JPS6024539A - Optical device - Google Patents

Abstract

PURPOSE:To execute satisfactorily an image exposure without reflecting stray light to a part to be exposed, by providing a light shielding body for shielding other light than reflected light from a body to be irradiated. CONSTITUTION:At the time of an image exposure, light of an exposing lamp 5 is irradiated on an original P directly and by being reflected by a reflecting surface of a reflector 6, scanned, and its reflected light is led onto a photosensitive drum 21 through a mirror 7, the first and the second mirrors 8a, 8b, a lens 9, a mirror 10 and a slit 11, and an original image is formed. At the time of this image exposure, sometimes other light than reflected light from the original P, for instance, stray light M is made incident toward the second mirror 8b, but it is shielded because a light shielding plate 17 is provided between the first and the second mirrors 8a, 8b. Accordingly, it is reflected by the second mirror 8b, and not led to a photosensitive drum 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical device included in, for example, an electronic copying machine.

[Technical background of the invention and its problems]

This type of optical device irradiates the original with the light from the exposure rung directly and by reflecting the light from the reflective surface of the flapper as a reflector. By the way, as shown in FIG.
The optical lens C has first and M2 reflectors a and b arranged in a substantially V-shape and spaced apart and facing each other to reflect and guide the light from the first exposure rung as shown by the arrow. Stray light that is not emitted from the photoreceptor drum is reflected by the second reflector as indicated by arrow M, for example, and the conductive force is reduced, resulting in an inconvenient force in which good image exposure cannot be expected.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to provide an optical device that prevents light other than light reflected from the irradiated object 75) from entering the reflector. This is what it means.

[Summary of the invention]

In order to achieve the above object, the present invention is provided with a light body that blocks light other than light reflected from an irradiated object toward a reflector. This will be explained with reference to one embodiment. In the figure, a main body 8 of a 1/d electronic copying machine is provided with a document table (transparent glass plate) 2 on the top surface of the main body I on which a document P is placed. The document P placed on the document table 2 is pressed down by a document presser 3. Further, an exposure system 4 is provided in the upper part of the main body 1 and faces the lower surface side of the document table 2. This exposure system has four exposure lamps 5,
A reflector 6, a mirror 7, and first and second mirrors 8a, gb as reflectors.

It is composed of a lens 9, a mirror 1o, and a slot II. said exposure rung 5 and mirror 7.8a,
Mirror 8b is reciprocated in the direction of the arrow by a drive mechanism (not shown).At this time, mirror 8m58b moves at half the speed of mirror 7 in order to keep the optical path length constant. force, the first and second mirrors 1ja, 8b
The mirrors 8a and 8b are arranged in a substantially V-shape as shown in FIG.
One side of the carriage 12 is provided with a fitting part 13 as shown in Figures A14 and 5, and the other side is provided with a locking piece I4. , the fitting portion I3 is slidably fitted onto the shaft 15, and the locking piece 14 is movably locked onto the rail 16. Further, the center of gravity iG of the carriage 120 and the point of application F of the power for driving the carriage horn I2 are on the same straight line perpendicular to the scanning direction and pass through the center O of the shaft 16. .

Roughly speaking, the locking piece I4 of the carriage 12 is connected to the first mirror 8.
It is designed to act on the optical axis K of the second mirror 8b from a, and is structurally strengthened. and,
A light-shielding plate 12 as a light-shielding body is provided on this carrier 12, and the first and second mirrors 8m of this light-shielding plate 12.

8b, one slit 18 is provided. The slit 18 is connected to the first and second mirrors 11g, gb.
It is formed with dimensions that do not block the optical path between them, and light other than the light reflected from the original P is blocked by the light shielding plate I2.

During the image path light, the exposure rung 5 is turned on and travels, and the light from the exposure rung 6 is reflected directly and by the reflective surface of the reflector 6 to illuminate the document P and scan it. Then, the reflected light from the original P is reflected by the mirror 1, the first and second mirrors Ja and LbjC, and then reflected by the mirror 10 via the lens 9.
Photosensitive drum 2 as an exposed part through slit 11
The image of the document is guided by I-hi (slit exposure).

By the way, during this image exposure, light other than the reflected light from the document P, such as light M (stray light), may try to enter the second mirror 8bK as shown in FIG. Since the light shielding plate 17 is provided between the second mirrors 8h and 8b as described above, the light M is irradiated and shielded from the light shielding plate 17V. The image exposure is performed satisfactorily without being guided to the drum 21.

〔Effect of the invention〕

As explained above, the present invention irradiates an irradiated object with light from a light source, and the reflected light is reflected by a reflector and guided to an exposed part. Since the light shielding body is provided to shield light other than light reflected from the light source, stray light is not reflected to the exposed area as in the conventional case, and image exposure can be carried out favorably.

[Brief explanation of drawings]

FIG. 1 is a side view showing a conventional example, FIGS. 2 to 4 show an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram showing an optical device provided in an electronic copying machine. FIG. 3 is a side view showing the main parts, FIG. 4 is a plan view thereof, and FIG. 5 is a front view thereof. 5...Light source (exposure run power, P...Irradiated object (IiA
(original), 21...Exposed area (photosensitive drum), 17...
Light blocking body (light blocking plate). Applicant's representative Patent attorney Takehiko Suzue Figure 2 Figure 4 Figure 5 b

Claims (1)

[Scope of Claims] (ii) In a device in which light is irradiated onto an irradiated object by a light source, and the light from the irradiated object is reflected by a reflector and guided to an exposed part, the light is directed toward the reflector. An optical device comprising a light shielding body that blocks light other than light reflected from an irradiated object. (2) The optical device according to claim 1, wherein the light body holds a reflector and is movably provided.