JPH0317502Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field This invention is a reading method that reads the color information of a document by irradiating illumination light of multiple different colors onto the surface of the document and sequentially guiding the reflected light to a photoelectric conversion element. Regarding equipment.

BACKGROUND ART It has been well known that in color facsimile and the like, the color information of a document is read by a reading device of the above type. Conventional reading devices of this type typically use a plurality of light sources and illuminate the surface of the document with these light sources. However, if a plurality of light sources are used in this manner, the structure becomes complicated and the cost increases.

Purpose The purpose of the present invention is to provide a reading device that eliminates the above-mentioned conventional drawbacks.

Configuration In order to achieve the above object, the present invention provides a reading device that reads color information of a document by irradiating the surface of the document with illumination light of multiple different colors and sequentially guiding the reflected light to a photoelectric conversion element. a document conveying means for intermittently conveying the document; a sole light source having a coloring means disposed along its periphery for irradiating illumination light of the plurality of colors onto the document surface; and the document conveying means. The present invention proposes a reading device comprising driving means for rotationally driving the light source so that light from the coloring means is sequentially irradiated onto the surface of the document while the document is stopped.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The drawings show a specific example in which the present invention is applied to a color facsimile reading device.

The reading device 1 shown in FIGS. 1 and 2 is a fluorescent lamp 2.
Like conventional fluorescent lamps, this fluorescent lamp 2 has a cylindrical tube 3 made of transparent glass or the like, and mercury vapor is sealed inside the tube. The difference from conventional fluorescent lamps is that the inner surface of the tube 3 has a red phosphor 4, a green phosphor 5, and a blue phosphor, which are fluorescent substances that emit light of different colors, namely red, green, and blue, respectively. These are the points where the bodies 6 are respectively applied. These fluorescent bodies 4, 5, and 6 constitute an example of a coloring means for irradiating illumination light of multiple colors onto the document surface, and are arranged along the circumference of the light source consisting of the fluorescent lamp 2. It extends in the longitudinal direction of the tube 3 in a band shape.

As shown in FIG.
0, and one holder 9 has a pulley 11 attached thereto. This pulley 11 is drivingly connected to a motor 13 via a belt 12.
The motor 13 rotates the fluorescent lamp 2, for example, clockwise in FIG.

Reference numeral 14 in FIG. 1 is a document irradiated with light from the fluorescent lamp 2, 15 is an imaging element, and 16 is a photoelectric conversion element.
As is well known, the photoelectric conversion element 16 includes a large number of photoelectric conversion elements arranged in the longitudinal direction of the fluorescent lamp 2, that is, in the main scanning direction. As the imaging element, for example, an ordinary lens or a focusing rod lens can be used.

During the reading operation of the original image, the original 14 is moved in a direction perpendicular to the longitudinal direction of the fluorescent lamp 2, that is, in the sub-scanning direction indicated by arrow A, by an original transport means (not shown) that transports the original intermittently. Sent intermittently. Meanwhile, the fluorescent lamp 2 is turned on, and the fluorescent bodies 4, 5, and 6 are excited by ultraviolet rays from the mercury vapor in the tube 3, and emit red, green, and blue light, respectively. At that time, since the fluorescent lamp 2 is rotated by the motor 13,
The light from each of the phosphors 4, 5, and 6 sequentially illuminates the illuminated portion on the document surface, that is, the line-shaped portion 14a in the direction perpendicular to the plane of the paper in FIG. For example, if the red phosphor 4 first illuminates the linear portion 14a, then the rotation of the phosphor 2 causes the green phosphor 5 to face the linear portion 14a and emit the green light. is applied to the linear portion 14a, and then blue light from the blue phosphor 6 irradiates the linear portion 14a. When the original 14 is irradiated with light of three colors in this way, the document 14 has just stopped, so these lights illuminate the same linear portion 14a, and the light reflected here is reflected by the imaging element 1.
5, the light is imaged and focused on the photoelectric conversion element 16, and the element 16 outputs electrical signals corresponding to the brightness and darkness of each color image of the linear portion 14a in time series. By repeating this action,
The entire document image is read.

