WO2006103301A1

WO2006103301A1 - Device for coupling to a standard two-dimensional reproduction unit and obtaining a stereoscopic reproduction

Info

Publication number: WO2006103301A1
Application number: PCT/ES2005/000292
Authority: WO
Inventors: Juan DOMÍNGUEZ-MONTES
Original assignee: Dominguez-Montes Juan
Priority date: 2005-03-31
Filing date: 2005-05-23
Publication date: 2006-10-05
Also published as: ES2284313B1; ES2284313A1

Abstract

The invention relates to a device for coupling to a standard two-dimensional reproduction unit and obtaining a stereoscopic reproduction. The inventive device comprises: a lenticular screen (1) which can move laterally from left to right in relation to a flat diffusing surface (3, 4) on which the two images forming a stereoscopic pair are reproduced, and a parallax barrier (2) which can move from left to right and from front to back in relation to the aforementioned diffusing screen (3, 4), following the movement of the observer's head. The parallax barrier (2) comprises bars having a width that is approximately equal to half the width of the cylindrical lens of the screen that can move transversely and longitudinally in relation to the diffusing surface (3, 4).

Description

DEVICE FOR COUPLING AN ORDINARY TWO-DIMENSIONAL PLAYER AND GET A REPRODUCTION

STEREOSCOPIC

The device object of this invention reproduces a stereoscopic image for a single observer, which can freely move its head and simultaneously a two-dimensional image to the other observers and is constituted by a lenticular weft and a special mobile parallax barrier that form a single set that It can be attached to any two-dimensional flat screen or replace an ordinary rear projection screen.

BACKGROUND OF THE INVENTION

Here the term stereoscopic is used to designate the systems that use only two images in reproduction that are captured from two points horizontally separated from each other.

There have been many procedures to get a different image to each eye. Given the object of this invention, only some of the known procedures that perform this function will be analyzed here without the use of glasses or any other device in the eyes of a single observer and in which the reproduction is carried out by projection or by some other device specially designed for this purpose.

The three-dimensional concepts on which these devices are based can be found in the book "Three - Dimensional Imaging Techniques", Takanori Okoshi; Academic Press, New York, San Francisco, London 1976. The specific topics discussed here have been studied by Reinhard Bórner in "Autostereoskopic Fiat Monitors and Projection System" and by Siegmund Pastoor and Matthias Wopking in "A review of current technologies" of "Heinrich - Hertz - Instituí "(Berlin). The simplest device for stereoscopic projection reproduction is that consisting of two projection lenses whose optical centers are separated from each other by a distance approximately equal to that which separates the pupils from the eyes of the observer. The image corresponding to this eye is projected by the left objective and by the right

The corresponding to this other. The projection is made frontally on a lenticular frame in whose focal plane a diffusing screen is located. The observer must place his left eye within a vertical rectangle whose base is the pupil of the left projection target and similarly the right eye in the rectangle corresponding to the right target.

There are also other frontal projection devices that instead of lenticular weft use surfaces formed by small catadioptrics consisting of two or three flat mirror surfaces perpendicular to each other. Vertical diffusion is achieved by conveniently undulating one of the reflector planes.

A variant in the frontal projection system interposes a semi-transparent sheet forming forty-five degrees with the surface containing the catadioptric or the lenticular weft.

The most important disadvantages of these devices are:

- Stereoscopic vision is obtained only when the observer places each eye within a vertical rectangle. Any other observer who does not place his eyes inside the previous rectangles will not see any image.

- The monitoring of the observer's head is achieved by moving the projection objectives or the intermediate reflector sheet in the same direction, direction and speed as the observer. For this, it is necessary to put into play a great mechanical power, necessary to overcome the inertia of the projectors at high speed and with the required precision. - Since it is a frontal projection, the brightness of the projectors on the lenticular frame forces a relatively complex inclined projection.

Rear projection eliminates the latter inconvenience.

The rear projection device also uses a system of two projection lenses, one for each image, separated from each other by a distance approximately equal to that which separates the eyes from the observer. The rear projection is performed on a lenticular weave in whose focal plane a translucent screen is placed. Said translucent screen together with a second lenticular frame form a device analogous to that described above for frontal projection.

