A partially erasable liquid crystal blackboard

Abstract

The present invention discloses a partially erasable liquid crystal blackboard, comprising: a liquid crystal display layer, including a display surface, wherein the liquid crystal display layer displays a corresponding image according to a pressure touch track received by the display surface; an identification device, used to identify the projection position and projection contour of an erasing member on the display surface, and generate a local erasing signal when the projection contour of the erasing member exceeds a preset area; an erasing circuit, used to perform image erasing on the display surface corresponding to the projection position according to the local erasing signal. The present invention realizes the erasing of a local area of ​​written content, while other areas are not affected by the erasing, overcomes the deficiency that the traditional technology can only realize full erasing, improves the user's work efficiency and use experience, and improves the commercial value of the liquid crystal blackboard and its application equipment.

Description

Technical Field

[0001] The embodiments of the present invention relate to liquid crystal technology, and in particular to a partially erasable liquid crystal blackboard. Background Art

[0002] The LCD blackboard of the prior art can only erase the entire screen, not a part. After writing a lot of content on the LCD blackboard, if you find an error in it, or after writing a formula, you find that an operation symbol in the middle is written incorrectly, you must erase all the written content and rewrite it to correct it. This causes great inconvenience to the use of the LCD blackboard and affects the writing efficiency. Summary of the invention

[0003] The invention provides a partially erasable liquid crystal blackboard to overcome the defect that the liquid crystal writing board in the prior art cannot be partially erased, resulting in low writing efficiency of the liquid crystal writing board.

[0004] An embodiment of the present invention provides a partially erasable liquid crystal blackboard, comprising:

[0005] A liquid crystal display layer, comprising a display surface, wherein the liquid crystal display layer displays a corresponding image according to a pressure touch track received by the display surface;

[0006] An identification device, used to identify the projection position and projection contour of the erasing element on the display surface, and generate a local erasing signal when the projection contour of the erasing element exceeds a preset area;

[0007] The erasing circuit is used to erase the image on the display surface corresponding to the projection position according to the local erasing signal.

[0008] Optionally, the preset area includes a first preset area and a second preset area, the erasing element includes a first erasing element and a second erasing element, the identification device is used to identify the projection position and projection outline of the first erasing element on the display surface, and a local erasing signal is generated when the projection outline of the first erasing element exceeds the first preset area, or the identification device is used to identify the projection position and projection outline of the second erasing element on the display surface, and a local erasing signal is generated when the projection outline of the second erasing element exceeds the second preset area, the first preset area is smaller than the second preset area, and the size of the first erasing element is smaller than the size of the second erasing element.

[0009] Optionally, it further includes a first erasing member placement position and a second erasing member placement position, which are used to accommodate the first erasing member and the second erasing member respectively.

[0010] Optionally, the first erasing member placement position and the second erasing member placement position respectively include magnetic members for adsorbing and fixing the first erasing member and the second erasing member.

[0011] Optionally, a first light sensor is arranged at the first erasing member placement position, for generating a first partial erasing signal when the first erasing member is removed, and the identification device sets the preset area to a first preset area according to the first partial erasing signal; a second light sensor is arranged at the second erasing member placement position, for generating a second partial erasing signal when the second erasing member is removed, and the identification device sets the preset area to a second preset area according to the second partial erasing signal.

[0012] Optionally, the erasing circuit includes a plurality of mutually spaced first electrode strips disposed on a first surface of the liquid crystal display layer, and a plurality of mutually spaced second electrode strips disposed on a second surface of the liquid crystal display layer, wherein the first surface and the second surface are two opposite surfaces of the liquid crystal display layer, and extension directions of the first electrode strips and the second electrode strips are perpendicular to each other.

[0013] Optionally, the erasing circuit includes a first driving chip connected to the first electrode strip, a second driving chip connected to the second electrode strip, and a third chip connected to the first driving chip and the second driving chip, the third chip being used to generate a local erasing driving signal after receiving the local erasing signal, the first driving chip generating a first local erasing voltage for driving the first electrode strip of the driving part according to the local erasing driving signal, and the second driving chip generating a second local erasing voltage for driving the second electrode strip of the driving part according to the local erasing driving signal.

[0014] Optionally, it further includes a local erase button, which is used to generate a first mode signal, and the erase circuit starts the local erase working mode according to the first mode signal to receive the local erase signal.

