Description
This application is divided out of Indian Patent Application No. 3085/KOLNP/2006 dated
25th October 2006, which in turn is the national phase entry of International (PCT)
Application No. PCT/IB2005/001216 having an International Filing Date of 4th May 2005.
Field of the Invention
The field of the invention is the presentation of motion picture films, and in particular
in the cost-effective conversion of a standard, existing multiplex theatre space into one
allowing a qualitatively different motion picture presentation experience.
Background
Motion picture exhibition has seen a number of changes since its inception in the late
19th century. Generally, the main variables in motion picture exhibition have been the
dimensions of the theatre enclosure and correspondingly the number of seats therein, the size
of the screen upon which images were projected and the dimensions or format of the. film
negative which contained the images for presentation. Although a number of film formats
were considered, one format, 35mm wide film having an image aspect ratio of 4:3 became
the industry standard. Motion picture theatres gradually evolved in size from smaller theatres
to larger so-called palace theatres featuring several hundred to thousands of seats, balconies,
and elaborate facades. Despite the impressive and somewhat regal atmosphere these theatres
continued to feature 35mm film projected onto narrow width screen. Eventually in the late
1920s, motion picture producers and exhibitors started experimenting with larger film
formats which could enhance the visual immersion of theatre patrons and live up to the size
and scope of the large palace theatres.
Some of the wide gauge/wide screen processes that appeared to challenge the 35mm
film standard included Magnascope, Polyvision, Hypergonar and Fox Grandeur.
Magnascope used a novel magnifying lens to enlarge a standard 35mm frame. Polyvision
used multiple 35mm film projectors to stitch together a composite image, while Fox
Grandeur replaced 3 5mm film entirely with a new 70ram wide film format
Finally Hypergonar used a novel method of anamorphically squeezing images onto a
35mm frame during filming and then reversing the process upon projection to fill a larger
projection screen.
Although technically and aesthetically successful, the proposed wide screen systems
failed to replace 35mm as a film standard in the economically depressed 1930s and were soon
abandoned. Conditions had changed somewhat by the early 1950s and the motion picture
industry saw a resurgence of proposals for wide gauge/wide screen systems. Foremost
among the new systems were Cinerama, a multiple 3 5mm projection system, Cinemascope,
an anamorphic system, Vistavision a 35mm 8 perforation format system and Todd AO, a
wide gauge system using a 70mm 5 perforation 30 frame per second format The new
formats were successful at the box office and survived for a number of years, but none was
able to seriously challenge the 35mm film standard.
A third wave of wide gauge/wide screen motion picture exhibition started in 1969, led
by MAX Corporation, which featured the use of horizontally travelling 70mm film with a
film frame of 15 perforations in width resulting in an image area about ten times that of
standard 35mm. In addition to the large film format MAX® re-conceptualized the theatre
viewing space by providing significantly larger screens which extended beyond spectators
fields of view, steeply raked seating area to give unobstructed viewing of said large screen,
and high fidelity six channel sound to surround the audience. The net result of these
advances was a theatre experience in which audience members were immersed in image and
sound as never before. MAX® theatres were successful in the institutional and exhibit
marketplace. Other competing large format systems include Showscan's 70mm 5 perforation
film projected at 60 frames per second (versus the standard 24 fps) and Iweric's 70mm 5, 8
and 15 perforation film systems.
In most cases MAX® systems were installed in custom designed motion picture
theatres having a large volume to house both the large screen and a steeply raked seating
deck. Occasionally MAX® projection systems were placed in large hall converted stage
theatres. MAX® screens could be placed in front of the stages in such theatrical structures
without building structure modifications because of the large existing clear height. In some
cases, such as at the Museum of Natural History in New York City, a retractable MAX®
screen was placed in front of the stage that had an existing 3 5mm screen at the back of the
stage. Some seats at the side of the theatre near the position of the MAX® screen were
removed because the visual quality at those locations was poor. The slope of the seating
areas in these theatrical theatres is typically shallow, and financial constraints prevented
conversion to a more desirable steeper slope. As a result, the viewing conditions in such
converted theatres were not optimized for viewing MAX® motion pictures.
Grand theatres of the type frequented in the 1920s thru 1950s were sometimes
converted to house the emerging wide gauge/widescreen systems of the 1950s. Conversion
consisted of changing the width and curvature of the screen to match the new wider picture
aspect ratio and removing a relatively high percentage of seats that no longer had viable
viewing conditions. Screen centres were basically positioned at the original screen centre
position at the rear wall of the theatre, and the rake of seats in the theatres was not a
consideration in the conversion process.