When observer tracking is done by moving the projectors or an intermediate reflecting surface, the drawbacks are the same as for the previous frontal projection system. However, it is necessary to add the impossibility of achieving a sufficient adjustment between frames due to the fact that the manufacturing tolerances of the components are not controllable.

When the movement of the observer is from left to right, the monitoring of the observer's head can be carried out by moving one frame laterally with respect to the other. When the observer approaches or moves away, it would be necessary to zoom in or out of the plot with respect to the translucent surface that causes a blur that makes effective monitoring impossible.

There is also a rear projection procedure on a translucent surface and between it and the observer an interposed lenticular weft. The projection is made from a single projection objective. The projected image consists of thin vertical strips, -TO-

the pairs for one of the images and the odd ones for the other, intertwined with each other.

The delicate precision in the size and in the placement of the strips on the lenticular weave are hardly achievable with the projectors currently on the market, together with the change of scale according to the projection distance together with the inevitable optical aberrations of the lens prevent easy setting in the market for this device.

Stereoscopic projection reproduction devices are only manufactured as specialized equipment for this purpose and without being able to overcome the above-mentioned drawbacks.

On the contrary, the device object of this invention allows the use of any ordinary projection equipment for stereoscopic reproduction. The device object of this invention can be used as a rear projection screen with ordinary projectors and allows stereoscopic vision for a single observer and two-dimensional for the rest.

There are other stereoscopic reproduction devices for a single observer on flat screens usually of liquid crystal that can be grouped into two different types.

In the first place, those teams, which direct each of the images to the corresponding eye of a single observer by means of a special backlight system. Since the backlight system is not the standard used for ordinary use of two-dimensional reproduction, these devices need to be specially manufactured for this purpose.

Secondly, equipment that uses other additional components such as lenticular or prismatic frames and / or parallax barriers and where the images appear discriminated by their different situation and therefore divided into thin vertical strips, which requires a very delicate fit between these strips and these components. This forces to specialize these components for each type of liquid crystal and commercialize the product as an equipment specially designed for stereoscopic reproduction.

In both cases these devices are usually prepared for ordinary two-dimensional reproduction although for this exclusive use they are very expensive.

Against these, the device object of this invention can be coupled to any ordinary two-dimensional flat screen player achieving a stereoscopic vision for a single observer and two-dimensional for the rest.

The device described in this invention achieves this objective because it uses a single lenticular weft and a single special parallax barrier that moves relative to the other in accordance with the movement of the observer, of very easy construction because the barrier can be manufactured by Printing which allows a very precise adjustment with the plot since manufacturing tolerances are easily controllable. The movement of the barrier travels short distances and due to its light weight it only needs to put into play a small mechanical power. The monitoring of a single observer both from left to right and from front to back does not cause blur because the optical power of the mobile parallax barrier is zero. The rest of the observers can see a two-dimensional image either corresponding to the right eye or the left eye depending on its location because the entire width of the cylindrical lens component of the frame is occupied by image. The only necessary adjustments are between the lenticular frame and the special parallax barrier and are independent of the image reproduced by which the device can be used as overhead projection screen or attachable to any flat surface reproducing three-dimensional images.

DESCRIPTION OF THE INVENTION

The model object of this invention is formed by three components. A lenticular frame and a parallax barrier that can be moved relative to each other and a reproduction screen of the two two-dimensional images belonging to a stereoscopic pair.

The device that produces the movement between the parallax barrier and the lenticular weave in accordance with the movement of the observer is not an object of this invention. This device is composed of two electromechanical elements fed by an electronic system that in turn receives the signal from a detector of the position of the observer's head. All this has been described as part and object of the PCT patent number ES2004 / 000394.

To facilitate exposure, we will first explain the way in which these components are normally used. Secondly, the different way that each of these elements performs its function in this invention and finally the arrangement of these elements in the device object of this invention will be exposed.

