JPH11234480A - Original lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an original lighting device that lights up an original with a high efficiency or a high illuminance. SOLUTION: In this original lighting device, a reflecting mirror 4 is placed at a position within the range of a read ray 6 reflected on an original 2 irradiated by a fluorescent light 1, an optical fiber bundle and a 2nd reflecting mirror 8 are placed on the same side as the fluorescent light 1 with respect to the range of the read ray 6 reflected from the original 2, and an etching heater for warming up the fluorescent light 1 is made as an integral part of the 2nd mirror 8 or as one of its component and is arranged close to the fluorescent light 1. Thus, luminous flux divergent from the fluorescent light 1 is caught to the utmost and led to the face of the original at a high efficiency to light the original at a high illuminance, and also the light quantity of the fluorescent light itself is reduced to reduce power consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a document illuminating device such as an image reading device that illuminates a document in a line by using a fluorescent lamp as a light source.

[0002]

2. Description of the Related Art Conventionally, a document illuminating device has been used as a means for illuminating a document in an input device of a printer and a computer. And high illuminance are being promoted.

However, since the amount of light of a fluorescent lamp is not enough to illuminate a document with high illuminance, a light beam emitted from the fluorescent lamp and diffused from the fluorescent lamp is collected in a necessary area of the document surface using a reflecting member or the like. Therefore, a document illuminating device that illuminates a document with high illuminance has been proposed in Japanese Patent Application Laid-Open No. Hei 9-120704.

[0004] A conventional document illumination device will be described below. FIG. 10 is a front view of a conventional document illumination device, and FIG. 11 is a perspective view of the document illumination device.

[0005] In FIGS. 10 and 11, reference numeral 1 denotes a straight tube type fluorescent lamp as a light source, 2 denotes an original, 3 denotes an original glass on which the original 2 is loaded, and 10 denotes a light beam emitted from the fluorescent lamp 1. A condenser lens 6 is an original 2 illuminated by a fluorescent lamp 1
It is the reading light beam reflected from. The reading light beam is guided to a photoelectric conversion element by, for example, an imaging lens, and the image of the document 2 is converted into an electric signal.

Here, the condenser lens 10 is used to
Are arranged on the same side as the fluorescent lamp 1 with respect to the range through which the light passes. Specifically, the condenser lens 10 is mounted above the fluorescent lamp 1, that is, at a position close to the original glass 3, such that the incident surface is in close contact with the cylindrical surface of the fluorescent lamp 1.

The operation of the conventional document illuminating device having the above-described configuration will be described below.

[0008] The fluorescent lamp 1 emits light from a cylindrical surface coated with a phosphor, and its light beam diverges in all directions. Here, the condenser lens 10 captures the light flux in the range of A, and
The light is emitted from the emission surface facing the document 2 by guiding the inside of the document 0 to irradiate the document 2. Only the light beam in the range A illuminates the document 2.

[0009]

However, the configuration of the above-mentioned conventional document illuminating device has the following problems.

From the above description of the operation of the conventional document illuminating apparatus, it can be seen that, out of the total luminous flux emitted from the fluorescent lamp 1, A
Is guided to the original 2 only. Moreover, the range of A is narrow with respect to the width of the light emitting surface of the fluorescent lamp 1, and there are many wasteful light fluxes. That is, of the total luminous flux emitted from the fluorescent lamp 1, the ratio of reaching the original 2 is low, that is, the efficiency of the fluorescent lamp 1 illuminating the original 2 is low, and the original 2
However, there is a problem that it is difficult to illuminate the light.

Further, in order to increase the illuminance of the document 2, it is necessary to increase the amount of light of the fluorescent lamp 1 itself, which leads to an increase in power consumption, which leads to an increase in size and cost of the apparatus. Was.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a document illuminating device capable of illuminating a document with high efficiency or high illuminance.

[0013]

According to the present invention, there is provided a document illuminating apparatus for illuminating a document in a line with a straight tube-type fluorescent lamp as a light source. Are arranged in combination with a light guide member for guiding a part of the light to the document and a reflecting member for reflecting a part of another light beam emitted from the fluorescent lamp to the document.

