JPH04369636A - Image copying device - Google Patents

Abstract

PURPOSE:To prevent the device of a reader printer from being large and to prevent cost from rising even when a light receiving sensor for detecting image density is used. CONSTITUTION:A light receiving sensor 21 is attached to a scanning case 10 holding mirrors 11 and 12 for printing which move in an optical path when a reader state is switched to a printing state, and image density control is executed based on the output of the light receiving sensor 21 at the time of the preliminary scanning of the scanning case 10 (befor the scanning case 10 reaches to an exposure starting position).

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an image copying apparatus capable of switching between a reader state in which an image is projected onto a screen and observed, and a printer state in which the image is projected onto an exposure section to obtain a copied image. The present invention relates to an image copying apparatus with an image density control function that detects the density of an original image using a photoelectric conversion element or the like and automatically adjusts the exposure amount and the like accordingly.

0002

2. Description of the Related Art Conventionally, a microfilm reader printer is known as this type of device. This microfilm reader printer has a lamp 1 in FIGS. 6 and 7.
The light emitted from the irradiated microfilm F is reflected by the reflecting mirror 2 and irradiated onto the microfilm F through the illumination light reflecting mirror 3 and the condensing lens 4. The projected light from the irradiated microfilm F is transmitted through the projection lens 5 to the reader. As shown in FIG. 6, is projected onto a screen 8 by a fixed reader mirror 6 and a rotary reader mirror 7 for optical path switching that can be rotated around an axis 7a, and are arranged so as to form a right angle to each other during printing. As shown in FIG. 7, the scan case 10 supporting the printed mirrors 11 and 12 is driven by a driving means (not shown) in a direction perpendicular to the reader optical path between the scanning exposure start position indicated by the solid line and the scanning exposure end position indicated by the two-dot chain line. to scan and expose the image on the microfilm F onto the photosensitive drum 13,
This is a device that uses electrophotography to copy images onto copy paper P fed from a paper feed cassette 14 and discharges the copy paper P to a paper output tray 15. Note that around the photosensitive drum 13,
Known image forming means such as a charger, a developing device, and a transfer device (not shown) are arranged.

0003

[Problems to be Solved by the Invention] By the way, the image on the microfilm F depends on the amount of lens and illumination at the time of photography.
The finished density varies depending on many factors such as the developer temperature and development time during development. Therefore, when copying an image using a reader printer, the operator must adjust the image density according to the finished density of the microfilm F, which is cumbersome and requires trial copying of images. Therefore, the copy paper P is wasted, which is not desirable from the viewpoint of environmental protection.

[0004] Therefore, an image density control device (A
E) A reader printer with functions was considered. The microfilm density can be detected by measuring the amount of light projected by the reader printer. However, in the device using the light receiving sensor described above, as shown in FIG.
We have been guiding the light and capturing the amount of light. Therefore, a mechanism for advancing and retracting the mirror 17 is required, leading to an increase in the size and cost of the device.

SUMMARY OF THE INVENTION In view of the problems of the prior art described above, it is an object of the present invention to provide a compact and low-cost image copying apparatus.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a reader state in which an image is projected onto a screen and observed, and a copy image is obtained by projecting the image onto an exposure section. An image copying apparatus that is switched to a printer state includes a reader mirror that rotates when the printer state is switched, and a light amount detection means that adjusts image density based on the detected light amount, and the rear surface of the reader mirror is The light amount detection means performs image density control by detecting the amount of light.

[0007]

[Operation] In the image copying apparatus configured as described above, the light amount detection means receives the entire area of the image projection light and controls the image density by using the back surface of the reader mirror that rotates when the printer is switched, so it saves space. It can be controlled with a simple configuration without any need.

[0008]

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
The explanation will be based on. In the figure, symbols F, 1 to 15 are the same as those shown in FIGS. 6 and 7 above. In this embodiment, a light receiving sensor 21 is disposed on the upper side of the projection lens 5 with its light receiving surface facing the mirror 7 side, and the output of the light receiving sensor 21 is used during preliminary scanning of the scan case 10 (scan case 10 reaches the exposure start position), image density control is performed.

In this embodiment having the above configuration, when reading, the scan case 10 is stationary at a position behind the mirror 7 as shown in FIG. 1, and the image light of the microfilm F passes through the projection lens 5. , are projected onto a screen 8 via mirrors 6 and 7. On the other hand, when printing, the mirror 7 is first rotated in the direction of arrow a in FIG. 1 (clockwise direction in the drawing) by a driving means (not shown). Next, the scan case 10 moves (preliminary scan) in the direction of arrow b shown in FIG. The image light of the microfilm F is transmitted to the photosensitive drum 1 via mirrors 11 and 12 while moving in reverse (to the right in the figure).
3. Scan and expose. This scanning exposure is carried out using scan case 10.
is performed until the position shown by the two-dot chain line is reached. Even after the scanning exposure is completed, the scan case 10 continues to move, and as shown in FIG.
It stops when it reaches the rest position shown in . After the scan case 10 comes to rest, the mirror 7 rotates back to the position where it forms the reader optical path. Note that a one-dimensional image sensor (such as a CCD) may be disposed in place of the photosensitive drum 13 in the exposure section, and a copy image may be obtained using the output of the image sensor and a laser beam printer.

