JPS5974581A - Display device - Google Patents

Abstract

PURPOSE:To display picture data more quickly than normal without changing the frequency of a fundamental clock for reading out the picture data by reading out only an odd line or an even line of the picture data. CONSTITUTION:A laser driving circuit 32 flickers a laser 33 in accordance with the picture data from a memory 30 or 31. A selecting switch 39 is switched to switch the mode to the standard display mode and the double speed display mode. A clock oscillator 37 for attaining the fundamental clock K1 is connected to a control circuit 34. A motor driving circuit 36 which drives a motor 35 driving a belt-shaped photoreceptor is provided. The motor 35 is rotated by a motor start signal MS from the control circuit 34, and the revolution number of the motor is set to the double speed of the standard mode by a standard/double speed switching signal KS. Only the odd or the even lines of the picture data are read out to display the picture data at the double speed without changing the number of fundamental clock.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display device for displaying data, documents, etc.

As a conventional display device to which the Kameko photo process is applied, there is Japanese Patent Application Laid-Open No. 56-89166.

These systems do not have a transfer mechanism, but use a laser beam to carve a latent image on an endless photoreceptor belt, which is then visualized using a developer. ,
The present invention is based on the above points and provides a display device whose display speed can be changed according to the user's request.

Further, it is an object of the present invention to provide a display device that can perform display in a desired display mode with a simple device configuration.

That is, the present invention provides a display device that uses an electrophotographic process and is capable of displaying images at different speeds.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross section H of a display device to which the present invention can be applied,
The structure and operation will be explained.

1 contains a memory for storing image information. The output light of a half-Korean laser (not shown) modulated by the image signal output from the memory is scanned in one direction by a scanner 2 and transmitted through a f/θ lens 3 and a mirror 2-4 into a belt-shaped beam. The light is illuminated on the back surface of the photoreceptor 17. Photoreceptor 1
7 is HiC in the direction of the arrow by the rotation of a motor (not shown).
It is a moving material that forms a conductive layer on the surface of a polyethylene terephthalate film using an indium tin oxide fermentation film.
Further, on this conductive layer, OdS with resin as a binder is applied.
It is coated with a photosensitive layer.

The OaS photosensitive layer is made of doped copper and indium and is sensitive to near-infrared light emitted by a semiconductor laser.

Further, a developing device 8 is provided opposite the exposure position of the photoreceptor 17. The developing device 8 is provided with a sleeve 5 having a magnet 6 therein, and the magnet 6 rotates in the direction of arrow F.

The conductive and magnetic developer 7 supplied to the sleeve surface is uniformly regulated by the blade 9 and comes into contact with the photoreceptor surface. Since the width of the area where the developer 7 is in contact with the surface of the photoreceptor is much larger than that of the laser beam, development continues even after the exposure to the laser beam is completed. A DC voltage is applied between the sleeve 5 of the developing device 8 and the base of the photoreceptor 17 by a DC voltage source (not shown).

Rollers 11 and 12 are provided near the positions where exposure and development are performed, thereby keeping the photoreceptor 17 smooth and keeping the distance between the surface of the photoreceptor and the sleeve 5 of the developing device 8 accurate and constant. The toner image formed on the surface of the photoreceptor at a position facing the developing device 8 is sent to the display section 15, and the movement of the photoreceptor 17 is temporarily stopped at this position. In the display section 15, the toner image on the surface of the photoreceptor can be visually observed through the glass 14.

Lamp 16. The lamp 1O has the function of illuminating the surface of the photoreceptor to make the toner image more visible and to erase the history caused by the electric field received during the image forming process.

The lamp 13 is for erasing the history of the photoreceptor, and is turned on only while the belt-shaped photoreceptor is moving, and is turned off when the belt-shaped photoreceptor is stopped.

When changing the displayed content, press the photoconductor 17 again @ (+!+
Then, the photoreceptor having the toner image on its surface is used again. In this case, since the toner image on the surface of the yC drum does not have any adverse effect on the next image formation, there is no need to provide a separate cleaning means, and unnecessary toner images can be erased during the next gap formation.

