A video conferencing aid for permitting face to face conversation being a holographic plate for placement
against a typical visual display. The holographic features allow a user to view the visual display whilst
providing a reflective effect such that a web cam at an offset angle is provided with a reflected view of the
user. The combined effect being to provide an improved video conferencing experience in that at least the
user appears to a remote conversant to look directly at the remote conversant.
A holographic video conferencing aid
This invention relates to a holographic surface for a visual display for internet conferencing and video
conferencing.
In the past various camera arrangements known as web cams have been proposed and provided for the
purposes of video conferencing including video, internet and web conferencing. All of these rely on a web
cam or the like to image a user and a visual display, I.e. CRT, flat panel and projector types. Video data
which may usually be compressed video data is transmitted in at least substantially two opposite routes
between a user’s terminal and a remote computer (although this may be complicated by a network where
routes are not defined strictly beyond a start and end point, and may be complicated further in the case of a
group conference where it may be considered for the purposes of this document that such data flows in at
least two opposite routes between a user’s computer terminal and a server). The intention thereof being to
provide a simulation of face-to-face interaction between two users using a flat visual display and a camera.
Unfortunately these two technologies are incompatible for this use in that to provide such a simulation the
camera must be at the location in which the user is looking, whereas to be useful the user must look at the
visual display. Geometrically therefore it is clear that the visual display or a portion of interest thereof, the
camera and the face or eye area thereof must substantially be in a straight line with either the camera
obstructing the users view of the visual display or the visual display obstructing the camera’s view of the
user.
Proposed options include a semi see-through visual display which is not only prohibitively expensive to
develop and produce but would be difficult to put into effect and would not be satisfactory as most users
additionally wish and expect to use any provided visual display for normal purposes such as office work or
multimedia viewing.
In practice users of video, net, and web conferencing position a camera close to but not obstructing their
line of sight to the visual display or portion thereof showing a remote user. This results in a poor
approximation of face to face contact as both user’s observe their respectively remote user appearing to
look away from them.
It is an object of the present invention to provide a means whereby video conferencing and the like may be
performed such that an approximation of face to face interaction may be achieved.
It is another object of the present invention to provide such a means whereby such an approximation is a
better approximation than that provided by previously known methods and means of video conferencing
and the like.
According to a first aspect of the invention there is provided a video conferencing aid comprising a sheet
having a front surface and a rear surface, at least a portion of said sheet being a holographic sheet having
optical and holographic properties such that:
a user at a substantially central front side to said holographic sheet may see predominantly through said
sheet;
an image recording means at an offset front side to the holographic sheet may record an image showing
or being enhanceable to show an image of a user at a substantially central front side to the holographic
sheet.
According to a second aspect of the invention there is provided a video conferencing aid comprising a
sheet having a front surface and a rear surface, at least a portion of said sheet being a holographic sheet
having optical and holographic properties including:
passing light from a rear side to at least a central front side such that a user substantially at a central front
side may see predominantly through said sheet; and
reflecting light from at least a central front side to at least an offset front side such that an image recording
means at an offset front side may record an image showing or being enhanceable to show an image of a
user at a substantially central front side.
According to a third aspect of the invention there is provided a hologram means, at least a portion of said
hologram means having the properties of:
being substantially planar;
having a front side and a rear side;
permitting a user at a location substantially facing the front side to predominantly see through to the rear
thereof;
permitting from at least one predetermined non-perpendicular viewing angle range at the front side a view
therefrom of said location substantially facing the front side, via a holographic reflection effect of the at
least a portion of said hologram means; and
at least limiting a view from at least one of said at least one predetermined non-perpendicular viewing
angle range at the front side of the rear side.
According to a fourth aspect of the present invention there is provided the method of recording a hologram
or manufacturing a hologram means having the properties of the hologram means of the first second or
third aspect.
According to a fifth aspect of the present invention there is provided a computer program adapted to control
a computer to provide a video conferencing function for a user, to accept image data from a camera means
and from a network, and to provide data to a visual display and to a network, wherein:
the computer program is adapted to control the computer such that the computer processes accepted
image data from the camera means so as to substantially identify any component thereof having been or
being received by the camera means from the visual display means, by comparison of at least one of an
image, a change in an image and a changing image encoded in image data provided to the visual display
means to at least one of an image, a change in an image and a changing image encoded in image data
received from said camera means; and
the computer program is adapted to control the computer such that the computer processes accepted
image data from the camera means so as to substantially remove any such component having been so
identified, to generate cleaned image data.
According to a sixth aspect there is provided at least one optical element means for negating an mirror
image reversing effect of the holographic sheet of the first, second or third aspects.
According to a seventh aspect of the invention there is provided a business method comprising of any
combination of making, procuring, disposing of, or offering to dispose of the video conferencing aid or
holographic means of any one of the first second or third aspect.
