阅读说明：本技术 具有增强的线锐度的电子书写器 (Electronic writer with enhanced line sharpness ) 是由 马克·莱特福特 埃里卡·蒙特贝区 佛利斯特·尼科尔森 ***·布拉甘萨 于 2018-10-19 设计创作，主要内容包括：本申请公开了具有增强的线锐度的电子书写器。一种具有增强的线锐度的液晶书写设备包括以下特征。包括前书写表面。液晶层包括胆甾型液晶和聚合物的分散体,其中胆甾型液晶的反射率响应于施加到前书写表面的压力而变化,从而在液晶层上形成图像。液晶层设置在导电层之间。导电层中的第二导电层相比于导电层中的第一导电层距离前书写表面更远离前书写表面。背衬支撑施加到前书写表面的压力。粘合剂层被设置在导电层中的第二导电层和背衬之间。图像的线锐度具有根据本公开的线锐度测量方法确定的不大于3.0的值。(A liquid crystal layer includes a dispersion of cholesteric liquid crystal and a polymer, wherein a reflectivity of the cholesteric liquid crystal varies in response to a pressure applied to the front writing surface, forming an image on the liquid crystal layer.)

1, a liquid crystal writing device with enhanced line sharpness, comprising:

a front writing surface;

a liquid crystal layer comprising a dispersion of cholesteric liquid crystal and polymer, wherein the reflectivity of the cholesteric liquid crystal changes in response to pressure applied to the front writing surface so as to form an image on the liquid crystal layer;

a conductive layer, the liquid crystal layer disposed between the conductive layers, wherein a second of the conductive layers is farther from the front writing surface than a th of the conductive layers is from the front writing surface;

a backing supporting pressure applied to the front writing surface; and

an adhesive layer disposed between the second one of the conductive layers and the backing,

wherein the line sharpness of the image has a value of no more than 3.0 as determined according to a line sharpness measurement method.

2. The liquid crystal writing apparatus of claim 1, wherein the line sharpness has a value not greater than 2.0.

3. The liquid crystal writing apparatus of claim 1, wherein the line sharpness has a value not greater than 1.1.

4. The liquid crystal writing device of claim 1, comprising electronics adapted to apply a voltage or at least voltage pulses across the conductive layer that erases the image.

5. The liquid crystal writing device of claim 1, wherein the adhesive layer is a film comprising a adhesive surface on an side thereof and a second adhesive surface on an opposite side thereof.

6. The liquid crystal writing device of claim 5, wherein the film comprises an acrylic polymer and has a thickness of at least 2 mils.

7. The liquid crystal writing device of claim 1, wherein the adhesive layer is a tape comprising a carrier film, a adhesive layer disposed on the side of the carrier film, and a second adhesive layer disposed on the opposite side of the carrier film, the second adhesive layer being closer to the writing surface than the adhesive layer.

8. The liquid crystal writing device of claim 7, wherein the carrier film has a thickness of at least mils and comprises a polyethylene terephthalate polymer, the adhesive layer has a thickness of at least mils and a peel strength, and the second adhesive layer has a thickness of at least mils and a second peel strength, the adhesive layer and the second adhesive layer comprise an acrylic polymer, and the peel strength is at least 10 times greater than the second peel strength.

9. The liquid crystal writing device of claim 1, wherein the backing comprises an aluminum-clad polymer.

10. The liquid crystal writing device of claim 1, wherein the image has an average line width of at least 1.5 mm.

11. The liquid crystal writing device of claim 1, wherein the image has an average line width of at least 2.0 mm.

12. The liquid crystal writing device of claim 1, wherein the front writing surface includes a front substrate and includes a rear substrate supporting the second one of the conductive layers.

13. The liquid crystal writing device of claim 1, comprising an opaque light absorbing layer that absorbs light passing through the liquid crystal layer.

14. The liquid crystal writing device of claim 1, comprising a translucent back layer that absorbs light passing through the liquid crystal layer.

15. The liquid crystal writing device of claim 1, wherein the front writing surface, the conductive layer, the adhesive layer, and the backing are see-through.

16, a liquid crystal writing device with enhanced line sharpness, comprising:

a front writing surface having at least 0.75ft²Surface area of (a);

a liquid crystal layer comprising a dispersion of cholesteric liquid crystal and polymer, wherein the reflectivity of the cholesteric liquid crystal changes in response to pressure applied to the front writing surface so as to form an image on the liquid crystal layer, the image having an average line width of at least 1.5 mm;

a conductive layer, the liquid crystal layer disposed between the conductive layers, wherein a second of the conductive layers is farther from the front writing surface than a th of the conductive layers is from the front writing surface;

a backing supporting pressure applied to the front writing surface; and

an adhesive layer disposed between the second one of the conductive layers and the backing,

wherein the line sharpness of the image has a value of no more than 3.0 as determined according to a line sharpness measurement method.

17. The liquid crystal writing apparatus of claim 16, wherein the line sharpness of the image has a value of no more than 1.1 determined according to a line sharpness measurement method.