The above-described reading device 1 reads the color information of the document 14 by illuminating the surface of the document with illumination light of a plurality of different colors and sequentially guiding the reflected light to a photoelectric conversion element. Pulley 1
1. The belt 12 and the motor 13 are driving means for rotationally driving a light source so that the light from the coloring means is sequentially illuminated on the surface of the original when the original being transported by the original transporting means is stopped. This constitutes an example. According to such a configuration, color information of a color document can be read by using only one light source, and the reading device 1 can be configured compactly.

In the embodiment shown in FIG. 1, the coloring means consisting of the phosphors 4, 5, and 6 was made to emit light by ultraviolet excitation, but in the embodiment shown in FIG. It is configured to emit light using electrons.

The reading device 1a shown in FIG. 3 has a sole light source consisting of a so-called thermionic-excited fluorescent tube 2a, and this fluorescent tube 2a has a rectangular cross section that extends perpendicularly to the plane of the paper. It has a rectangular parallelepiped sealed container 3a, and the inside of the container 3a is kept in vacuum. The four side plates 17, 18, 19, 20 constituting the container 3a are made of a transparent material, for example transparent glass, and two end wall plates 21 (only one of which is shown in FIG. 3) are located at each end of these side plates. is preferably formed to be opaque.

On the inner surface of one side plate 17, a slit-shaped transparent part 22 is opened in the center, and two first anode electrodes 23 extending in the longitudinal direction of the container 3a are provided. A light body 4a is applied.
In exactly the same way, second and third anode electrodes 26, 27, a green phosphor 5a, and a blue phosphor 6a are provided on the inner surfaces of the other two side plates 18, 19 with the transparent parts 24, 25 in between.
are provided as shown in the figure. The anode electrodes 23, 26, 27 in this example are made of transparent material.

A suitable number of thermionic generation sources formed as filaments 28 extending in the longitudinal direction of the container 3a are arranged inside the container 3a, and each phosphor 4a, 5a, 6
A grid electrode can also be provided between a and the filament 28. The anode electrodes 23, 26, 27 and filament 28 are connected to a power source outside the container. The fluorescent tube 2a is rotated clockwise in FIG. 3 by a driving means comprising a motor 13, a belt 12, etc., just like the fluorescent lamp 2 shown in FIG.

When reading a document image, for example, the red phosphor 4a is illuminated by a line-shaped portion 14a of the document 14, as shown in FIG.
to face first. At this time, a current is passed through the filament 28, and thermoelectrons are thereby emitted from the filament. On the other hand, a positive voltage is applied to the first anode electrode 23, and the thermoelectrons collide with the red phosphor 4a. Therefore, the red phosphor 4a emits red light,
This red light passes through the transparent anode electrode 23 and the side plate 17, and illuminates the line-shaped portion 14a of the document 14, which is just stopped at this time. The light reflected here passes through the transparent part 22 of the side plate 17 again, and the light reflected on the side plate 17
The liquid passes through the light-transmitting part 25 of the side plate 19 located opposite to the side plate 19 and exits the container. Thereafter, as in the case of FIG. 1, the light is focused by the imaging element 15 onto the photoelectric conversion element 16, and the element 16 outputs an electric signal.
When such an operation is performed, it is desirable that no voltage is applied to the second and third anode electrodes 26 and 27 so that light other than red does not hit the surface of the document.

Next, the fluorescent tube 2a is rotated by the motor 13, so that the green fluorescent material 5a faces the linear portion 14a as shown in FIG. Then, a positive voltage is applied to the second anode electrode 26, and the green light from the green phosphor 5a is transmitted to the linear portion 1 in exactly the same manner as the red phosphor 4a.
4a, and the reflected light passes through the side plate 20 and reaches the photoelectric conversion element 16. Next, the light from the blue phosphor 6a is guided to the photoelectric conversion element 16 in exactly the same manner. In this way, the line-shaped portion 14 of the original 14 is
A is irradiated with three colors of light, and a predetermined document image is read.