The classic lenticular weft consists of a series of converging cylindrical lenses, identical to each other, arranged with their parallel optical axes contained in the same plane, placing them side by side and in contact with each other. The thickness of the lens is usually made equal to its focal length within the material from which it is constructed. Given the small focal length with respect to the observation distance it is assumed that the images are always focused on their focal plane. That is why the second face of the plot is a flat surface It occupies its focal plane where the images to be observed are arranged through the cylindrical lenses.

When the lenticular weave is used for the reproduction of three-dimensional images, the different images are located on this flat surface, each occupying a thin vertical strip. In the width corresponding to that of a cylindrical lens, dozens of different image strips can be placed depending on this number of the width of the lens and the available print or projection quality.

Both in ordinary three-dimensional reproductions by impression and in stereoscopic reproductions by projection, each of the images occupies a single vertical strip of a width that is usually a few tenths of the width of the cylindrical lens.

On the contrary, in the system object of this invention each of the images occupies a strip of a width approximately equal to half the width of the cylindrical lens, that is, the width of the cylindrical lens is totally occupied by only two images.

The vertical line that separates these two images is placed in such a way that at the observation distance this line is focused on a vertical line that passes through the midpoint between the pupils of the observer's eyes. As the barrier can be manufactured by printing this objective is easily attainable.

In this way, from the points located to the left of this line, the left image will be seen and from the points located to the right of this line the right image.

Only the observer or observers who place this line between their eyes will obtain stereoscopic vision. Normally he will be a single observer since a second observer should place his eyes exactly above or below the eyes of the first one which is normally difficult.

The rest of the observers will see with both eyes the same image, that is, an ordinary two-dimensional image.

To achieve that in the focal plane of each cylindrical lens two unique strips of images belonging to a stereoscopic pair are reproduced, two projection lenses are arranged.

Through each of these projection objectives an image is projected on a translucent screen located in the focal plane of the lenticular plot.

Between the projection objectives and this translucent screen is a parallax barrier composed of opaque and transparent alternative vertical bars of the same width. This width is approximately equal to half the width of the component cylindrical lens of the lenticular weft.

In this way, by properly positioning the projection objectives, each one of them generates an image strip for each cylindrical lens of a width approximately equal to half the width of the lens, each strip separated from the contiguous one of the same image by a dark bar of the same width as that of the projected image.

It is easy to achieve that the bars corresponding to one image remain interlaced with the bars corresponding to the other image. The precision adjustment between the frame and the barrier can be easily carried out if the barrier is obtained by printing acting on the scale of the latter.

If the observer moves from left to right or vice versa, the parallax barrier will move with respect to the plot from right to left or vice versa a sufficient distance for the observer to see the corresponding image with each eye. No special adjustments are needed between frame and barrier with the reproduced images.

If the observer moves from front to back or vice versa, the parallax barrier will move with respect to the diffusing surface analogously from front to back or vice versa.

It is important to emphasize that none of these movements of the barrier, necessary for the monitoring of the observer, produces blurring of the image with respect to the lenticular plot, as it has been explained that occurs in other systems, because in the device object of this invention the element Mobile is a parallax barrier whose optical power is zero.

The barrier is very light because it is an impression on a material as light as desired and, consequently, the mechanical power necessary for its movement is small.

In a first and second variant, the polarized filter projectors are placed linearly or circularly and the parallax barrier bars are constructed with the same filters. Even and odd bars will have polarization directions perpendicular to each other in the case of linear polarization and dextrógira and levógira when the polarization used is circular.

In a third variant it can also be reproduced in the modality known as anaglyphs. In this case an objective will project the image of a color for example red for one and for the other with the color green, blue or other colors in the absence of red and the bars of the parallax barrier will have the colors red and blue (or green) alternately. In a fourth and fifth variant the two projection lenses can be replaced by a single one and the two images will each be projected with a different polarization characteristic either multiplexed in time or by any other procedure.

In a sixth variant, the projection in the anaglyph modality can be done through a single objective belonging to an ordinary color projector in which the red color is reserved for an image and the green, blue or other color without red for The other.