Reference numeral 18 represents an operation section of the display device d. Reference numeral 19 indicates an optical fiber, and this optical fiber is arranged outside the image writing area and is arranged so that the laser beam is incident thereon. Therefore, each time the scanner 2 scans one line, a laser beam is incident on the optical fiber 19, and by converting this optical signal into an electrical signal, a synchronization signal for each line (c, l) is generated.
Hereinafter, this will be referred to as the BD double signal. ) is obtained. Reference numeral 20 indicates a connector for the original fiber, and reference numeral 21 indicates a control board to which a control circuit, etc., which will be described later, is attached.

FIG. 2 shows a block diagram of the electric circuit in this embodiment.

30 and 31 are memories for storing one page of image data from the outside. 32 indicates a laser drive circuit that blinks the laser 33 according to the vMI image data read out from the memory 30 or 31. 34 is a control circuit of this device, and a display provided on the operation unit 18;
A <-4-to switch (hereinafter referred to as DS8w) 38 and a standard/double speed selection switch 39 are connected. In this embodiment, it is possible to switch between the standard display mode and the double speed display mode by switching the standard/double speed selection switch. Further, the control circuit 34 is connected to a clock oscillator 37 which obtains 1 as a basic clock for reading image data from the memory 30 or 31. 36
is a motor drive circuit that drives the motor 35 that drives the belt-shaped photoreceptor 17, and starts the rotation of the motor 35 by the motor start signal MS from the control circuit 34, and starts the rotation of the motor by the standard/double speed switching signal KS. It has a control function that switches between standard rotation and twice the standard rotation.

In this embodiment, an external device (not shown) that stores image quality information to be displayed is connected to the display device. This external device sends and receives commands to and from the display device using the control OS (command signal), and recognizes the page to be displayed on the display device.

Furthermore, the external device has a function of sending image data of a page to be displayed to the display device.

Now, as shown in FIG. 2, the display device used in this embodiment is a memo IJ (3
0 and 31), and the image data input from the external device is synchronized with the image clock 2 and is processed for each row.
Controlled by a seed control circuit 34, each memo IJK is stored alternately. In other words, memory 30 has odd rows, memory 3
In order to write image data in the form of even-numbered rows, the control circuit V valley 34 controls the write signal lines Wl and W2, respectively.

By the way, when you want to display image data at twice the normal speed (double speed display mode), it is better to display only the image data in the memory that stores odd numbered lines (or even numbered lines). (In this case, the reading speed from the memory is the same as in the standard display mode.) In other words, each row is thinned out.

FIG. 3 is a control flowchart in this implementation, and FIG. 4 is a timing chart when doubling the image display speed. Below, FIGS. 3 and 4 will be explained.

In step 1 in FIG. 3, the display device is put into an operable state. Here, for example, when the laser 33 reaches a predetermined temperature, the scanner 2 is controlled to rotate at a predetermined speed. Thereafter, the process moves to step 2, where commands are exchanged with the external device and the external device k is made to recognize the image data (including the number of pages) to be displayed. After that, the process moves to step 3, and it is determined whether or not the DSSW has been pressed by the user.

If DSSW is pressed here, move to step 4,
Determine whether the current mode is standard display mode or double speed display mode. If it is the standard display mode, the process moves to step 5, and the υ motor 35 is rotated at the standard speed using the motor start signal MS and the standard/double speed switching signal KS. Then, in step 6, the 1III image data is displayed and synchronized to the image clock 2 and alternately stored in the memory 30.3 for each row.
Enter 1.

Image clock 2 sends address data from address lines 1 and 2 to memory 3o in synchronization with image data.
, 31 to use human power.

When all the image data to be displayed has been input to the memories 30, 31, the process moves to step 7, where the image data input manually to the memories 30, 31 is read out and outputted alternately row by row by controlling the signal line RIFR2. Further, the output image data is visualized by the aforementioned developing device 8. 1
After displaying one page of image data, the motor is stopped, and in step 8 it is determined whether a predetermined number of pages have been displayed. If the predetermined number of pages have not been displayed, the process returns to step 5 to restart the motor and repeat the operations from step 6 to step 7 described above.