According to the present invention, the luminous flux emitted from the fluorescent lamp can be captured as much as possible and guided to the document surface with high efficiency, so that the document can be illuminated with high illuminance. Also, when a certain document surface illuminance is required, the amount of light of the fluorescent lamp itself can be reduced as compared with the related art, and power consumption can be reduced. As a result, the power supply capacity can be reduced, and the size and cost of the device can be reduced, and the environment can be protected.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a document illuminating device which includes a straight tube-type fluorescent lamp as a light source and illuminates a document in a line, wherein the luminous flux emitted by the fluorescent lamp is provided. Is a light guide member that guides a part of the light to the document, and a reflection member that reflects a part of another light beam emitted by the fluorescent lamp to the document, and captures as much as possible the light beam emitted by the fluorescent lamp. And can be guided to the manuscript surface with high efficiency,
This has the effect that document illumination with high illuminance becomes possible. Further, when a certain document surface illuminance is required, it is possible to reduce the amount of light of the fluorescent lamp itself, to reduce the power consumption, thereby reducing the power supply capacity. This has the effect of enabling downsizing, cost reduction, and environmental protection.

According to a second aspect of the present invention, in the document illuminating apparatus according to the first aspect, the light guide member is constituted by a bundle of optical fibers, and the luminous flux emitted from the fluorescent lamp is captured as much as possible. Since the document can be guided to the document surface with high efficiency, the document can be illuminated with high illuminance.

According to a third aspect of the present invention, in the document illuminating apparatus according to the first aspect, the light guide member is constituted by a light guide, and the light flux emitted from the fluorescent lamp is captured as much as possible. Since the document can be guided to the document surface with high efficiency, the document can be illuminated with high illuminance.

According to a fourth aspect of the present invention, in the document illuminating device according to any one of the first to third aspects, a reading light beam reflected from a document illuminated with respect to a fluorescent lamp through a reflecting member passes. The light guide member is arranged on the same side as the fluorescent lamp with respect to the range through which the reading light beam reflected from the illuminated document passes, and the luminous flux emitted by the fluorescent lamp is possible. As long as it is possible to capture as much as possible and to guide the document surface more efficiently, it is possible to increase the illuminance of the document surface. Further, when a certain document surface illuminance is required, it is possible to reduce the amount of light of the fluorescent lamp itself, to reduce the power consumption, thereby reducing the power supply capacity. This has the effect of enabling downsizing, cost reduction, and environmental protection.

According to a fifth aspect of the present invention, in the document illuminating apparatus according to the fourth aspect, the second illuminating device is different from the reflecting member.
The reflection member is arranged with the light guide member on the same side as the fluorescent lamp with respect to the range where the reading light beam reflected from the illuminated document passes, and captures as much as possible the luminous flux emitted by the fluorescent lamp, Since the document surface can be more efficiently guided to the document surface, the illuminance of the document surface can be increased. Further, when a certain document surface illuminance is required, it is possible to reduce the amount of light of the fluorescent lamp itself, to reduce the power consumption, thereby reducing the power supply capacity. This has the effect of enabling downsizing, cost reduction, and environmental protection.

According to a sixth aspect of the present invention, in the document illuminating apparatus according to the fifth aspect, a heater for heating the fluorescent lamp is integrated with the second reflecting member or as one of components of the reflecting member. In addition, since the document illuminating device is arranged in close contact with the fluorescent lamp and the configuration of the document illuminating device can be simplified, it is possible to reduce the size and cost of the device.

According to a seventh aspect of the present invention, in the document illuminating apparatus according to the sixth aspect, the heater for heating the fluorescent lamp is an etching heater using stainless steel or aluminum, and the heater is a reflection member. Since it also has a role, it is possible to increase the efficiency of capturing the luminous flux emitted from the fluorescent lamp as much as possible and guiding it to the document surface, and to illuminate the document with high illuminance. Further, since the configuration of the document illuminating device can be simplified, there is an effect that the device can be reduced in size and cost can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 is a front view of a document illuminating device according to Embodiment 1 of the present invention, FIG. 2 is a perspective view of the document illuminating device, and FIG.
4 is an explanatory diagram of the operation of the original illuminating device, and FIG. 4 is an explanatory diagram of the illuminance distribution of the original surface by the original illuminating device. The same components as those in the above-described conventional example are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes a straight tube fluorescent lamp as a light source, 2 denotes an original, 3 denotes an original glass on which the original 2 is mounted, and 6 denotes a reading light beam reflected from the original 2 illuminated by the fluorescent lamp 1. These have the same configuration as the conventional example, and the description thereof will be omitted.

The first embodiment is characterized in that a reflecting mirror 4 for reflecting a light beam emitted from the fluorescent lamp 1 and a fluorescent lamp 1
The optical fiber bundle 5 for guiding the light beam emitted from the optical fiber is provided.

