JPH0545007B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image reading device that reads images on a film.

(Prior Art and Problems to be Solved by the Invention) Conventionally, in this type of image reading device, a short index lever is placed at the bottom of a screen that projects an image such as a micro film, and this index lever is used to detect the projected image. There is a device that moves the indicator lever to the position of the image to be read and electrically detects the position of the indicator lever to designate the reading position.

However, in this case, since the index is short, the image and the index cannot be superimposed, resulting in a problem of poor reading accuracy.

In addition, there are models in which the above indicator lever is extended and its tip is placed on the screen, but in this case, if the indicator lever is placed inside the screen, a shadow will be projected, making it difficult to read the position of the indicator lever. However, there was a problem that if the indicator lever was placed outside the screen, there was a risk of wave damage.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and its object is to provide an image reading device that improves the positional accuracy of reading by displaying indicators on the screen. Our goal is to provide the following.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an optical system for projecting a film image onto a screen;
a specifying means for specifying an arbitrary position of an image projected on a screen; an index display means for displaying an index on a portion of the screen corresponding to the position specified by the specifying means; The apparatus is configured to include a position detection means that generates a signal corresponding to the position, and a control means that controls the image reading position based on the signal from the position detection means.

(Example) The present invention will be explained below based on the illustrated example.

FIG. 1 shows an image reading device according to the present invention.

In the figure, an image on a microfilm 3 as an information recording medium is illuminated by a film illumination lamp 1 through a mirror 2, and is projected onto a screen 8 by an imaging lens 4 through mirrors 6 and 7. 5 is a switching unit for switching the projected image between screen projection and image reading. Reference numeral 9 denotes a reading position specifying device disposed on the back side of the mirror 7, and the mirror 7 has a small hole 7a for projecting an index. Note that since no image is formed on the mirror 7, the image of the small hole 7a is not projected onto the screen 8.

The image reading described above is performed as shown in FIG.

The image frames of the microfilm described above are illuminated by a film illumination lamp 1 and a mirror 2.
A projected image of the image frame is formed on a scanning plane of a one-dimensional image sensor (using a CCD, for example) 20 via an imaging lens 4 and a fixed mirror (not shown).

The one-dimensional image sensor 20 has guides 21 and 22
A wire 24 is fixed on a carriage 23 that can be moved along the
By driving the motor 25, the image is scanned and read.

A light shielding plate 26 is fixed to the carriage 23, and the scanning start position is determined by shielding a photo interrupter 27 fixedly arranged on the main body of the apparatus.

FIG. 2 shows the reading position specifying device.

In the figure, this reading position specifying device 9 is equipped with an index display means for displaying an index, and the index display means includes an index projection plate 13 having a slit 13a for projecting an index consisting of a bright line, and an index display means for displaying an index. Index projection lamp 10 that illuminates the projection plate 13
and a lens 15 for index projection. Further, a rack 14 is provided at the lower end of the index projection plate 13 to project downward, and a gear 12a fixed to a drive shaft of a pulse motor 12 is meshed with the rack 14. However, the pulse motor 1
2, the index projection plate 13 can be moved up and down via the gear 12a and the rack 14. Further, a potentiometer 11 as a position detecting means is connected to the pulse motor 12.

As shown in FIG. 3, the index projection plate 13 is
A linear slit 13a is formed in a glass plate or the like painted black, and the rack 14 extends from one side of the lower end of the index projection plate 13.

FIG. 5 is a block diagram showing the electrical control circuit of this embodiment, and shows an external device 40 such as a laser printer.
It shows that it is connected to. keyboard 3
By pressing shift key 31 of 0, CPU3
The pulse motor 12 is rotated via the driver 33 and the pulse motor 12 to move the index projection plate 13, and the output voltage obtained from the potentiometer 11 by the rotation of the pulse motor 12 is sent to the CPU 32 via the A/D converter 34. be introduced. Further, the output signal of the photo interrupter 27 described above is introduced to the CPU 32. The CPU 32 controls the reading operation of the image sensor 20 and sends an image sending start signal 42 to the external device 40 according to a control procedure described later. Further, the image output signal 43 of the image sensor 20 is supplied to the external device 40.
Furthermore, the CPU 32 controls lighting of the indicator projection lamp 10 via the driver 35.

