JPH0243598A - Picture display device - Google Patents

Abstract

PURPOSE:To detect the initial position of a picture without erasing the picture by forming position detecting markers on symmetrical positions of a recording medium and detecting the picture on the initial position of a display picture by the markers formed on two positions of the picture through a position detecting sensors. CONSTITUTION:A pair of markers 30 are fixed on the symmetrical positions on the surface of the belt-like recording medium 4 and a marker detecting sensor 31 for detecting the markers 30 is fixed on the device body. The initial positions for two front and rear pictures are detected by the pair of markers 30 and the sensor 31. Thus, the initial positions of the display pictures can be detected by the markers 30 formed on two positions of the pictures. Consequently, the initial position of the picture can be detected without erasing the picture.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Use) The present invention relates to an image display device that displays an image on a rotating image carrier.

(Prior Art) A conventional example of this type of image display device is shown in FIG. In this figure, 1 is a main body of the apparatus supported by a stand 2 at an angle of 2 degrees, and 3 is a display section thereof. The image displayed on the display section 3 is formed by toner on a belt-shaped recording medium (magnetic material) 4 that is an image carrier.
is rotated in the direction of arrow A in the figure by support rollers 5, 6, 7.8. The lower large diameter roller 6 is connected to a driving motor 9 by a timing belt. Reference numeral 10 denotes a control board equipped with a control circuit such as a microcomputer (not shown) for controlling the entire display device. Reference numeral 11 denotes a recording unit that applies one line of toner to the recording medium 4 in the horizontal direction. Reference numeral 12 denotes an image erasing section that removes unnecessary toner from the recording medium 4.

As an image forming method in the recording section 11, there is a method known, for example, from Japanese Patent Publication No. 51-46707. In this method, as shown in FIG. 3, conductive magnetic toner 13 is conveyed onto a non-magnetic cylinder 15 by a rotating magnet 14, and passed over a recording electrode 16 made of a magnetic material. Then, a voltage corresponding to an image is applied between the conductive layer 17 of the recording medium 4 having an insulating layer 18 on its surface and the recording electrode 16, thereby causing the toner 13 to adhere to the recording medium 4 and forming an image.

A detailed configuration example of the above-mentioned recording electrode 16 portion is shown in FIG. As shown in this figure, the recording electrode 16 and the drive circuit section 19
are connected by a flexible printed circuit board 20. The side of the flexible printed circuit board 20 near the recording electrode 16 is in contact with or adhered to the non-magnetic cylindrical member 15, and is bent in the horizontal direction and separated from the non-magnetic cylindrical member 15. Set them up side by side. The wiring of the flexible printed circuit board 20'' is provided bypassing the opening 21 as shown in this figure. Toner 13 for image formation circulates on the non-magnetic cylindrical member 15 through the opening 21 due to the rotation of the magnet 14 contained in the non-magnetic cylindrical member 15 .

When a signal voltage of, for example, several tens of volts is selectively applied from the drive circuit 19 to the recording electrode 16, the toner 13 adheres to the recording medium 4, and when the signal voltage is 0 volts, the l-toner 13 adheres to the recording medium. do not.

In general, the above-mentioned image display device is connected to an image reader, for example, as an image human-powered device, as shown in FIG.

In this figure, 101 is an image reader, and 102 is a display device. Here, 103 is the image reader 101
This is a ready signal (READY) indicating that the image signal 107 can be received from. Reference numeral 104 is a start number 13 (S
TART). The display device 102 is the image reader 1
When the start toy number 104 is received from 01, if the ready signal 103 is "true", the drive of the recording medium 4 is started via the drive motor 9, and the moving speed of the belt-shaped recording medium 4 is kept constant. . At that time, the ready signal 103 is false.
When this is the case, the star 1 signal 104 is ignored, the recording medium 4 is not driven, and all other controls necessary for the display operation are not started.

Further, 105 is an image reader 10 from the display device 102 in order to synchronize the image displayed on the display unit 3 in the vertical direction.
It is a pulse signal (H5YNC) output to 1, and is generally a position detector connected to a motor 9 that drives the recording medium 4, such as a rotary encoder (not shown).
is made based on the output pulse of image reader 10
1 receives a pulse (knee q 105) and sends out an image signal 107 for one line.

