GB2429141A

GB2429141A - An ambient light shield

Info

Publication number: GB2429141A
Application number: GB0516196A
Authority: GB
Inventors: John Collins
Original assignee: SIMULATION CONSULTANTS Ltd
Current assignee: SIMULATION CONSULTANTS Ltd
Priority date: 2005-08-06
Filing date: 2005-08-06
Publication date: 2007-02-14
Anticipated expiration: 2025-08-06
Also published as: GB0516196D0; GB2429141B

Abstract

Generally a liquid crystal (LC) type display is difficult to view in bright conditions, particularly in sunlight. The light shield 10 for a portable electronic device 50 incorporating an LC display comprises a hood having first and second lateral or side portions 12, 14. The lateral portions are connected to upper and lower panels 18, 20 so that in use the shield 10 encloses a volume having first and second apertures, through which a viewer may view the display 60. A rear panel (16, fig 4) lies behind the display 60 to hold the shield in place. Ideally the shield (10) is formed from a single sheet of flat foldable material such as card or synthetic plastics and may be folded flat for storage or otherwise. An optional cover for a keyboard is provided. The light shield 10 is intended for use with an electronic device having a display or screen such as a portable personal computer or laptop.

Description

A LIGHT SHIELD

Background

This invention relates to a light shield, more particularly, but not exclusively to a light shield for an electronic device and more specifically a portable electronic device having a screen or display.

A number of portable electronic devices have been developed and become quite common over the last 10 to 15 years. These include: portable personal computers (laptops), electronic notebooks, palm held devices, mobile communicators and pagers. A common feature with all the aforementioned portable electronic devices is that they have a screen for display and keypads or keyboards. Generally the screen or display for these devices is a liquid crystal (LC) type display. Liquid crystal displays are flat and therefore more compact than other types of displays.

The invention is also suitable for use with non-LCD displays, such as for example, electro-luminescent plastics and light emitting polymers (LEP) which may in the future offer an alternative to LCD displays.

Prior Art

There are two basic types of liquid crystal display: a reflective liquid crystal display (LCD) and a transmissive liquid crystal display (LCD). Liquid crystal displays of the transmissive type require a backlight. The backlight is required in order to provide sufficient illumination so that a viewer can see the different intensities and colours of light transmitted through the liquid crystal material.

The other type of liquid crystal display is a reflective LCD. This type of display is common in smaller devices such as pocket calculators and pagers where space is at a premium. Reflective LCDs are also used where power consumption is crucial as they rely upon a user viewing the display with ambient light.

Generally the lighting energy of a backlight, which illuminates transmissive liquid crystal displays, is relatively modest when compared with ambient lighting conditions. One reason for this is that the energy required in order to light the display is usually supplied by a battery. A result of this has been that in bright conditions, particularly in sunlight, the overall lighting levels have made it difficult to view the liquid crystal screen.

Additionally, where ambient lighting conditions are particularly bright, a viewer has further difficulties viewing the screen because of reflection of ambient images from the screen.

The present invention arose in order overcome the aforementioned problems.

Summary of the Invention

According to the first aspect of the present invention there is provided a light shield for a portable electronic device comprising: a hood having first and second lateral portions, said lateral portions being connected, in use, to a panel, so as to enclose a volume, which volume has first and second apertures, said first aperture having substantially the same area as the display and said second aperture defining an opening with a smaller area than the display, whereby, in use, a user views the display through said apertures.

As the plane defining the panel, to which the lateral portions are connected, is at an angle with respect to the plane that defines the hood, when the light shield is used with a laptop computer or a device with a keyboard, it will be appreciated that the hood encloses the screen but allows clear access to, and visibility of, the keyboard.

Ideally the hood is a continuous surface or cover, and may comprise a flexible material such as a rubber or synthetic plastics boot or cover.

Alternatively the hood comprises a plurality of flat sheets, arranged to define a volume that in use encloses the screen and defines a volume, which is substantially enclosed from external ambient light.

