device for a transparent original according to the present invention is characterized in that a solid-state light source is used as a light source of the illumination device for a transparent original in a transparent original illumination device for illuminating the original with a transparent illumination.

The illumination device for a transparent original according to the present invention is the illumination device for a transparent original according to the above, wherein the light source is an LED,
Alternatively, EL is used.

Further, in the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original described above, a plurality of light sources having different emission wavelengths are used as the light source.

Further, in the illuminating device for a transparent original according to the present invention, in the illuminating device for a transparent original described above, a plurality of light sources having different emission wavelengths are used as the light sources, each of which can be turned on independently.

Further, in the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original described above, the illumination device for a transparent original is arranged so as to irradiate the original with light from an oblique direction.

Further, in the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original described above, the illumination device for a transparent original irradiates the original with light once from an oblique direction,
While the light reaches the document, there is provided a means for angle-converting the light so that at least a part of the light is irradiated perpendicularly to the document.

In the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original, a prism sheet, a light diffusing member, or a prism sheet and a light diffusing member may be provided at a light emitting portion of the illumination device for a transparent original. , Are provided.

Further, in the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original described above, a prism sheet and a light diffusing member are provided at a light emitting portion of the illumination device for a transparent original.
A prism sheet and a light diffusing member are provided at a light emitting portion of the illuminating device for a transparent document, and a light transmissive member is provided between the prism sheet and the light diffusing member. Is provided.

Further, in the illumination device for a transparent original according to the present invention, in the illumination device for a transparent original described above, the illumination device for a transparent original has the light source and a light incident surface, and is different from the light incident surface. A light diffusing region for reflecting and / or diffusing a light beam incident on one surface in the longitudinal direction of the light emitting device, and a light guide including a light transmitting member having an emission surface for emitting the reflected and / or diffused light. It becomes. Further, the illuminating device for a transparent document includes a plurality of the light guides and the light source for causing light to enter each of the light guides.

According to the present invention, there is provided an original reading apparatus comprising: a sensor comprising a plurality of photoelectric conversion elements; a reflection original illuminating device for illuminating the original; and an image forming means for forming optical information of the original on the sensor. A document reading apparatus provided with an image sensor having an image sensor and a transmissive document illuminating device for illuminating the document in a transmissive manner, wherein each of the above-described transmissive document illuminating devices of the present invention is used.

According to a second aspect of the present invention, in the above-mentioned original reading apparatus, the illumination width on the original surface of the illuminating device for the transparent original is wider than the illumination width of the illuminating device for the reflective original of the image sensor. It is.

Further, in the original reading apparatus according to the present invention, in the above-described original reading apparatus, the illuminating device for a transparent original is arranged farther than a focal depth position of the image forming means of the image sensor.

In the document reading apparatus according to the present invention, in the above document reading apparatus, the illuminating device for the transparent document is arranged farther than the illumination depth position of the illuminating device for the reflecting document of the image sensor.

An information processing apparatus according to the present invention is an information processing apparatus using each of the above-described document reading apparatuses according to the present invention.

(Operation) According to the present invention, a solid-state light source such as an LED (Light Emitting Diode) or an EL (Electroluminescence) is used as a light source of a transmission type illumination device, so that a low voltage can be obtained. It can be turned on, eliminating the need for an inverter.

Further, by arranging the transmissive illumination device so that the light irradiates the document from an oblique direction,
The irradiation width to the original can be widened.

The transmissive illuminator irradiates the document with light once from an oblique direction, and irradiates the document with at least a part of the light vertically while the light reaches the document. By changing the angle using a light diffusing member or the like, it is possible to widen the irradiation width to the original and increase the amount of light that can be captured by the lens.

Also, a sensor composed of a plurality of photoelectric conversion elements, an illuminating device for a reflective original for illuminating the original, and an image forming means such as a lens for forming optical information of the original on the sensor are provided. And an illuminating device for a transmissive original for illuminating the original with a transmissive original, the illumination width of the illuminating device for the transmissive original on the original surface is the illumination of the illuminating device for the reflective original of the image sensor. When the width is wider than the width, the relative alignment between the image sensor and the illumination device for the transparent original can be simplified.

Further, the illuminating device for a transmissive original is disposed farther than the depth of focus of the image forming means of the image sensor, so that the image forming means forms the illuminating device for a transmissive original on a photoelectric conversion element. There is no image.