[0015] Optionally, it further includes a full-erase button, which is used to generate a second mode signal, and the first driver chip generates a third local erase voltage for driving all first electrode strips according to the second mode signal, and the second driver chip generates a fourth local erase voltage for driving all second electrode strips according to the second mode signal.

[0016] The present invention realizes erasing of a local area of ​​written content while other areas are not affected by the erasing, thus overcoming the deficiency that the traditional technology can only realize full erasing, improving the user's work efficiency and usage experience, and improving the commercial value of the liquid crystal blackboard and its application equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a partially erasable liquid crystal blackboard provided in Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic structural diagram of a partially erasable liquid crystal blackboard provided in Embodiment 1 of the present invention;

[0019] Figure 3 It is a partial circuit diagram of a partially erasable liquid crystal blackboard provided by the first embodiment of the present invention;

[0020] Figure 4 This is a partial circuit diagram of a partially erasable liquid crystal blackboard provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0022] Embodiment 1

[0023] Figure 1 This is a schematic diagram of the structure of a partially erasable liquid crystal blackboard provided in the first embodiment of the present invention. Figure 1 As shown, the liquid crystal blackboard includes:

[0024] The liquid crystal display layer 110 includes a display surface, and the liquid crystal display layer displays a corresponding image according to a pressure touch track received by the display surface;

[0025] The identification device 120 is used to identify the projection position and projection contour of the erasing element on the display surface, and generate a local erasing signal when the projection contour of the erasing element exceeds a preset area;

[0026] Specifically, the recognition device may be an infrared sensor, which is arranged around the liquid crystal display screen, and recognizes the projection position and projection outline of the erasing element on the display surface by sending infrared rays, and generates a local erasing signal when the projection outline of the erasing element exceeds a preset area. It is understandable that the recognition device is not limited to an infrared sensor. Any object that can recognize the projection position and projection outline of the erasing element on the display surface, and generates a local erasing signal when the projection outline of the erasing element exceeds a preset area, falls within the protection scope of the present invention.

[0027] The erasing circuit 130 is used to erase the image on the display surface corresponding to the projection position according to the local erasing signal. In this embodiment, when the erasing member moves on the display surface, the projection position and projection contour of the erasing member on the display surface are identified according to a preset sampling frequency, and the projection position and projection contour of the erasing member identified each time are used as the basis for image erasing, that is, the image displayed within the projection position and projection contour is erased, while the display of other areas is not affected by the erasing.

[0028] The present invention realizes erasing of a local area of ​​written content while other areas are not affected by the erasing, thus overcoming the deficiency that the traditional technology can only realize full erasing, improving the user's work efficiency and usage experience, and improving the commercial value of the liquid crystal blackboard and its application equipment.

[0029] Optionally, the preset area includes a first preset area and a second preset area, the erasing element includes a first erasing element and a second erasing element, the identification device is used to identify the projection position and projection outline of the first erasing element on the display surface, and a local erasing signal is generated when the projection outline of the first erasing element exceeds the first preset area, or the identification device is used to identify the projection position and projection outline of the second erasing element on the display surface, and a local erasing signal is generated when the projection outline of the second erasing element exceeds the second preset area, the first preset area is smaller than the second preset area, and the size of the first erasing element is smaller than the size of the second erasing element.

[0030] Specifically, the liquid crystal blackboard of the embodiment of the present invention may also include two erasing pieces of different sizes, similar to the blackboard eraser of an ordinary blackboard. When the erasing piece is erasing the liquid crystal blackboard, the recognition device will recognize the projection position and projection outline of the erasing piece on the display surface, and generate a local erasing signal when the projection outline of the erasing piece exceeds a preset area;

[0031] Optionally, the liquid crystal blackboard further includes a first erasing member placement position and a second erasing member placement position, which are used to accommodate the first erasing member and the second erasing member respectively.

[0032] Specifically, the first eraser placement position and the second eraser placement position can be around or on the side of the liquid crystal blackboard, can be set together, can also be set on both sides of the liquid crystal blackboard, etc. It can be understood that the present invention does not limit the specific position of the first eraser placement position and the second eraser placement position.

[0033] Optionally, the first erasing member placement position and the second erasing member placement position respectively include magnetic members for adsorbing and fixing the first erasing member and the second erasing member.

[0034] Specifically, regarding how to place the erasing piece, the present invention adopts a magnetic adsorption method to adsorb the first erasing piece and the second erasing piece to the first erasing piece placement position and the second erasing piece placement position respectively.

