JP2000301887A - Electronic white board device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic white board device, with which a copying with the same copying density has that, which is obtained in the copying of an image information written on a writing surface with a black marker pen only, even when the image information is written on the writing surface with a red, a blue or the like marker pens including the black marker pen, can be realized, which is low in cost, and, in addition, the rise time of which is short. SOLUTION: In a light emitted from a fluorescent lamp 25, which is incident upon the writing surface S of a conveyable screen sheet 15, reflects on the writing surface S so as to be incident upon a CCD 28 in order to read the image information on the writing surface S with an optical reading part 14, a monochromatic filter 2, which passes only the monochromatic wavelength of the light or a band filter 3, which removes the wavelength in the infrared region of the light, is arranged in an optical path ranging from the fluorescent lamp 25 to the CCD 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic blackboard device for conveying image data handwritten on a writing surface, reading the image information by an optical reading section, and recording the information on a sheet.

[0002]

2. Description of the Related Art Conventionally, when an electronic blackboard device is used, for example, a marker pen is used as a writing tool, and an alcohol-based ink is applied to a writing surface with the marker pen to write characters and figures.

When making a copy of the written content, the user operates a copy switch on an operation panel to read the written content with a CCD of an optical reading unit in the apparatus. Then, the recording paper is discharged while recording the information on the paper stored in the printer.

[0004]

In the above-described conventional electronic blackboard device, when copying image information written on a writing surface onto a recording sheet, there are the following two problems regarding the copy quality.

One is that when image information is written on a writing surface using a black marker pen and a color marker pen such as red or blue, the image information is written in color as compared to the portion written in black. The copy density on a portion of the recording paper was considerably reduced, making it difficult to read.

[0006] This is because when the object color on the writing surface (the ink color of the marker pen) is different, it is reflected there and reflected on the CC.
Output of the CCD for light incident on D, ie, CC
This is because D has different sensitivity characteristics.

That is, in the case of an object color relating to a band with low sensitivity in a CCD, the read image information becomes a copy having a low density as it is. On the other hand, the object color related to the band having high sensitivity is a copy having a clear density.

In order to solve this problem, a method of coloring the surface of a fluorescent lamp or a lens in green is known.

FIG. 8 is a graph showing the object color of the writing surface and the sensitivity characteristics of the CCD. The horizontal axis represents the wavelength of light. Further, a curve a in the figure is a condition under which the surface of the fluorescent lamp or the lens is not colored green, and a curve b is a condition under which the surface is colored green.

As described above, when the surface of the fluorescent lamp or the lens is colored green, for example, red (wavelength of about 650 nm) and blue (wavelength of about 480 nm) other than green (wavelength of about 530 nm) are not included in the CCD. High sensitivity and a clear density copy can be obtained.

However, as shown in the figure, when the surface of the fluorescent lamp or the lens is colored green, the CCD sensitivity is deteriorated only when the object color is green. However, a clear copy cannot be obtained for green. In addition, coloring the surface of the fluorescent lamp or the lens in green color is considerably costly, and replacing the fluorescent lamp or the lens with an uncolored fluorescent lamp or lens requires a lot of trouble.

Another problem is that immediately after the power of the electronic blackboard device is turned on, in an unstable state where the temperature of the fluorescent lamp is not sufficiently raised, as shown in FIG. This is due to the generation of light.

When the output of the CCD is adjusted while the light incident on the CCD is unstable as described above, when the temperature of the fluorescent lamp rises and approaches a stable state, the CC
The output of D is lower. When a copy was made in this state, the copy density was considerably increased, making it difficult to read.

In order to solve this problem, the output of the CCD is not adjusted until the temperature of the fluorescent lamp rises to a stable state, and after the fluorescent lamp stably emits no light in the infrared region, The CCD output was adjusted to enable copying. However, the waiting time during that time significantly reduces the workability of the electronic blackboard device.

Therefore, the present invention provides a method for writing image information on a writing surface using a black marker pen as well as a color marker pen such as red or blue in the same way as the case where only black is used. It is an object of the present invention to provide an electronic blackboard device which can be copied at a low cost and has a short startup time.