In this embodiment, the scanning start point of the one-dimensional image sensor 20, which is positioned by the photo-inruptor 27, and the reference position of the index projection plate 13 are adjusted in advance so that they optically coincide.

In the above configuration, the reading position designation device of the image reading apparatus according to this embodiment specifies the reading position as follows. That is, when the operator presses the edit key 36 on the keyboard 30, the CPU
Reference numeral 32 connects the indicator projection lamp 1 via the driver 35.
Lights up 0. The light from this lamp 10 passes through the lens 15 through the slit 13a of the index projection plate 13.
and is projected onto the screen 8 through the small hole 7a of the mirror 7 as a bright line L, as shown in FIG. 6, and an index consisting of the bright line L is displayed at an arbitrary position on the screen. Next, keyboard 3
By operating the shift key 31 of 0, the CPU 32
The pulse motor 12 is rotated via the driver 33 to move the index projection plate 13, and the index consisting of the bright line L is moved to the end of the image to be read. When the input key 37 of the keyboard 30 is pressed, the output voltage of the potentiometer 11 linked to the pulse motor 12 is changed to the A/D converter 3.
4 to the CPU 32 as the image reading position. The CPU 32 converts the output voltage into the scanning distance of the one-dimensional image sensor 20, and calculates the scanning time by dividing this scanning distance by the scanning speed.

Thus, the sequence when outputting the image information signal of image A and the image transmission start signal to the external device 40 is as follows (FIG. 7).

First, by driving the motor 25, scanning of the one-dimensional image sensor 20 is started (step S5). Then, after counting the time corresponding to the distance between a and x specified by the bright line L (step
S6, S7), the CPU 32 outputs an image transmission start signal 42 to the external device 40 (step S8). By the generation of this image transmission start signal 42, the external device 40
can begin receiving image information signals.

Also, when image B shown by the dotted line in FIG. 6 is projected onto the screen 8 and the image start signal is changed to point x', the coordinates of point x' are detected in the same way,
The CPU 32 may convert this into the output timing of the image transmission start signal 42.

In the illustrated embodiment, a single index projection plate and means for driving and position detection thereof are provided, but it is also possible to provide a plurality of these means and project a plurality of indexes onto the screen. good.

Further, in the illustrated embodiment, the mirror 7 has a small hole 7a.
Although the index is projected onto the screen 7 by providing a mirror 7, a half mirror may be used as the mirror 7.

(Effect of the invention) The present invention consists of the above configuration and operation,
Since the index is displayed at an arbitrary position on the screen to specify the reading position, the reading position can be specified by superimposing the image on the screen and the index, and reading accuracy can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an image reading device according to the present invention, FIG. 2 is a schematic diagram showing a reading position specifying device of the image reading device according to the present invention, and FIG. 3 is a plan view showing an index projection plate. Figure 4 is a perspective view showing the image reading section;
FIG. 5 is a block diagram showing the control system, FIG. 6 is a plan view showing the image projected on the screen, and FIG. 7 is a flowchart showing the image reading operation. Explanation of symbols 8...Screen, 9...Reading position specifying device, 10...Indicator projection lamp, 11...
...Potentiometer, 12...Pulse motor, 1
3... Index projection plate, 13a... Slit, 14...
Rack, 15...lens, 32...CPU.

Claims (1)

[Claims] 1. An optical system for projecting a film image onto a screen, a specifying means for specifying an arbitrary position of the image projected on the screen, and displaying an index on a portion of the screen corresponding to the position specified by the specifying means. position detection means for generating a signal corresponding to the position of the index displayed on the screen; and control means for controlling the reading position of the image based on the signal from the position detection means. An image reading device characterized by: