JPH09120704A - Discharge lamp device and document irradiating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the document reading accuracy (resolution) by improving the illuminance on the surface of document sheet. SOLUTION: A pair of band-shaped external electrodes 4, 5 are isolatedly installed on the peripheral surface of a glass bulb 2 equipped with a light emitting surface 3 on the inner surface, and a rare gas is encapsulated in a glass bulb, and thus a rare gas discharge lamp 1 is formed. The arrangement further includes a lens assembly 6 of such a structure that a pair of legs 8, 9 are installed rigidly on a long stretching lens 7 having a light condensing function, and the lens 6 is mounted between the external electrodes at the peripheral surface of the discharge lamp in such an arrangement that the glass bulb 2 is pinched by the legs 8, 9, and thereby it is possible to condense the light from discharge lamp by the lens and heighten the illuminance of the document surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp device and a document irradiation device, and more particularly to a discharge lamp device and a document irradiation device for improving a document reading speed in OA equipment such as a facsimile, an image scanner, and a copy machine.

[0002]

2. Description of the Related Art A conventional document irradiating device of this type irradiates a document surface P with light emitted from a discharge lamp 1 and reflects light from the document surface P on a line formed by a CCD element, as shown in FIG. The sensor-S is configured to receive light.

As a discharge lamp applied to this device, it is required that the discharge lamp is also immediately turned on in accordance with the operation state of the device, and that its light amount reaches a predetermined light amount or more, for example, about 100% in a very short time. Have been.

Therefore, the applicant of the present invention has previously proposed a rare gas discharge lamp satisfying such requirements. As shown in FIG. 9, both ends of this discharge lamp are sealed, and the tube diameter is, for example, 5 to 1
A straight tube type glass bulb 2 of about 0 mm, and a light emitting layer 3 made of a phosphor formed on the inner surface of the glass bulb 2;
A pair of strip-shaped external electrodes 4, which are formed on the outer peripheral surface of the glass bulb 2 at appropriate intervals along the longitudinal direction thereof.
5, and a rare gas containing xenon gas as a main component is sealed in the sealed space inside the glass bulb.

In this discharge lamp 1, xenon gas is discharged by applying a high frequency high voltage (eg, 2500 Vp-p at 25 KHz) to the external electrodes 4 and 5, and the light emitting layer 3 is excited by the xenon gas excitation line (147 nm). Is excited to emit light, and light is emitted from the light emitting portion 2a between the external electrodes 4 and 5. In particular, since mercury is not used in this discharge lamp, the rise of the light amount after lighting is steep, the light amount reaches nearly 100% almost at the same time as lighting, and the light amount and the discharge voltage are affected by the ambient temperature. It has the characteristic that it receives almost no For this,
It sufficiently satisfies the above-mentioned requirements, and has recently attracted attention.

[0006]

The rare gas discharge lamp 1 described above is provided.
Is arranged in the document irradiation device shown in FIG. 8 so that the light emitting portion 2a faces the document surface P and the distance from the document surface P is about 6 to 12 mm. When the discharge lamp 1 is turned on, the illuminance on the document surface P is almost 200.
The value is about 00 (lx), and it is possible to reliably read the document.

When the illuminance on the document surface P is constant, the lower the document feeding speed, the better the reliability of reading the document. Conversely, the higher the feeding speed, the lower the reading accuracy (resolution). Tend to do.

However, in recent years, in order to improve the processing capability and improve the efficiency of office processing, the OA equipment tends to further increase the document feeding speed, which tends to impair the document reading accuracy. is there.

Therefore, in order to cope with the increase in the document feeding speed, the light output (light quantity) of the discharge lamp may be increased so as to increase the illuminance on the document surface P. For example, if the tube diameter of the discharge lamp 1 is made thicker than about 15 mm and the tube input (electric power) is increased, the light quantity can be relatively easily increased. Since the distance between the discharge lamps is as narrow as about 6 to 12 mm, it is difficult to dispose such a discharge lamp.

However, if the tube input of the current discharge lamp is increased without changing the size, the light quantity can be increased accordingly, but the increase rate of the light quantity is proportional to the increase of the tube input. However, the illuminance of the document surface cannot be obtained to the extent that sufficient reading accuracy is obtained.

Therefore, an object of the present invention is to increase the illuminance on the surface of a document with a relatively simple structure and to obtain a desired reading accuracy even if the document feed speed is high, and a document. An object is to provide an irradiation device.

[0012]

SUMMARY OF THE INVENTION Therefore, in order to achieve the above-mentioned object, according to the present invention, an elongated lens body having a condensing function is provided close to or in close contact with the outer peripheral surface of a straight tube discharge lamp. It is arranged.