Further, by arranging the illuminating device for a transmissive document farther than the illumination depth position of the illuminating device for a reflective document of the image sensor, the reflected light from the illuminating device for a transmissive document affects image reading. Can be excluded.

[0032]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 is a sectional view for explaining a first embodiment of the illumination device for a transparent original according to the present invention.

In FIG. 1, reference numeral 210 denotes a light source LE.
D and 220 are light guides for guiding light from the LED 210 and emitting light in a desired direction in a line corresponding to the length of the document, and 230 is light for emitting light from the light guide 220. A diffusion sheet for diffusion; 240, a substrate for electrically connecting the leads of the LED 210;
0, a light guide plate 220, a diffusion sheet 230, and a frame for positioning and holding the substrate 240. These members constitute an illumination device for a transparent original.

Reference numeral 100 denotes a transparent original such as an OHP or a film; 360, a lens for forming an image of the transparent original;
Reference numeral 1 denotes a photoelectric conversion element that converts the formed light into an electric signal.

FIG. 2 shows the LED 2 of the illumination device for a transparent original.
10 is a perspective view showing the light guide body 10 and the light guide 220. FIG.

The illumination device for a transparent original according to the present embodiment is an LED
An LED 210 is arranged on one end surface in the longitudinal direction of a light guide 220 made of a light transmissive member having a different cross-sectional area between the vicinity of the light guide 210 and a position distant therefrom. A saw-tooth portion 222 is provided on a surface facing the surface to reflect or diffuse a light beam. In addition, LED2
By decreasing the cross-sectional area of the light guide 220 as the distance from the light source 10 increases, the luminous flux incident on the sawtooth portion 222 can be made substantially constant, and uniform illuminance characteristics can be obtained.

On the end face opposite to the end face on which the LED 210 is provided, the surface of the terminal end of the light guide 220 itself is coated with a metal such as aluminum in order to reflect and turn back the light flux propagated in the light guide 220. Surface 223 formed by vapor-depositing or applying a metallic gloss paint or a light-diffusing reflective paint.
Is provided.

When it is desired to increase the illuminance of the document surface, an LED
The LED 210 may be arranged in the longitudinal direction of the light guide 220 not only on one side of the end of the light guide but also on the LED without the folded surface 223 at the end of the light guide.

The LED 210 has three LEs that emit red (R), green (G), and blue (B) light having different wavelengths.
D elements 211, 212, and 213 are provided, and each of them can be turned on independently. R, G, B LED
The element can be turned on with DC4 (V) or less and current consumption of about 20 (mA), and can be driven with low power consumption.

FIG. 3 shows a state in which the light beam incident on the light guide propagates through the light guide. The light emitted from the LED 210 is normally repeatedly reflected by the inner surface of the light guide 220 to guide the light. The light propagates inside the body 220, reaches the turning surface, and then returns toward the LED element. Further, the light beam incident on the saw-tooth portion 222 during propagation is reflected by the saw-tooth portion 222 toward the illumination direction.

FIG. 4 shows the state of a light beam emitted from the light exit surface of the light guide 220. The light beam is emitted from an oblique direction to the document, and is arranged in the optical path from the light source to the document surface. The light is converted by the diffusion sheet 230 into a light including a light beam which is irradiated perpendicularly to the document. This is because, first, the light beam is emitted from an oblique direction, so that the irradiation width is widened as compared with the case of vertically irradiating, and a light beam that can enter the expected angle of the lens 360 to be imaged on the sensor by the diffusion sheet 230. It is a configuration for.

Thus, the optical axis of the illuminating device for transparent document and the reading line of the photoelectric conversion element 311 can be matched without adjusting the position of the illuminating device for transparent document.

Next, a method of manufacturing the illumination device for a transparent original will be described.

As shown in FIG. 2, the LED 210 is formed by packaging LED elements for emitting three colors of red, green, and blue, respectively, and is supplied with power through a lead 214 to emit a light beam. Has become.

The light guide 220 can be formed of a resin having excellent light transmittance such as an acrylic resin by an emission molding method or the like.

Further, in order to form the saw-tooth portion 222 which is a diffusion region, if the shape is provided in a mold for emission molding,
It is easily possible.

