JPS5949556A - Exposing device of copying machine - Google Patents

Abstract

PURPOSE:To eliminate a specific color on a copy original automatically from a copy paper, by allowing a light source for exposure to emit the light of a specific wavelength corresponding to the color to be erased from the original. CONSTITUTION:An original 4 is illuminated with two light sources 2 and 3 for exposure different in wavelength region from each other and is exposed onto a photosensitive drum 6 through a lens 5. Adjusting devices 9 and 10 which adjust the quantity of light are connected to light sources 2 and 3, respectively. A dimmer 7 is provided for controlling light sources 2 and 3 so that the intensity of the light of them is held in a prescribed intensity. In this constitution, the intensity of the light of light sources 2 and 3 is adjusted, and wavelengths of light sources for exposure are changed, thus erasing a desired color. A single light source may be used instead of plural light sources 2 and 3 different in wavelength region, and the wavelength region of the light of this light source is changed by a color filter.

Description

[Detailed description of the invention] The present invention relates to an exposure device for a copying machine.

In conventional copying machines, the main focus is on reproducing the image on the original, and no particular consideration is given to intentionally deleting an image of a specific color on the original from the copy paper. Therefore, it is generally impossible to selectively copy only specific information on a document. For example, if you want to copy only the original characters of the original after checking the original and adding writing or anglining, such writing must be erased before copying.

SUMMARY OF THE INVENTION An object of the present invention is to provide a copying machine that can automatically delete specific colors on a copy document from copy paper and is useful in the above-mentioned situations.

The present invention achieves the above object by controlling the wavelength of an exposure light source in the exposure process of a copying machine. The present invention relates to an exposure position of a copying machine characterized by including an exposure light source device capable of emitting light.

According to the present invention/embodiments, the exposure light source device includes a plurality of exposure light sources capable of emitting light having wavelengths capable of erasing each of the colors corresponding to the colors on the document to be erased. , and an adjustment device capable of adjusting the amount of light of each of the light sources. In this way, depending on the type of color to be erased, the light intensity of the light source of a specific wavelength is increased and the light intensity of the light source of other wavelengths is weakened, thereby obtaining a copy in which the desired color on the document is erased. I can do it.

As another embodiment of the present invention, an optical filter can be used to expose an original only to light of a specific wavelength from a light source. According to such an exposure apparatus, a desired purpose can be achieved with only a single light source by using a light source with a wide wavelength range and taking measures such that filters of each color can selectively block the light source. You can also do that.

The number of exposure light sources or the number of color filters used in the copying machine of the present invention can be appropriately selected depending on the number or type of desired colors to be erased. In practice, the objective is achieved with a relatively simple tS by arranging the exposure light source (or color filter) so that the λ colors (eg red and blue) can be selectively erased. Of course, the apparatus of the present invention does not erase specific colors on the original, but operates to copy the original as it is by adjusting the light intensity of the exposure light source, eliminating the optical filter, etc. You can also do that.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings in order to further clarify the features of the present invention.

1 to 3 are graphs for explaining the present invention in detail. Assume that black, blue, and red images exist on a document to be copied. When you want to copy all three-color images on a document through a photosensitive material with a sensitivity as shown by (using a similar filter), the intensities of short-wavelength light and long-wavelength light are made similar, such as Ll and L2, respectively. If you struggle,
The blue image potential (v8) and red image potential (vR) of the surface potential (■5) of the sensitive material are also approximately the same as shown in the figure, and both the blue image and the red image are copied. If you want to erase the blue image, as shown in Figure Ω, by adjusting only the intensity of the light in the blue region wavelength () to be strong, the surface potential of the sensitive material (■8) of the blue image can be increased. descends, erasing the blue image from the copy. Conversely, if you want to erase the red image, adjust so that only the intensity of light with a wavelength in the red region (L2) becomes strong, and the surface potential (vR) of the sensitive material in the red region will drop, causing the red color to disappear from the copy. The statue disappears (3rd
figure). In all cases, the light of the black image is completely absorbed, does not reach the sensitive material, and the surface potential does not drop, so that it appears as an image on the copy paper.

7 and 3 show typical examples of an exposure device for a copying machine. FIG. 7 shows a conventional device, and FIG. This is an example of the device of the present invention.

In FIG. 7, an image of a document 4 is projected onto a photosensitive drum 6 through a lens 5 by illumination from an exposure light source 1, thereby forming a latent image on the drum. Here, in the conventional apparatus shown in the figure, only an image of a predetermined color (actually black) is copied depending on the wavelength of a single light source and the sensitivity of the photoreceptor; It is not intended to selectively erase colors.

On the other hand, in the exposure apparatus of the present invention as shown in FIG.
．． 3 illuminates the original 4, and the lens 5
A latent image corresponding to the document is formed on the photoreceptor drum 6 via the photoreceptor drum 6 . Adjustment devices ν'9 and 10 for adjusting the amount of light are connected to the light source 2.3, respectively. Note that 7 is a light control device that controls the intensity of the light from the light source to maintain it at a predetermined intensity. If you configure it like this,
As explained in connection with FIGS. 1-3, a desired color can be erased by adjusting the intensity of the light from light sources 9 and 10 and changing the wavelength of the light emitting source.

It goes without saying that the exposure apparatus of the present invention is not limited to the embodiment shown in the dimensional drawing. For example, a larger number of light sources than shown in the figure may be used to erase a greater variety of colors or to erase colors more precisely. Also, as mentioned above, instead of using multiple light sources with different wavelength ranges,
The wavelength region of a single light source may be changed by using a color filter.

If the exposure device of the present invention is used, for example, items that do not need to be copied on a black original can be colored red (or blue).
Even if you make additions, such unnecessary information will be automatically deleted by a simple copying operation.

Thus, the exposure apparatus of the present invention provides great convenience in office processing and the like.

[Brief explanation of the drawing]

1 to 3 are graphs for explaining the present invention in detail. FIG. 7 is a perspective view showing a conventional exposure apparatus. FIG. S is a perspective view showing an embodiment of the exposure apparatus of the present invention. 1.2.3: Exposure light source, 4: Original, 9, lO: Light amount adjustment device. 1r1M $4 Figure 5

Claims (1)

[Claims] The method includes an exposure light source device that has a specific wavelength of light capable of erasing a specific color of the original to be copied, and that can emit light of the specific wavelength depending on the color of the original to be erased. Features: Copying machine exposure device.