For a better understanding of the invention and to show how the same may be carried into effect, reference
will now be made, by way of example, to the accompanying drawings, in which:
Figure 1 is an illustration of a video conferencing apparatus arrangement according to an embodiment of
the invention.
In the following description, various aspects of the present invention will be described. For purposes of
explanation, specific configurations and details are set forth in order to provide a thorough understanding
of the present invention. However, it will also be apparent to one skilled in the art that the present invention
may be practised without the specific details. Furthermore, well known features may be omitted or
simplified in order not to obscure the present invention.
For the purposes of implementing any of the embodiments, further information can be obtained regarding
relevant holographic materials and techniques in the following to which reference is hereby directed:
“Topics in applied physics”, Vol, 20, Holographic Recording Materials, by H. M. Smith, Springer Verlag,
Berlin, Germany 1977;
“Optical holography” by Collier et al., Academic Press, New York, N.Y. (1971);
and also to the following patents and patent applications:
US5145756 which describes the production of a holographic mirror;
US4988152 which describes the production of a holographic mirror, particularly one which is adapted to
exhibit reflection as though from a virtual reflection surface being non-parallel to the surface of the
holographic material;
US6382798 which describes further details related to the production of holographic mirrors in this case for
particular wavelengths;
RU2068195;
JP5153492;
JP1018175;
JP8211209;
JP63199388;
Selected papers on holographic and diffractive lenses and mirrors (Spie milestone series, vol 34) by
Thomas W. Stone, Brian J. Thompson; and
Optical Holography: Principles, Techniques and Applications by P. Hariharan.
The above references are incorporated herein by reference.
The implementation of any of the embodiments described will be natural to the skilled person in the art of
holographic mirror design based on the parameters described, however reference to the above is
provided nonetheless.
According to a general embodiment of the first aspect there is provided a hologram means, at least a
portion of said hologram means having the properties of:
being substantially planar;
having a front side and a rear side;
permitting a user at a location substantially facing the front side to predominantly see through to the rear
thereof;
permitting from at least one predetermined non-perpendicular viewing angle range at the front side a view
therefrom of said location substantially facing the front side, via a holographic reflection effect of the at
least a portion of said hologram means; and
at least limiting a view from at least one of said at least one predetermined non-perpendicular viewing
angle range at the front side of the rear side.
According to a general embodiment there is provided a hologram means of the first aspect in a
substantially rectangular or trapezoid portion of an at least otherwise see through substantially rectangular
sheet.
According to a polarised embodiment the hologram means may be adapted to controllably reflect and
transmit light according to polarisation thereof.
According to another polarised embodiment the hologram means may alternatively or additionally be
adapted to controllably reflect and transmit light with predetermined polarisation thereof.
According to a rotator embodiment the hologram means may be adapted to rotate a polarisation of an
incident light and at least controllably transmit light according to polarisation thereof to control a direction of
reflection.
According to any of the embodiments there may be provided any means for attaching or removably
attaching the video conferencing aid to a visual display.
Any described video conferencing aid may be provided as part of a visual display. Alternatively any
described video conferencing aid may be provided for attachment or placement against or proximal to a
visual display.
Two main techniques may be used by a computer program to extract a user image component from a
video imaging device image data and remove a visual display image component. The first technique
includes processing such image data and comparing it to image data provided to a visual display, to
digitally identify the relationship therebetween and use such an identified relationship to extract the effect of
the visual display. A reflection from a surface or surfaces of the video conferencing aid and or of the visual
display may also be identified as a constant additional image component and thereafter removed.
A second technique which may be employed is digitally processing image data from the digital imaging
device, to identify an image component varying at a frequency corresponding to the prevalent mains power
frequency which may commonly be 50Hz or 60Hz (or may be doubles of these values due to the nature of
particularly filament light fittings varying in intensity at twice the frequency of an applied alternating current,
or even a combination of one frequency and its double in the case of mixed light fittings), and extracting
only this image component. The computer software may accept a user input indicating the prevalent mains
power frequency. Image extraction based on a frequency as low as 50Hz however is acceptable because
due to the bandwidth restrictions common even for users with broadband internet connections and a
transmitted video refresh rate (or a reciprocal of a time interval in which image data may typically be
updated in the common case where data is transmitted in a non-frame based manner) will generally be
much larger than a 50th of a second.
Additionally these or either of these techniques may be facilitated by the provision of providing
predetermined image data to the visual display having clearly defined features and requiring minimal
processing power to digitally process and identify in the image data from the imaging device.
