JPS61130098A - Electronic blackboard - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an electronic blackboard used as an automatic meeting minutes creation device or the like.

BACKGROUND TECHNOLOGY In general, this type of electronic blackboard has a plurality of pages of writeable and erasable writing surfaces provided in the whiteboard, and the written surface is moved and the writing surface is exposed to fluorescent light or the like. The image reflected light from the writing surface is transferred to a photoelectric conversion element, such as a CCD image sensor, through a mirror, lens, etc.
The device forms an image on the writing surface and reads the image information on the writing surface. It is possible to obtain a hard copy by feeding the read image information to a printer.

In such electronic blackboards, problems such as the light source not lighting up (including a decrease in the amount of light due to deterioration), defects in the CCD image sensor, etc., misalignment of the optical system (light source - lens - image sensor), r) RAM (dynamic RAM) ) or other defects, image information may be missing, making it impossible to obtain a normal hard copy. In this regard, conventionally, the light from the light source is detected by a sensor, and only an abnormality in which the light source is not lit is detected. Therefore,
Even if an abnormality other than the light source is not turned on occurs, this cannot be detected and the copy will be made without the abnormality.

Purpose The present invention was made in view of the above points, and an object of the present invention is to provide an electronic blackboard that can detect various abnormalities in advance and does not operate with abnormalities.

Structure: In order to achieve the object described in item 1, the present invention provides a sheet that can be freely written on and erased. 2. A plurality of writing surfaces formed on a sheet,
a means for moving the sheet; a reading means for exposing and scanning the writing surface on the moved sheet 1 to read the contents;
In the electronic blackboard, the electronic whiteboard is equipped with a means for printing the contents of the read writing surface, and an initializing means for setting the sheet at a basic position after turning on the power, and exposing and scanning a non-image position of the initialized sheet I. The apparatus is characterized in that it is provided with the reading means, means for counting the number of black level data of the read image data, and means for detecting the presence or absence of an abnormality based on the counted number of black level data. It is something.

A first embodiment of the present invention will be described below with reference to FIGS. 1-10. First, Figure 1 shows the basic configuration of an electronic blackboard, which is formed in a rectangular shape and has an opening 1a on the front.
A roll-up type whiteboard 1 to 2 is provided in a blackboard main body 1 having a main body 1.

The front surface of this white sheet 2 is a writing surface 3 that can be freely written on and erased, and four to five pages of such writing surfaces 3 are prepared in white sheets 1 and 2.

Both ends of such Why I and Sea 1 and 2 are connected to rollers 4 and 4, respectively.
−． It is wound around drive rollers 8, 9 via rollers 5, 6, and 7. These drive ports 8 and 9 are connected to a pulse motor 10.
, 11, which is rotatably driven in forward and reverse directions.
As a result, the writing surface 3 of the white I to the sheet 2 is sequentially moved. Here, a back plate 12 is provided on the back surface of the white sheet 2 at the opening 18 portion. This white sheet 2 is usually wound to the left,
A reading means 13 for exposing and scanning the writing surface 3 is provided at a position A after passing the roller 5. The writing surface 3 is integrally exposed to slit light using a fluorescent lamp 14, and the reflected light is imaged on a photoelectric conversion element such as a CCD 17 via a mirror 15 and a lens 16 and read.

The image information on the writing surface 3 read by the CCD 17 in this manner is printed by a printing means such as a thermal printer (not shown).

Here, FIG. 2 shows the white sheets 1 and 2 expanded, and in this embodiment, five pages of writing surface 3 are prepared as P□ to P5, but the fifth page P5 is exposure position A
Since it is not possible to wind up and move up to the 5th page P.
The contents of writing surface 3 in 5 cannot be hard-copied. Therefore, only the contents of the writing surfaces 3 of P1 to P4 can be copied.

A detection hole 18 for page identification is formed in the second part of each writing surface 3 of the white sheet 2, located on the previous page side, and a transmission type sensor 1 is formed when passing through the left end of the opening 1a.
It is set to be detected by 9. Here, in this embodiment, the detection hole 1.8a for page 1 P1 is different from the other summer detection holes 18b to 18e, and is formed by two holes and is distinguished from the others. . This is to search for the first page P1 on the writing surface 3 and set the white sheet 2 at the basic position during initialization when the power is turned on.