18. The liquid crystal writing apparatus of claim 16, wherein the front writing surface has at least 6.0ft²The area of (a).

19. The liquid crystal writing device of claim 16, comprising an opaque light absorbing layer that absorbs light passing through the liquid crystal layer.

20. The liquid crystal writing device of claim 16, comprising a translucent back layer that absorbs light passing through the liquid crystal layer.

21. The liquid crystal writing device of claim 16, wherein the front writing surface, the conductive layer, the adhesive layer, and the backing are see-through.

22. The liquid crystal writing device of claim 16, wherein the front writing surface includes a front substrate and includes a rear substrate supporting the second one of the conductive layers.

23. The liquid crystal writing device of claim 16, comprising electronics adapted to apply a voltage or at least voltage pulses across the conductive layer that erases the image.

Generally, when a black back layer is used, the cholesteric liquid crystal initially in the focal conic state appears dark because it is weakly scattering or substantially transparent and displays a black back layer.

Fig. 2A and 2B show respectively a Boogie with a translucent back layer

This is described in U.S. patent No. 9,116,379 entitled "Electronic display with Semitransmission Back Layer," which is incorporated herein by reference in its entirety.

Many current electronic writers are configured to have a handheld size (e.g., the current Boogie of kent display corporation shown in fig. 1, 2A, and 2B

Electronic bookA writer), such a device is designed to have pressure sensitivity that can produce a suitable line of writing, like writing or drawing with a pen on sheets of paper without the need to align the palm of the hand on the electronic writer.

FIG. 3 illustrates a prior art Boogie

A side view of the electronic writer 10 and how the display subassembly 400 is supported. A bezel 402 with pressure sensitive adhesive 404 located at the periphery of the electronic writer device is adhered to the front of the display subassembly and housing 406. The display sub-assembly 400 is held in place by being sandwiched between bezel 402 and housing 406 and held in place with PSA 404.

Dry erase whiteboards are very large and can be hung on a wall for writing and drawing for many people to watch at the same time. However, these devices require the use of markers and dry erasers, which are both expensive and messy. Erasure often leaves behind a marker residue or residual image (after-image) that is difficult to remove. Further, it is difficult to preserve the image written on the dry-erase whiteboard, which is cumbersome except to photograph it.

Large format smart-board writing devices exist in, for example, classrooms, but are very expensive and have complex electronics.

The display subassembly of a large format cholesteric liquid crystal writing device will eventually sag and lift off the back surface of the device when free floating on the back surface, creating an undesirable appearance and writing experience. Liquid crystal writing devices currently on the market may use an adhesive to attach the back housing of the device to the back layer of the display sub-assembly. However, such writing devices suffer from undesirable line sharpness or line definition, which detracts from the quality and writing experience of the device.

better techniques are needed to allow consumers of various ages to easily and repeatedly write, draw, and immediately/simultaneously display to share contrastingly vivid, vibrant, multi-colored text and images for creative, educational, and therapeutic uses the present disclosure relates to electronic writers with enhanced line sharpness having other desirable features and characteristics that are detailed in the subsequent summary, detailed description, drawings, and appended claims of the present disclosure.

Summary of the disclosure

The present disclosure relates to electronic liquid crystal writing devices (electronic writers) having a pressure sensitive solid surface on which a user can write or draw with clear and crisp lines in the form of a hand-held sized electronic writer, even a large format electronic writer that can be constructed and arranged for viewing by several people at the same time.

in general, aspect of the disclosure features a liquid crystal writing device with enhanced line sharpness including the following features in the writing device a front writing surface is included a liquid crystal layer including a dispersion of cholesteric liquid crystal and a polymer, wherein a reflectivity of the cholesteric liquid crystal changes in response to pressure applied to the front writing surface forming an image on the liquid crystal layer.

In certain examples, the liquid crystal writing device includes a light absorbing layer that absorbs light passing through the liquid crystal layer, and an adhesive layer is disposed between the light absorbing layer and the backing at , the adhesive layer may be referred to as a Pressure Sensitive Adhesive (PSA). The inventors have discovered that PSAs used to attach the backing can result in an undesirable hazy or confusing appearance of the writing lines on the liquid crystal layer, which occurs in cases if the PSAs are too soft or have a rough surface topology

The electronic writer has a higher pressure sensitivity (i.e., a wider line thickness is obtained at a given applied pressure).

The electronic writer of the present disclosure may be erased using conventional erase voltage pulses and/or electronics, e.g., using BoogieThe Erase voltage pulse of the electronic writer is erased either using a suitable Erase voltage waveform and/or Erase electronics as disclosed in applicant's U.S. patent application serial No. 15/952,471, entitled "Liquid Crystal Writing Device With Slow Discharge Erase," which is incorporated herein by reference in its entirety.