[0035] Optionally, a first light sensor is arranged at the first erasing member placement position, for generating a first partial erasing signal when the first erasing member is removed, and the identification device sets the preset area to a first preset area according to the first partial erasing signal; a second light sensor is arranged at the second erasing member placement position, for generating a second partial erasing signal when the second erasing member is removed, and the identification device sets the preset area to a second preset area according to the second partial erasing signal.

[0036] Specifically, a first light sensor is arranged at the position where the first erasing member is placed, and is used to generate a first local erasing signal when the first erasing member is removed; an identification device sets a preset area as a first preset area according to the first local erasing signal, and is used to identify a projection position and a projection contour of the erasing member on the display surface; a local erasing signal is generated when the projection contour of the erasing member exceeds the first preset area; and an erasing circuit performs image erasing on the display surface corresponding to the projection position of the first erasing member according to the local erasing signal.

[0037] A second light sensor is arranged at the position where the second erasing member is placed, and is used to generate a second partial erasing signal when the second erasing member is removed; the identification device sets the preset area to the second preset area according to the second partial erasing signal, and is used to identify the projection position and projection contour of the erasing member on the display surface, and generates a partial erasing signal when the projection contour of the erasing member exceeds the first preset area; the erasing circuit erases the image on the display surface corresponding to the projection position of the second erasing member according to the partial erasing signal.

[0038] Optionally, the erasing circuit includes a plurality of mutually spaced first electrode strips disposed on a first surface of the liquid crystal display layer, and a plurality of mutually spaced second electrode strips disposed on a second surface of the liquid crystal display layer, wherein the first surface and the second surface are two opposite surfaces of the liquid crystal display layer, and extension directions of the first electrode strips and the second electrode strips are perpendicular to each other.

[0039] Specifically, Figure 2 As shown, the erasing circuit includes a plurality of mutually spaced first electrode strips 11, a liquid crystal display layer 12, and a plurality of mutually spaced second electrode strips 13. The first electrode strips 11 are arranged on the first surface of the liquid crystal display layer 12, and the second electrode strips 12 are arranged on the second surface of the liquid crystal display layer. The first surface and the second surface are two surfaces of the liquid crystal display layer that are opposite to each other, and the extension directions of the first electrode strips and the second electrode strips are perpendicular to each other.

[0040] Optionally, the erasing circuit includes a first driving chip connected to the first electrode strip, a second driving chip connected to the second electrode strip, and a third chip connected to the first driving chip and the second driving chip, the third chip being used to generate a local erasing driving signal after receiving the local erasing signal, the first driving chip generating a first local erasing voltage for driving the first electrode strip of the driving part according to the local erasing driving signal, and the second driving chip generating a second local erasing voltage for driving the second electrode strip of the driving part according to the local erasing driving signal.

[0041] Specifically, the erasing circuit includes a first driving chip connected to the first electrode strip, a second driving chip connected to the second electrode strip, and a third chip connecting the first driving chip and the second driving chip, the third chip is used to generate a local erasing driving signal after receiving the local erasing signal, the first driving chip generates a first local erasing voltage for driving the first electrode strip of the driving part according to the local erasing driving signal, the second driving chip generates a second local erasing voltage for driving the second electrode strip of the driving part according to the local erasing driving signal, and the first local erasing voltage and the second local erasing voltage erase the image on the display surface corresponding to the projection position.

[0042] like Figure 3 , 4 As shown, chip U5 is the first driving chip, connected to the first electrode strip, i.e., the positive electrode of ITO; chip U12 is the second driving chip, connected to the second electrode strip, i.e., the negative electrode of ITO; and chip U6 is the third chip. After receiving the local erasing signal, chip U6 generates a local erasing driving signal, and sends it to the first driving chip and the second driving chip, i.e., chip U5 and chip U12, respectively. Chip U5 generates a first local erasing voltage according to the local erasing driving signal, which is used to drive part of the positive electrode of ITO after being amplified by the first triode; chip U12 generates a second local erasing voltage according to the local erasing driving signal, which is used to drive part of the negative electrode of ITO after being amplified by the second triode. The first local erasing voltage and the second local erasing voltage erase the image on the display surface corresponding to the projection position.

[0043] Optionally, the liquid crystal blackboard further includes a partial erase button, which is used to generate a first mode signal, and the erasing circuit starts the partial erase working mode according to the first mode signal to receive the partial erase signal.