The reflection efficiency is increased by applying a specular ink to the saw-tooth portion 222, and the illuminance of the original surface can be increased. However, as a method for applying the same, silk printing, dandelion printing, or the like can provide a uniform coating. It can be formed stably with a film thickness. Here, silk printing is screen printing in which silk is printed on a frame, and dandelion printing is a method in which a printing pattern is formed on a metal plate, ink is squeezed there, transferred to a rubber pad, and printed.

The fixing of the LED 210 to the light guide 220 is as follows.
By inserting and caulking the pins of the light guide 220 into the holes formed in the LED 210, the positioning and fixing can be performed with high accuracy.

FIG. 5 shows another example of a light guide. As shown in FIG. 5, the same applies to the case where a diffusion paint 224 such as white ink is applied to the light guide 220 instead of the sawtooth portion. It is possible to have a function. By increasing the area of the diffusion paint 224 as the distance from the LED 210 increases, uniform illuminance characteristics can be obtained.

The reflection of the light beam on the surface of the diffusion paint 224 is uniformly diffused and reflected without any directivity. Therefore, by covering the light emitting frame other than the light emitting portion with a light-reflective frame 225, the original document can be reflected without loss of the light beam. The illuminance of the surface can be increased.

FIG. 6 shows a second embodiment of the illuminating device for a transmissive document according to the present invention, and FIG. 7 shows a state of a light beam emitted from the light emitting surface of the light guide, wherein a fine prism is used instead of a diffusion sheet. By providing the prism sheet 260 on which the image is formed, it is possible to more efficiently convert the light beam into a light beam that is perpendicularly incident on the document.

FIGS. 8A, 8B, and 8C show a third embodiment of the illuminating device for a transparent original according to the present invention. By using both the diffusion sheet 230 and the prism sheet 260 in combination, FIG. Thus, it is possible to obtain a illuminating device for a transparent original having characteristics of a desired irradiation angle and irradiation width with respect to the original.

FIG. 8A shows the case where the diffusion sheet 230 and the prism sheet 260 are arranged in this order under the light guide and the LED. FIG. 8B shows the prism sheet 260 and the diffusion sheet under the light guide and the LED. When the sheets 230 are arranged in this order, FIG.
(C) is a diffusion sheet 230 under the light guide and the LED,
The case where the transparent member 270 and the prism sheet 260 are arranged in this order is shown.

In particular, FIG. 8 (C) shows that the light beam is diffused by the diffusion sheet 230 and the light beam propagates through the transparent member 270 so that the irradiation width is widened. Although the conversion mechanism is used, an arbitrary irradiation width can be set by adjusting the distance of the transparent member 270.

The transparent member 270 is not always necessary, and may be a simple space if it can be configured. In addition, if there is enough illuminance, even if the prism sheet 260 is eliminated and the diffusion sheet 230 is provided on both surfaces of the transparent member 270, an arbitrary irradiation width can be set by adjusting the distance of the transparent member 270. Further, the same effect can be obtained by providing an uneven surface on both surfaces or one surface of the transparent member 270 instead of the diffusion sheet 230.

FIGS. 9A, 9B and 9C show a fourth embodiment of a transmission type illumination device according to the present invention. The set of a light guide and a light source is arranged in two rows in parallel. The illuminance can be increased while obtaining a wider irradiation width. FIG. 9A shows a case where the prism sheet 260 is arranged below the light guide and the LED arranged in parallel, and FIG. 9B shows the light guide and the LED.
9C, the diffusion sheet 230 and the transparent member 2 are disposed below the light guide and the LED.
70 and the prism sheet 260 are arranged in this order.

FIGS. 10A and 10B show a fifth embodiment of the transmissive illumination device of the present invention. In each of the embodiments described above,
The light emitted from the light guide 220 is emitted obliquely with respect to the document surface. However, it is not always necessary to do so, and it is of course possible to include a component perpendicular to the document surface.

In this embodiment, the light emitted from the light guide 220 includes a component perpendicular to the document surface. In FIG. 10A, the light guide 220 has a semi-cylindrical lens shape, and the light from the sawtooth portion is substantially perpendicular to the document surface. FIG. 10B shows the light guide 220.
Apply a diffusion paint 224 such as white ink to the upper center of the
The light from the diffusion paint 224 is radially emitted by covering the light guide 220 with a light-reflective frame 225 having an open portion facing the diffusion paint 224 so that light from the diffusion paint 224 can be emitted. (Including a component perpendicular to the document surface).

