GB2423825A

GB2423825A - Viewer with sealed housing having lens at each end

Info

Publication number: GB2423825A
Application number: GB0504519A
Authority: GB
Inventors: Geoffrey Riddell
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-03-04
Filing date: 2005-03-04
Publication date: 2006-09-06
Anticipated expiration: 2025-03-04
Also published as: GB2423825B; GB0504519D0

Abstract

A viewer 1,5 comprises a housing 2,6 having a first end and a second end, wherein the first and second ends are each provided with a lens 3,8,9 (camera) to provide an internal space, and wherein the housing is sealed 10 against exchange of fluid between the internal space and an external environment in which the viewer is located, and wherein the internal space is transparent. A cable 11 for data transmission from the camera 9 is shown. The internal space may be filled with water or air or may be evacuated. The viewer may be used in poor visibility, in high or low pressure, under water or in outer space.

Description

A Viewer

Field of the Invention

This invention relates to viewers, and in particular to viewers for use in low visibility conditions.

Background of the Invention

When working in a low visibility environment, such as polluted water, a smoke filled room, or an extremely dusty environment it can be very difficult for individuals to see what they are looking for. Visibility is usually measured in terms of distance, that is visibility may be referred to as 1000 metres or 1 metre, meaning that a person of average sight can see objects 1000 metres or 1 metre away from his location. When working in conditions of extremely poor visibthty, such as diving in quarries, canals, harbours, or to great depths, the visibility may be less than the focal distance of an individual's eyes. That is the distance of separation between the object and the individual individual's eyes required to focus is greater than the distance of visibility. This presents difficulties for those who work in low visibthty conditions. For mstance, it is known that pohce divers carrying out search operations may have to swim with their diving masks touching the bottom of the canal, river, quarry, etc in which they are swimming. Not only is viewing objects difficult because the diver cannot focus, hut swimming becomes difficult and dangerous as the diver may easily swim into objects located on the bottom, without having seen them.

As well as being able to look at objects in conditions of poor visibility there are requirements to take photographs of objects located in low visibility environments. Such requirements may be recreational, commercial (e.g. in the oil, gas and water industry there may be a requirement to take photographs or video Imagery of pipe lines, valve installations, etc), or evidential (e.g. the police may need to gather photographic or video imagery of objects connected with crimes). If the visibility is * * S S S * S S S S S S S S S S S S S 555 5 5 5

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5*. S 555 SSS S less than the focal distance of the lens of the camera, it will not be possible to take pictures in which the images are sharp it would therefore be desirable to provide a viewer which separates tile individual from the an object to be viewed.

Summary of the Invention

According to the invention, there is provided a viewer as specified in Claim 1.

Brief Description of the Drawings

in the drawings, which thus trate preferred embodiments of a viewer according to the invention, and are by way of example: Figure la is a schematic representation of a viewer according to a first embodiment of the invention; Figure lb is an end elevation of the view illustrated in Figure la; Figure 2 is a cross-sectional elevation of a viewer according to a second embodiment of the invention; Figure 3a is a schematic representation of a viewer according to a third embodiment of the invention; and Figure 3b is a cross-sectional elevation of the viewer illustrated in Figure 3a.

Detailed Description of the Preferred Embodiments

Referring now to Figures la and lb there is shown a viewer 1 comprising a substantially cylindrical housing 2. In each end of the housing 2, there is mounted a lens 3. The lens may he formed from * S S S S * S S S S S S a S S S S S S *Se S S S S. S S S S S * S 1 S S S S S S S.. 5 555 555 5 plastics (e.g. Perspelor glass, or any other suitable transparent material, On opposite sides of the housing I a handle 4 is mounted. The housing 2 and handles 4 may be formed from a metal or metal alloy, which is preferably light weight. For example the housing 2 and handles 4 may be formed from aluminium. Equally, the housing 2 and handles 4 may be formed from a plastics material.

The inside of the housing is filled with a fluid which is transparent. The fluid may be a liquid such as water, or a gas such as air.

The viewer Its particularly useful for divers, in which case the inside of the housing is filled with a clear liquid such as water. The advantage of filling the housing with a liquid is that the liquid is substantially incompressible. When diving, the pressure exerted on the diver and his equipment is proportional to the depth at which the diver is at any one time, i.e. the deeper the diver dives, the greater the pressure he and his equipment are subjected to. By filling the inside of the viewer with a substantially incompressible liquid the walls and lens of the viewer are not subjected to unbalanced forces. This is because as the surrounding pressure rises so does the pressure of the liquid in the viewer, and because the liquid is incompressible the walls and lens of the viewer are not inclined to collapse.

Referring now to Figure 2, there is illustrated a viewer 5 comprising a cone shaped housing 6 having a collar 7 at one end thereof, in which a camera 9 is mounted The void 10 between the inner wall of the collar 7 and the outer surface of the camera is filled with a suitable sealant. The other end of the cone is fitted with a lens 8, which may be of Perspex, glass, or any other suitable substantially transparent material. As can be seen from the illustration, a cable 11 extends from the camera 9 so that data captured by the camera can be relayed to a display device. Rather than information being relayed via a cable the data may be transmitted by a suitable wireless system.