In the embodiment shown in FIGS. 3 and 4, the light emitted from the container 3a is guided to the imaging element 15 through the slit 30 of the slit member 29, but this is not necessary. This is to prevent light other than the light from reaching the photoelectric conversion element 16, and depending on the case, this slit member may be omitted. For example, if the entire side plate 20 is not made transparent, but only the light-transmitting portion 31 through which effective light reflected from the document surface is made transparent, and the other portions are made opaque, unnecessary light will pass through the side plate 20 through the imaging element. The slit member 29 can be omitted without any problem.

In the embodiment shown in FIG. 5, the container 3a is formed into a triangular prism shape, and each side plate 17, 18,
Anode electrodes 23, 26, 27 and red, green,
Blue phosphors 4a, 5a, and 6a are provided, respectively,
The original 1 is emitted from each phosphor 4a, 5a, 6a.
The light reflected by the slit-like portion 14a of No. 4 directly reaches the imaging element 15, and other points are essentially different from the embodiment shown in FIGS. 3 and 4. There is no place. In this embodiment as well, it is of course possible to use the slit member shown in FIG.

As mentioned above, the reading device 1a shown in FIGS. 3 to 5 also irradiates the document surface with illumination light of a plurality of different colors, and sequentially guides the reflected light to the photoelectric conversion element 16, thereby reading the document. 14 color information can be read. At that time, this reading device 1a
Also, a phosphor 4 for emitting illumination light of multiple colors.
The light source has a single light source with a coloring means formed by A, 5a, and 6a arranged around the periphery thereof, and a driving means for rotationally driving the light source as in the embodiment shown in FIG.

Although the advantageous embodiments of the present invention have been described above, the structure of the present invention can be modified in various ways. for example,
In the illustrated embodiment, three coloring means that emit light of different colors are provided, and the light source is configured to emit three types of light. It is sufficient to simply provide a coloring means. It is also natural that, instead of using a motor, belt, pulley, etc., other suitable devices may be used as the driving means for integrally rotating the plurality of coloring means. Furthermore, the illumination reading device according to the present invention can also be used in a case where the emitted light is guided not by an imaging element but by a light guide means such as an optical fiber, and the reading device according to the present invention can be used in a document image reading device of a digital copying machine. It can also be advantageously used.

Effects According to the present invention, color information on a document can be read by using only one light source.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view showing an example of a reading device according to the present invention, FIG. 2 is a side view of FIG. 1 with some of the components shown in FIG. 1 omitted, and FIG.
The figure is a partially sectional front view similar to FIG. 1 showing another embodiment, FIG. 4 is a partially sectional front view showing a state in which the light source is rotated from the state shown in FIG. 3, and FIG. 5 is a still another embodiment. This is a partial cross-sectional front view similar to FIG. 3 showing an example, and in FIGS. 1 and 3 to 5, hatching is omitted in the cross section of transparent parts to make the figures easier to understand. be. 1...Reading device, 14...Document, 16...Photoelectric conversion element.

Claims (1)

[Claims for Utility Model Registration] (1) A reading device that reads color information on a document by illuminating the surface of the document with illumination light of multiple different colors and sequentially guiding the reflected light to a photoelectric conversion element. A document transport means for intermittently transporting a document; a sole light source having a coloring means for irradiating the illumination light of the plurality of colors onto the document surface along its periphery; and driving means for rotationally driving the light source so that the light from the coloring means is sequentially irradiated onto the surface of the document while the document is stopped. (2) The reading device according to claim 1, wherein the coloring means emits light by excitation with ultraviolet light. (3) The reading device according to claim 1, wherein the coloring means is caused to emit light by slow thermionic electrons from a thermionic source.