Another type of theatre conversion addresses the desire to present motion pictures in
either of two common aspect ratio formats, which are 1:85 : 1 and 2.35 : 1 The conversion
process involves adjusting the curtain masking around the screen to suit the format of
presentation as well as changing the lens and aperture plate. The position of the screen itself
does not change.
A major trend in the motion picture industry starting in the 1970s was to group a
number of small 3 5mm film theatres into one large complex, or so-called multiplex theatre.
These theatres, although profitable, did not provide patrons with a quality viewing
experience. Over time movie attendance declined partly because of new home entertainment
technologies such as cable TV, video cassette recorders, and home movie rentals. In the
1990s the motion picture exhibition industry responded to declining movie attendance by
building new theatres offering stadium seating - placing each row of seats on its own tier - to
improve the sight lines and thus the viewing experience of patrons. This industry advance
has been very successful in improving movie attendance and is now an expected feature for
theatre patrons; conventional low slope seating decks are seen as "old" and inferior. (LA
Business Journal). The new stadium seat theatres, while an improvement over traditional
multiplex theatres, still rely on standard 35mm film projectors and do not provide patrons
with a wide field of view or highly immersive experience.
It should be noted that in the later half of the 1990s the use of digital projectors began
in a few multiplex cinemas. This trend in time will increase as digital projection systems get
better in quality and higher in image resolution.
Another aspect of the conversion is to improve the quality of the audio portion of the
immersive experience in a multiplex type theatre. Sound systems for cinema have evolved
over the decades and the trend continues as an ongoing effort to attract the paying viewer.
The surround sound systems used in today's Multiplex theatres can provide a degree of
"ambience" in the audio experience but these systems still lack the ability to create realistic
immersive audio.
From the time "talkies" were introduced, motion picture cinemas had "monaural"
sound systems, having only one loudspeaker located behind the center of the screen. The
sound experience in such a cinema was very one dimensional and flat, with no ability to
simulate sounds coming from directions other than the center of the picture. In order to
improve the audio experience, cinema designers and equipment suppliers experimented with
a variety of multiple loudspeaker ("multi-channel") schemes designed to immerse the
audience in a sound field which could add to the "suspension of disbelief desired by
filmmakers. One of the earliest attempts at multi-channel sound was the premier of Walt
Disney's "Fantasia" in 1939. Disney experimented with a number of sound system
loudspeaker configurations as outlined in an article by William E. Gariry and John N. A.
Hawkins published in the August 1941 issue of the journal of the SMPTE. The last two
versions of the Fantasound system, known as Mark K and X, used 5 loudspeakers and sound
from 3 separate tracks. The loudspeakers were positioned such that 3 were behind the screen
(i.e., left, center, and right) and one loudspeaker was in each rear corner. The two sets of
rear comer loudspeakers were switched in to supplement or replace the corresponding left
and right front loudspeakers at select times during the picture presentation. Unfortunately,
the war and economics cut short Disney's sound system experiments. In the early 1950's,
Cinerama brought multi-channel sound to the forefront again with 5 to 7 loudspeaker
channels located around the audience.
During the 19S0's there were several theatres equipped for the playback of multi-
channel sound, of which there were primarily two formats both using magnetic stripes printed
on the film. The CinemaScope 35mm film format provided four discrete channels, consisting
of 3 loudspeakers behind the screen and a monaural surround channel provided by several
small loudspeakers located on the side and rear walls of the cinema. These surround
loudspeakers provided a degree of "ambience" to the sound experience in combination with
the directional sound produced by the 3 screen loudspeakers, and thus added to the immersive
effects presented to the audience. The Todd-AO 70mm film format added two additional
loudspeakers behind the screen, Left Center and Right Center, between the center
loudspeaker and the left and right speakers.
In the 1970's, Dolby pioneered several advances in cinema sound, including extended
low-frequency sound (sub-bass), noise reduction, and Stereo Optical sound. Dolby Stereo
Optical provided 4 channels of sound (left, center, right, and mono surround) using an
encoding technique to store the analog soundtrack on two analog optically printed stripes on
the film. This became the standard for normal cinemas, and remains in use today in non-
digital cinemas.