Next, the entire control circuit will be explained with reference to FIG.

First, a direct memory access controller 1 to a roller DMA 21 are connected to a CPU 20 which is the central part of control. On the other hand, such CPU20 and DMA21
ROM22, RAM23, and timer 2 are controlled by address bus AB, data bus DB, and control bus CB.
4 is connected, and furthermore, CCD 1.7, thermal head 2
5. A dynamic RAM DRAM 26 is also connected through each controller 27, 28, and 29. Therefore, the DMA 21 DRs both data from the CCD 17.
In addition to transmitting directly to AM, 26 (see Figure 4),
Data is directly transmitted from this DRAM 26 to the thermal head 25 (see FIG. 5). Further, I10 ports 1-30 are connected to the CPU 20, and these ■/○ ports 1-30 are connected to a fluorescent lamp controller 31 for controlling the fluorescent lamp 14, an operation section 32, and the pulse motor 1.
0, 11, and a pulse motor driver 34 for a pulse motor 33 that transports thermal paper for copying.

Here, a specific configuration of the CCD controller 27 is shown in FIG. Both data read by the CCD 17 from the writing surface 3 are first amplified by an amplifier 35, A/D converted by an A/D conversion circuit 36, image processed by an image processing circuit 37, and binarized by a digital comparator 38. After that, the serial/parallel conversion circuit 39 converts it into an 8-bit parallel signal, and sends it to the DRA, M2.
6 is output. In this way, the image data from the CCD 17 is directly stored in the DRA and M26 under the control of the DMA 21. An abnormality detection circuit 40 is provided to which the binary image signal from the digital comparator 38 is input. FIG. 8 shows the configuration of this abnormality detection circuit 40.

First, a D-type flip-flop 41 is provided, to which, together with a clock signal C, a signal of an effective pixel signal a and pixel data b via an ○R gate 42 is input. Here, the white level of pixel data b is the white level (ground level)
, and the white level indicates the thought level. The output d from the flip-flop 41 is input to the OR gate 1 via 43 to the counter 44 together with the effective pixel signal a.

The output Q (signal e) of this counter 44 is input to the CPU 20. Here, the value of the output Q of the counter 44 is
It is determined by the number of binarized image data obtained by exposure scanning for abnormality detection. In this embodiment, the exposure scan for abnormality detection is one line scan;
, the number of CCD effective pixels of the line is 1260. Therefore, in consideration of erroneous reception of binarized image data due to noise etc., the safety factor D is set to 10, and 1260-10 = 1250.
The 1-value of the counter 44 is set to . That is,
When the counter 44 changes the clock signal C to 1-250 counter 1, the output Q becomes the [■] level.

In such a configuration, the abnormality detection operation according to this embodiment will be explained with reference to FIG. 9 and timing chart 1 in FIG. First, when the power is turned on, initialization is performed to set the white sea 1-2 to the basic position. That is, the sensor 19 detects the detection holes 18a to 18e on each writing surface 3, and the first page P
The sheet 2 is moved to the why 1 until the sheet 1 reaches the opening 1a. At this time, since the detection hole 18a for the first page P1 is different from the other detection holes 18b to 18e, the first page P,
The cue will be displayed. In this way, when the white sheet 2 is initialized to its basic position, that is, when the writing surface 3 of the first page P1 is located, the B line of the white sheet 2 (see Figure 2) is exposed to the exposure in Figure 1. It will be located at position A. Since this B line position is a non-image position outside the writing surface on the white sheet 2, it is always the background portion (white level) of the white sheet 2.

In this state, the B line position is exposed and illuminated by the fluorescent lamp 14, and the image data CCD1 at the B line position is
Read by 7. The read image data is converted into binary image data in the CCD controller 27. Therefore, if the pixel data b is at the white level, it will be at the ■ (level), and if it is at the black level, it will be at the white level.Here, the effective pixel signal a is at the white level when the effective pixel data is output, and the effective pixel data At times other than when outputting, it is at a white level and resets the counter 44 to 1.Clock signal C is a control clock for controlling the CCD.

The signal d allows the pixel data b to be output when the clock signal C rises. Signal e is 2 of counter 44
When the value of the digitized image data reaches 1250, it becomes a white level and becomes an interrupt input to the CPU 20. Therefore, if the binarized image data at the non-image position B is correctly read as a white level (white level) at its background level, and if the pixel data remains at the level I (as shown in FIG. 9), the counter 44 The count l~ value does not increase, and the count value becomes approximately O over one line of 1260 pixels of the CCD 17.