In use therefore a viewer views the display in a condition of ambient light that is considerably less within the volume than the ambient light level outside the volume. A principle advantage of this is that a user's eye adapts better to the light levels defined within the volume (and is therefore capable of focusing onto a display whose contrast is considerably greater with respect to the ambient light conditions within the volume), than it does in normal ambient viewing conditions.

Preferably the light shield and any lateral sheets or surfaces are formed from a material that is light in weight. The material may be a synthetic plastics material or it may be a stiffened card or paper based product.

In an alternative embodiment the lateral sheets or surfaces may be formed from a flexible material opaque material.

In a further alternative embodiment the light shield may be formed from a flexible material and have flexible lateral members or relatively rigid flexing members inserted through suitable stiffening sections, in a similar fashion to a sail that receives batons.

Ideally the light shield, when assembled, defines a generally parallelepiped form such as a square based frustum, in order to correspond to the generally square or rectangular shape of a computer display. However, it will be appreciated that circular displays could have a circular type screen and likewise any other shaped display, such as oval or triangular, or indeed any other shape may have a suitable shaped light shield in order to prevent ambient light from impinging directly onto the screen.

Advantageously the second aperture or opening is of substantially the same width as the screen. However, the height of the aperture or opening is ideally substantially less than the height of the screen. The reason why the height of the opening is less is due to the fact that the aspect ratio of the opening does not have to be the same as the aspect ratio of the screen. An advantage of this is that the shorter second aperture reduces the amount of ambient light, which is incident of the screen. Furthermore because a viewer is usually some distance from the screen it will be appreciated that, due to the second aperture or opening being a distance from the screen, a viewer can view the complete screen through the relatively shorter second aperture, provided the aperture is placed some distance from the screen.

The light shield is ideally dimensioned and arranged in order to fit over a display as a single item. It may therefore be supplied or sold in a preassembled form. However preferably the light shield can be removed from the display and folded or flat-packed in order that it may be carried in a carrying case.

Seams along edges between faces or panels are ideally opaque. Opacity of the seams is ideally ensured by light impervious layers, flaps or seams.

In a particularly preferred embodiment a demountable material is disposed at regions or along edges of the panels or faces so as to enable them to be connected and disconnected one from another. An example of such a demountable material includes demountable devices such as poppers, buttons, clips, an adhesive material or a VELCRO (registered trademark) material.

Ideally where VELCRO material is used a continuous strip of VELCRO is provided on one surface and a series of connecting pips, studs or smaller areas of VELCRO connecting material or layers are provided on the other surface.

Where interconnecting strips are used an overhang is ideally provided on one surface so that it can be folded over an edge, thereby preventing any stray or ambient light from entering into the relatively darkened volume defined by the light shield.

Embodiments of the invention will now be described, by way of exemplary example only, and with reference to the Figures in which:

Brief Description of the Figures

Figure 1 is an overall diagrammatical view of a light shield mounted on a personal computer in use and shows the relationship of a user's eye to the light shield and screen of a personal computer; Figure 2 is an overall view of a light shield mounted on a personal computer or laptop; Figure 3 is an overall view of the light shield prior to it being unfolded and assembled; Figure 4 is a plan view of an unfolded light shield ready to be assembled; Figure 5 is an overall view of the part folded light shield ready for covering a personal computer; and Figure 6 is an overall view, from one side, showing the light shield mounted on the personal computer laptop.

Detailed Description of Preferred Embodiments of the Invention Referring to the Figures generally, in which like parts bear the same reference numerals, there is shown a light shield 10 which is placed around a personal computer or laptop 50 which has a screen 52.

The light shield 10 comprises: first and second lateral or side panels 12 and 14, a back panel 16, a top panel 18 and an under panel 20. All the panels 16, 18 and 20 are substantially rectangular.

In use, the panels 12, 14, 16, 18 and 20 are connected or attached one to another along their edges, so that, first and second lateral or side panels 12 and 14, top panel 18 and under panel 20 define a square based frustum.