In 1979, Dolby added to the immersive effects of cinema sound by developing stereo
surrounds, in which the left distributed loudspeaker channel could reproduce different sounds
than the right channel. But, the surround effects were still effectively ambience sounds, and
were unable to reproduce directionality with any precision due to the distributed
configuration of the surround loudspeakers.
In the 1980's, MAX® Corporation standardized on a 6-channel sound system with a
discrete surround sound configuration and a separate sub-bass channel for DVLAX® Theatres.
This type of system provides substantially better sound imaging by utilizing custom-designed
loudspeakers located in each rear comer behind the audience, each powered by a separate
audio channel. The immersive effects of this type system are much more impressive, and
allow the filmmaker the ability to position sound more precisely - directly in front of, in front
above, around, and behind the audience.
In 1987, Imax installed the first Digital Sound Reproducer in an IMAX Theatre. By
1990, uncompressed Digital Sound was available to all IMAX Theatres. Also in 1990, with
the release of the movie "Dick Tracy," CDS uncompressed digital sound on 35mm film was
introduced to the general cinema industry by a joint venture of Orcon and Kodak. Because
CDS was not compatible with standard optical sound on 35mm film, the CDS format was
discontinued soon thereafter.
Between 1992 and 1993, three systems of digital sound for cinema were released -
Dolby Digital, DTS, and Sony SDDS. All three of these formats utilized some form of
digital compression to reduce the storage requirements (on CD-ROM foT DTS) or to allow
the digital audio signal to be printed on the 35mm film (with Dolby Digital and SDDS)
without displacing the optical track as did the CDS system. While these systems use different
compression techniques —some considered "better sounding" than others - IMAX Digital
Sound remains the only uncompressed digital cinema sound format in general use today.
All three of the digital sound systems used in conventional 35mm and digital cinemas
make use of the same distributed side and rear surround loudspeakers to create a sense of
ambience for the film soundtrack. Even though these digital systems may sound "better" than
the older optical systems, sound immersion remains limited due to the inability of multiple
distributed loudspeakers to provide precise directionality and image placement.
Motion picture exhibitors have expressed interest in providing additional quality
improvements to mainstream motion pictures by adding a special, custom designed, smaller
scale Imax theatre to their multiplexes. This has proved popular with patrons and exhibitors,
but has not been widely adopted because of high costs associated with constructing the
adjunct theatre.
It is desirable to be able to provide mainstream multiplex theatres with the same
manner of widescreen presentation experience as large hall custom designed theatres, but at a
lower, more affordable cost There is a need to be able to economically convert an existing
mainstream multiplex motion picture theatre into a widescreen theatre that is qualitatively
superior in terms of projected image quality, field of view, and of a more realistic immersive
audio experience that does not exist in multiplex type theatres. As a result of having
overbuilt the number of multiplex theatres the economics of this situation dictates that
converting existing multiplex theatres makes better sense than building additional new
multiplexes with larger screen sizes. The following discussion of the inventive approach by
the applicant addresses Uiis need.
Summary of the Invention
The invention is a method of cost effectively converting an existing standard motion
picture theatre, such as the multiplex theatre that uses film/digital projection, to a highly
immersive, large field of view motion picture theatre. Hereinafter the term "multiplex
theatre" is used in a more general sense to represent all motion picture theatres that are: not
the Grand Theatre hall sizes of the 1920s, not the theatrical stage theatres, and not the IMAX
geometry theatre halls originally built for Imax presentations. The inventive method
includes:
• moving the motion picture screen closer to the audience to increase the field of
view; and
• employing projection means to improve the quality of images on the screen
such that the audience does not see unrealistic or non-natural image artifacts
which would occur by just simply magnifying the existing projected image.
In some situations, carrying out the first step may inadvertently block access to an
existing emergency exit door necessitating an additional step of moving a portion of the
screen to allow access to the emergency exits.
To cost effectively convert a multiplex theatre sound system so that a realistic audio
immersion experience is created may involve the following:
• changing the loudspeaker configuration to one that uses 5 discrete
loudspeakers with Proportional Point Source technology and one sub-bass
loudspeaker; and
• driving each loudspeaker from a separate sound channel; with
• the sound system using a 5.1 sound track that is mixed differently than
standard cinema 5.1 sound track and
• the sound system using uncompressed digital sound with a resolution of 16
bits OT greater.
Brief Description of the Drawings
Figure 1 is a plan view of a typical multiplex theatre.