Advantageously, the electronic writer of the present disclosure can be erased electronically times in total, and can be designed to allow selective erasure of images, for example, as disclosed in U.S. patent No. 8,139,039, which is incorporated herein by reference in its entirety.

The present Electronic writer may electronically capture images using, for example, techniques as disclosed in U.S. patent application publication PG pub. No. US 2010/0265214 entitled "Writing Tablet Information recording device" and U.S. patent application publication PG pub. No. US2015/0124178 entitled "Electronic Writing device with Dot Pattern recording System," both of which are incorporated by reference herein in their entirety.

Referring now to more specific features of the th aspect of the disclosure, the line sharpness has a value of not greater than 2.0, particularly not greater than 1.1.

In another specific feature, the liquid crystal writing device includes electronics adapted to apply a voltage across the conductive layer to erase an image or at least voltage pulses.

In yet another specific feature of , the adhesive layer is a film comprising a th adhesive surface on a side thereof and a second adhesive surface on an opposite side thereof.

In particular, the film may include an optically clear acrylic polymeric adhesive material that is at least 2 mils thick.

In another specific features, the adhesive layer is a tape including a carrier film, a 0 th adhesive layer disposed on a side of the carrier film , and a second adhesive layer disposed on an opposite side of the carrier film the second adhesive layer is closer to the front writing surface than the 1 th adhesive layer to the front writing surface in yet another feature, the carrier film of the tape has a thickness of at least mils and includes a polyethylene terephthalate (PET) polymer, the th adhesive layer has a thickness of at least mils and a peel strength, and the second adhesive layer has a thickness of at least mils and a second peel strength the th adhesive layer and the second adhesive layer include an acrylic polymer, the peel strength is at least 10 times greater than the second peel strength.

In other features, the backing comprises an aluminum-coated polymer. The liquid crystal layer comprises a dispersion having an effective pressure sensitivity to provide an image having an average line width of at least 1.5mm, in particular at least 2 mm.

Another features are that the liquid crystal writing device includes an opaque light absorbing layer that absorbs light passing through the liquid crystal layer.

Another features is that the liquid crystal writing device includes a translucent back layer that absorbs light passing through the liquid crystal layer.

In another feature, the front writing surface includes a front substrate and includes a rear substrate supporting the second of the conductive layers.

Yet another features are that the front writing surface, conductive layer, any substrate, adhesive layer, and backing are see-through.

The liquid crystal writing device may be designed so that all of its components sharing areas with the front writing surface are see-through this may be used with an optional additional backing layer, template or other component or object that provides suitable contrast for viewing the image of the liquid crystal layer.

The term perspective referred to herein includes only portions of the components being perspective and all of the components being perspective.

A second aspect of the present disclosure features a liquid crystal writing apparatus with enhanced line sharpness, including the following features. Including having at least 0.75ft²The liquid crystal layer includes a dispersion of cholesteric liquid crystal and a polymer, wherein a reflectivity of the cholesteric liquid crystal changes in response to pressure applied to the front writing surface to form an image on the liquid crystal layer.

Referring now to particular features of the second aspect of the disclosure, the line sharpness of the image has a value of no more than 1.1 as determined according to a line sharpness measurement method.

In yet another feature, the front writing surface has at least 6.0ft²The area of (a).

In another features, included is an opaque light absorbing layer that absorbs light passing through the liquid crystal layer.

In another features, included is a translucent back layer that absorbs light passing through the liquid crystal layer.

Another features are that the front writing surface, conductive layer, any substrate, adhesive layer, and backing are see-through.

The liquid crystal writing device may be designed so that all of its components sharing areas with the front writing surface are see-through this may be used with an optional additional backing layer, template or other component or object that provides suitable contrast for viewing the image of the liquid crystal layer.

A method for manufacturing a liquid crystal writing device of the present disclosure, comprising:

a) providing a multi-layer display sub-assembly comprising a front writing surface, a liquid crystal layer comprising a dispersion of cholesteric liquid crystal and polymer, an electrically conductive layer between which the liquid crystal layer is disposed, and an optional light absorbing layer that absorbs light passing through the liquid crystal layer;

b) providing an adhesive layer;

c) providing a backing;

d) attaching the exposed th surface of the adhesive layer to a backing to form a backing subassembly;

e) adhering the multi-layer display subassembly to the exposed second surface of the adhesive layer of the backing subassembly.

In particular, the method includes applying pressure to at least of the multi-layer display subassembly and the backing subassembly to adhere the multi-layer display subassembly to the backing subassembly.

The method of manufacturing the backing for adhering the electronic writer provides various advantages, such as preventing sagging or bulging of the display sub-assembly. The method of manufacturing an electronic writer disclosed herein also provides processing advantages such as backings reworkability and uniform adhesive layup, as well as aesthetics/yield advantages by reducing the visual effect of the particles and maintaining clear line sharpness with proper adhesive properties.

The specific features discussed above in connection with the th aspect, the second aspect, the method features and the features discussed in the detailed description are applicable in any combination to the th aspect and the second aspect above.