Although not shown in FIG. 10, also in this embodiment, a diffusion sheet 230, a prism sheet 260, a transparent member 270, and the like can be used as appropriate, as shown in FIGS. Of course, in this case, it goes without saying that there is an effect that the irradiation width of the document surface is widened and the angle is efficiently converted to an angle that can be taken in by the lens.

FIG. 11 shows a sixth embodiment of the illuminating device for a transparent original according to the present invention.
LED elements 211, 21 for emitting R, G, B light on 0
It can also be configured by mounting a plurality of arrays 2 and 213 in an array.

Although the LED has been used as the light source of the illuminating device for a transparent document described so far, the light source is a solid-state light source, and is not limited to the LED as long as the same effect can be obtained. For example, an organic EL is used as the light source. You may.

Next, a case where the illumination device for a transparent original according to the present invention is used in a flatbed scanner as an original reading device will be described with reference to the drawings.

FIG. 12 shows an example of the flatbed scanner according to the present invention. Here, reference numeral 200 denotes a transparent document illuminating device for illuminating a transparent document, 300 denotes an image sensor that converts optical information of the document into an electric signal, and 401 and 4.
Reference numeral 02 denotes a driving motor for scanning the image sensor 300 and the illumination device 200 for a transparent original, respectively.
Reference numerals 3 and 404 denote belts for scanning the image sensor 300 and the illuminating device 200 for a transparent original by driving motors 401 and 402, and reference numerals 405 and 406 denote glass for regulating the position of the original.

FIG. 13 is a perspective view of the image sensor 300. Reference numeral 310 denotes a sensor array configured by reading a linear photoelectric conversion element 311 and accurately arranging a plurality of linear elements corresponding to the length of a document on a sensor substrate 312 such as a glass epoxy material, and 330 denotes a plurality of lens elements. And a lens array 320 consisting of a reflection array and a sensor array 310, a lens array 33.
The image sensor 300 is constituted by the illumination device 320 for the reflection document and the reflection document.

L which is the light source of the illuminating device 320 for the reflective original
The ED and the light guide are the same as those used in the illumination device 200 for a transparent original.

However, here, the illumination device 200 for the transparent original is used.
The LED as the light source and the light guide plate are each arranged in two pairs in parallel, and the illumination width of the original surface is adjusted by the illumination device 320 (L
The ED and the light guide plate are wider.

As a result, the positioning of the image sensor 300 and the illuminating device 200 for a transparent original, which are manufactured as independent units, can be easily performed, and the cost can be reduced in the manufacturing process.

When reading a transparent original, the image sensor 300 and the transparent original illumination device 200 are scanned in synchronization with each other, and the original is illuminated by the transparent original illumination device 200 to read the entire original.

When reading a reflection original, the image sensor 3 is scanned while the image sensor 300 is being scanned.
The original is illuminated by the reflective original illumination device 320 at 00 and the entire original is read.

However, even a reflective original made of thin paper may transmit a part of the light radiated from the reflective original illuminating device 320. Lighting device 20
0 may form an image on the photoelectric conversion element 311 as extra information other than the original document, so that good reading may not be performed.

This problem can be solved by arranging the illuminating device 200 for a transparent original outside the depth of focus of the lens array 330.

FIG. 14 shows the depth of focus characteristics of the lens array 330 according to the present embodiment. When the upper surface of the glass 405 on the image sensor 300 is in focus,
5. The illumination device 200 for a transparent original is placed at a position where resolution of 150 (DPI) or more cannot be obtained, separated from the upper surface by 1 (mm) or more.
It is desirable to arrange.

In general, the depth of focus is shallower in a lens array than in a reduction type single lens,
Using a lens array as a lens is advantageous in reducing the size of the entire apparatus, since the distance from which 0 is separated can be reduced.

Further, the light emitted from the reflective original illuminating device 320 and reflected by the transmissive original illuminating device 200 may become stray light even if an image is not formed and affect reading.

FIG. 15 shows the illumination depth characteristics of the illuminating device 320 for reflecting originals.
(%) Or less, it was confirmed that when the illumination device 200 for transparent originals was arranged at a distance to a position of about 2 (mm) or more, the influence was hardly affected.

That is, the illuminance on the reading line is 5 times smaller than the illuminance on the focal plane of the lens.
It refers to the position of 0 (%).