Figure 2 is an elevation view of a typical existing theatre.
Figure 3 is a plan view of a multiplex theatre after conversion.
Figure 4 is an elevation view of a multiplex theatre after conversion.
Figure 5 is a plan view of a converted multiplex theatre illustrating a novel emergency
exit access system.
Figure 6 is an elevation view of a converted theatre illustrating a novel emergency
exit access system.
Figure 7 is a front view of the screen in a converted theatre illustrating the novel
emergency exit access system in a normal state.
Figure 8 is a front view of the screen in a converted theatre illustrating the novel
emergency exit access system in an activated state.
Figures 9a-9b are a plan view of a converted theatre and a front view of the screen
illustrating the position of the PPS speakers.
Detailed Description of the Drawings
Referring now to Figure 1, a plan view of a typical 35mm film and/or digital
multiplex theatre is depicted at 1. Theatre 1 includes a front projection screen 2, motion
picture projector 3, a theatre enclosure rear wall 4, a seating deck 5 upon which there are
seats for spectators 6. The distance dl indicates the distance from the centre of screen 1 to
the inner surface of rear wall 4. The space between the screen and the rear wall is occupied
by a screen support structure (not shown) and sound system speakers (also not shown).
Angle AOB represents the horizontal field of view of the motion picture theatre as seen from
a location coincident with the point of projection, O. In the case of Figure 1, this angle
equals approximately 45 degrees. This represents a minimurn horizontal field of view for
patrons in the theatre; as one sits closer to the screen the horizontal field of view increases. A
patron sitting at position X in Figure 1, for example, would have a horizontal field of view of
55 degrees, as is indicated by angle AXB. The widest possible field of view in a theatre such
as depicted in Figure 1 is indicated by the angle AZB representing a patron sitting in a seat in
the front row, and is equal to about 110 degrees. It must be noted however that in a typical
multiplex cinema theatre the visual quality of images when viewed from a close position, like
point Z in Figure 1 is not as good when seated further back. In the close-up seats unnatural
visual defects such as insufficient image resolution, film grain, visible pixels, blurred edges,
and image unsteadiness are more easily perceived. Generally, patrons in these theatres tend
to sit further from the screen when given the opportunity where image defects are less
apparent
Figure 2 illustrates an elevation view of multiplex cinema theatre 1. It can be seen
that screen 2 is less than the full height of the theatre with observable gaps above the upper
edge of the screen and below the lower edge of the screen. These gaps would be covered up
by dark curtains or similar observant material to help conceal the limited vertical extent of
screen 2. Angle COD represents the minimum vertical field of view in a theatre of this
geometry and is equal to about 20 degrees. As one moves closer to the screen, the vertical
field of view increases, as one would expect. At position X the vertical field of view is about
25 degrees while at position 2, it is about 50 degrees. It can be seen that seating deck 5 is
sloped at an angle of about 20 degrees in the rear portion of the theatre and about 15 degrees
in the section closer to the screen. This slope, or rake, of seating deck 5 allows each row of
seats to be located on a separate platform thereby giving patrons a clear vertical field of view
of the entire screen
The horizontal and vertical fields of view available to patrons in a typical multiplex
theatre are significantly below the capabilities of the human visual system, which is estimated
to have a recognizable horizontal field of view of 120 degrees and a vertical field of view of
about 70 degrees. The estimated perceptual field of view is about 200 degrees horizontally
and 13S degrees vertical.
Referring now to Figure 3, the same multiplex cinema theatre is shown after
conversion to an improved, more visually immersive motion picture theatre. Screen 2, shown
in outline, has been removed and replaced by a new, larger screen 10 which is now located at
a new distance, d2, from rear wall 4. Screen 10 extends &om wall to wall, and as shown in
Figure 4, extends from floor to ceiling. The hatched area in the lower part of seating deck 5
in Figure 3 represents seats that have been removed to accommodate the new screen aid
viewing geometry of the improved theatre. A new projector 7 replaces the standard multiplex
cinema projector and is capable of projecting images with superior quality in terms of
resolution, sharpness and steadiness.
The minimum horizontal field of view of the improved theatre is now about 55
degrees, while the rnirrLmum vertical field of view is about 30 degrees. At position X, the
horizontal field of view is about 75 degrees and the vertical field of view is about 40 degrees.
