JPS6186742A - Supplemental symbol recording device - Google Patents

Abstract

PURPOSE:To automatically perform correct copying, by providing an automatic image density controller which receives reflecting lights from the display surface of a supplemental symbol display device and original and makes the density of the recorded picture image uniform by means of the display surface and original in accordance with the light receiving condition. CONSTITUTION:When an original 11 is illuminated with a lighting lamp 10, reflecting light from the surface of the original 22 expose 13 a photosensitive body through an optical system 12. On the other hand, the reflecting light of the light lighting the proceeding information section of the original or a supplemental symbol display device 11 is measured by means of a photoreceptor element 14. By controlling the lighting lamp 10, charger 16, and developing bias 17 by feeding back a control value obtained by means of an electric control circuit 15 to each of them, the optimum copy 20 which is adjusted to the light quantity, charging, and developing bias in accordance with the density of the original or supplemental symbol display device is obtained through a transferring section 18 and fixing section 19.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an auxiliary symbol recording device in an electronic copying device or the like capable of recording symbols such as letters and numbers at the same time as copying a document.

<Prior art> Conventionally, in order to organize copy paper when it is counterfeit in an electronic copying device,
A part of the document table is equipped with an auxiliary symbol display device using a liquid crystal as a display element, and the display symbols are projected onto the exposed surface of the document during copying, and characters are printed on a portion of the copy paper.

An auxiliary symbol recording device for recording auxiliary symbols such as numbers has been proposed.

However, such conventional auxiliary symbol recording devices have the following problems. Namely.

Types of manuscripts include white background manuscripts, newspapers, and blueprints.

There are black originals with a colored background, originals with a white background and low density, etc. For example, when copying an original with a black background, set a higher exposure amount than an original with a white background, and when copying an original with a white background, For originals with low density, optimal copying can be obtained by setting a small exposure amount.

Conventionally, the exposure amount is adjusted manually or automatically depending on the type of document, but if the density of the display surface of the auxiliary symbol display device and the background of the document are significantly different, Even if the content is copied properly, the recording state of the auxiliary symbols is poor. This problem could easily be solved by installing a dedicated optical system in the auxiliary symbol recording device to determine the exposure amount only for the display surface, but this would make the device significantly more complicated and would result in a significant increase in cost. There is a big problem.

<Object of the Invention> The present invention has been made in view of the above-mentioned problems, and its purpose is to provide an auxiliary symbol recording device that can obtain an optimal composite image of an auxiliary symbol and a document through simple control. It is about providing.

<Embodiment> FIG. 1 is a block diagram of the main parts of an electronic copying machine that employs an auxiliary symbol recording device according to the present invention.

In the figure, reference numeral 1 denotes a document table consisting of a transparent glass plate 75), and numeral 2 denotes an auxiliary symbol display device embedded in the left end of the document table 1, which consists of a liquid crystal display element.

3 is an illumination lamp, 4 is a first mirror, 5 is a second mirror, 6
is a third mirror, 7 is a condensing lens, and 8 is a fourth mirror, forming an optical system. This optical system moves in the direction of the arrow in the figure, so the image is projected onto the screen 11.
The image is then projected onto the photosensitive drum 12.

Since the photosensitive drum 12 is charged by the charging charger 14, an electrostatic latent image is formed on the photosensitive drum 12 by the above projection. Once the latent image is formed, development by the developing unit 14, transfer by the transfer charger 15, and static elimination by the static elimination charger 16 and static elimination lamp 17Vc are performed in sequence, and copying onto copy paper is performed.

Further, numeral 9 in the figure is a photoelectric conversion element for detecting the density of the document, and as shown in detail in FIG. It is provided at a position where it can receive the reflected light from the auxiliary symbol display device 2 embedded in the end portion of the auxiliary symbol display device 2 and/or the reflected light from a reflector described later.

The conversion signal of this photoelectric conversion element is sent to an automatic image density control device which will be described later.

FIG. 3 is a diagram schematically showing the control system (dotted line) and copying process (solid line) of the automatic image density control device.