If the current mode is the double speed display mode in step 4, then in step 9 the rotational speed of the motor 35 is made twice that of the standard display mode. And in Stella 10, S□
Perform the same operation as step 6, and when the image data to be displayed is input to the memo IJ 30, 31, step 11
Move to. In step 11, image data only from the memory 30 is synchronized with 1 to the basic clock and output. Further, the output image data is visualized by the developing device 8, and the above operations are repeated until all of the image data 2 input to the memory 30 is output. When one page of image data has been displayed, the motor is stopped, and in step 12 it is determined whether or not a predetermined page of image data has been displayed.

If the predetermined number of pages have not been displayed, the process returns to step 9 and the same operation as described above is repeated.

FIG. 4 is a timing chart when the image display speed is doubled in this embodiment. First, it is assumed that the user presses the parrot/multiply 11 selection switch 39 on the operation unit 18 and selects the double speed display mode.

Thereafter, when the user presses the DSSW, the motor 35 that drives the belt-shaped photoreceptor 17 will rotate twice as fast as the standard display speed. The photoreceptor 17, which is shaped like a cylindrical belt, moves at twice the speed of the standard display speed.

Further, after the rotation of the motor 35 is started and the image data to be skipped has been inputted from the external device, the 17+ii image display is started. Here, in order to synchronize the scanning of each line of the image with the image data, the BD multiplied signal detected by the source fiber 19 is used.

After a certain period of time (T) after the pBp signal is detected, the image data of each image line is read out from one of the memories. Now, in the double-speed display mode in this embodiment, the belt-shaped photoreceptor 17 is moved at twice the moving speed in the standard display mode, so that images of the same size can be displayed at twice the standard display speed. To display at twice the speed,
A method is used to thin out each line. As shown in the image data in Figure 4, after the nth row of image data is read from the memory, the next image data is n+
The image data on the second line is output.

As a result, as shown in Fig. 5, the display area for one page is the same in the standard display mode and the double-speed display mode, but in the double-speed display mode, the belt-shaped photoreceptor is Since the movement speed is twice that of the standard display mode,
Double display speed is possible.

In the non-example, the rotational speed of the motor was twice that of the standard display mode in the double-speed display mode, but if the rotational speed of the motor is not changed, the entire rotation speed in the direction of belt movement is Images can be obtained in compressed form. In addition, the control circuit 34 in FIG. 2 controls the address line 1.2 and the write signal mW11 so that the image data input from the external device is input to the page memory 30.31 alternately row by row.
W2 is controlled, but when the image data input from the external device is sequentially input to the page memory 30.31 and read out, the address 2 in 112 Ij and the readout signal lines R1 and R2 are controlled to read out the odd numbered rows (even numbered rows). It is also possible to extract only the image data of . Further, in this embodiment, the memos IJ 30 and 31 are capable of storing one page of image data, but they may be capable of storing a predetermined number of pages.

As explained above, according to this embodiment, only the odd-numbered lines (or even-numbered lines) of the image data are read out, so - 1- The image data can be displayed faster than usual without changing the frequency of the basic clock for reading out the image data. I can do it. Therefore, images can be quickly searched according to the user's convenience.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a display device in which the present invention can be clearly understood, ff1
Figure 2 is an electric circuit block diagram in this embodiment, and Figures 3 and 4 are
4 is a control flowchart in this embodiment, FIG. 4 is a timing chart of double speed display mode, and FIG. 5 is a diagram showing display images in standard display mode and double speed display mode. Here, 2 is a scanner, 8 is a developer, 17 is a photoreceptor, 3
0.31 is page memory, 321 is laser drive circuit, 3
4 is a control circuit, 36 is a motor drive circuit, and 37 is a basic clock oscillator. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] A display device that uses an electrophotographic process and is characterized in that it displays images at different speeds.