[0016]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. That is, when the reference numerals in the attached drawings are added in parentheses, the present invention provides:
The light emitted from the fluorescent lamp (25) is incident on the writing surface (S) of the transportable screen sheet (15), and the light reflected on the writing surface (S) is incident on the CCD (28) to be written on the writing surface (S). In an electronic blackboard device having an optical reading section (14) for reading the image information of (S), a CCD (Central Processing Unit)
An electronic blackboard device characterized in that a monochromatic filter (2) that transmits only a monochromatic wavelength of light is arranged in an optical path reaching (28).

In this case, it is preferable that the monochromatic filter (2) is movably installed outside the optical path.

Further, according to the present invention, the light emitted from the fluorescent lamp (25) is incident on the writing surface (S) of the screen sheet (15) capable of being conveyed, and the light reflected on the writing surface (S) is reflected by the CCD.
(28) In an electronic blackboard device having an optical reading section (14) for reading image information of the writing surface (S) by being incident on the writing surface (S), light is transmitted through an optical path from the fluorescent lamp (25) to the CCD (28). An electronic blackboard device comprising a bandpass filter (3) for removing a wavelength in an infrared region.

In these inventions, the aperture stop (1) is provided in the optical path, and the monochromatic filter (2) or the bandpass filter (3) can be fixed to the aperture stop (1).

[0020]

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

FIG. 6 is an external perspective view of an electronic blackboard device according to the present invention, and FIG. 1 is a diagram showing an outline of the internal mechanism as viewed from above.

This electronic blackboard device, as shown in FIG.
A slightly horizontal rectangular flat blackboard body 10 is movably supported by a stand 11 with casters.

The blackboard main body 10 has a front window 13a on its front side.
Is provided, and a part of a screen sheet 15 to be described later is exposed from the front window 13a to form a writing surface S there.

On the blackboard main body 10, an operation panel 16 provided with a copy switch or the like is provided on one side edge of the window frame 13, and an elongated pen tray 17 is provided along the lower edge of the window frame 13. Further, a printer 18 is attached to the lower right side of the blackboard main body 10.

As shown in FIG. 1, the main body 10 of the blackboard is provided with a drive roller 20 and driven rollers 21 to 23 on both right and left sides thereof, and these roller shafts are rotatable by upper and lower frames (not shown). To support. In addition, roller 20
An endless screen sheet 15 is stretched between the upper and lower frames 21, the writing surface S is backed by a back plate 24, and the whole is supported by a rectangular frame-shaped base frame 12.

Further, the blackboard main body 10 is provided with an optical reading section 14 behind the screen sheet 15. The optical reading unit 14 includes a fluorescent lamp 25, a mirror 26, a monochromatic filter 2,
Aperture stop 1, bandpass filter 3, lens 27, CCD 28
And so on.

Here, the aperture stop 1 is disposed at the front focal position of the lens 27. As shown in FIG. 5, the aperture stop 1 has an opening 1a and a screw hole 1c in a frame 1b. Then, a screw is inserted into the screw hole 1c and fastened to a frame (not shown) in the blackboard main body 10.

The shape of the opening 1a is a curved shape that gradually spreads from the center to both ends in order to correct the light intensity distribution characteristics in the longitudinal direction of the fluorescent lamp and to make the light flux uniform.

On the other hand, the monochromatic filter 2 is, for example, a green filter that transmits only a green wavelength, and is disposed closer to the fluorescent lamp 25 than the aperture stop 1. Monochromatic filter 2
As shown in FIG. 3, the filter unit 2 is mounted on the frame unit 1b.
a.

One end of the monochromatic filter 2 is supported by a support shaft 6 as shown in FIG.
It can be rotated around. A wire 5b is attached to one end of the other side.
Is connected to the iron core portion 5a. Then, when the user arbitrarily operates a selection switch (not shown) on the operation panel 16, as shown in FIG. 2, the iron core 5 a of the solenoid 5 operates, and the monochromatic filter 2 rotates about the support shaft 6. Move out of the optical path.