FIG. 16 shows an example of an information processing apparatus constituted by using the flatbed scanner described in each of the above embodiments. An image reading apparatus 70 having a built-in flatbed scanner 72 is connected to a personal computer 80 to form a system. A configuration example in which read image information is transmitted to a computer or a network will be described.

In FIG. 16, reference numeral 71 denotes a CPU as first control means for controlling the entire image reading apparatus 70;
Reference numeral 2 denotes a flatbed scanner as a reading unit configured to convert an image of a document into an image signal, which includes the light source and the CCD line sensor described above, and 73 denotes an analog image signal output from the flatbed scanner 72 for analog adjustment such as gain adjustment. An analog signal processing circuit that performs processing.

Reference numeral 74 denotes an A / D converter for converting the output of the analog signal processing circuit 73 into a digital signal, and reference numeral 75 denotes a memory 76 which uses the output data of the A / D converter 74 for shading correction processing and gamma conversion. An image processing circuit 77 for performing image processing such as processing and scaling processing is an interface for outputting digital image data subjected to image processing by the image processing circuit 75 to the outside.

The interface 77 is, for example, an SCS
It is connected to a personal computer 80 according to a standard adopted by a personal computer such as I or Bi-Centronics.

These analog signal processing circuits 73, A /
The D converter 74, the image processing circuit 75, and the memory 76 constitute signal processing means. The personal computer 80, which is the second control means, is provided with a magneto-optical disk drive, a floppy disk drive, and the like as the external storage device or the auxiliary storage device 81. Reference numeral 82 denotes a display for displaying work on the personal computer 80, and reference numeral 83 denotes a mouse / keyboard for inputting commands and the like to the personal computer.

Reference numeral 84 denotes an interface for exchanging data, commands, and status information of the image reading device between the personal computer and the image reading device.

The personal computer 80 can input a reading instruction to the image reading device by using a mouse / keyboard 83.

When a reading instruction is input by the mouse / keyboard 83, the CPU 85 sends a reading command to the image reading device 70 via the interface 84.

The personal computer 80
Controls the image reading apparatus according to the control program information stored in the ROM 86.

The control program may be executed by the CPU 85 by reading a program stored in a storage medium such as a magneto-optical disk or a floppy disk loaded in the auxiliary storage device 81 into the personal computer 80.

As described above, by using the flatbed scanner 72 described above in the present apparatus, it becomes highly practical and valuable.

[0089]

As described above, by using a solid-state light source such as an LED or an EL as a light source of the illuminating device for a transparent original, it becomes possible to light it at DC 4 (V) or less, and the inverter can be used. It becomes unnecessary.

This eliminates the need for measures against noise around high-frequency, high-voltage wiring, and simplifies insulation treatment for human safety measures, resulting in cost reduction.

Further, since the solid-state light source is lit at low voltage and consumes low power, for example, when configured as a scanner, the interface with the computer is not limited, and especially the USB standard (which is becoming mainstream in the future) is used. Drive voltage: 5V, power consumption: 500m
A or less).

Further, by reducing the number of solid-state light sources by using a light guide, it is possible to make use of the characteristic of low power consumption, and it is possible to apply the present invention to a portable terminal or the like.

Further, by arranging the illuminating device for a transmissive original such that the light irradiates the oblique direction with respect to the original, the irradiation width to the original can be widened, and the illuminating device for a transmissive original at the time of manufacturing the device Positioning can be simplified and man-hours can be reduced.

The illuminating device for a transparent original illuminates the original once from an oblique direction, and irradiates the original with at least a part of the light vertically to the original while the light reaches the original. By converting the angle using a sheet, a light diffusing member, or the like, it is possible to widen the irradiation width of the document and increase the amount of light that can be captured by an imaging unit such as a lens.

An image comprising a sensor comprising a plurality of photoelectric conversion elements, an illumination device for a reflective original for illuminating the original, and an image forming means such as a lens for imaging optical information of the original on the sensor. In a document reading device including a sensor and a transparent document illuminating device for illuminating a document in a transmissive manner, the illumination width on the document surface of the transmissive document illuminating device should be wider than the illumination width of the reflecting document illuminating device of the image sensor. Thus, the relative alignment between the image sensor and the illumination device for a transparent original can be simplified.