Now, when the original 11 is irradiated with the illumination lamp 1o, the reflected light is used to expose the photoreceptor 13 by the optical system 12. On the other hand, the reflected light of the light that has irradiated the document or the preceding information section of the auxiliary symbol display device 11 is photometered by the light receiving element 14VC, and the control value obtained by the electric control circuit 15 is measured by the illumination lamp 10. By controlling each part of the charger 16 and the developing bias 17, the amount of light, charging and developing bias are adjusted according to the density of the original or the auxiliary symbol display device, and the transfer 18,
After fixing 19, an optimum copy 2o can be obtained.

The above image density automatic control device uses a lighting lamp.

Although three parts, the charger and the developing bias, are controlled to obtain the optimum copy, it is also possible to control only one of these parts.

FIG. 4 shows an example in which only the illumination lamps are controlled. In the figure, the same parts as in FIG. 1 are given the same reference numerals.

The auxiliary symbol display device 2 consisting of a liquid crystal display element is provided on the front side of the document table 1 in the figure. Therefore, when exposure starts now, the display surface of the auxiliary symbol display device 2 is first illuminated by the illumination lamp 3. The reflected light is received by the charge conversion element 9. When the reflected light is received, the electric control circuit obtains a control value according to the amount of received light, and the amount of light from the illumination lamp 3 is controlled based on this control value, so that the auxiliary symbol display device 2 is properly exposed. Subsequently, the illumination lamp 3 illuminates the original 21, and when the reflected light is received by the photoelectric conversion element 9[, the light amount of the illumination lamp 3 is controlled by the same control operation as described above, and the original 21 is properly exposed. Ru.

Therefore, even if the densities of the surfaces of the auxiliary symbol display device 2 and the original 21 are different, the display contents of the display device can be recorded on the copy paper as a uniform image similar to the original.

In addition, FIG. 5 shows the reading position of the preceding information (photometric area 22
) is limited to the center of the document 21, and an auxiliary symbol is desired to be added to the edge of the document. In this case, the positions of the photometric area 22 and the auxiliary symbol display device 2 are different and the reflected light from the display device cannot be received, but the amount of reflected light is the same as when the display device is not displayed in the photometric area 22. The reflector 23 has a density that allows a certain amount of reflected light to be obtained.
By providing this, proper exposure of the display device can be obtained.

Further, FIGS. 6 to 8 show the case where the reading position (photometric area 22) of the preceding information covers the entire surface of the original 21. In FIGS. In FIG. 6, a reflector 23 is extended in the form of a band next to the auxiliary symbol display device 2. In this case, the reading section uses the reflector 23 to read the leading edge of the document (display section) with almost uniform density. In addition, the display contents of the display unit 2 can be properly copied, and the portion corresponding to the reflector 23 is copied in white.

In FIG. 7, the auxiliary symbol display device 2 itself is extended into a band-like shape as shown, and in this case, an optimal composite copy can be obtained without providing a special reflector. Furthermore, the eighth
The figure is devised to effectively implement the present invention, and the reflector 23 is exposed at the start of exposure of the auxiliary symbol display device 2.

A band-shaped reflector 23 is embedded in the left end of the document table 1, and an auxiliary symbol display device 2 is provided on the right side of the reflector 23, giving it an IC feature.

Usually, the area in front of the document exposure start part of the document table 1 is painted white, and in order to prevent fatigue of the photoreceptor (a), control is added to reduce the amount of light when the illumination lamp 3 starts up. This is because the illumination lamp does not rise sufficiently at the start of exposure at the tip of the symbol display device). In particular, with current liquid crystal display elements, the density is the same as or higher than that of originals with dark backgrounds, so the amount of exposure of the liquid crystal display elements needs to be about the same as when exposing an at/'1 original with a dark background. . Therefore, if there is white paint before the exposure start part, the illumination lamp 3 will not start up sufficiently before exposure starts, and after reading the density of the liquid crystal display element as advance information, the illumination lamp will be adjusted to the appropriate exposure amount for the liquid crystal display element. Even if controlled so as to be controlled, since the light intensity starts from a low level, the copying state of the liquid crystal display element, that is, the tip of the auxiliary symbol display device 2 will be poor due to insufficient exposure due to a delay in response when the exposure of the liquid crystal display element starts. There are cases.