In a seventh variant the images are reproduced by projection in horizontal strips, reserving the even strips for one image and the odd ones for the other. The parallax barrier consists of a mosaic of opaque and transparent rectangles. The rectangles belonging to the even horizontal rows are displaced from the odd ones by the width of the rectangle that is approximately equal to half the width of the cylindrical lens component of the frame. In both even and odd rows, the rectangles have a height approximately equal to the height of the horizontal strips of images.

To monitor the observer, the polarized parallax barrier, colored or composed of a mosaic of rectangles, will also move from left to right and from front to back, as in the first case of the opaque and transparent barrier and two projectors.

If the lateral movement of the observer is followed with sufficient precision, there is a margin of distance from front to back within which the vision remains stereoscopic. If the observer stays within this distance, the follow-up can be dispensed with from front to back or vice versa.

When the observer's follow-up is ignored from front to back the parallax barrier will not need this movement either and in this In this case, it can be placed between the projection screen and the lenticular frame because for the follow-up of the head, a relative movement from left to right between the lenticular frame and the barrier will suffice and this displacement does not cause blur. These arrangements constitute four other variants of this invention.

In other variants, the diffusing surface may be the flat surface of an ordinary color image player or specially designed for stereoscopic vision, discriminating the images by linear or circular polarization.

If, as before, it has been explained in cases where the front-to-back follow-up can be dispensed with and if the movement from left to right of the observer is maintained within a distance equal to half of the distance between his eyes, the lateral follow-up also It can be avoided what allows the lenticular weave and the parallax barrier to be joined together and form a single element. This constitutes a new variant of this invention.

When the thickness of the lenticular weft is equal to its focal length,

The diffuser screen together with the parallax barrier, which is assumed to be negligible thickness, can be supported on the flat surface of said frame and the cylindrical lenses will be oriented towards the observer. This arrangement manages to ensure the parallelism between the plot, the parallax barrier and the reproductive surface.

In another arrangement, the face containing the cylindrical lenses faces the flat surface composed of diffuser screen and parallax barrier, leaving a free space between them that prevents friction and facilitates the observer's left to right tracking.

In a last variant according to the size of the exit pupil of the projection objectives it may be convenient in some cases their reduction by diaphragm and / or increasing the size of the opaque bars against the transparent ones in the parallax barrier.

All these variants are objects of this invention.

In short, the object of this invention is a device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction characterized by a lenticular weft capable of moving laterally from left to right with respect to a flat diffuser surface where the two component images of a component are reproduced. stereoscopic pair and a parallax barrier with the ability to move from left to right and from front to back with respect to the diffuser screen according to the movement of the observer's head.

BRIEF DESCRIPTION OF THE FIGURES

Figures 1, 2, 3 and 4 serve to show some background of the invention and highlight its main drawbacks the remaining figures 5, 6, 7, 8, 9, 10, 11, 12 and 13 deal with the device object of this invention.

Figure 1 serves to show the behavior of an ordinary lenticular frame.

Figure 2 shows a simple frontal projection procedure.

Figure 3 shows a simple rear projection procedure.

Figure 4 shows the fields of view of the procedures shown in Figures 2 and 3.

Figure 5 shows the fields of vision in the device object of this invention. Figure 6 shows in plan the object of this invention with two projection lenses and a parallax barrier with opaque and transparent bars.

Figure 7 shows in three dimensions the plan image shown in Figure 6.

Figure 8 shows in plan the object of this invention with a single projector or two located in the same vertical.

Figure 9 shows in three dimensions three variants of the object of this invention shown in plan in Figure 8 with two projection objectives located in the same vertical to which polarized filters, linearly or circularly, or colored and a parallax barrier in which even and odd bars are also polarized or colored filters.

Figure 10 shows in three dimensions four different variants of the object of this invention shown in plan in Figure 8 with a single projection objective and four different ways of differentiating the image, by linear or circular polarization, by color and by its horizontal situation to which correspond four different types of parallax barriers. The barrier is located between the reproduction screen and the projector lens and the observer's tracking is from left to right and from front to back.

