GB2479522A

GB2479522A - Use of non-solid projection screens in immersive environments

Info

Publication number: GB2479522A
Application number: GB201004921A
Authority: GB
Inventors: Barry Blundell
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-03-24
Filing date: 2010-03-24
Publication date: 2011-10-19
Also published as: GB201004921D0

Abstract

Immersive environments such as the CAVE make use of a number of physical walls which form an enclosure onto which images are projected such that any person within the enclosure experiences an immersive form of virtual reality. In this patent the enclosure is formed from ethereal walls which are able to scatter incident radiation but which are formed from particles or gaseous material and consequently provide no physical obstruction to a person wishing to pass into or out of the enclosure. In the preferred embodiment the enclosure is used to create an immersive virtual environment. In an alternative embodiment the enclosure is used to create a personal space with light being injected along the axis of the wall or walls forming the enclosure. The projected images may be in 3D as either anaglyph images or using temporal coding.

Description

IMMERSIVE ENVIRONMENTS

DESCRIPTION

Existing technologies allow images to be projected onto non-solid screens -comprising liquids (typically water) or gaseous/particle screens. In this latter respect the screens may be formed from a mist of particles able to scatter incident light. Screens formed from a sheet of water are today commonplace and companies such as FogScreen Technologies manufacture the mist' form of screen.

This patent centres upon the use of such screens to create an immersive or semi-immersive environment.

The use of sheet water formation is only practical under certain circumstances in which the flow of significant volumes of water is acceptable. On the other hand, the generation of a mist-based screen using, for example, small/extremely small water droplets (which may be generated either by passing water through very small holes, or by creating a iow temperature using, for example, liquid nitrogen) is a far more practical solution for indoor applications.

To date, such technology has focused upon creating two-dimensional screens, or screens with a smalJ curvature in the hori2ontal phine.

This patent centres upon the creation of screens which enclose one or more viewers and in the preferred embodiment, the screen is cylindrical in horizontal cross section. However, in alternative embodiments, other horizontal cross-section profiles may be used (such as rectangular, triangular, elliptical, etc).

The text that follows focuses upon the preferred embodiment of a screen which is cylindrical in cross section, which does not exclude other profiles, and the description that is included can encompass other profiles with either no change or minor changes -depending upon the nature of the application.

In the preferred embodiment, a screen which is cylindrical in hori2ontal cross-section is created using the laminar/quasi-laminar flow of small non-toxic particles -typically water-based. One or more people are situated within the interior of this ethereal screen, and a plurality of image projectors are used to project 3-D images onto the screen. These 3-D images may be encoded as anaglyph images or may use temporal coding (whereby the right and left hand views of a stereopair are depicted sequentially). In either case, the viewers within the confines of the ethereal screen don the appropriate form of viewing glasses to observe the 3-D images cast onto the screen which surrounds them.

In the case that a screen which is cylindrical in cross-section is employed, the 3-D images are to be generated using a plurality of digital light projector systems arranged external to the screen.

Typically, four or five projectors are required -the number of projectors being dependent upon their distance from the screen. As the distance is increased only four projectors need to be used and conversely as distance is reduced, five or mote projectors may be required. Observers may pass through the ethereal screen into the immersive 3-D environment at will which denotes a significant advantage to installations such as the CAVE, in which the screens take the form of hard, physical surfaces.

The projectors arranged around the immersive ethereal screen operate in a cohesive manner so as to ensure seamless presentation of 3-D data as perceived by observers within the 3-D environment.

In the case that the environment is created using a set of planar screens (giving rise to for example an immersive environment \vlMch is triangular, rectangular, pentagonal or the like, then a digital light projector is uniquely associated with each facet of the immersive environment as considered within the horizontal plane. When the environment is circular, elliptical, or when it comprises any number of curved surfaces, then one or more projectors is needed for each segment or quasi-segment of the curve. Creating the mapping between the planar image data stored within the computer, and the screen facet for each digital light projector, involves simple mathematics which will be obvious to anyone skilled in the art.

The use of ethereal materials to create an immersive environment offers practical advantages -such as the one referred to above in which observers may pass through the walls of the environment without any physical restriction. On the other hand, we appreciate that this leads to image projection which is transparent. Consequently the environment must be located within a room or the like in which there is minima' disturbance to the optical illusion presented to the observers. Typically this involves reducing external lighting and ensuring that the walls of the room or the like surrounding the environment, present minimal visual distraction, e.g. by their being painted in matt black colour.