Here, the reflecting mirror 4 is disposed at a position sandwiching the range through which the reading light beam 6 passes with respect to the fluorescent lamp 1,
The optical fiber bundle 5 is attached to the upper side of the fluorescent lamp 1, that is, a position close to the original glass 3, such that the incident surface is in close contact with the cylindrical surface of the fluorescent lamp 1.

Next, the operation of the thus configured document illuminating device will be described with reference to FIG.

As shown in FIG. 3, the fluorescent lamp 1 emits light from the cylindrical surface on which the phosphor is applied, and the emitted light flux diverges in all directions. Here, the reflection mirror 4 captures the light flux in the range A among the light fluxes diverged and diverged from the fluorescent lamp 1 and reflects the light flux toward the document 2.

The optical fiber bundle 5 captures the light beam in the range B from the incident surface in contact with the cylindrical surface of the fluorescent lamp 1, guides the inside of the optical fiber bundle 5 and emits the light from the exit surface facing the document 2, Irradiate toward.

The luminous flux emitted from the fluorescent lamp 1 in the range C other than the ranges A and B described above directly reaches the document 2. The light flux in the range from A to C illuminates the document 2.

FIG. 4 shows the illuminance distribution on the document 2 obtained by the above configuration. The solid line is the illuminance distribution of the original 2 obtained by the original illuminating device of the first embodiment, and the dotted line is the illuminance distribution on the original 2 according to the above-described conventional configuration. From this result, it can be seen that a wide range of luminous fluxes from A to C emitted from the fluorescent lamp 1 is guided to the original 2, and the illuminance on the surface of the original 2 is increased.

By the above operation, the luminous flux emitted from the fluorescent lamp can be captured as much as possible and guided to the original surface more efficiently, so that the illuminance of the original surface can be increased. Also, when a certain document surface illuminance is required, the amount of light of the fluorescent lamp itself can be reduced as compared with the related art, and power consumption can be reduced. As a result, the power supply capacity can be reduced, and the size and cost of the device can be reduced, and the environment can be protected.

In the first embodiment of the present invention, the light guide member is constituted by an optical fiber bundle. However, the same effect can be obtained by replacing the light guide member with a light guide.

(Embodiment 2) FIG. 5 is a front view of a document illuminating device according to a second embodiment of the present invention, FIG. 6 is a perspective view of the document illuminating device, and FIG. 7 is a configuration of an etching heater in the document illuminating device. FIG. 8 is a diagram for explaining the operation of the original illuminating device, and FIG.
FIG. 4 is an explanatory diagram of an illuminance distribution of a document surface by the document illuminating device.

In the drawing, 1 is a fluorescent lamp, 2 is a document, 3 is a document glass, 4 is a reflection mirror, 6 is a reading light beam,
Since these have the same configuration as the first embodiment, their description will be omitted.

The second embodiment is characterized in that the light guide 7 for guiding the light beam emitted from the fluorescent lamp 1, the second reflecting mirror 8 different from the reflecting mirror 4, and the fluorescent lamp 1 are heated. And an etching heater 9 using stainless steel or aluminum. As shown in FIG. 7, the etching heater 7 has an X portion which is a surface etched from stainless steel or aluminum, and a Y portion which is a sheet member serving as a base material. Is made of transparent material.

Here, the reflecting mirror 4 is the same as that of the first embodiment.
Similarly, the light guide 7 and the second light guide 7
Are combined on the same side as the fluorescent lamp 1 with respect to the range through which the reading light beam 6 passes. Specifically, the light guide 7 is attached to the upper side of the fluorescent lamp 1, that is, a position close to the original glass 3 so that the incident surface is closely attached to the cylindrical surface of the fluorescent lamp 1. , That is, a position far from the document glass 3. The etching heater 9 is integrated with the second reflection mirror 8, and is closely attached to the reflection mirror 4, the light guide 7, or the cylindrical surface of the fluorescent lamp 1 in a range that does not block the light flux directly traveling to the original surface. Installed.

Next, the operation of the thus configured document illuminating device will be described with reference to FIG.

The fluorescent lamp 1 emits light from the cylindrical surface on which the phosphor is applied, and the emitted light beam diverges in all directions. Here, the reflecting mirror 4 captures the light flux in the range A among the light fluxes emitted from the fluorescent lamp 1 and reflects the light flux toward the document surface.
Further, the light guide 7 catches the light flux in the range B from the incident surface in close contact with the cylindrical surface of the fluorescent lamp 1, guides the inside of the light guide 7, emits the light from the exit surface facing the document surface, and faces the document surface. And irradiate. The second reflecting mirror 8 catches the light flux in the range C and reflects it toward the original surface.