As a result, the counter 44 does not produce an output and becomes normal, and the CPU 20 is not interrupted due to an abnormality.

On the other hand, even when reading image data at non-image position B, the first
As shown in FIG. 0, when the black level is determined and the pixel data reaches the L level, the value of the counter 44 advances.
It may exceed 125o.

When the callan I value exceeds 1250, an abnormality occurs, and an output Q is output from the counter 44, interrupting the CPU 20, and abnormality processing is performed.

Here, the binary image data of the image data at the non-image position B becomes black level in various cases such as when the fluorescent lamp 14 is not lit, when the CCD 17 is defective, when the DRAM 26 etc. are defective. Therefore, according to this embodiment, it is possible to reliably detect not only the failure of the fluorescent lamp 4 but also various other abnormalities. When such an abnormality is detected, the abnormality processing may be performed. Therefore, it is possible to prevent a copy operation from being performed while there is an abnormality in the C0D17 or the like.

Next, a second embodiment of the present invention will be described with reference to FIGS. 11 to 14. In this embodiment, the CCD controller 27
This is a modified version of the abnormality detection circuit 45 connected to the digital comparator 38, and mainly includes a parallel counter 46.

An effective pixel signal a is input to this parallel counter 46, and pixel data b inverted by an inverter 47 and a clock signal C are input via an AND gate 1-48.

In such a configuration, the parallel counter 46 counts pixel data at the black level as the number of input data progresses, and as shown in FIG. 12, when it is normal, it is at the white level, so the count value does not increase. . On the other hand, the first
As shown in FIG. 3, if the image data at the non-image position B is determined to be at the black level, the count value increases. Then, exposure scan for one line at non-image position B (number of pixels 12
60) is completed, the count value g of the parallel counter 46 is input to the CPU 20 via the machine/circle board 1-30, and the CPU 20 determines whether or not there is an abnormality based on the count value g. The flow-11 chart in FIG. 14 shows such an abnormality detection operation.

Effects The present invention focuses on the fact that, as described above, there is a non-image position at the background level located outside the writing surface on the sheet I. After the power is turned on, the sheet is initialized and this non-image position is exposed and scanned. , the number of black level data of the image data is counted, and the presence or absence of an abnormality is detected based on this number of black level data, so it is possible to reliably detect not only the abnormality of the exposure light source not turning on, but also the occurrence of various abnormalities. Therefore, it can be used under normal conditions.

[Brief explanation of the drawing]

Figures 1 to 10 show an embodiment of the present invention, in which Figure 1 is a plan view showing a schematic configuration of an electronic blackboard, Figure 2 is a front view showing a white sheet unfolded, and Figure 3 is a block diagram showing the overall circuit configuration, Figures 4 to 6 are block diagrams showing part of the signal exchange, Figure 7 is a block diagram showing image data processing, and Figure 8 is an abnormality detection circuit. FIG. 9 is a timing chart in normal conditions, and FIG. 10 is a timing chart in abnormal conditions.
1. FIGS. 11 to 14 show a second embodiment of the present invention, and FIG. 11 is a block diagram of the abnormality detection circuit, and FIG.
FIG. 2 is a timing chart during normal operation, FIG. 13 is a timing chart during abnormal operation, and FIG. 14 is a flowchart showing abnormality detection operation. 2... White sheet, 3... Writing surface, 13...
Reading means, 18a...Detection hole, 19...Sensor, 2°...CPU, 40...Counter, 46...
Parallel counter, B...non-image position

Claims (1)

[Claims] A plurality of writing surfaces formed on a sheet that can be freely written on and erased, a means for moving the sheet, a reading means for exposing and scanning the writing surfaces on the moved sheet to read the contents, and a writing surface that has been read. In the electronic blackboard, the electronic whiteboard is provided with: an initializing means for setting the sheet in a basic position after power is turned on; a reading means for exposing and scanning a non-image position of the initialized sheet; An electronic whiteboard comprising: a counting means for counting the number of black level data of the octopus image data; and a means for detecting the presence or absence of an abnormality based on the counted number of black level data.