INFORMATION INPUT AND DISPLAY DEVICE FOR USE UNDERWATER (EMBODIMENTS)
20220163832 ยท 2022-05-26
Inventors
Cpc classification
G02F1/133311
PHYSICS
G06F2203/04102
PHYSICS
G02F1/1679
PHYSICS
G02F1/16753
PHYSICS
International classification
G02F1/16753
PHYSICS
G02F1/1679
PHYSICS
Abstract
There is provided an information input and display device for use underwater, comprising a housing, a touch screen accommodated in the housing, electronic components to provide operation of the screen, wherein the touch screen has an upper flexible layer sensitive to a mechanical stimulus sufficient to depress the flexible layer at the stimulus location, and the housing has a window for access to the upper flexible layer and is sealed with a dielectric sealant such that at least a portion of the upper flexible layer remains uncovered with the dielectric sealant to allow contact with water.
Claims
1-6. (canceled)
7. An information input and display device for use underwater, comprising a touch screen based on cholesteric liquid crystals or electronic paper and having an upper flexible layer sensitive to a mechanical stimulus, and electronic components to provide operation of the screen, wherein the screen, with the exception of at least a portion of its upper layer, and the electronic components are isolated from water by a dielectric sealant.
8. The device according to claim 7, wherein the dielectric sealant comprises a composition able to change from initial liquid or viscous flow state to rubbery or solid state after mixing its components.
9. The device according to claim 8, further comprising a housing with a cavity to accommodate the touch screen and the electronic components, wherein said housing has a window for access to the upper flexible layer of the screen and is sealed with the dielectric sealant so that at least a portion of outer surface of the upper flexible layer of the screen in the window remains uncovered with the dielectric sealant to allow contact with water.
10. The device according to claim 9, wherein the rubbery or solid dielectric sealant has a viscosity at which, in viscous flow state, the sealant is able to displace air from air cavities inside the housing.
11. The device according to claim 9, further comprising a stylus mounted on the housing to input information by applying mechanical stimulus upon the upper layer of the screen, and means for erasing information displayed on the screen.
12. The device according to claim 10, further comprising a stylus mounted on the housing to input information by applying mechanical stimulus upon the upper layer of the screen, and means for erasing information displayed on the screen.
13. The device according to claim 11, wherein said means for erasing information displayed on the screen comprises a reed switch or a hall sensor mounted in the cavity of the housing, and a magnet mounted in the stylus.
14. The device according to claim 12, wherein said means for erasing information displayed on the screen comprises a reed switch or a hall sensor mounted in the cavity of the housing, and a magnet mounted in the stylus.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Understanding that the accompanying drawings depict only typical embodiments of the invention and are, therefore, not to be considered to be limiting of the scope of protection, the invention will be described and explained with specificity and detail in reference to the accompanying drawings, in which:
[0027]
[0028]
[0029]
[0030]
[0031]
DETAILED DESCRIPTION OF THE INVENTION
[0032]
[0033] As will be an apparent to those skilled in the art, the device according to the invention can be, in principle, used without a housing 1. The housing is a preferable, but not essential element of the device, intended only for protection against external impacts, for aesthetic purposes, and for comfort of use. The main prerequisite for operability of the device is sealing the screen and other elements of the device from penetration of air and water, rather than provision of a housing, as will be shown below.
[0034] In this embodiment, a screen 2 is mounted in a housing 1.
[0035] As stated before, the main problem with prior art devices is the inability of underwater use of touch screens with the upper layer (writing surface) in direct contact with water.
[0036] Numerous attempts have been made to find suitable devices with touch screens, which would remain functional at direct water contact with the upper layer (writing surface) of the screen.
[0037] It was quite unexpectedly discovered that touch screens, e.g. based on cholesteric liquid crystals, can remain functional when used underwater at a depth of at least 40 meters, although they have never been earlier used underwater in direct contact with water.
[0038] The prerequisite for using such devices under water is the provision of their complete water and air tightness for protecting internal elements of the device from effects of ambient pressure and water.
[0039] Air can get into the interior of the device e.g. in the process of its assembly.