Figure 11 shows in plan the object of this invention with a single projection objective and the parallax barrier located between the lenticular frame and the projection screen allowing only the observer's left to right tracking.

Figure 12 shows in three dimensions the object of this invention shown in plan in Figure 11 and its four possible variants, differentiating images by linear or circular polarization, color or position and their corresponding parallax barriers.

Figure 13 shows the four variants of discrimination of images by linear or circular polarization by color or position and their corresponding parallax barriers with a flat screen of ordinary reproduction or specially designed for polarization reproduction and head tracking of the left observer to the right or vice versa.

DETAILED DESCRIPTION OF THE FIGURES

Figure 1 shows a lenticular frame 5 with the face of vertical cylindrical lenses 52 oriented towards the observer represented by its eyes 01, 02 and with the other flat face 51 where several images are printed or projected. Each image occupies a thin vertical strip 511, ... 517 for each lens located in the focal plane 51 of the cylindrical lenses. In a width equal to the width of the cylindrical lens a strip of each image is placed. Through each of the cylindrical lens components of the frame, different image strips can be observed. Each strip will be viewed from a different viewing angle. In this figure 1 it can be seen that from the eye 01 located at the angle 535 the image strip 515 is observed in each lens, that is, the entire frame 5 will be observed in the whole frame. Analogously with the eye 02 the image 3. In this way the vision of an orthoscopic three-dimensional image can be obtained along the angle 521. The same occurs for the angle 522 and 523 corresponding to the lobes of left and right vision of the frame lenticular

Figure 2 shows the lenticular frame 5 of Figure 1 to which a diffuser screen 6 has been added in its focal plane that serves for the reproduction of a stereoscopic image by frontal projection. Objectives 71 and 72 project images on the lenticular frame 5 corresponding to the left eye 01 and right 02. Each cylindrical lens generates two vertical strips on the diffuser screen 6. One strip will correspond to the image of the left eye and another strip to the image of the right eye. After the light diffuses on that screen 6, the light rays will again cross the lenticular frame, in the opposite direction, and will form two viewing rectangles 711 and 712, from which the images corresponding to the left and right eyes can be observed. If the observer places eyes 01 and 02 within these rectangles, he will see a stereoscopic image. If you get out of these rectangles you will lack vision. To follow the movement of the observer from left to right 921, 922 and from front to back 911, 912 the pair of projection objectives will move in the direction and direction 821, 822, 811, 812 according to the movement of the observer. This monitoring requires considerable mechanical power due to the inertia of the projectors, the high acceleration of the observer movements and the required precision. To avoid the brightness of the projectors on the cylindrical lenses of the lenticular weft, the inclined projection can be used. These drawbacks prevent the easy commercialization of this frontal projection system.

Figure 3 schematically shows a rear projection system. Objectives 71 and 72 project the two component images of a stereoscopic pair onto a lenticular frame 501. The lenticular frame generates an image strip for each projector and lens on the diffuser screen 6. Another lenticular frame 502 generates in a similar way to the frontal projection shown in Figure 2 the viewing rectangles 711 and 712 within which the eyes 01 and 02 of the observer. If the observer moves in the direction and direction 921, 922, 911, 912 leaving these viewing rectangles it will be necessary to move the projectors in the direction and direction 821, 822, 811, 812 so that it continues with stereoscopic vision Io that requires have a great mechanical power due to the inertia of the projectors and the speed of displacement. To follow the displacements from left to right 921, 922 of the observer, the frame 501 can also be moved with respect to 502, but for the monitoring of the movements of the observer from front to back 911, 912 the lenticles should separate from each other, which causes a blur between the image and the cylindrical lens that invalidates this solution. On the other hand, the quality of reproduction requires that the width of the lenticles be very small and that both lenticular frames be very precisely located opposite each other along the entire frame which imposes a precision and adjustment in their position which, in In general, it is above the controllable tolerances in the manufacture of these elements.