The etching heater 9 catches the light flux in the range of D and reflects it toward the original surface from the etched surface of stainless steel or aluminum having high reflectivity. However, since the reflected light passes through the fluorescent lamp 1 and is attenuated, the light flux actually reaching the document surface is about 30% of the light flux reflected by the etching heater 9. However, there is a sufficient effect to increase the illuminance on the document surface. Further, the luminous flux emitted from the fluorescent lamp 1 in the range E outside the range A to D described above directly reaches the document 2. The light fluxes in the range from A to E illuminate the document 2.

FIG. 9 shows the illuminance distribution on the document surface obtained by the above configuration. The solid line is the illuminance distribution on the original surface obtained by the original illuminating device according to the second embodiment, and the dotted line is the illuminance distribution on the original surface according to the conventional configuration. From this result, it can be seen that the luminous flux in the range from A to E emitted from the fluorescent lamp 1 is guided to the document 2, and the illuminance on the document surface is increased.

By the above operation, the luminous flux emitted from the fluorescent lamp can be captured as much as possible and guided to the original surface more efficiently, so that the illuminance of the original surface can be increased. Also, when a certain document surface illuminance is required, the amount of light of the fluorescent lamp itself can be reduced as compared with the related art, and power consumption can be reduced. As a result, the power supply capacity can be reduced, and the size and cost of the device can be reduced, and the environment can be protected.

In the second embodiment, the light guide member is constituted by a light guide. However, even if the light guide member is replaced by an optical fiber bundle, substantially the same effect can be obtained.

[0043]

As is apparent from the above description, according to the present invention, the luminous flux emitted from the fluorescent lamp can be captured as much as possible and guided to the document surface with high efficiency, so that the document illumination with high illuminance can be achieved. When a certain document surface illuminance is required, it is possible to reduce the amount of light of the fluorescent lamp itself, thereby reducing power consumption, thereby reducing the power supply capacity. It is possible to reduce the size and cost of the apparatus and to protect the environment, and the effect is great as a document illuminating apparatus.

[Brief description of the drawings]

FIG. 1 is a front view of a document illumination device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the document illumination device.

FIG. 3 is an explanatory diagram of the operation of the original illumination device.

FIG. 4 is an explanatory diagram of an original surface illuminance distribution by the original illuminating device.

FIG. 5 is a front view of a document illuminating device according to a second embodiment of the present invention;

FIG. 6 is a perspective view of the document illumination device.

FIG. 7 is a configuration diagram of an etching heater in the document illumination device.

FIG. 8 is a diagram illustrating the operation of the original illumination device.

FIG. 9 is an explanatory view of an original surface illuminance distribution by the original illuminating device.

FIG. 10 is a front view of a conventional document illumination device.

FIG. 11 is a perspective view of the document illumination device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fluorescent lamp 2 Document 3 Document glass 4 Reflection mirror 5 Optical fiber bundle 6 Reading light beam 7 Light guide 8 Second reflection mirror 9 Etching heater

Claims (7)

[Claims] 1. A document illuminating device comprising a straight tube-type fluorescent lamp as a light source and illuminating a document in a line, wherein a light guide member for guiding a part of a light beam emitted by the fluorescent lamp to the document is provided. A document illuminating device provided with a reflecting member for reflecting a part of another light beam emitted by a lamp to a document. 2. The original illuminating device according to claim 1, wherein the light guide member is an optical fiber bundle. 3. The original illuminating device according to claim 1, wherein the light guide member is a light guide. 4. A range in which a reading member passes through a range through which a reading light beam reflected from an original illuminated by a fluorescent lamp passes, and a light guide member passes through a reading light beam reflected from the illuminated original document. The document illuminating device according to any one of claims 1 to 3, wherein the document illuminating device is disposed on the same side as the fluorescent lamp. 5. A light guide member, wherein a second reflection member different from the reflection member is arranged on the same side as the fluorescent lamp with respect to a range through which a reading light beam reflected from the illuminated document passes. The document illumination device according to claim 4, wherein 6. A heater according to claim 5, wherein the heater for warming the fluorescent lamp is formed integrally with the second reflecting member or as one of components of the reflecting member, and is arranged in close contact with the fluorescent lamp. Document illumination device. 7. The original illuminating device according to claim 6, wherein the heater for warming the fluorescent lamp is an etching heater using stainless steel or aluminum.