Where the viewer 5 is designed for under water use, the inside of the housing is filled with a substantially incompressible liquid, such as water. Where the viewer is designed for use in a gaseous S S S * S S a a * . a j. S a V S S 4.5 5 5 S. i S S S S S S 0 S I S 4 5 5 455 5 555 atmosphere, such as smoke filled environments, the inside of the housing 5 is filled with a substantially transparent gas, such as air.

Where the viewer 5 is designed for under water use, the camera 9 is a waterproof camera suitable for use by divers. Such cameras are readily available and are not in themselves part of the invention.

In the example illustrated in Figure 2, the angle 0 of the wall of the cone 6 provides a wide viewing angle which can be matched to the viewing angle of the camera 9.

Whilst the viewer 5 is illustrated with a camera 9 mounted in the collar 7, the camera 9 could be replaced with a lens, and used as a viewer by a diver.

The housing 6 may be formed from a metal or metal alloy, which is preferably hght weight, such as aluminium. In the example illustrated in Figure 2, the housing 6 is spun from aluminium. Equally, the housing 6 may be formed from a plastics material.

Referring now to Figures 3a and 3b, the viewer 10 comprises a tube 11 mounting a lens 12 at one end thereof and a camera 13 at the other. A seal 15 seals the gap between the inner wall of the tube 11 and the outer surface of the camera 13. The other end of the tube is fitted with a lens 12, which may be of plastics (e.g. Perspex), glass, or any other suitable substantially transparent material. The lens 12 is sealed in the tube 11 by a suitable sealant. As can be seen from the illustration, a cable 14 extends from the camera 13 so that data captured by the camera can be relayed to a display device.

Rather than information being relayed via a cable the data may be transmitted by a suitable wireless system.

The inside of the housing his filled with a fluid which may be in the liquid or gaseous phase, depending on the intended use of the viewer 10. Where the viewer is to be used under water, the housing 11 is filled with a substantially incompressible liquid such as water. Where the viewer is to be used in a gaseous environment, such as a smoke filled room, the viewer may be filled with a liquid a * S a a * a a a a S..

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*5'a * * a a a SS * S t * j,* a sa. *00 * such as water, or with a transparent gas, such as air. Where the construction of the viewer is suitable, the inside of the viewer may evacuated.

The viewer illustrated in Figures 3a and 3b may be a hand held device, or it may be mounted on a vehicle, such as a remotely controlled vehicle used in pipelines or drains. Such a vehicle may be an inspection vehicle delivering images to a remote location for further assessment. Equally, the images relayed by the viewer 10 may be used to facilitate operation of the vehicle from a remote location.

The viewer of the invention allows objects to be viewed clearly in conditions of poor visibility by allowing an individual's eye(s) or a camera to be located at a distance corresponding substantially to the focal length of the said eye(s) or camera. This is achieved by providing a housing filled with a substantially transparent fluid. A further aspect of the invention allows the viewer to be used in environmental conditions of high or low pressure. Where the viewer is to be used m a high pressure environment such as under water, the viewer is filled with a substantially incompressible liquid such as water. Where the viewer might be used in a low pressure environment, such as outer space, the inside of the viewer may be evacuated, or contain a gas at very low pressure.

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Claims

Claims 1. A viewer comprising a housing having a first end and a second

end, wherein the first and second ends are each provided with a lens to provide an internal space, and wherein the housing is sealed against exchange of fluid between the internal space and an external environment in which the viewer is located, and wherein the internal space is transparent.
2. A viewer according to Claim 1, wherein the said internal space is filled with a substantially transparent fluid.
3. A viewer according to Claim 1, wherein the fluid is a substantially incompressible liquid.
4. A viewer according to Claim 2, wherein the fluid is water.
5. A viewer according to Claim 1, wherein the fluid is a gas.
6. A viewer according to Claim 4, wherein the gas is air.
7. A viewer according to Claim 1, wherein the internal space is evacuated.
8. A viewer according to any preceding claim, wherein the lens at one of the first and second ends constitutes part of a camera located in the housing.
9. A viewer according to Claim 8, wherein the camera is a camera suitable for use under water.
10. A viewer according to Claim 8 or 9, wherein the camera transmits data by means of a cable or a wireless transmitter.
11. A viewer according to any preceding claim, wherein the housing is made from a hght weight metal.
12 A viewer according to Claim 11, wherein the light weight metal is aluminium.
13. A viewer according to Claim 11 or 12, wherein the housmg is spun.
14. A viewer according to any preceding claim, wherein the housing is cylindrical or conical.
15. A viewer according to any preceding claim, wherein the housing mounts at least one handle.

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16. A vicwer according to any preceding claim, wherein the pressure within the said internal space is substantially similar to the pressure of the environment where the viewer is to be used.
17 A viewer according to any preceding claim, wherein the phase of the fluid within the said internal space is the same as the phase of the fluid forming the environment in which the viewer is to be used.
18. A monitoring system comprising a viewer as claimed in any preceding claim and a monitor on which images captured by the said camera are displayed.
19. A method of viewing an object in a low visibility environment comprising the step of viewing the object through a viewer as claimed in any preceding claim.
20. A viewer substantially as shown in, or as described with reference to, the drawings.

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