Figure 4 shows in detail the vision trapezoids 00, 021, 022, 023 and 00, 012, 013, 011 within which the observer must place his eyes 01, 02 to achieve a correct stereoscopic vision in the devices shown in the Figures 2 and 3. In this figure 4 it is shown that there is only one pair of vision trapezoids per view lobe of the lenticular weft, one for each image, each one reproduced in an image strip 11, 12 by lenticle Outside these trapezoids the observer lacks vision.

Figure 5 shows the behavior of the lenticular weft in the device object of this invention in which the width of the strips 11, 12 of each image on the reproduction screen 3 occupies half the width of the cylindrical lens. The vision trapezoids 00, 021, 022, 023 and 00, 011, 012, 013 occupy all possible viewing space. The observer 01, 02 will only obtain the stereoscopic vision by placing the midpoint of his eyes at 00 ± 0102/2. If the observer moves away from this vertical line of vision, he will continue to see a two-dimensional image 11, 12. The same will happen for the rest of the observers who will also see a bldlmenslonal image contrary to what occurs in the devices shown in Figures 2, 3 and 4 lacking vision. Also shown in this figure are the two ways of using the lenticular weft in the model object of this invention. Well with the face of cylindrical lenses 11 oriented towards the observer in frames whose thickness is equal to the focal length within the material, as is the case of most commercialized lenticular frames and with the diffuser surface 3 flat in the focal plane of the frame. This first arrangement ensures the focal length and parallelism of the image reproduced on the diffuser screen 3 in the lenticular frame 1. Or with the flat face 12 towards the observer Io leaving an air gap between the lenticular frame 1 and the diffuser surface flat 3. This second arrangement greatly facilitates the movement of the weft with respect to the diffuser surface 3 because it suppresses friction.

Figure 6 shows the object of this invention when the images on the diffuser screen are obtained by projection from the projectors 31 and 32, each of which projects one of the component images of a stereoscopic pair. Between the projection objectives and the translucent diffuser screen 3 there is a parallax barrier 2 consisting of opaque and transparent transparent bars, of a width approximately equal to half the width of the lenticle. Each of the projection objectives will generate through the barrier on the diffuser screen 3 an image strip per lens. It is easy to position the projectors so that for each cylindrical lens two strips of images are generated that occupy the entire width of the cylindrical lens. The precision adjustment between the barrier and the plot is easily achieved if the barrier is obtained by printing by adequately changing its scale. When the observer moves from left to right 921, 922 or vice versa it is easy to verify that the monitoring can be carried out by moving the barrier from right to left 201, 202 or vice versa. Similarly, when moving from back to front 911, 912 or vice versa, the parallax barrier should move from back to front 203, 204 or vice versa. It should be stressed that none of these movements of the parallax barrier produces blurring of the images in the lenticular frame since the optical power of the parallax barrier 2 is zero. If the method for monitoring the observer's head is that of Patent ES2004 / 000394, the head movement detector will consist of an optical system integral to the lenticular frame and a pair of photosensitive elements. in solidarity with the parallax barrier. Depending on the size of the pupils of the projection objectives and the situation of the barrier, it may be advisable in some cases to diaphragm these objectives as well as increase the size of the opaque bars with respect to the transparent ones.

Figure 7 shows in three dimensions the object of this invention shown in plan in Figure 6, the horizontal layout of the projectors 31 and 32 as well as the parallax barrier 2 with its opaque and transparent bars 211 and the retro projection screen 3 and the lenticular plot 1.

Figure 8 shows in plan a variant object of this invention when the images on the diffuser screen 3 are obtained by projection from two projection lenses located in the same vertical or by a single projector objective. The parallax barrier 2 is located between the projector and the projection screen 3. The observer tracking is from left to right 921, 922 and from front to back 911, 912 moving the barrier 2 in the directions 201, 202, 203 and 204. It should be stressed that none of these movements of the parallax barrier produces blurring of the images in the lenticular frame, as occurs in the devices described in Figures 2, 3 and 4 since the optical power of the frame is zero. If the method for monitoring the observer's head is that of Patent ES2004 / 000394, the movement detector of the head will be constituted by an optical system integral to the lenticular frame and a pair of photosensitive elements integral with the parallax barrier. .

