JPH059721Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial field of application) The present invention relates to an exposure device for an electrostatic recording device, and more specifically, a tube-shaped exposure device that is arranged in the width direction of an original, and a part of the emitted light is directed directly toward the original. a light source, and a first reflector supported by a support member so as to be arranged parallel to the light source at a constant interval, and which receives light that is not directed directly toward the document from the light source and reflects it toward the document. The present invention relates to an exposure apparatus that includes a member, and that allows light reflected from a document to pass between the first reflective member and the light source and converges on a photoreceptor via a lens.

(Background of the idea) When the manuscript placed on the platen glass is made of original paper with pieces of paper pasted on it, there will be a step between the original paper and the pasted paper pieces, so if light is applied from only one direction, A shadow may be formed on the step further away from the light source and may be recorded as a black line. In order to prevent this, there is an exposure device that is provided with a reflective member that directs the light beam from the light source toward the document with a lens in between, so that shadows are not formed even on the stepped portions farther from the light source. It is said that the ratio of the amount of reflected light (reflection member) to direct light (light source) is preferably 6:4 to 7:3. In such exposure equipment, when a fluorescent lamp is used as a light source, the amount of light at both ends of the fluorescent lamp is lower than that at the center, and the amount of light irradiated onto the document is larger at the center and less at both ends. It becomes less. Therefore, by providing another light source at the end,
Reduce the light intensity in the center of the fluorescent lamp itself,
In addition, a light distribution regulating plate is provided so that the amount of light irradiated onto the document remains constant in the width direction of the document.

(Problems to be solved by the invention) However, it is necessary to provide another light source at the end of the above structure, reduce the light intensity at the center of the fluorescent lamp itself,
Further, an exposure apparatus provided with a light distribution regulating plate has problems in that it requires a large number of parts and a large number of assembly steps, is costly, and is difficult to downsize.

This invention was made in view of the above problems,
The purpose is to provide a compact exposure device at a low cost, in which the amount of light irradiated onto a document in the width direction is almost constant, and the number of parts and assembly steps are small.

(Means for Solving the Problems) The present invention which solves the above problems consists of a tubular light source arranged in the width direction of the document, and a part of the emitted light directed directly toward the document; a first reflecting member that is supported by a supporting member so as to be arranged in parallel with the light source, receives light that is not directed directly toward the original from the light source, and reflects the light toward the original;
In an exposure device that passes reflected light from a document between the first reflective member and the light source and focuses it onto the photoreceptor via a lens, , a first position on the support member close to the lens, and a second position on the support member near the end of the first reflection member and close to the lens. The present invention is characterized in that a second reflective member whose reflective surface faces the original is provided only at position 2.

(Function) The original is irradiated with light by direct light from the light source and reflected light from the first reflecting member, and the reflected light from the original is focused onto the photoreceptor via the lens.
A second reflective member is provided near the end of the first reflective member and close to the lens, so that the light receiving surface of the lens is reflected from the original toward the lens. A portion of the stray light enters the second reflecting member and is reflected back toward the document. Therefore, the edges of the document in the width direction are irradiated with not only direct light from the light source and reflected light from the first reflecting member, but also light reflected from the second reflecting member. The amount of light can be made constant.

(Example) Next, an example of the present invention will be described with reference to FIGS. 1 to 3.

In these figures, 1 is an exposure device, and 2 is an original table glass that moves on the exposure device 1. Reference numeral 3 denotes a light source, which in this embodiment is an aperture type fluorescent lamp having an aperture portion 3a extending over the entire width and having a tube length longer than the image width D. The light emitted from the aperture portion 3a is designed to illuminate the original 4 on the original platen glass 2. And manuscript 4
The reflected light is focused onto the photosensitive drum 6 by a lens, in this embodiment, a gradient index lens (for example, a self-locking lens array) 5. As shown in FIG. 2, the gradient index lens 5 is disposed between bridging members 7a and 7b that bridge the side plates of the exposure apparatus 1 via light shielding members 8a and 8b. Also, among the light emitted from the aperture section 3a, the light that does not illuminate the original 4 is transmitted to a first reflecting member disposed opposite the aperture section 3a with the gradient index lens 5 in between. The light is reflected by the first reflecting mirror 9 and illuminates the original 4. A shutter 10 is provided between the gradient index lens 5 and the photoreceptor drum 6, and when not exposed, the shutter 10 is at the position indicated by the two-dot chain line in FIG. It is designed to block the optical path to. This is because, in this embodiment, in order to stabilize the amount of light, the aperture type fluorescent lamp 3 is turned on continuously even during non-exposure, so the photoreceptor drum 6 is exposed to unnecessary light. This is to prevent fatigue.