[0040] If air or water gets inside the device, it will be substantially impossible to enter information by acting upon the screen, e.g. by a stylus, under water due to the presence of air-filled cavities and/or water penetration, including the space between the screen boards. In addition to leaks leading to closure of electrical contacts in the device and failure of the screen, air pressure in the cavities increases with depth and causes, inter alia, deformation of the screen and often the housing as well.
[0041] It was found advantageous to use underwater devices with cholesteric liquid crystal screens. Unique properties of cholesteric screens permit using them underwater with the upper layer (writing surface) in direct contact with water.
[0042] An advantage of using such screens is that cholesteric screens spend energy only on changing the image, while a static image can displayed for a long time even when power is turned off. In addition to the extremely low power consumption, advantages of cholesteric liquid crystals include the ability to change their state under external electric field. In addition, liquid crystal screens showed good performance when immersed in liquid medium.
[0043] Drawing devices based on cholesteric liquid crystals are known in principle, e.g. https://myboogieboard.com/products/. These devices allow input of information by acting upon the screen with a stylus or another hard object, including a fingernail. However, no attempts have been made before to use such devices under water, especially with the screen in direct contact with water.
[0044] The device comprises a housing, an LCD screen and electronic components, including an electronic printed circuit board and a battery electrically connected to the screen, and a stylus. The device is operated by the unique property of cholesteric liquid crystals, which flow at different speeds depending on the direction of pressure (anisotropic flow). When a thin film with cholesteric liquid crystals is placed between two special plastic sheets, the anisotropic flow forces molecules to self arrange so that to reflect light at the locations where the stylus touches the plastic sheet and depresses it. Liquid crystals are surrounded by polymer columns that control the flow, thereby providing superior sharpness of lines. Recorded image is retained until it is erased by pressing a button (or by effect of a magnet upon a hall sensor or reed switch, which can be used instead of the button), which activates generation of electric field (electric pulse). At electronic erasure, a burst of electric field rearranges molecules so that they become less reflective.
[0045] In terms of quality, cholesteric liquid crystal screens are closer to e-paper screens, therefore, any type of said screens can be used underwater.
[0046] Conventional electronic paper device Sony DPT-RP1 (https://www.sony.com/electronics/digital-paper-systems/t/digital-paper-notepad), which permits input of information by acting upon a touch screen with a stylus, has also proven to be applicable in the present invention. In contrast to traditional liquid crystal screens using a matrix gap to generate an image, e-paper generates an image in reflected light like an ordinary paper and can store images of text and graphics for a quite long time without consuming electrical power and spending it only on changing the image.
[0047] Therefore, it has been found that any device comprising a touch screen with an upper flexible layer sensitive to a mechanical stimulus can be used underwater for input and display of information, particularly, devices with cholesteric liquid crystal touch screens, e-paper devices, and other devices with similar principles of operation. As will be apparent to those skilled in the art, other similar devices can also be successfully used without departing from the idea, principle and scope of the present invention. When choosing the appropriate device, the primary idea is to observe the principle that the screen, which is directly in contact with water, must have a layer sensitive to a mechanical stimulus, and this layer must have flexible properties.
[0048]
[0049]
[0050] The housing 1 can have a design at which the screen tightly adheres, over its edges, against the upper (front) portion of the housing from the inside and is fixed, for example, by an adhesive bond or ultrasonic welding or double-sided moisture-resistant tape.
[0051] On the side of terminals, the screen is sealed simultaneously with sealing the electronic printed circuit board with electronic components thereon.
[0052]
[0053] Dielectric sealant 10 must have the ability to exclude its movement once it has solidified and to eliminate direct effect of ambient pressure variation with depth on electronic components of the device and internal elements of the screen.
[0054] It is desirable that the dielectric sealant was able to change, in a while after mixing its components, from initial viscous-flow state to final rubbery or solid state. This is because during the change from viscous flow state to rubbery or solid one, the dielectric sealant expels air from free cavities of the device, and fills free cavities in the closed housing between the device components. Concurrently, the device screen retains its functionality underwater when exposed to ambient pressure and force as the external ambient pressure applied to the device and its elements changes with depth. This effect is provided, inter alia, by the absence of free air cavities in the device housing, including directly under the screen, which is arranged on and adhered to (as seen in
[0055] Unlike gel used in patent publication US 2005/0110765 to expel air from air pockets, the dielectric sealant solidifies after being placed in the device housing and does not leak out, reliably holding in place and protecting all internal components. Furthermore, unlike gel, the proposed dielectric sealant is rubbery or solid in working condition, which is very important for using under the exposure to ambient pressure as the depth is increasing, since in the solidified state it can reduce vibration, shock and other negative effects on the device. In addition, the gel, when flowing, can flow under the screen or between the screen boards, which is not the case of the rubbery or solid dielectric sealant. If gel is filled insufficiently, it will flow (squeeze out) from one end of the housing to the other. With rubbery or solid dielectric sealant, this is not possible. Therefore, gel used in patent publication US 2005/0110765 is substantially inapplicable for use in the inventive structure.