Whilst the key objective of this patent is to provide an immersive environment which extends the capabilities of the traditional CAVE 3-D environment, there are also other practical applications. The size of the enclosure (as defined by the extent of the ethereal screen) can be sufficient on'y for one person, in which case, either 2-D/3-D images can be projected, or alternatively the ethereal screen may simply be formed from one or more colours.

Following current state-of-the-art we appreciate the ethereal screen be formed from overhead by projecting the centres which scatter projected light be injected from overhead apparatus. In the case that the screen is circular in hori2ontal cross-section, for example, then the injection apparatus would take the form of a circle through which minute droplets of water are injected vertically, or for example, that a cold material -such as liquid nitrogen -is injected vertically, the injection apparatus favouring a laminar flow.

In an alternative embodiment, a person enters the ethereal screen environment to be surrounded by a wall' of light. This wall of light to be created via the vertical projection of light using, for example, a circular ring of discrete light sources, or light generated by a single source and which through a simple optical arrangement provides vertical illumination. The light sources may cast light vertically downwards, and thereby result in light scattering with the particle forming the ethereal screen. Alternatively a circular arrangement at approximately floor level may project light in a vertically upward direction. Illumination sources may comprise a single bulb projecting coloured light, a plurality of light emitting diodes, or a plurality of laser diodes. Alternatively, the light sources may be arranged around the periphery of the ethereal environment -in a similar way to the arrangement of the digital light projectors referred to above.

Whatever the arrangement, the light sources should not necessarily comprise a single colour -the colour may change over time, to reflect for example sensing signals detected which relate to the observer's current mood.

Such an etherea' enclosure could be emçiloyed, for examp'e, in public environments when somebody is making a phone call, to provide a sense of privacy/immersion. The projected colours may encourage a positive and calm frame of mind (thereby being automatically generated) or may provide the user with feedback as to their monitored state of mind -the monitoring being based on information obtained from biometric data or from content derived from their conversation.

The current state-of-the-art enables users to "write" on ethereal screens -in which case hand movements are monitored, or the user employs a special "writing" device, and digital light projectors are used to create images on the ethereal screen which denote a user's writing action.

In the case of the personal' ethereal screen referred to above, the ethereal screen may use digital light projectors and may support writing actions by the user immersed in the environment.

Claims

CLAIMS1. The formation of an enclosed space for one or more people in which the walls of the enclosure in no way prevent a person passing through the wall/s -the walls being composed of a gaseous or particle based flow -this material being able to scatter incident radiation either elastically or inelasticaily such that any person within the enclosed space is able to visually perceive the results of the scattering process.
2. The use of small particles (dry mist) to form the wall or walls of an enclosed space, where the particles are projected from an overhead apparatus and are contained as a aminar or semi-laminar flow -these particles being defined as any particle able to scatter incident light.
3. The enclosed space being of a sufficient size to accommodate one or more people.
4. The enclosed space being circular in cross-section, elliptical, or being formed by a plurality of planar surfaces -thereby creating an enclosed space which is multi-sided in cross section.
5. The use of a plurality of image projection systems which are arranged around the enclosed space and which are able to project images onto the wall or walls that form the enclosed space. These projection systems to work harmoniously to project a unified image onto the walls of the enclosed space -such that the image is perceived as being unified by one or more people located within the enclosed space.
6. The use of projection systems able to project both two-dimensional and three-dimensional images onto the wall or walls of the enclosed space -in the case that 3-D images are projected then these may be encoded using the anag1ph technique, or temporal coding techniques, in either case those situated within the enclosed space are to wear appropriate viewing glasses via which they are able to experience the three-dimensional nature of the images projected onto the wall or walls of the enclosed space.
7. The use of a plurality of light sources able to inject light vertically into the wall or walls of the enclosed space such that the wall or walls of the enclosed space take on the colour of light injected into the walls.
8. The variation of colour injected into the walls of the enclosed space being varied so as to create an appropriate ambience within the enclosed space where the ambience is determined either under the control of the person within the enclosed space, or dynamically, any dynamic variation being modulated by background noise or music, or alternatively so as to reflect or possibly modify the mental state of the person within the enclosed space.