According to a second aspect of the present invention, a pair of strip-shaped external electrodes are separately arranged on the outer peripheral surface of a glass bulb having a light emitting layer on the inner surface, and a rare gas is sealed in the glass bulb. Which comprises a rare gas discharge lamp and an elongated lens body having a light-collecting function, wherein the lens body is disposed close to or in close contact with the external electrodes on the outer peripheral surface of the rare gas discharge lamp. A third invention is a rare gas discharge lamp in which a pair of strip-shaped external electrodes are spaced apart from each other on the outer peripheral surface of a glass bulb having a light emitting layer on the inner surface, and a rare gas is enclosed in the glass bulb. A lens body formed by integrally forming a pair of leg portions on a long lens portion having an optical function, wherein a lens body is formed between the external electrodes on the outer peripheral surface of the rare gas discharge lamp, It is installed so that the glass bulb is sandwiched between the eggplant legs. .

Further, a fourth aspect of the present invention comprises a straight tube discharge lamp and a lens body formed by integrally forming a pair of leg portions with a long lens portion having a light collecting function. A lens body is attached to the outer peripheral surface of the discharge lamp so that the discharge lamp is sandwiched by a pair of legs.

Furthermore, a fifth aspect of the present invention is an original irradiating device which irradiates the original surface with light emitted from a discharge lamp and receives the reflected light with a sensor, which opposes the original surface of the discharge lamp. A sixth aspect of the present invention is characterized in that a long lens body having a light collecting function is arranged close to or in close contact with the outer peripheral surface of the discharge lamp, and the lens body is formed integrally with the discharge lamp. The invention is characterized in that the pair of legs is used for mounting, and the seventh aspect of the invention is to irradiate the original surface with light emitted from a discharge lamp supported by a pair of sockets and to use reflected light with a sensor. In the original irradiating device for receiving light, a long lens body having a light collecting function is attached to the pair of sockets so that the lens body is close to or in close contact with the outer peripheral surface of the discharge lamp facing the original surface. Characterize.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, one embodiment of the present invention will be described with reference to FIGS. The same parts as those of the conventional example shown in FIGS. 8 to 9 are designated by the same reference numerals, and detailed description thereof will be omitted. A feature of the present invention is that the elongated lens body 6 is mounted on the outer peripheral surface of the discharge lamp 1 so as to be close to or in close contact with the discharge lamp 1.

The lens body 6 is formed of, for example, polycarbonate or acrylic resin, and has a long lens portion 7 having a light-collecting function such as a convex lens, and both ends of the lens portion 7 on both sides. It is composed of a pair of claw-shaped legs 8 and 9 which are integrally formed. The lens body 6 is arranged on the outer peripheral surface of the discharge lamp 1 so that the lens portion 7 is located at the light emitting portion 2a between the external electrodes 4 and 5 of the discharge lamp, and further, forms a pair. The legs 8 and 9 are supported so as to sandwich the outer peripheral surface of the end portion of the glass bulb 2. In particular, when stable support is required, an adhesive or a tape can be used in combination for fixing. The legs 8,
The number of installations of 9 can be increased if necessary, and in some cases, they can be formed over the entire length of the lens portion 7.

According to this embodiment, since the lens body 6 is arranged in the light emitting portion 2a of the discharge lamp 1, the light emitted from the light emitting portion 2a is originally diffused. It is collected by the body 6. Therefore, the illuminance on the document surface can be greatly increased, and the document feeding speed of the OA device can be sufficiently increased.

Further, since the lens body 6 is thin, it can be easily applied to, for example, the discharge lamp shown in FIG. 8 without changing the specifications of the discharge lamp.

4 to 5 show different embodiments of the lens body according to the present invention. The lens body 6A shown in FIG. 4 is the discharge lamp side (light emitting portion side) of the lens portion 7.
Are formed in a flat shape, and the pair of leg portions 8 and 9 extending therefrom sandwich the glass bulb 2. Further, in the lens body 6B shown in FIG. 5, the discharge lamp side (light emitting portion side) of the lens portion 7 is also formed in a convex shape.

6 to 7 show a further different embodiment of the present invention. The discharge lamp 1 is a pair of sockets 1.
The ends of the discharge lamp 1 are mounted on the sockets 0 and 10 so as to be inserted into the recesses of the sockets 10 and 10. A lens body 6C is arranged close to or in close contact with the outer peripheral surface of the discharge lamp 1. In particular, the legs of the lens body 6C are omitted, and both ends thereof are fixed to the notches 11 and 11 formed in the sockets 10 and 10 with an adhesive or the like.
Incidentally, the lens body 6C can be fixed to the sockets 10 and 10 by using fitting or the like.

