JP2000036909A - Electronic blackboard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record image information written on a hand-written face with same quality at all times without being affected by a light source and a pen or the like by optionally selecting a threshold level read by a read section. SOLUTION: An operation section starts operation and applies initial setting to recording operation in response to respective modes. A switch 20 provided on a main control board is used to select a concerned threshold table among a plurality of threshold tables stored in a ROM 16 where threshold levels are differed stepwise and a threshold level in response to a density selected by a read density key is read from the threshold table selected by the switch 20 and set it to a gate array 17. After the end of the setting, recording by a printer is executed. Since a threshold level is switched optionally and selected, information is recorded with same quality at all times and the threshold level in response to the density is selected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic blackboard apparatus which conveys an endless screen sheet having a plurality of writing surfaces which can be written and erased by hand, reads image information, and records it on paper.

[0002]

2. Description of the Related Art In reading an image drawn on a screen sheet as an electric signal, it is necessary to set a threshold level. In a conventional electronic blackboard device, only one type of threshold level is written in a ROM. Was.

[0003]

Therefore, when a fluorescent lamp as a light source or an attached or commercially available pen for writing is new, the image information to be recorded is inevitably thin, resulting in a print result of the same quality. Was not obtained.

Therefore, the present invention prepares a plurality of threshold levels to be read, and arbitrarily switches and selects the threshold levels so that the image information written on the handwritten surface can always be obtained with the same quality without being affected by a light source or a pen. The purpose is to enable recording on paper.

[0005]

The electronic blackboard device of the present invention is characterized in that it comprises a threshold level switching means for arbitrarily switching and selecting a threshold level to be read in the reading section. The threshold level switching means preferably has the following configuration.

[0006] The threshold level switching means selects an arbitrary threshold level from a threshold table in which the threshold levels are gradually changed.

[0007] The threshold level switching means comprises a plurality of threshold tables in which the threshold levels are varied stepwise, and a switch for selecting the threshold table, and a read density key is selected from the threshold tables selected by the switch. Select a threshold level according to the selected density.

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of an electronic blackboard device according to the present invention, FIG. 2 is a cross-sectional view when the screen sheet has two writing surfaces, and FIG. 3 is a cross-sectional view when it has four writing surfaces.

In FIG. 1, an opening 3 for exposing a writing surface of a screen sheet 2 one by one is provided in a blackboard main body 1, and an operation unit 4 is provided on one side of the opening 3.

In FIG. 2, a screen board 5 is provided inside the opening 3 so that a screen sheet 2 is provided.
Is transported along the front surface of the screen board 5 in the opening 3. The screen sheet 2 is wound around a driving roller 6 and a driven roller 7 disposed at both ends of the screen board 5 in the blackboard main body 1.
Although not shown, a sheet tension mechanism is provided for the driven roller 7, and a sheet transport motor as a driving source is provided for the driving roller 6.

On the back side of the screen board 5, there are a light source 8, a mirror 9 and a lens 10 as an optical system for reading image information on a writing surface of the screen sheet 2, and a CCD 11 as an optical / electrical converter. A reading unit 12 is provided. In addition, although not shown, the blackboard main body 1 is provided with a printer, a power supply unit, and the like that record information read by the reading unit 12 on a sheet.

The screen sheet 2 is conveyed in the direction of arrow a in FIG.
In step 2, the signal is read as an electric signal, processed by the CPU, and recorded on paper by the printer.

In FIG. 3, driven rollers 13 and 14 for guiding the screen sheet 2 are added to the structure of FIG. 2 in order to make the writing surface of the screen sheet 2 four.

FIG. 4 shows an electrical schematic configuration. CPU
15 controls the whole according to a program stored in a ROM (read only memory) 16. CPU
A RAM 15 processes read data read by the reading unit 12 and digitized by the gate array 17, and
(Random access memory) 18 and the printer 1
Record on paper at 9.