Further, by arranging the flatbed scanner illuminating device for a transmission original farther than the depth of focus of the imaging means such as a lens of an image sensor, the imaging means does not form an image on the transmission illuminating device. Good image reading is possible.

Further, by arranging the illuminating device for a transmissive document farther than the illumination depth position of the reflection type light source of the image sensor, the light from the illuminating device for a transmissive document is not reflected by the illuminating device for a transmissive document. And better image reading.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an illumination device for a transparent document according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a light source and a light guide of the illuminating device for a transparent original according to the first embodiment of the present invention.

FIG. 3 is a detailed view of a light guide of the illuminating device for a transparent document according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram of a light beam emitted from a light guide of the illuminating device for a transparent document according to the first embodiment of the present invention.

5A and 5B are a cross-sectional view and a plan view of a light source and another light guide of the illumination device for a transparent document according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view of a transparent document illumination device according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram of a light beam emitted from a light guide of the illuminating device for a transparent document according to the second embodiment of the present invention.

FIG. 8 is a cross-sectional view of an illumination device for a transparent document according to a third embodiment of the present invention.

FIG. 9 is a cross-sectional view of a transparent document illumination device according to a fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view of a transparent document illumination device according to a fifth embodiment of the present invention.

FIG. 11 is a top view of a light source of a illuminating device for a transparent document according to a sixth embodiment of the present invention.

FIG. 12 is a sectional view of a flatbed scanner according to a seventh embodiment of the present invention.

FIG. 13 is a perspective view of an image sensor of a flatbed scanner according to a seventh embodiment of the present invention.

FIG. 14 is a diagram illustrating a depth of focus of a lens of a flatbed scanner according to a seventh embodiment of the present invention.

FIG. 15 is a diagram showing an illumination depth of a reflection original illumination device of a flatbed scanner according to a seventh embodiment of the present invention.

FIG. 16 is a block diagram illustrating an information processing apparatus configured using the flatbed scanner of the present invention.

FIG. 17 is an explanatory diagram of a flatbed scanner using a conventional transparent original illumination device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 original 200 transmissive original illumination device 210 LED 211 red LED element 212 green LED element 213 blue LED 214 lead 215 fluorescent lamp 220 light guide 221 emission surface 222 sawtooth portion 223 folded surface 224 diffused paint 225 light reflective frame 230 Diffusion sheet 240 Substrate 250 Frame 260 Prism sheet 270 Light transmitting member 300 Image sensor 310 Sensor array 311 Photoelectric conversion element 312 Sensor substrate 320 Reflector original illumination device 330 Lens array 340 Fluorescent lamp 350 Mirror 360 Reduction lens 401, 402 Drive motor 403, 404 Belt 405, 406 Glass 70 Image reading device 71 CPU 72 Flatbed scanner 73 Analog signal processing circuit 74 A / D converter 75 Image processing circuit 76 Memory 77 Interface 80 Personal computer 81 Auxiliary storage device 82 Display 83 Mouse / Keyboard 84 Interface 85 CPU 86 RAM

Claims (32)