Any described video conferencing aid may be a sheet having a hologram effect. Preferably and alternatively
any described video conferencing aid may be a sheet having a portion thereof having a hologram effect. In
the latter preferred case any join between a holographic material of the portion having a hologram effect
and the rest of the sheet substantially preferably has no reflective or refractive boundary effect, preferably is
substantially not visibly obvious from at least a central front side, and more preferably is substantially not
visible from at least a central front side. The term central front side may be taken to be the suitable and
typical range of viewing angles for a user.
According to any of the embodiments there may be provided means to reverse a recorded image about a
vertical axis. Such means may be software implemented, may be hardware implemented by
implementation of a video camera designed to transmit image data reversed, or may be implemented by
virtue of an additional mirror holographic or lens implemented to negate the effect of a first reflection.
Alternatively it is possible to construct a hologram such that it reflects an image reversed about a vertical
axis to that of normal reflections. This latter case as well as the hardware implemented case are generally
more expensive to implement and thus the software or optical element implementations are preferred. Of
course no implementation may be provided such that users see one another as though through a mirror.
This may be acceptable for social video conferencing, or conferencing over limited bandwidth, and may be
implemented where convenient.
An image presented to a user substantially at a central front side by the holographic sheet or portion may
be comprised of at least 60% of an image from the rear, and at most 40% of an image from substantially
an offset front side, more preferably at least 80% of an image from the rear and at most 20% of an image
from substantially an offset front side, more preferably at least 90% of an image from the rear and at most
10% of an image from substantially an offset front side, more preferably at least 95% of an image from the
rear and at most 5% of an image from substantially an offset front side, more preferably at least 98% of an
image from the rear and at most 2% of an image from substantially an offset front side, more preferably at
least 99% of an image from the rear and at most 1% of an image from substantially an offset front side,
more preferably at least 99.5% of an image from the rear and at most 0.5% of an image from substantially
an offset front side, more preferably substantially 100% of an image from the rear, and most preferably
100% of an image from the rear.
An image presented to a video imaging device substantially at an offset front side by the holographic sheet
or portion may be comprised of at least 2% of an image from a central front side, more preferably at least
4%, more preferably at least 10%, more preferably at least 20%, and more preferably at least 40%. As
such the rest of the image may be preferably predominantly comprised of a null or black image generated
by the holographic sheet or portion. Preferably the image presented to a video imaging device substantially
at an offset front side by the holographic sheet or portion may be comprised of at most 50% of an image
from the rear, more preferably at most 20% of an image from the rear, more preferably at most 10% of an
image from the rear, more preferably at most 5% of an image from the rear, more preferably at most 2% of
an image from the rear, most preferably substantially not comprised of an image from the rear.
An optical element provided for a video imaging device such as a webcam may preferably have a black
outer surface which may extend outwards from an imaging axis, and may preferably be matt black. Such a
provision may aid the minimisation of light from the imaging device being passed via the holographic
sheet to a user.
Preferably the holographic sheet may be provided such that a video imaging device may be placed on a
desk or work surface or otherwise below the front of the holographic sheet.
Description of the Preferred Embodiments.
An embodiment of this invention will now be explained with reference to the drawings. This invention is for
use as an audio data receptacle. Figure 1 shows an illustration of a video conferencing apparatus
arrangement including a video conferencing aid according to one embodiment of the invention.
The video conferencing aid is a sheet of material being of glass or plastic having a substantially central
portion being preferably trapezoid or rectangular and having the following holographic effect: When placed
against or close to a visual display such as a monitor or screen, a web cam placed on a user side of the
sheet and preferably below a point between a user and the sheet will be able to record substantially an
image of the user reflected holographically from the holographic portion such that a remote video
conferencing participant may perceive the user as apparently facing the remote participant during video
conferencing.
It will be expected that the image provided may not be perfect. The camera means being preferably a web
cam may need an optical adapting means connected thereto which may be a holographic
It should be noted that the reflection effect described disobeys the standard laws of non-holographic
reflection, and that the reflection effect may be analogous to that of a mirror being non-parallel to the
holographic sheet. Indeed according to some embodiments there may be an apparent non-physical mirror
aligned non-parallel to the plane of the holographic sheet.
The holographic sheet may preferably provide a user with an image of a visual display being
predominantly composed only of a component from the visual display. The holographic sheet may
preferably have a single video imaging location and be adapted to provide a video imaging device at such
a video imaging location with an image having a major image component comprising an image of a user
location at a central front direction to the holographic sheet. Such an image may additionally be composed
of an additional black or null image component. Preferably any additional image component from a visual
display location is substantially 'clouded' or otherwise heavily degraded. Preferably any additional image
component from a visual display location is substantially negligible.