Figure 9 shows in three dimensions the object of this invention shown in plan in Figure 8 with two objective projectors located in the same vertical. To each of these objectives 31, 32 polarized filters, linear 331 or circularly 332, or colored filters 333. are placed between the projection lenses 31, 32 and the translucent diffuser screen 3 is a parallax barrier 2 constituted by polarized filters or colored of a width approximately equal to half the width of the lenticle. The odd and even bars will be filters with perpendicular polarization directions 231 to each other when the filters of the projectors are linear polarizers, they will be levógiros and dextrógiros 232 filters when the projectors are polarized or red and blue 233 or (green) when the filters of The projectors are colored. It should be stressed that none of these movements of the parallax barrier produces blurring of the images in the lenticular frame, as occurs in the devices described in Figures 2, 3 and 4 since the optical power of the frame is zero. If the method for monitoring the observer's head is that of Patent ES2004 / 000394, the movement detector of the head will be constituted by an optical system integral to the lenticular frame and a pair of photosensitive elements integral with the parallax barrier. .

Figure 10 shows in three dimensions four variants of this invention represented in plan in Figure 8 in which the projection is made from a single projector lens 30. In this case the images corresponding to the right or left eye differ from each other by their polarization, by its color or by its situation. When the differentiation of the images by polarization is chosen, both the linear polarization 302 and the circular 301 can be used. When the linear polarization 302 is used, each of the images 11, 12 of the stereoscopic pair is polarized in a direction perpendicular to that of the Ia other. In this case, the parallax barrier 2 is constituted by linearly polarized bars 22 and in which the polarization directions of the odd and even bars are perpendicular to each other. With the use of circular polarization each image of the stereoscopic pair is polarized in a direction of rotation opposite to that of the other. In this case, the parallax barrier is constituted by circularly polarized bars, for example, levogyras for even and dextrogyran bars for odd ones 21. When the differentiation of the images by color 304 is chosen, each of the images is projected with a complementary color by example red R for one and blue, green or other color for another B. In this case the parallax barrier 24 It consists of colored bars, for example, red R for the pairs and blue B or green for the odd ones. When the discrimination of images by position 303 is chosen, each of the images of the stereoscopic pair occupies a different place, for example, the even horizontal strips for one image and the odd ones for the other. In this case, the parallax barrier consists of a mosaic of opaque and transparent rectangles 23. The width of each of these rectangles is approximately equal to half the width of the cylindrical lenticule and the height approximately equal to the height of the horizontal strips They contain the images. The rectangles are alternatively opaque and transparent in both the horizontal and vertical directions. The parallax barrier 2 is located between the projector lens and the flat diffuser screen 3. The frame will move from left to right or vice versa 201, 203 see figure 8 to follow the movement from right to left or vice versa of the observer 921, 922 and from front to back 203, 204 when the observer performs this movement 911, 912. If the method for monitoring the head of the observer is that of Patent ES2004 / 000394 the motion detector of the head will be constituted by a solidary optical system to the lenticular frame and by a pair of photosensitive elements integral to the parallax barrier. It is important to note that this movement of the barrier does not cause any blurring of the image with respect to the lenticular weave as explained in Figures 2, 3 and 4 that occurs in other systems.

Figure 11 shows in plan another variant of the object of this invention in which the monitoring of the movement from front to back of the observer is considered unnecessary because it is assumed that it does not leave the trapezium of orthoscopic vision limited by the distance z. The ways to differentiate the images are the same as those explained in Figure 10.

In this case, the different parallax barriers can be placed between the lenticular frame and the reproductive screen. The monitoring of the observer from left to right is done by producing a relative lateral movement of the frame with respect to the barrier or vice versa. If the observer places the midpoint between his eyes on the vertical line that passes through point 00 You can move from front to back without losing stereoscopic vision a distance z = D.0102 / P. 0102 being the distance between the eyes, D the distance from the observer to the lenticular frame and P the width of said frame. Whenever the observer makes movements from front to back traveling a distance less than this z value, it will maintain stereoscopic vision and the front-to-back monitoring of the observer can be avoided. If the method for monitoring the observer's head is that of Patent ES2004 / 000394, the movement detector of the head will be constituted by an optical system integral to the lenticular frame and a pair of photosensitive elements integral with the parallax barrier. .