[Claims] An illumination device for a transmissive original for illuminating an original with a transmissive original, wherein a solid light source is used as a light source of the illumination device for a transmissive original. 2. An LED as a light source of the illuminating device for a transparent document.
The illumination device for a transparent original according to claim 1, wherein the illumination device is used. 3. The illuminating device for a transparent original according to claim 1, wherein an EL is used as a light source of the illuminating device for a transparent original. 4. The illuminating device for a transmissive original according to claim 1, wherein the light source of the illuminating device for a transmissive original includes a plurality of light sources having different emission wavelengths. 5. The illuminating device for a transmissive original according to claim 1, wherein a light source of the illuminating device for a transmissive original includes a plurality of light sources having different emission wavelengths, each of which can be turned on independently. 6. The illuminating device for a transmissive original according to claim 1, wherein the illuminating device for a transmissive original is arranged so as to irradiate light to the original from an oblique direction. 7. The illuminating device for a transparent document irradiates the document with light once from an oblique direction, and irradiates the document with at least a part of the light vertically to the document while the light reaches the document. 2. The illuminating device for a transparent document according to claim 1, further comprising means for performing the angle conversion as described above. 8. The illuminating device for a transmissive document according to claim 1, wherein a prism sheet is provided in a light emitting portion of the illuminating device for a transmissive document. 9. The illuminating device for a transmissive original according to claim 1, wherein a light diffusing member is provided at a light emitting portion of the illuminating device for a transmissive original. 10. The illuminating device for a transmissive document according to claim 1, wherein a prism sheet and a light diffusing member are provided in a light emitting portion of the illuminating device for a transmissive document. 11. The illuminating device for a transmissive original according to claim 1, wherein a prism sheet and a light diffusing member are provided at a light emitting portion of the illuminating device for a transmissive original, and are disposed separately from each other. . 12. A light source for a transmissive original, comprising a prism sheet and a light diffusing member in a light emitting portion, and a light transmissive member provided between the prism sheet and the light diffusing member. The illumination device for a transparent original according to claim 1. 13. The illuminating device for a transmissive document, comprising the light source and a light incident surface, and a diffusion region for reflecting and / or diffusing a light beam incident on one surface in a longitudinal direction different from the light incident surface. 2. The illuminating device for a transparent original according to claim 1, comprising: a light guide made of a light transmitting member having an emission surface for emitting the reflected and / or diffused light. 14. The transparent document illuminating device according to claim 13, wherein the illuminating device for a transmissive document includes a plurality of the light guides and the light source for causing light to enter each of the light guides. Lighting equipment. 15. An image sensor having a sensor comprising a plurality of photoelectric conversion elements, an illuminating device for a reflective original for illuminating an original, and an image forming means for forming optical information of the original on the sensor. An original reading device comprising: a transparent original illuminating device for illuminating the original with a transparent light; wherein a solid light source is used as a light source of the transparent original illuminating device. 16. The light source of the illuminating device for a transparent original is LE.
The document reading apparatus according to claim 15, wherein D is used. 17. A light source for the illuminating device for a transparent document, wherein the light source is EL.
16. The document reading device according to claim 15, wherein the document reading device is used. 18. The document reading apparatus according to claim 15, wherein the light source of the illumination device for a transparent document includes a plurality of light sources having different emission wavelengths. 19. The document reading apparatus according to claim 15, wherein the light source of the illuminating device for a transparent document includes a plurality of light sources having different emission wavelengths, each of which can be turned on independently. 20. The document reading apparatus according to claim 15, wherein the illuminating device for a transparent document is arranged so as to irradiate the document with light in an oblique direction. 21. The transmissive original illumination device irradiates the original with light once from an oblique direction, and irradiates the original with at least a part of the light in the middle of the light reaching the original. 16. The document reading apparatus according to claim 15, further comprising: means for converting the angle. 22. The document reading apparatus according to claim 15, wherein a prism sheet is provided in a light emitting portion of the transmissive document illuminating device. 23. The document reading apparatus according to claim 15, wherein a light diffusing member is provided in a light emitting portion of the illuminating device for a transparent document. 24. The document reading apparatus according to claim 15, wherein a prism sheet and a light diffusing member are provided in a light emitting portion of the illumination device for a transparent document. 25. The original reading apparatus according to claim 15, wherein a prism sheet and a light diffusing member are provided at a light emitting portion of the transmissive original illuminating device, and are separated from each other. 26. A light source for a transmissive original, comprising a prism sheet and a light diffusing member provided at a light emitting portion, and a light transmissive member provided between the prism sheet and the light diffusing member. The document reading device according to claim 15, wherein 27. The transmissive original illuminating device includes the light source and a light incident surface, and a diffusion region that reflects and / or diffuses a light beam incident on one surface in a longitudinal direction different from the light incident surface. 16. The document reading apparatus according to claim 15, comprising: a light guide made of a light transmissive member having an emission surface for emitting reflected and / or diffused light. 28. The original reading apparatus according to claim 27, wherein said transmissive original illuminating device comprises a plurality of said light guides and said light source for causing light to enter each of said light guides. . 29. The document reading apparatus according to claim 15, wherein an illumination width of the transmissive original illumination device on the original surface is larger than an illumination width of the reflection original illumination device of the image sensor. 30. The document reading apparatus according to claim 15, wherein the illuminating device for a transparent document is disposed farther than a depth of focus position of the image forming means of the image sensor. 31. The document reading apparatus according to claim 15, wherein the illuminating device for a transmissive document is arranged farther than an illumination depth position of the illuminating device for the reflecting document of the image sensor. 32. An information processing apparatus using the document reading device according to claim 15.