The filter portion 2a of the monochromatic filter 2 transmits only the specific color. Then, the light of other wavelengths is not transmitted, and the sensitivity of the CCD 28 is improved for such light. Therefore, when the single-color filter is a green filter, image information written in red, blue, or the like other than green becomes a clear copy, like image information written in black.

On the other hand, the bandpass filter 3 is, for example, an infrared cutoff filter that removes infrared rays and transmits only wavelengths in the visible region, and is disposed closer to the CCD 28 than the aperture stop 1. As shown in FIG. 4, the bandpass filter 3 is formed by attaching a filter portion 3a to a frame portion 3b having a screw hole 3c. Then, insert a screw into the screw hole 3c,
Fastened to a frame (not shown) in the blackboard body 10.

The light transmitted through the filter portion 3a of the bandpass filter 3 has a wavelength in the infrared region removed, and only light having other wavelengths enters the CCD 28.

When the above-described electronic blackboard device is used, a marker pen is used as a writing tool, and the alcohol-based ink is applied to the writing surface S with the marker pen to write characters and figures.

When making a copy of written contents using a black marker pen or a red or blue marker pen other than green, for example, the copy switch on the operation panel 16 is operated as shown in FIGS. The screen sheet 15 is conveyed while the drive roller 20 is rotated by driving a drive motor (not shown) and the driven rollers 21 to 23 are driven to rotate.

Then, the screen sheet 15 is irradiated with light from the fluorescent lamp 25 of the optical reading unit 14 and the reflected light is reflected by the mirror 26, and the monochromatic filter 2, the aperture stop 1, the bandpass filter 3, and the lens 27 The transmitted light forms an image on the CCD 28 to read the written contents. And CCD28
Then, the electrical signal after photoelectric conversion is transferred to the printer 18 and the recorded content is scaled and recorded on paper stored in the printer 18 while discharging the recording paper.

On the other hand, when erasing the written contents, the writing surface S is wiped with an eraser (not shown) to erase the written contents.

On the other hand, when making a copy of the written contents using the green marker pen, first, the selection switch on the operation panel 16 is operated. When the selection switch is operated, the above-described monochrome filter 2 moves out of the optical path as shown in FIG.

Thereafter, the copy switch on the operation panel 16 is operated in the same manner as during normal copying. Then,
The moved screen sheet 15 is irradiated with light from the fluorescent lamp 25 of the optical reading unit 14, the reflected light is reflected by the mirror 26, passes through the aperture stop 1, the bandpass filter 3, and the lens 27, and forms on the CCD 28. Image and read the written content. Then, the recording paper that records the read content is
The paper is discharged from the printer 18.

At this time, in order to clearly identify the green color for the white portion on the writing surface S, that is, the CCD for the green color
The output of the CCD 28 is adjusted in order to increase the sensitivity of reading the data.

In the illustrated example, the monochromatic filter 2 is disposed closer to the fluorescent lamp 25 than the aperture stop 1 and the bandpass filter 3 is disposed.
Is arranged closer to the CCD 28 than the aperture stop 3, but both filters may be arranged anywhere in the optical path from the fluorescent lamp 25 to the CCD 28.

In the illustrated example, the monochromatic filter 2
Alternatively, although the bandpass filter 3 is provided separately from the aperture stop 3, they may be fixed to the aperture stop 3 as shown in FIG. For example, in the integrated filter 8 shown in FIG. 7, a band-pass filter is stuck on a monochromatic filter provided with a screw hole 8c, and a light-shielding portion 8b is formed thereon to form an opening 8a as an aperture stop. Is provided. The integrated filter 8 is disposed at a front focal position of the lens 27.

In the illustrated example, one single-color filter 2 that can be inserted and removed in the optical path is provided so that clear writing is possible when writing is performed on the writing surface S using only a specific color (for example, green). For this purpose, the output of the CCD 28 is adjusted at the same time when the monochromatic filter 2 is moved out of the optical path.

On the other hand, the first monochromatic filter 2
A second monochromatic filter that transmits a specific color (for example, red) different from that of the first monochromatic filter is provided in the optical path so that the second monochromatic filter can be inserted into and removed from the optical path. With the moving configuration, a clear copy can be made even for image information written in green and colors other than red including black.