And near the end of the first reflecting mirror 9,
At a position close to the gradient index lens 5, a second reflecting member whose reflecting surface faces the original 4, in this embodiment, second reflecting mirrors 11a and 11b, is provided. As is clear from FIG. 4, the first reflecting mirror 9 and the second reflecting mirrors 11a and 11b are
It is provided on the inclined surface and the upper bottom surface of the bridging member 7b, which is a supporting member.

Next, the operation of the above configuration will be explained. A portion of the light emitted from the aperture portion 3a of the aperture type fluorescent lamp 3 is irradiated directly onto the original 4, and a portion is reflected by the first reflecting mirror 9 and irradiated onto the original 4. Further, the reflected light from the original document 4 is focused onto the photosensitive drum 6 via the gradient index lens 5 .
A second reflecting mirror 11 is located near the end of the first reflecting mirror 9 and close to the gradient index lens 5.
a, 11b are provided, of the reflected light that has come from the document 4 toward the gradient index lens 5,
A part of the light that deviates from the light receiving surface of the gradient index lens 5 enters the second reflecting mirrors 11a and 11b,
It is reflected again toward the original document 4. Therefore, manuscript 4
At the end in the width direction, not only the direct light from the fluorescent lamp 3 and the reflected light from the first reflecting mirror 9 but also the second
It is irradiated with light reflected from the reflecting mirrors 11a and 11b.

Therefore, according to the above configuration, the light emitted from the end of the aperture portion 3a of the aperture type fluorescent lamp 3 reaches the document 4 at a higher rate than the light emitted from the center portion. . Then,
The difference in the amount of light between the edges and the center is compensated for, and the amount of light irradiated onto the document 4 becomes approximately constant in the width direction of the document 4. Furthermore, since the second reflecting mirrors 11a and 11b are only provided on the upper bottom surface of the bridging member (supporting member) 7b that supports the first reflecting mirror 9, another light source may not be provided at the end. Compared to conventional exposure equipment that reduces the light intensity at the center of the fluorescent lamp or is equipped with a light distribution regulating plate, the number of parts and assembly man-hours are reduced, resulting in lower costs and more compact size.

Note that the present invention is not limited to the above embodiments.
Although an aperture type fluorescent lamp is used as the light source in this embodiment, a type of fluorescent lamp that emits light in the entire circumferential direction may also be used. Furthermore, although a mirror is used as the reflective member, a reflective tape or reflective paint may also be used.

(Effects of the invention) As explained above, according to the invention, at the edge of the document in the width direction, not only the direct light from the light source and the reflected light from the first reflecting member, but also the direct light from the second reflecting member As a result, the amount of light irradiated on the document in the width direction is almost constant. Since only the second reflecting member needs to be provided, the increase in parts is minimal, and the second reflecting member is easy to assemble, so the number of parts and assembly man-hours are small. A compact exposure device can be realized at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an embodiment of the present invention;
2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is a sectional view taken along the line BB in FIG. 1. 1...Exposure device, 2...Original table glass, 3...
Aperture type fluorescent lamp, 3a...Aperture portion, 4...Original, 5...Gradient index lens, 6...Photosensitive drum, 7a, 7b...Bridging member, 8a, 8b...Light shielding Members, 9...first reflecting mirror, 10...shutter, 11a, 11b...second
reflector.

Claims (1)

[Claims for Utility Model Registration] A tubular light source that is arranged in the width direction of the document, and a part of the emitted light is directed directly toward the document, and a support member that is arranged in parallel with the light source at a certain distance. a first reflecting member supported by the light source that receives light that is not directly directed toward the original and reflects it toward the original; the light reflected from the original is directed between the first reflecting member and the light source. In an exposure apparatus that focuses light onto a photoreceptor through a lens, a first position on the supporting member near the center of the first reflecting member and close to the lens; A second reflective surface of which the reflective surface faces the document only at the second position of the second position on the support member near the end of the first reflective member and close to the lens; An exposure apparatus characterized by being provided with a member.