FIG. 5 shows an example of a configuration on a main control board for controlling the entire electronic blackboard. CPU15,
In addition to the ROM 16, the gate array 17, and the RAM 18, R
A switch 20 for selecting a threshold table stored in the OM 16 is mounted. As the ROM 16,
In this example, an erasable and programmable read only memory (EPROM) is used.
-only Memory).

FIG. 6 is an operation flowchart at the start of recording. When a copy mode key or a reading density key (not shown) is operated on the operation unit 4, each initial setting of the recording operation according to each mode is performed (Step S).
1). Thereafter, whether the switch 20 shown in FIG. 5 is set to “1” (step S2), is set to “2” (step S3), is set to “3” (step S4), It is determined sequentially.

When the switch 20 is set to "1", the first threshold table stored in the ROM 16 is selected, and the reading density key is set to "dark".
According to which of “normal” and “light” is set, a threshold level corresponding to the setting is read from the first threshold table and set in the gate array 17 (step S5).

When the switch 20 is set to "2", the second threshold table stored in the ROM 16 is selected, and the reading density key is set to "dark".
According to which of “normal” and “light” is set, a threshold level corresponding to the setting is read from the second threshold table and set in the gate array 17 (step S6).

If the switch 20 is set to "3", the third threshold table stored in the ROM 16 is selected, and the reading density key is set to "dark".
In accordance with the setting of “normal” or “light”, a threshold level corresponding to the setting is read from the third threshold table and set in the gate array 17 (step S7).

If the switch 20 is set to "4" (NO in any of steps 2, 3, and 4),
The fourth threshold table stored in the ROM 16 is selected, and the reading density key is set to “dark”, “normal”,
According to which of “thin” is set, a threshold level corresponding to that is read from the fourth threshold table and set in the gate array 17 (step S8).

After the setting of the threshold level is completed in any of steps S5, S6, S7 and S8, the recording operation by the printer 19 is executed (step S5).
9).

[0023]

According to the first aspect of the present invention, the threshold level to be read by the reading unit can be arbitrarily switched and selected, so that the image information written on the handwritten surface is always the same without being affected by the light source or the pen. Record on paper with high quality.

According to the second aspect of the present invention, an arbitrary threshold level can be selected from a threshold table in which threshold levels are gradually changed, so that the threshold level can be easily set.

According to the third aspect of the present invention, the threshold level corresponding to the density selected by the reading density key can be selected from the threshold table selected by the switch, so that recording can be performed while securing a constant recording quality. The concentration can be selected.

[Brief description of the drawings]

FIG. 1 is a front view of an electronic blackboard device according to the present invention.

FIG. 2 is a transverse cross-sectional view when a screen sheet has two writing surfaces.

FIG. 3 is a cross-sectional view of a screen sheet having four writing surfaces.

FIG. 4 is a block diagram showing an electrical schematic configuration.

FIG. 5 is a block diagram showing a configuration example on a main control board.

FIG. 6 is a flowchart of an operation example.

[Explanation of symbols]

 2 screen sheet 4 operation unit 12 reading unit 15 CPU 16 ROM 17 gate array 18 RAM 19 printer 20 switch

Claims (3)

[Claims] 1. A sheet transport unit for transporting a screen sheet having a plurality of writing surfaces that can be written and erased by hand, a reading unit that reads image information written on the writing surface of the screen sheet, and information related to the reading. An electronic blackboard apparatus comprising: a recording unit for recording on a sheet; and a threshold level switching unit for arbitrarily switching and selecting a threshold level to be read by the reading unit. 2. The electronic whiteboard apparatus according to claim 1, wherein the threshold level switching means selects an arbitrary threshold level from a threshold table in which the threshold levels are changed stepwise. 3. The threshold level switching means comprises a plurality of threshold tables in which threshold levels are changed stepwise, and a switch for selecting the threshold table. The threshold value is selected from among the threshold tables selected by the switch. 3. The electronic blackboard device according to claim 2, wherein a threshold level corresponding to the density selected by the key is selected.