[0010] Furthermore, when switching from the reader state to the printer state, as described above, the scan case 10
By moving in the direction of arrow b, the light receiving sensor 21 also moves in the projection optical path, and during this time it is possible to receive the entire area of the image projection light. Therefore, based on the output of the light receiving sensor 21, the image density is determined by an image density adjusting means (not shown), and a good copy image is obtained after the series of operations described above. The image density can be adjusted by controlling the light intensity of the illumination lamp 1, but it may also be controlled by automatically making the aperture of the projection lens 5 variable or by controlling the developing bias of the developing device.

FIG. 3 shows a second embodiment of the invention. In order to simplify the explanation, the same parts as in the first embodiment are given the same reference numerals, and only the different points will be explained. In this embodiment, in order to obtain the driving force required for rotating the mirror 7 from the movement of the scan case 10, a protrusion is provided at the top of the top of the scan case 10 and protrudes in the direction of movement so as to come into contact with the mirror 7. 31 is provided, and this protrusion 3
A roller 32 is rotatably held at the tip of the roller 1 by a shaft 33. The other configurations are the same as those of the first embodiment described above. In this embodiment with the above configuration, when the scan case 10 moves in the direction of the arrow b, the roller 32 comes into contact with the mirror 7.
is rotated to the position shown by the two-dot chain line. Therefore,
According to this embodiment, the rotation driving means for the mirror 7 and its operation time in the first embodiment can be omitted, and the apparatus configuration can be further simplified and the copying operation speed can be increased.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, instead of providing the light receiving sensor 21 on the scan case 10 as in the previous embodiments, the light receiving sensor 21 is provided on the mirror 7.
It is attached to the tip of the holding member 7b. The other configurations are the same as those of the first embodiment described above. Also in this embodiment with the above configuration, the image projection light can be received when the mirror 7 rotates in the direction of the arrow a, so that the image density can be controlled inexpensively and efficiently with a simple configuration.

FIG. 5 shows a fourth embodiment of the present invention. This embodiment is of a type (single mirror scan format) in which scanning exposure is performed using a single printer mirror. That is, a holding stand 42 that rotatably holds the print mirror 41 is provided above the projection lens 5, and the holding stand 42 is movable in a direction perpendicular to the optical axis and receives light at a portion perpendicular to the optical axis. A sensor 21 is provided, and a fixed mirror group 43 for changing the optical path is provided at a position facing the print mirror 41. The other configurations of the reader optical system and exposure section are the same as in the first embodiment. In this embodiment with the above configuration, during reading, the print mirror 41 and the holding table 42 that holds it are retracted to the position indicated by the two-dot chain line. On the other hand, when using a printer, the mirror 41 and the holding stand 4
2 moves to the solid line position and stops, and the mirror 41 is moved to the holding base 4.
By rotating in the direction of the arrow within 2, scanning exposure of the image is performed. This makes it possible to receive image projection light for the purpose of image density control by utilizing the movement of the holding table 42 when switching from the reader state to the printer state.

It should be noted that the present invention is not limited to the above-described embodiments, but can also be applied to a digital image reading device using, for example, a CCD line sensor instead of an image scanning mirror.

[0015]

Effects of the Invention As explained above, the present invention enables image density adjustment with a simple configuration by attaching a light receiving sensor to the optical component holding member that moves in the optical path when switching from the reader state to the printer state. This makes it possible to measure the amount of light projected on an image, allowing the device to be made smaller and cheaper. Furthermore, since the light-receiving sensor is a moving type, compared to the conventional fixed sensor type, for sensors with the same light-receiving area,
Photometry over a wider area becomes possible, and reliability and efficiency can also be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a reader printer as an image copying apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram at the time of printing.

FIG. 3 is a schematic configuration diagram of a reader printer according to a second embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a reader printer according to a third embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a reader printer according to a fourth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a conventional reader printer.

FIG. 7 is a schematic configuration diagram at the time of printing.

FIG. 8 is a schematic configuration diagram of a conventional reader printer with an image density control device.

[Explanation of symbols]

F Micro film 5 Projection lens 6 Leader mirror 7 Rotating leader mirror 8 Screen 10 Scan case 11 Print mirror 12 Print mirror 13 Photosensitive drum 21 Light receiving sensor

Claims (1)

[Claims] Claim 1: In an image copying apparatus that can switch between a reader state in which an image is projected on a screen and observed, and a printer state in which the image is projected onto an exposure section to obtain a copy image, when switching to the printer state, An image copying apparatus characterized in that it has an optical component holding member that moves within an optical path, a light receiving sensor is attached to the holding member, and image density control is performed based on the output of the light receiving sensor.