108 is an image synchronization clock signal (to VCL) for synchronizing the image displayed on the display unit 3 in the horizontal direction;
1 to the display device 102.

Reference numeral 108 denotes an interface f line that performs communication for outputting instruction commands I~ from the image reader 101 to the display device 102 and for importing the state of the display device 102 to the image reader 101. A timing chart of the above signals 103 to 107 is shown in FIG.

(Problem to be Solved by the Invention) However, while the conventional image display device described above has the advantage that it does not require a power source to maintain the image after it has been displayed on the screen, ,
If the screen becomes misaligned due to vibrations, etc. after the power is turned OFF, when the power is turned ON again, the screen must be rotated at least half a turn to detect the initial position, which may result in the display being distorted. It had the drawback of erasing the screen.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and to provide an image display device that can detect the initial position of a display screen without erasing the image being displayed.

[Means to solve the problem]

In order to achieve this object, the present invention provides a plurality of position detection markers separated by a predetermined interval on an endless belt-shaped recording medium, and detects the initial position of the display screen by a position detection sensor that detects the markers. Features.

(Function) In the present invention, markers for position detection are provided at symmetrical positions on the recording medium, and the initial position of the display screen is detected by the position detection sensor at two markers on the screen.
The initial position of the screen can be detected without erasing the screen, and thereby the initial position can be set and adjusted (corrected) without affecting the displayed image even if the power is turned 0N10FF.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Figures 1(A) to ([1)] show the main structure of an embodiment of the present invention, and modeled the roller 5.6°7.8 and the recording medium 4 of the image display device in Figure 2. It is something.

As a means for detecting the position of the display screen, as shown in FIG. It is fixed to the body of the device main body 1.

This pair of markers 30 and sensor 31 can detect the initial position for two screens, front and rear.

Furthermore, as shown in this figure (B), another marker detection sensor 32 may be attached near the sensor 31 described above. In this case, when the power is switched from 0N10FF, the displayed screen The recording medium 4 is rotated in the direction of the arrow 33 in the figure within a movement width that does not have any influence, and one marker detection sensor 32 detects the marker 30. When the marker 30 is detected, the recording medium 4 is reversely rotated in the arrow direction 34 shown in FIG. 3(C), and the other marker detection sensor 31 detects the initial position.

When the marker 30 cannot be detected by the marker detection sensor 32 and exceeds a predetermined movement width, the recording medium 4 is reversely rotated in the direction of the arrow 34 in FIG. Clears the display screen.

In this way, two marker detection sensors and two markers are used.
By providing two, it is possible to easily set and correct the initial position without affecting the displayed image during the original 0N10FF.

Other configurations and operations are similar to those of the conventional example shown in FIGS. 2 to 6, so detailed explanation thereof will be omitted.

[Effects of the Invention] As described above, according to the present invention, position detection markers are provided at symmetrical positions on the recording medium, and the position detection sensor detects the initial position of the display screen using the two markers on the screen. As a result, the initial position of the screen can be detected without erasing the screen.
Even with 10FF, the initial position can be set and adjusted (corrected) without affecting the displayed image.

[Brief explanation of the drawing]

1 (8) to (D) are schematic diagrams showing the general configuration and usage mode of an embodiment of the present invention; FIG. 2 is a partially cutaway perspective view showing the external appearance and main configuration of the image display device; The figure is an explanatory diagram showing the principle of the recording part in Figure 2, Figure 4 is a perspective view showing the detailed structure of the recording part in Figure 3, and Figure 5 is a diagram showing the structure of the image display device and image reader in Figure 2. A wiring diagram showing the connection relationship, and FIG. 6 is a timing chart showing the timing of display operation in the circuit of FIG. 5. 1...Display device main body, 3...Display section, 4...Recording medium, 5-8...Support roller, 9...Drive motor, 11...Recording section, 12...Erase Part, 16... Recording electrode, 30... Marker 31, : 12... Marker detection sensor. Figure Figure

Claims (1)

[Claims] 1) An image display device characterized in that a plurality of position detection markers are provided on an endless belt-shaped recording medium at predetermined intervals, and the initial position of a display screen is detected by a position detection sensor that detects the markers.