Therefore, the exposure amount is controlled by first receiving the reflected light from the reflector 23 having the same density as that of the display device, and the auxiliary symbol display device 2 is exposed when the proper exposure has been achieved. Note that the density of the first reflector 23 may be higher than the density of the display device 2, but the reflector 23 is exposed to the same amount of light as white on the photoreceptor surface with the exposure amount of the illumination lamp controlled by photometry. It is necessary to keep the concentration within the range. However, in order to obtain an optimal copy of the auxiliary symbol, it is better to set the density of the first reflector 23 to be approximately the same as the density of the display device 2. Note that the reflector 23 may have a size that matches the photometric area.

FIG. 9 shows an example in which the apparatus of the present invention is applied to an original moving type copying machine whose optical system is composed of a convergent light transmitting array (optical fiber lens) 24.

FIG. 10 is an enlarged view of the main part. Photoelectric conversion element 9/I
i Similar to the embodiments already described, a part of the reflected light from the auxiliary symbol display device 2 or the reflector 23 and the original 21 is received, and the exposure amount of the illumination lamp 3 is controlled by the control circuit according to the amount of received light. to obtain an optimal synthetic copy.

The above two embodiments are examples in which the liquid crystal display element constituting the auxiliary symbol display device is embedded in the original table, but for example, the liquid crystal display element may be placed above or below the document table, or If the copying apparatus is of a type that exposes a document by wrapping it around a document drum, the same effect can be obtained even if the liquid crystal display element is placed on the document drum.

Furthermore, a solid state display element such as an ECD (electrochromic display) may be used instead of a #:tTN type liquid crystal display element as the auxiliary symbol display device.

<Effects of the Invention> As explained in detail above, the auxiliary symbol recording device of the present invention receives reflected light from the display surface of the auxiliary symbol display device and the original, and records the display surface and the original depending on the light reception state. Equipped with an automatic image density control device that makes the image density uniform, easy control ensures proper copying of auxiliary symbols depending on the type of document (
It can be carried out automatically regardless of the degree of

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a copying machine employing the device of the present invention;
Figure 2 is a detailed view of the main parts, Figure 3 is a diagram showing the general control system and copying process of the automatic image density control device, and Figure 4 is a schematic configuration diagram of the copying device that controls the exposure amount of the illumination lamp. , FIG. 5 to FIG. 8 are views showing examples of installation of the reflector and the auxiliary symbol display device, and FIGS. 9 and 10 are views showing other embodiments. 1 is an original table, 2 is an auxiliary symbol display device, 3 is an illumination lamp, 9#- is a photoelectric conversion element, 15 is a control circuit, and 23 is a reflector. Agent Patent attorney Aihiko Fuku (2 others) No. 2m Fig. 3 Fig. 4 @ 11146 Fig. 7 Fig. 8 ■ Fig. 9 Fig. 1 OI! lI

Claims (1)

[Scope of Claims] 1. In an auxiliary symbol recording device in an electronic copying device or the like that can record symbols such as letters and numbers at the same time as copying a document, characters are placed in a position that can be illuminated by an illumination lamp of an imaging optical system of the document. , an auxiliary symbol display device capable of displaying symbols such as numbers, and a light receiving means for receiving reflected light from the display surface of the display device and the document, and recording by the display device and the document according to the light receiving state. An auxiliary symbol recording device characterized by being equipped with an automatic image density control device that makes the density of an image uniform. 2. The auxiliary symbol recording device according to claim 1, wherein the image density automatic control device is configured to control an illumination lamp, a charger, and a developing bias individually or in combination. 3. A patent characterized in that the above-mentioned auxiliary symbol display device is formed in a band shape with substantially the same width as the exposure width by the illumination lamp, and is arranged within the exposure area so as to be parallel to the width direction of the document. An auxiliary symbol recording device according to claim 1. 4. The above-mentioned auxiliary symbol display device includes a reflector having a density equal to or higher than that of the display surface, and is configured such that the light reflected by the reflector can be received by the light receiving means. An auxiliary symbol recording device according to claim 1. 5. The reflector is formed in a band shape with substantially the same width as the exposure width of the illumination lamp, and is arranged in the exposure area parallel to the width direction of the document. Auxiliary symbol recording device according to scope 1. 6. Claim 1, characterized in that among the auxiliary symbol display device, the document, and the reflector, at least the reflector is arranged to be exposed to light before the auxiliary symbol display device. 3. The auxiliary symbol recording device according to paragraphs 3 and 5.