At position Z the horizontal field of view is about 130 degrees and the vertical field of view is
about SO degrees. To a viewer sitting at the seat closest to the screen centre, the new screen
position and size appears 115% larger than the conventional screen size. To the viewer
sitting at the position X in the theatre with the new screen position and size the screen size
appears to have increased 100%. To the viewer sitting at the rear most position of the theatre
with the new screen position and size the screen size appears to have increased 85%. The
viewer in position X, when the screen has been moved forward, experiences an increase in
image angular FOV of about 35% horizontally and 60% vertically. The increase in vertical
FOV is especially significant and is an improvement that until now has been largely
overlooked by the prior art traditional cinema system advances such as Cinerama which
concentrated on expanding horizontal FOV. The increased FOV, both vertical and
horizontal, is an important presentation improvement resulting from the inventive method of
theatre conversion.
It is possible to only increase the image fidelity of the projection system such that the
viewers see the same fidelity of image on the forward moved screen as when the screen was
positioned prior to the conversion. This would mean that viewers in the first few front row
seats in the converted theatre would experience the same quality of image prior to the
conversion that was already marginally low, hence, one reason viewers move further basic in
the theatre. The most evident image fidelity issues of front row viewing are lack of image
resolution, the presence of film grain artifacts becoming apparent, or in the ease of digital
projection, image pixels becoming apparent. Other factors only associated with conventional
film projectors that specifically contribute to image contrast MTF degradation are film
transport unsteadiness and softening of film image due to heat pop of the film, la the theatre
conversion front row seats have beer, removed, so there are fewer seats in the theatre. To
give front row seats a more acceptable viewing experience the image projection fidelity can
be further increased so that the front row viewers now get the same or better image quality as
the viewers seated further back from the screen prior to the conversion.
In the preferred embodiment one type of projector that uses film with a larger image
area and does not suffer from image unsteadiness or film heat pop associated with
conventional cinema film projection systems is the rolling loop projection system.
The combination of improved image quality on the screen with increased horizontal
and vertical fields of view significantly improves the sensation of visual immersion in the
images. Applicant has confirmed through research studies in perception and cinema viewer's
preferences, the improvement in the presentation of the converted theatre is significantly
better than the presentation in a standard multiplex cinema theatre.
In addition to significantly improving image quality and enhancing the feeling of
immersion in 2D images, the wider fields of view provided by the inventive method of
theatre conversion is necessary for proper and realistic immersive experiences of 3D motion
picture presentations.
In some multiplex theatre designs emergency exits are at the screen end of the theatre
on the side wall. These exits could be blocked by the new position of the screen in a
converted theatre. This situation may not be acceptable "by local safety regulations. The
inventive conversion method addresses this possibility by inclusion of an emergency screen
access system consisting of a system door and means for automatic activation of said door.
Figures 5 through 8 illustrate one embodiment of such a system.
Referring now to Figure 5 and 6, an emergency exit door 21 which was located in
front of original screen 2, shown in outline, is now located behind new screen 10. Motion
picture screen 10 consists of a perforated, pliable projection surface material such as vinyl
which is supported and stretched by a frame (not shown) located behind the projection
surface. Figure 7 illustrates schematically now one comer of projectior. screen 10 is not
fastened rigidly to a supporting frame, but is held in place by the magnetic attraction between
metal rods 25 in the edges of screen 10 and electromagnetic means 26 attached to the wall
and floor of the converted motion picture theatre. A cable 23 is attached to the rear corner of
the projection surface of screen 10. The other end of cable 23 is attached to a counterweight
24 after first passing over a pulley 22 attached to the rear wall surface 4. In an emergency
situation, an automatic activation means sends a signal to electromagnets 22 switching them
off thereby removing the magnetic force which had been holding tire metal rods firmly
against the wall and floor of the theatre. The comer of the projection surface of screen 10 is
then pulled backwards and upwards by the counterweight as it falls by gravity towards the
ground. Figure S depicts the system door to the emergency exit in an activated position with
the comei of screen 10 pulled upwards and backwards and counterweight 24 resting on the
ground. An iUurninated sign is shown at 27 directs patrons to the newly revealed emergency
exit 21. Winching means, not shown, is used to pull up the counterweight so that the system
and screen can be reset after it has been activated.
The activation signal may be effected by a number of activation systems, separately or
in parallel, including a mechanical swing gate crash bar located at the bottom aisle stairs,
pushing or applying pressure to the screen surface, by a signal from the building emergency
alarm system, a manual release button at the usher station, or by a patron activated motion, IR
or touch pad sensor near the vicinity of the corner of screen.