In the illustrated example, the fluorescent lamp 25 is used as the light source of the optical reading unit 14. However, a light source other than the fluorescent lamp 25 may be used as long as it emits visible light.

[0046]

According to the first aspect of the present invention, since a monochromatic filter that transmits only a specific monochromatic wavelength is arranged in the optical path from the fluorescent lamp to the CCD, the specific color can be obtained by a simple mechanism. The image information of the writing surface written using a marker pen of a color other than that can be detected with high sensitivity on the CCD together with the image information written by the black marker pen, and is the same as when only black is used. It is possible to provide an inexpensive electronic blackboard device capable of performing copying at a clear copy density of the order.

According to the second aspect of the present invention, since the monochromatic filter is movably disposed outside the optical path of the optical reading section, the image of the writing surface written using only the marker pen of the specific color concerned is provided. Even when information is copied, it is possible to provide an electronic blackboard device capable of selectively moving the single-color filter out of the optical path, detecting it with good sensitivity on the CCD, and copying at a clear copy density.

According to the third aspect of the present invention, since the bandpass filter for removing the wavelength in the infrared region is arranged in the optical path from the fluorescent lamp to the CCD, the infrared light generated immediately after the fluorescent lamp is started can be easily reduced. It is possible to adjust the output of the CCD without providing a standby time until the fluorescent lamp is stabilized, and to provide an electronic blackboard device with a short start-up time and a clear copy quality.

According to the fourth aspect of the present invention, since the aperture stop, the monochromatic filter, and the bandpass filter are integrally formed, the image information written with the color marker pen is copied at an appropriate density. An electronic blackboard device with a short rise time and a small number of components can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an internal mechanism of a blackboard body of the present invention as viewed from above.

FIG. 2 is a diagram showing a state in which a monochromatic filter is moved out of an optical path in the figure.

FIG. 3 is a schematic front view showing a monochromatic filter of the present invention.

FIG. 4 is a schematic front view showing a bandpass filter of the present invention.

FIG. 5 is a schematic front view showing an aperture stop according to the present invention.

FIG. 6 is an external perspective view of an electronic blackboard device according to the present invention.

FIG. 7 is a schematic front view showing an integrated filter of the present invention.

FIG. 8 is a graph showing the object color of the writing surface and the sensitivity characteristic of the CCD.

FIG. 9 is a graph showing the amount of infrared light emitted from a fluorescent lamp immediately after startup.

[Explanation of symbols]

 Reference Signs List 1 aperture stop 1a, 8a opening 1b, 2b, 3b frame 1c, 3c, 8c screw hole 2 monochromatic filter 2a, 3a filter 3 band-pass filter 5 solenoid 5a iron core 5b wire 6 support shaft 8 integrated filter 8b Light shielding unit 10 Blackboard main body 11 Stand 12 Base frame 14 Optical reading unit 13 Window frame 13a Front window 15 Screen sheet 16 Operation panel 17 Pen tray 18 Printer 20 to 23 Roller 24 Back plate 25 Fluorescent lamp 26 Mirror 27 Lens 28 CCD S Writing surface

Claims (4)

[Claims] 1. An optical reading device for reading light emitted from a fluorescent lamp onto a writing surface of a transportable screen sheet, reading the light reflected on the writing surface onto a CCD, and reading image information on the writing surface. An electronic blackboard device, comprising: a monochromatic filter that transmits only a monochromatic wavelength of light in an optical path from the fluorescent lamp to the CCD. 2. The electronic blackboard device according to claim 1, wherein the monochromatic filter is movably installed outside the optical path. 3. An optical reader for reading light emitted from a fluorescent lamp on a writing surface of a transportable screen sheet, and entering the light reflected on the writing surface on a CCD to read image information on the writing surface. An electronic blackboard device having a unit, wherein a bandpass filter for removing a wavelength in an infrared region of the light is arranged in an optical path from the fluorescent lamp to the CCD. 4. The apparatus according to claim 1, wherein an aperture stop is provided in the optical path, and the monochromatic filter or the band-pass filter is fixed to the aperture stop. Electronic blackboard device.