[0044] Optionally, the liquid crystal blackboard further includes a full-erase button, which is used to generate a second mode signal, and the first driver chip generates a third local erase voltage for driving all first electrode strips according to the second mode signal, and the second driver chip generates a fourth local erase voltage for driving all second electrode strips according to the second mode signal.

[0045] Specifically, the liquid crystal blackboard includes a full erase button. When the full erase button is pressed, the full erase button generates a second mode signal, and the first driver chip generates a third local erase voltage for driving all first electrode strips according to the second mode signal, and the second driver chip generates a fourth local erase voltage for driving all second electrode strips according to the second mode signal. The third local erase voltage drives all first electrode strips, and the fourth local erase voltage drives all second electrode strips, so as to erase the image of the entire liquid crystal display layer.

[0046] The present invention realizes erasing of a local area of ​​written content while other areas are not affected by the erasing, thus overcoming the deficiency that the traditional technology can only realize full erasing, improving the user's work efficiency and usage experience, and improving the commercial value of the liquid crystal blackboard and its application equipment.

[0047] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A partially erasable liquid crystal blackboard, characterized in that: include: A liquid crystal display layer, comprising a display surface, wherein the liquid crystal display layer displays a corresponding image according to a pressure touch track received by the display surface; An identification device, used to identify the projection position and projection contour of the erasing element on the display surface, and generate a local erasing signal when the projection contour of the erasing element exceeds a preset area; An erasing circuit, used for erasing an image on a display surface corresponding to the projection position according to the local erasing signal; The preset area includes a first preset area and a second preset area, the erasing element includes a first erasing element and a second erasing element, the identification device is used to identify the projection position and projection contour of the first erasing element on the display surface, and generate a local erasing signal when the projection contour of the first erasing element exceeds the first preset area, or the identification device is used to identify the projection position and projection contour of the second erasing element on the display surface, and generate a local erasing signal when the projection contour of the second erasing element exceeds the second preset area, the first preset area is smaller than the second preset area, and the size of the first erasing element is smaller than the size of the second erasing element; The identification device is an infrared sensor.

2. The partially erasable liquid crystal blackboard according to claim 1, characterized in that: It further comprises a first erasing member placement position and a second erasing member placement position, which are used to accommodate the first erasing member and the second erasing member respectively.

3. The partially erasable liquid crystal blackboard according to claim 2, characterized in that: The first erasing member placement position and the second erasing member placement position respectively include magnetic members for adsorbing and fixing the first erasing member and the second erasing member.

4. The partially erasable liquid crystal blackboard according to claim 2, characterized in that: The first erasing member placement position is provided with a first light sensor for generating a first partial erasing signal when the first erasing member is removed, and the recognition device sets the preset area as the first preset area according to the first partial erasing signal; A second light sensor is arranged at the second erasing member placement position for generating a second partial erasing signal when the second erasing member is removed, and the recognition device sets the preset area as the second preset area according to the second partial erasing signal.

5. The partially erasable liquid crystal blackboard according to claim 1, characterized in that: The erasing circuit includes a plurality of mutually spaced first electrode strips arranged on a first surface of a liquid crystal display layer, and a plurality of mutually spaced second electrode strips arranged on a second surface of the liquid crystal display layer. The first surface and the second surface are two surfaces of the liquid crystal display layer that are opposite to each other, and the extension directions of the first electrode strips and the second electrode strips are perpendicular to each other.

6. The partially erasable liquid crystal blackboard according to claim 5, characterized in that: The erasing circuit includes a first driving chip connected to the first electrode strip, a second driving chip connected to the second electrode strip, and a third chip connecting the first driving chip and the second driving chip, wherein the third chip is used to generate a local erasing driving signal after receiving the local erasing signal, the first driving chip generates a first local erasing voltage for driving the first electrode strip of the driving part according to the local erasing driving signal, and the second driving chip generates a second local erasing voltage for driving the second electrode strip of the driving part according to the local erasing driving signal.

7. The partially erasable liquid crystal blackboard according to claim 6, characterized in that: It further includes a local erase button, which is used to generate a first mode signal. The erase circuit starts the local erase working mode according to the first mode signal to receive the local erase signal.

8. The partially erasable liquid crystal blackboard according to claim 6, characterized in that: It further includes a full-erase button, which is used to generate a second mode signal, the first driver chip generates a third local erase voltage for driving all first electrode strips according to the second mode signal, and the second driver chip generates a fourth local erase voltage for driving all second electrode strips according to the second mode signal.

Images