In addition to the potential necessity of using the emergency screen access system
diere are other negative consequences associated with the inventive method of multiplex
theatre conversion that must be remedied or accepted including the creation of a large sound
cavity behind the new screen assembly, and the necessity to remove a number of seats near
the front of the theatre which are too close to the new screen for effective viewing. The first
problem is addressed by the provision of a sound absorbing acoustic wall behind the new
screen, that can be built inexpensively because it need not be a load bearing structural wall.
If the sound barrier is forward of the theatre exit door an additional door would have to be
built into the sound barrier. The second problem, seat removal, and the loss of revenue
associated with those seats, is not overly detrimental to the success of the multiplex complex
because a higher admission price can be charged for the remaining seats. In addition, it is
believed that the premium quality and unique immersive experience offered by the new
motion picture will lead to a higher, and sustained, level of theatre occupancy over its
operating lifetime.
The conversion of a 35mm film and/or digital projection multiplex theatre is not
limited to the steps outlined above but can include further steps such as: tilting the screen
forward or backwards with respect to the audience to increase the screen surface area in the
vertical dimension or to compensate for keystoning or light reflection back to the audience;
curving the screen in the vertical direction to provide a compound curved screen; or
modifying the ceiling to provide additional vertical height for the new screen.
The conversion is also not limited to improving the quality of the visual experience
but also converting the sound system to give a significantly more realistic and immersive
audio experience. A truly immersive audio environment, similar to what the audience
experiences in an IMAX® Theatre, is one in which the sound system has the ability to
realistically position sound images in front of, around, and behind the audience. The
converted sound system must be reasonably cost effective and at the same time create a
realistic immersive audio experience for the majority of seats in the theatre. A conversion
that does this is described below.
The theatre sound system is setup with a loudspeaker configuration as illustrated in
figures 9a and 9b. Figure 9a is a plan view of the loudspeaker positions in a converted
theatre and figure 9b is a front view of the loudspeakers behind the screen in a converted
theatre. There are 5 loudspeakers 101,102, 103, 104, and 105, each driven from a separate
audio source, and each with appropriate amplification and equalization. There is a 6th Sub-
Bass Loudspeaker assembly 106 consisting of several sub-woofer elements grouped together
that re-pTOduce the low-frequency sound derived from the 5 audio channels. Powered with
sufficient amplification these loudspeakers provide realistic sound levels for low-frequency
sounds such as rocket launches, earthquakes, and explosions. Each audio channel is fed
uncompressed digital sound with a resolution of 16 bits or greater from the Digital Sound
Reproducer. The Digital Sound Reproducer is normally positioned in the sound rack 120 in
the projection booth.
The loudspeaker positions in the theatre are referred to as: Left Rear 101, Left Screen
102, Center Screen 103, Right Screen 104, Right Rear 105 and the Sub Bass position 106.
Loudspeakers 102, 103, and 104 in the front are positioned between the newly installed sound
barrier 110 and the screen 10, part way between the screen base and top. Sub bass 106 is
located between the sound barrier 110 and the screen 10 under Center Screen 103. The
screen is perforated with tiny holes to let the sound through yet obscure speaker visibility.
The complete sound system is designed to cover the entire audio spectrum and provide
sufficient sound level within the theatre.
Loudspeakers 101, 102, 103, 104, and 105 are designed with Proportional Point
Source (PPS) Technology. The principles of the physics used in PPS Loudspeaker
technology is known to those skilled in the art In general terms PPS Loudspeaker
technology refers to the ability of a loudspeaker to direct proportionately more sound energy
to seats farther away than that directed to the closer seats from a single or virtually single
source position. Hereinafter this will be referred to as "PPS technology." In order to achieve
optimum sound dispersion^ PPS type loudspeakers must be designed for the specific theatre
geometry. MAX® Loudspeakers used in this conversion are designed with PPS
Technology, using horns with asymmetrical dispersion patterns specifically designed to
provide balanced sound distribution for multiplex cinemas having the appropriate geometry.