Under panel 20 lies in a plane which is at an angle of between 20 and 60 to the plane of the screen 50. Back panel 16 is spaced from the square based frustum, so that a slot 70 is defined. When assembled, slot 70 has the same width as the thickness of the screen 52. The light shield 10, thus when fitted to a laptop 50 surrounds the screen 52, thereby preventing substantially any light from entering the shielded volume. Once assembled the light shield defines a first aperture 60 (which is of substantially the same area as the screen 52); and a second aperture 80 through which the user may view the screen 52.

Panels 12, 14, 16, 18 and 20 are defined by flat stiffened surfaces, defining panels of a rigid substrate or material. Each of the panels is connected to another by seams or edges 90. The substrate or material ideally has strips of material such as VELCRO (Registered Trade Mark) 40 disposed along preferential edges of panels 12, 14, 16, 18 and 20.

In an alternative embodiment small patches or pads of VELCRO material are disposed and are so located as to engage similar pads on edges when folded.

The engagement of the pads ensures both mechanical rigidity or strength is imparted to the light shield as well as ensuring that edges and seams are light impervious.

In a yet further alternative embodiment edges or flaps are incorporated so that light is prevented from entering the volume defined by the light shield. These may be formed from an elastic or flexible material so as to permit the light shield to be placed over and around a personal computer, laptop, pocket calculator or other portable electronic device. In the embodiment depicted in Figure 4 edges 90 are formed with the lateral panels 12 and 14, and with under panel 20, so as to fold back and provide a light impervious edge.

Lateral or side panels 12 and 14 may be folded back onto a top panel 18.

Lower 20 and back 16 panels may be arranged to fold back on one another in a fashion to permit a user to fold the light shield so that it can be flat packed.

An advantage of this is that a folded light shield occupies a relatively smaller volume than the assembled light shield. This enables the folded light shield to be packaged and dispatched in an envelope to a user.

Further folds may be formed within the light shield, depending upon the type of screen for which it is intended, so as to enable a flat packed light shield to be dispatched, for example by post, in a regular A3 or A4 envelope.

In an alternative embodiment of the invention, a dull or blackened matt surface may be deposited or formed on inner surfaces of the panels of the light shield so as to reduce reflection of light within the volume defined by the panels 12, 14, 16, 18 and 20 when assembled, thereby improving the effectiveness of the light shield.

Referring now to Figure 1, which shows the relationship between a viewers eyes; the distance between a viewer's eyes and the first and second apertures defined by the light shield; and the distance between a viewer's eyes ad the screen.

Ideally the height of the second aperture of the light shield defined by the height 0 is as short as possible. As a general rule, the smaller the dimension D, the less light is able likely to enter and impinge upon the screen or display 52. However, the requirement is that a user will naturally wish to sit a sensible distance, typically 30cm to 150cm away from a screen 52. Therefore the height D (aperture 80) cannot be too small otherwise a viewer will be unable to view the entire screen 52 through such a small aperture.

A compromise is thus reached between the height D being of a sensible height so as not to permit too much light to enter the volume, whilst still being of a suitable dimension as to enable a viewer, when sat at a reasonable distance from the screen 52, to view the screen 52 comfortably or at least to view a substantial portion of the screen. Typically the dimension D is between 5cm and 20cm, ideally it is between 5cm and 15cm and most preferably it is between 5cm and 10cm.

Additional pre-folded strips (not shown) may be provided, either by folding or folds formed in the top panel or lower panel or by an additional strip which may be attached to the top or lower panel so as to enable variation of this height at D. These pre-folded strips enable the light shield to be used by users of differing short or long sightedness or at different image size, with the flexibility, of permitting such viewers the choice of widening or narrowing the depth of the aperture. The pre-folded strips may also be used as a light visor in particularly bright conditions.

Variation may be made to the above mentioned embodiments by providing, for example, a flexible material which is continuous between flaps or panels so that, for example, the light shield may be placed around smaller hand held palm devices or mobile telephones so as to light shield them from bright sun or ambient light.