[0056] For example, as the rubbery dielectric sealant 10 having the ability to change from viscous flow state to rubbery one, a heat-conductive potting silicone dielectric sealant can be used, which is capable of sealing both in open and in closed volume. In Russia, such sealants are produced, for example, under SUREL-SL-KST trademark (http://www.surel.ru/silicone/70/), the heat-conductive potting silicone dielectric sealant comprising a two-component system able to change from viscous flow state to elastic state after mixing components A and B, where component A is a filled organosilicon polymer, and component B is a cold curing catalyst.
[0057] In addition to the above properties, the used elastic dielectric substance exhibits: [0058] moderate damping and shock-absorbing properties; [0059] sufficient elasticity; [0060] high dielectric properties; [0061] resistance to high and low temperatures.
[0062] As will be apparent to those skilled in the art, other similar materials with similar properties can be used as the dielectric sealant. For example, Silagerm 2206 (1/1) compound, Silagerm 2206 compound, Viksint PK-68, Viksint K-68, KPTD-1, Dow Corning Sylgard 184, Dow Corning Sylgard 182 compound can be used. It is also possible to use epoxy and other potting compounds going finally into solid state, e.g. Etal-1472, Etal-1471 and other similar compounds.
[0063] Electronic printed circuit board 7 with electronic components, battery terminals, screen terminals, and screen edges on the ends along the perimeter must be immersed into the dielectric sealant 10 and thus isolated from environmental influences and force effects when the ambient pressure on the device changes with depth, and from shock and vibration. Dielectric sealant 10 is poured into the housing 1 so that it does not get directly under the screen, but fills the space inside the housing along the perimeter and seals the screen along the edges. In addition, as already mentioned above, the screen per se adheres tightly to the rigid substrate 5 or directly to the back wall 6 of the housing 1.
[0064] Mating edges 9 are arranged over the perimeter of the housing 1.
[0065] Whether the device comprises a housing or not, the prerequisite for its operability is that the interior of the screen and electronic components are sufficiently isolated from penetration of air and water, and thereby isolated from environmental influences and force effects as the ambient pressure upon the device changes with depth.
[0066]
[0067] Upon mounting the screen 2 on the front cover 13 of the housing 1 of the information input and display device and placing all the principal internal elements, including the electronic printed circuit board 7 and the battery 8, a dielectric sealant is poured over the entire plane of the open housing 1 with the mounted screen 2 to fill free air cavities. Then, the back cover 11 of the housing 1 is closed and secured by ultrasonic welding or adhesive bonding along the entire perimeter. As the result, the back cover 11 of the housing 1 provides tight contact with the rear portion of the screen 2 so that there is no air gap between the back cover 11 of the housing 1 and the screen 2. The rear portion of the screen 2 can also be pressed by a rigid substrate 5 (see
[0068] To replace the battery 8 in the housing 1, a special compartment (not shown) is provided with a cover 12 containing at least one o-ring, which is opened to replace the battery 8, and then the back cover 11 of the housing 1 is tightly closed.
[0069] The battery can be substituted, for example, for a rechargeable battery. In this case, the device is further provided with a sealed charging port or a wireless charging module.
[0070] The device can further comprise a module for storing the entered and displayed information and a module for transmitting information to other devices.
[0071]
[0072] The information input and display device was tested in operation underwater at a depth of 40 meters at the water temperature of +28 degrees. Under these test conditions, the device was fully functional throughout the entire test cycle consisting of ten dives, each for 45-60 minutes.
[0073] The inventive information input and display device for use underwater is light in weight, easy to manufacture and convenient for making notes, records and drawings underwater, and consume low power.