During installation each loudspeaker is placed, aimed, and aligned to position the
sound dispersion pattern for maximum immersive effect. The alignment process involves use
of computer aided design to determine the optimum loudspeaker "pointing angle" for each of
the 5 loudspeakers in the theatre. Then, with the use of LASER alignment tools, the
loudspeaker can be aimed to match the predetermined "pointing angle." A cinema sound
system using PPS technology properly configured and equalized to the accepted industry
standard, allows all theatre patrons to perceive sound from all channels as having essentially
the same volume level and tonal quality. Thus, the sound "image" desired by the filmmaker
is reproduced for the entire audience area. Surround sound systems that do not employ the
use of PPS-rype loudspeakers provide balanced sound, or a "sweet spot" for only a few seats -
generally near the center of the theatre. Other patrons may hear only one or two loudspeakers
predominantly, with little contribution from the other sound channels.
There are three significantly differentiating aspects of the converted sound system
with respect to multiplex cinema sound systems. Not only has this type of immersive
surround sound system conversion not been done before in multiplex theatres, there are
differences that make the invented sound system conversion process truly unique.
The first differentiating aspect is that the sound system, as shown in figures 9a-9b,
uses discrete loudspeakers in the rear corners of the theatre with separate sound channels to
provide the greater surround sound imaging capability. AH conventional surround systems
used in multiplex cinemas make use of distributed side and rear surround loudspeakers to
create a sense of ambience but these lack the ability to provide precise sound directionality
and sound image placement.
Secondly, in a sound system with 5 discrete PPS type loudspeakers and sound
channels it becomes possible to place sound images in front of, around, and behind the
audience. To optimize sound placement in a 5 channel discrete source sound system the 5
sound tracks must be re-mixed in order to provide the audience with a truly more realistic
immersive audio experience. Multiplex Cinemas have not configured their sound system
setup in this way before.
The third aspect relates to the Digital Sound Reproducer. As previously noted, other
multiplex cinema sound systems utilize either optical analog audio tracks printed on the film,
or one of three digital sound formats - all of which compress the digital audio by significant
amounts in order to fit the storage/playback media. The Digital Sound Reproducer within the
converted theatre uses uncompressed digital sound with a resolution of 16 bits or greater to
provide all the audio resolution and dynamic range intended by the filmmaker and the film
sound engineer.
The MAX multiplex theatre converted sound system with its unique Digital Sound
Reproducer will provide very high quality digital audio surpassing all other available cinema
sound formats in fidelity, resolution, dynamic range and sound image placement capability.
The result is sound unrivalled in achieving the goal of a realistic immersive cinema
experience, and the "suspension of disbelief desired by filmmakers.
The result of a multiplex theatre converted using some or all the steps described above
creates for the audience a substantially improved realistic visual and audio immersion
experience for 2D and 3D motion picture presentations. To date, this type of conversion has
not been done before in multiplex theatres.
The foregoing is provided for purposes of illustrating, explaining, and describing
exemplary embodiments and certain benefits of the present invention. Modifications and
adaptations to the illustrated and described embodiments will be apparent to those skilled in
the relevant art and may be made without departing from the scope or spirit of the invention.
WE CLAIM :
1. A method of converting a multiplex theatre hall into an immersive motion picture
theatre hall, comprising:
a. providing a multiplex theatre hall having a left wall, a right wall a front wall, and a
rear wall and comprising:
i. a motion picture projector for projecting an image;
ii. a first projection screen;
iii. a second projection screen comprising a left section, a central section, and a
right section and positioned closer to the rear wall than to the front wall, the first and second
screens heing configured for displaying the same presentation format of images;
iv. a set of loudspeakers; and
v. at least first and second patron seat locations;
b. changing the set of loudspeakers so that it comprises at least five discrete
loudspeakers and at least one sub-hass loudspeaker assembly, (i) a first discrete loudspeaker
of the set of loudspeakers being positioned adjacent the left section of the second projection
screen, (ii) a second discrete loudspeaker of the set of loudspeakers being positioned adjacent
the center section of the second projection screen, (iii) a third discrete loudspeaker of the set
of loudspeakers being positioned adjacent the right section of the second projection screen,
(iv) a fourth discrete loudspeaker of the set of loudspeakers being positioned adjacent the left
and front walls, and (v) a fifth discrete loudspeaker of the set of loudspeakers being
positioned adjacent the right and front walls, (vi) each of the at least five discrete
loudspeakers receiving signals via a separate audio channel, and (vii) at least one of the
loudspeakers of the set of loudspeakers being (A) located closer to the first patron seat
location than to the second patron seat location and (B) configured to direct proportionally
more sound energy to the second patron seat location than to the first patron seat location;
c. aiming the at least five discrete loudspeakers so that patrons sitting at the first and
second seat locations perceive sound from all audio channels as having essentially the same
volume level and tonal quality; and
d. projecting the image over a major portion of the second projection screen,
increasing vertical field of view of the image for patrons sitting at the first and second seat
locations, thereby creating an immersive motion picture theatre hall.