The present invention is not limited to the above-mentioned embodiment at all. For example, the discharge lamp may be a rare gas discharge lamp, or a general straight tube fluorescent lamp or a reflective fluorescent lamp. Further, the lens body can be fixed and arranged with respect to the discharge lamp by using the legs, and an adhesive, an adhesive tape, or the like can be used, or a member other than the discharge lamp can be used. Further, the lighting voltage and frequency of the discharge lamp can be set appropriately.

[0023]

EXAMPLE Next, an example of an experiment in which the discharge lamp device shown in FIGS. 1 to 3 is applied to the document irradiation device shown in FIG. 8 will be described. In this discharge lamp device, the rare gas discharge lamp has a tube diameter (outer diameter) of 8.5 mm, a total length of 350 mm, and a xenon gas filling pressure of 70 torr.
The distance between and is set to 8 mm. In this state, high frequency high voltage (29KH) is applied to the external electrode of the rare gas discharge lamp.
z, 2700 Vo-p) was applied and the lamp was turned on with a power consumption of 12 W, the illuminance on the document surface P was 3OOOO.
It was (lx). In addition, it was 20000 (lx) in the state (conventional example) with the lens body removed.

[0024]

As described above, according to the present invention, since the lens body is arranged close to or in close contact with the outer peripheral surface of the discharge lamp, the light emitted from the discharge lamp is effective by the lens body. Is focused. Therefore, the illuminance on the document surface can be greatly increased, and the document feeding speed of the OA device can be sufficiently increased.

Further, since the lens body is thin,
It can be easily applied to the discharge lamp of the document irradiation device without changing the specifications of the discharge lamp.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a side view of FIG. 1;

FIG. 3 is a perspective view of a lens body according to the present invention.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing another embodiment of the lens body according to the present invention.

FIG. 6 is a side view showing a third embodiment of the present invention.

7 is a cross-sectional view taken along the line I-I of FIG.

FIG. 8 is a schematic view of a conventional document irradiation device.

FIG. 9 is a cross-sectional view of a discharge lamp used in a conventional document irradiation device.

[Explanation of symbols]

 P Document surface 1 Discharge lamp 2 Glass bulb 2a Light emitting part 3 Light emitting layer 4,5 External electrode 6,6A, 6B, 6C Lens body 7 Lens part 8, 9 Leg part 10 Socket 11 Notch part

Claims (7)

[Claims] 1. A discharge lamp device characterized in that an elongated lens body having a light-collecting function is arranged close to or in close contact with the outer peripheral surface of a straight tube discharge lamp. 2. A rare gas discharge lamp in which a pair of strip-shaped external electrodes are spaced apart from each other on the outer peripheral surface of a glass bulb having a light emitting layer on the inner surface, and a rare gas is sealed in the glass bulb.
A discharge lamp device, comprising: an elongated lens body having a light condensing function, wherein the lens body is arranged close to or in close contact between external electrodes on an outer peripheral surface of the rare gas discharge lamp. 3. A rare gas discharge lamp in which a pair of strip-shaped external electrodes are spaced apart from each other on the outer peripheral surface of a glass bulb having a light emitting layer on the inner surface, and a rare gas is sealed in the glass bulb.
And a lens body formed by integrally forming a pair of leg portions on a long lens portion having a light collecting function, wherein the lens body is provided between the external electrodes on the outer peripheral surface of the rare gas discharge lamp. The discharge lamp device is characterized in that the glass bulb is mounted so as to be sandwiched by the legs forming the. 4. An outer peripheral surface of the discharge lamp, comprising: a straight tube type discharge lamp; and a lens body integrally formed with a long lens portion having a condensing function and a pair of legs. Lens body,
A discharge lamp device characterized in that the discharge lamp is mounted so as to be sandwiched by a pair of legs. 5. A document surface is irradiated with radiant light from a discharge lamp,
In a document irradiation device that receives reflected light with a sensor,
An original irradiating device, wherein an elongated lens body having a light-collecting function is arranged close to or in close contact with an outer peripheral surface of the discharge lamp facing the original surface. 6. The document irradiating apparatus according to claim 5, wherein the lens body is attached to a discharge lamp by utilizing a pair of legs formed integrally with the lens body. 7. An original irradiating device in which light emitted from a discharge lamp supported by a pair of sockets is applied to a surface of an original and reflected light is received by a sensor. An original irradiating device, wherein a lengthy lens body is attached so that the lens body is close to or in close contact with the outer peripheral surface of the discharge lamp facing the original surface.