JPS6024534A - Optical device - Google Patents

Abstract

PURPOSE:To reduce power consumption and to eliminate stray light by providing an auxiliary reflecting part for reflecting the light going toward other part than the prescribed width part of an object to be irradiated, to a light source. CONSTITUTION:The light of an exposing lamp 5 is irradiated to an original P directly and by being reflected by the reflecting surface 6a of a reflector 6, scanned, and the reflected light is reflected by mirrors 7, 8 and 9, and thereafter, led onto a photosensitive drum 21 through a lens 10, mirror 11 and a slit 12, and an original image is formed. When exposing this image, the light going toward other part than the slit width A of the original P from the exposing lamp 5 is reflected by an auxiliary reflecting part 6' and returned to the posing lamp 5 within a range of theta. Accordingly, the light quantity of the exposing lamp 5 is increased by this returned portion, and the light is irradiated concentrically to the slit width A of the original P, by which the light is utilized, and also the stray light is shielded.

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]

As this type of optical device, for example, the one shown in FIG. 1 is known. That is, in the figure, a is an exposure lamp, and the light from this exposure lamp a is reflected directly and by the glue flutter bK as a reflector, and the original P with the width A is
The reflected light from the document P is guided to the surface of the photosensitive drum via an optical element (not shown) to form an image.

However, in the past, a part of the light from the exposure lamp a (range of θ) did not reach the width AK of the document surface.
Light is not used effectively and the temperature of the document surface increases.
Furthermore, there is a problem in that it causes stray light in the optical system.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to effectively utilize the light from the light source, prevent the hot water temperature from increasing on the irradiated surface, and prevent stray light. The purpose of this invention is to provide an optical device with a high degree of accuracy.

[Summary of the invention]

In order to achieve the above object, the present invention includes a reflector that reflects part of the light from the light source to the irradiated object in a predetermined width, and the present invention includes a reflector that reflects a part of the light from the light source to the irradiated object in a predetermined width area from the light source to the irradiated object. An auxiliary reflecting section is provided to reflect light directed toward other parts to the light source.

I will clarify. In the figure, reference numeral 1 denotes a main body for electronic photographing, and a document table (transparent glass plate) 2 on which a document is placed is provided on the upper surface of the main body 1. The document P placed on the document table 2 is held 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 4 exposure lamps 5
, Glue flafter 6 mirror 7 , 8 , 9 as a reflector
, a lens lθ, a mirror J1, and a slot 12. The bell light lamp 5 and mirrors 1 and 8
．． 9 is reciprocated in the direction of the arrow by a drive mechanism (not shown), and at this time, mirrors 8 and 9 move at half the speed of mirror 2 in order to keep the optical path length constant. .

On the other hand, the reflector 6 is constructed as shown in FIG. That is, the inner surface of this reflector 6 becomes a reflective surface 6a that reflects the light from the exposure land 5, and this reflected light is irradiated onto the original P with a slit width A as shown by the arrow. ing. Additionally, on the upper edge of one side of the earth and stone e-reflector 6, there is integrally molded an auxiliary reflection part 6' in the shape of a circular arc with a diameter R around the R-light lamp 5. This auxiliary reflection part e;I#'ip light lamp 5 may be the original P
The light directed toward a portion other than the slit width A is reflected by the exposure lamp 5 within a range of θ as shown by the arrow.

At the time of image exposure, the dimming lens 5 is turned on and travels, and the light from the y-light lamp 5 is reflected directly and by the scratched surface 6a of the reflector 60 to illuminate the original P and scan it. Then, the reflected light from the original P passes through the mirror 7.8.
．． 9, the light is reflected by a mirror 11 via a lens 10, and is guided onto a photosensitive drum 21 via a slit 12, where the screen image is formed (slit exposure).

During this image exposure, a beam of light from the exposure lens 5 toward a portion of the document P other than the slit width A is reflected by the auxiliary reflection section 6' of the flaper 6 and returned to the exposure lamp 5 within a range of .theta. Therefore, the field of view of the r-light lamp 5 is increased by the amount returned, and the slit width A of the original P is irradiated with light in a concentrated manner.

In this way, the light from the exposure lamp 5 is applied to the width A of the document P.
Since the K buds are irradiated centrally, the light can be used effectively, stray light can be blocked, and the temperature of the document table 2 can also be prevented from rising.

〔Effect of the invention〕

As described above, the present invention is provided with a reflector that reflects part of the light from the light source onto the irradiated object in a predetermined width, and in which the reflector is provided with a part other than a predetermined width part of the irradiated object from the light source. Since the auxiliary reflection part is provided to reflect the light directed toward the part of the object to the light source, the light from the light source can be effectively applied to a predetermined width of the irradiated object, thereby reducing power consumption and eliminating stray light. When used in , copying machines, etc., accurate image exposure becomes possible.

Furthermore, it is possible to prevent the temperature of the document table from rising, resulting in a safe effect.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a conventional example, Fig. 2 is a schematic configuration diagram showing an optical device provided in an electronic copying machine which is an embodiment of the present invention, and Fig. 3 is a side view showing its reflector. It is. 5... Light source (exposure lamp'), P... Irradiated object (original), 6... Reflector (S7 reflector), 6'... Auxiliary reflection section.

Claims (1)

[Claims] A reflector that reflects part of the light a from the light source onto the irradiated object in a predetermined width, wherein the reflector directs light from the light source toward a portion of the irradiated object other than the predetermined width portion of the irradiated object. An optical device characterized by being provided with an auxiliary reflecting section for reflection.