2. A method according to claim 1 further comprising transmitting, from a digital sound
reproducer to each of the at least five discrete loudspeakers, uncompressed digital sound with
resolution of at least sixteen bits.
3. A method according to claim 2 further comprising locating the digital sound
reproducer and a projector in a projection booth within the multiplex theatre hall.
4. A method according to claim 1 in which the second projection screen is perforated.
5. A method according to claim 1 further comprising mixing differently a standard
cinema 5.1 sound track so as to provide signals to the at least five discrete loudspeakers.
6. A method of converting a multiplex theatre hall into an immersive motion picture
theatre hall, comprising:
a. providing a multiplex theatre hall having a left wall, a right wall, a front wall, and a
rear wall and comprising:
i. a motion picture projector for projecting an image;
ii. a first projection screen;
iii. a second projection screen comprising a left section, a central section, and a
right section and positioned closer to the rear wall than to the front wall, the first and second
screens being configured for displaying the same presentation format of images;
iv. a set of loudspeakers; and
v. at least first and second patron seat locations;
b. providing a sound absorbing acoustic barrier between the projection screen and the
rear wall;
c. changing the set of loudspeakers so that it comprises at least five discrete
loudspeakers and at least one sub-bass loudspeaker assembly, (i) a first discrete loudspeaker
of the set of loudspeakers being positioned adjacent the left section of the second projection
screen, (ii) a second discrete loudspeaker of the set of loudspeakers being positioned adjacent
the center section of the second projection screen, (iii) a third discrete loudspeaker of the set
of loudspeakers being positioned adjacent the right section of the second projection screen,
(iv) a fourth discrete loudspeaker of the set of loudspeakers being positioned adjacent the left
and front walls, and (v) a fifth discrete loudspeaker of the set of loudspeakers being
positioned adjacent the right and front walls, (vi) each of the at least five discrete
loudspeakers receiving signals via a separate audio channel, and (vii) at least one of the
loudspeakers of the set of loudspeakers being (A) located closer to the first patron seat
location than to the second patron seat location and (B) configured to direct proportionally
more sound energy to the second patron seat location than to the first patron seat location; and
d. aiming the at least five discrete loudspeakers so that patrons sitting at the first and
second seat locations perceive sound from all audio channels as having essentially the same
volume level and tonal quality, thereby creating an immersive motion picture theatre hall.
7. A method according to claim 6 further comprising positioning the at least one sub-
bass loudspeaker assembly between the sound absorbing acoustic barrier and the central
section of the second projection screen.
8. A method according to claim 7 in which the at least one sub-bass loudspeaker
assembly comprises a plurality of sub-woofer elements configured to reproduce low-
frequency sound derived from signals of the audio channels for the at least five discrete
loudspeakers.
9. A method according to claim 6 further comprising mixing differently a standard
cinema 5.1 sound track so as to provide signals to the at least five discrete loudspeakers.
10. A method of converting a multiplex theatre hall into an immersive motion picture
theatre hall, comprising:
a. providing a multiplex theatre hall having a rear wall and comprising:
i. a first projection screen positioned a distance Dl from the rear wall;
ii. a set of loudspeakers; and
iii. at least first and second patron seat locations;
b. providing a projection screen positioned a distance D2 from the rear wall, where D2
is greater than Dl, by either (i) moving the first projection screen or (ii) erecting a second
projection screen;
c. providing a sound absorbing acoustic barrier positioned a distance D3 from the rear
wall, where D3 is less than D2;
d. positioning at least some of the set of loudspeakers a distance D4 from the rear
wall, where D4 is greater than D3 and less than D2, such loudspeakers receiving signals via
separate audio channels: and
e. aiming the set of loudspeakers so that patrons sitting at the first and second seat
locations perceive sound from all audio channels as having essentially the same volume level
and tonal quality, thereby creating an immersive motion picture theatre hall.
11. A method of converting a multiplex theatre hall into an immersive motion picture
theatre hall according to claim 10 in which: D3>D1.
12. A method of converting a multiplex theatre hall into an immersive motion picture
theatre hall according to claim 10 in which: D2-D3