The holographic sheet according to the preferred embodiment is provided with a computer readable
medium adapted to control a computer for recording device image data, receiving remote image data,
providing display image data to a visual display, and transmitting modified device image data. The
computer program provides remote image data or to a visual display or encodes remote image data within
display image data and provides modified display data to a visual display. The computer program may
control the computer to perform any combination of:
processing device image data to identify a relationship effect of display data displayed on a visual display
on device image data, and modifying the device image data to substantially remove the effect of visual
display image data provided to the visual display (this processing activity may preferably be combined with
providing predetermined image data to the visual display adapted such that identifying such a relationship
may require fewer computations than would be necessary with arbitrary image data provided to the visual
display);
processing device image data to identify a first image data component varying at a frequency or double a
frequency of local mains power, and to identify a second image data component varying at a different
frequency, and processing the device image data to remove the second component. The provision of this
processing activity is preferably provided with means to identify or accept a user input of a local mains
power frequency. The provision of this processing activity is also preferably provided with means to identify
available visual display refresh rates and where available to change a visual display refresh rate to a
frequency substantially different from frequencies equal to or double that of local mains power; and
processing device image data to identify a background image component which may vary at or at double a
local mains power frequency, but which is otherwise substantially constant, to identify a foreground image
component which may vary in intensity at or at double a local mains power frequency and which may
change and move around an image frame replacing the background image component, and to identify a
third image component which may vary in intensity at or at double a local mains power frequency but which
is not replaced by a moving foreground image but instead remains superimposed thereon at a
substantially static image location, and digitally processing the device image data to remove the third
image data component.
CLAIMS
1. A video conferencing aid comprising a sheet having a front surface and a rear surface, at least a portion
of said sheet being a holographic sheet having optical and holographic properties including:
passing light from a rear side to at least a central front side such that a user substantially at a central front
side may see predominantly through said sheet; and
reflecting light from at least a central front side to at least an offset front side such that an image recording
means at an offset front side may record an image showing or being enhanceable to show an image of a
user at a substantially central front side.
2. A video conferencing aid of claim 1 for permitting at least a video conferencing remote user during video
conferencing to observe a user being substantially at a central front side at least apparently from a viewing
angle substantially ahead of the user substantially whilst said user is facing a respective visual display.
3. A video conferencing aid of claim 1 or 2 having substantially a holographic mirror effect being a
holographically generated virtual reflective plane being non-parallel to the sheet.
4. A video conferencing aid of any one of claims 1 to 3 comprising a sheet having at least a first portion and
a second portion thereof wherein the first portion is either substantially non-holographic or has a
substantially no holographic effect of substantial benefit to video conferencing and wherein the second
portion is holographic.
5. A video conferencing aid of any one of claims 1 to 3 comprising a sheet being substantially holographic
removably or permanently affixable to a visual display.
6. At least one optical element for use with the video conferencing aid of any one of claims 1 to 5.
7. An at least one optical element of claim 6 comprising at least one optical element having a polarising
effect.
8. An at least one optical element of one of claims 6 and 7 comprising at least one optical element having
a reflective effect.
9. An at least one optical element of one of claims 6, 7 and 8 comprising at least one optical element
having a holographic effect.
10. An at least one optical element of one of claims 6, 7, 8 and 9 comprising a video imaging device.
11. An at least one optical element of one of claims 6 to 7 for placement in a optical path substantially
adjacent to a video imaging device.
12. A computer program for a computer for video conferencing using the video conferencing aid of any one
of claims 1 to 5 adapted to manipulate video data to aid apparent face to face video conferencing.
13. A computer program of claim 12 adapted to control a computer to reverse video image data about a
vertical axis.
14. A computer program of claim 12 or 13 for digitally processing visual display image data provided to a
visual display with video imaging device data obtained from a video imaging device pointed substantially at
a video conferencing aid of any one of claims 1 to 5 to determine a relationship therebeween, and for
compensating for such a relationship by modifying an image data stream from the video imaging device to
reduce or substantially remove the effect of a visual display provided with such visual display image data.
15. A computer program of any one of claims 12, 13 or 15 for digitally processing a video image stream
having a first image component varying at an ambient light variation frequency and having a second
component thereof, so as to extract the first image component for transfer in a compressed format to at
least a remote computer of a remote user.
16. At least one of a computer readable medium, computer readable signal or a combination thereof
having encoded therein the computer program of any one of claims 12 to 15.
17. A method of at least one of uploading, downloading, encoding, decoding, recording or reading the
computer program of any one of claims 12 to 15 with a computer.
18. A method of recording at least a holographic portion of a holographic sheet of a video conferencing aid
of any one of claims 1 to 5.
19. A holographic video conferencing aid substantially as herein before described with reference to figure
1.
20. A computer program for controlling a computer to process an image from a digital imaging device
pointing at a holographic conferencing aid as herein before described with reference to figure 1.
Nothing on this site constitutes legal advice, an offer, an offer to treat or a legal relationship.
Always check with your IP consultant.