It will be appreciated that further variations to the embodiments described may be made without departing from the scope of the invention. For example, although the above mentioned embodiments have been described generally with reference to an embodiment whose side panels are substantially parallel, it will be understood that thee panels may taper slightly so that the width of the first aperture may be slightly less than the second aperture.

There is likewise an embodiment within the scope of the invention that has a flexible, transparent layer that is adapted to cover a keyboard. The cover may be integrally formed with the light shield or demountably connectable thereto.

An advantage of this embodiment is that the light shield, with integral keyboard cover enables the laptop or portable electronic device to be used in particularly hostile environments, for example where there is sand, dust and/or rain. Similarly a transparent sheet or cover may be placed across the first aperture, thereby defining a continuous surface that completely surrounds the laptop or portable electronic device, so that, in use, a continuous surface is defined. Ideally the continuous surface hermetically seals the laptop or portable electronic device from the environment, whilst permitting a user to use the keyboard and view the screen.

Where a flexible, transparent layer is provided to cover the keyboard, the cover ideally has an anti-glare surface provided thereon.

It will be appreciated that further variations to the embodiments described may be made without departing from the scope of the invention.

It will also be appreciated that the light shield in its most preferred embodiment comprises a single sheet of opaque or substantially opaque material, adapted to be folded along lines of weakness, or along prefolded lines, so as to define a cover for use with a display or screen, which cover, in use, reduces the amount of ambient light that impinges the screen.

Claims

Claims 1. A light shield for a portable electronic device, having a

display or screen, comprises: a hood having first and second lateral portions, said lateral portions being connected, in use, to panels, so as to enclose a volume, which volume has first and second apertures, said first aperture having substantially the same area as the display and said second aperture defining an opening with a smaller area than the display, whereby, in use, a user views the display through said apertures.
2. A light shield according to claim I wherein the shield comprises a plurality of flat sheets, which in use are arranged to enclose the display or screen thereby defining a volume, which is substantially enclosed from external ambient light.
3. A light shield according to claim I or 2 wherein the shield comprises a single sheet of material with a continuous surface having slots and lines of weakness formed therein.
4. A light shield comprises a single sheet of opaque, or substantially opaque, material adapted to be folded along lines of weakness, or along pre-folded lines, so as to define a cover for use with a display or screen, which cover, in use, reduces the amount of ambient light that impinges the screen.
5. A light shield according to claim 3 or 4 wherein the material is flexible.
6. A light shield according to claim 5 wherein the flexible material has relatively rigid members inserted through stiffening sections.
7. A light shield according to either claim 5 or 6 wherein the material comprises rubber or synthetic plastics. \0
8. A light shield according to any of claims I to 6 wherein the material is stiffened paper or card.
9. A light shield according to any preceding claim wherein sheets of material are formed from a material that is light in weight.
10. A light shield according to any preceding claim which when assembled defines a generally parallelepiped form.
ll.A light shield according to any preceding claim that is supplied or sold in a pre-assembled form.
12.A light shield according to claim 11 is adapted to be folded or flatpacked.
13.A light shield according to any preceding claim has seams along edges between sheets or panels are opaque.
14.A light shield according to claim any of claims I to 3, any claim depending on claims I to 3, wherein the light shield comprises a demountable means disposed at regions or along edges of the panels or sheets so as to enable them to be demountably connected one from another.
15.A light shield according to claim 14 wherein the demountable means includes: poppers, buttons, clips, an adhesive material or a hook and loop material.
16.A light shield according to any preceding claim wherein an overhang is provided on one surface so that it can be folded over an edge, thereby preventing any stray or ambient light from entering into the interior volume.
17.A light shield according to any preceding claim has a flexible, transparent layer that is adapted to cover a keyboard of the device.
18.A light shield according to claim 17 wherein the cover is integrally formed with the shield.
19.A light shield according to any of claims 17 or 18 wherein the cover has an anti-glare surface provided thereon.
20.A light shield substantially as herein defined and as illustrated in the Figures.