Figure 12 shows in three dimensions the arrangement shown in plan in Figure 11. A single projector 30 projects the images 11 and 12 differentiated by circular polarization 301, linear 302, by situation 303 or by color 304. To each of these discriminations a different parallax barrier 21, 22, 23 or 24 corresponds. The explanation is the same as that given in Figure 10 with the difference of the barrier being located between the projection screen and the lenticular frame.

Figure 13 shows four vahantes object of this invention. The images are reproduced on an ordinary flat screen in color or specially designed for stereoscopic reproduction with polarization discrimination 4. The discrimination of images is made by linear polarization 42 or circular 41 by color 44 or by situation 43 on the reproductive surface. Each of these discriminations corresponds to a different parallax barrier 21, 22, 23 and 24. The observer is followed from left to right 921, 922 by producing a relative lateral movement of the frame with respect to the barrier 201, 202.

If the observer places the midpoint between his eyes on the vertical line that passes through point 00, he can move from front to back without losing the stereoscopic vision a distance z = D.0102 / P. Being 0102 Ia distance between the eyes, D the distance from the observer to the lenticular frame and P the width of said frame. Whenever the observer makes movements from front to back traveling a distance less than this z value, it will maintain stereoscopic vision and the front-to-back monitoring of the observer can be avoided. If the method for monitoring the observer's head is that of PCT Patent Number ES2004 / 000394, the motion detector of the head will be constituted by an optical system integral to the lenticular frame and by a pair of photosensitive elements integral to the barrier. Parallax

Claims

1. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction characterized by a first element consisting of a lenticular frame (1) capable of moving laterally from left to right with respect to a third element consisting of a flat diffuser surface (3, 4) where the two images constituting a stereoscopic pair and a second element constituted by a parallax barrier (2) composed of bars of a width approximately equal to half the width of the cylindrical lens component of the weft with capacity are reproduced of displacement in the transverse and longitudinal directions with respect to the third element constituted by the diffusing surface (3, 4).

2. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 1 wherein

The lenticular weave (1) has its face composed of cylindrical lenses (11) oriented towards the observer.

3. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 1 wherein the lenticular frame (1) has its flat face (12) oriented towards the observer.

4. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is composed of two projection lenses (31, 32) in which each projects the ordinary color image and unfiltered corresponding to each of the observer's eyes on a flat semi-transparent diffuser screen (3) and a parallax barrier (2) composed of opaque and transparent alternative bars (211, 212).

5. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claims 2 and 3 wherein the stereoscopic reproduction system is composed of two projector objectives (31, 32) in which each project the image in ordinary color and with a different polarization filter (331, 332) before each objective and in which each project the image corresponding to each of the eyes of the observer on a diffuser screen, flat and translucent (3) and a parallax barrier (2) in which each bar is a polarization filter corresponding to that of the even bars with the filter of a projector lens and that of the odd bars with the other's filter (232, 231).

6. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 5 wherein the filters are linear polarization (331) with polarization directions of the images perpendicular to each other.

7. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 5 in which the filters are circular polarized (332) being levógira for one eye or dextrógira for the other.

8. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is composed of two projection lenses (31, 32) in which each projects the image with a filter colored (333), red for one objective and green or blue for the other and in which each 'projects the image corresponding to each of the eyes of the observer on a diffuser screen, flat and translucent (3) and a parallax barrier (233) in which each bar is a colored filter corresponding to that of the even bars to the red R (blue or green) A and that of the odd ones to the blue or green (red).

9. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 6, 7 and 8 in which the parallax barrier with the possibility of longitudinal (203, 204) and transverse movement (201, 202) is located between the projection objectives and the translucent diffuser screen being able to follow the movements from left to right of the observer (921, 922) and from front to back (911, 912).

10. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 6, 7 and 8 in which the parallax barrier with the possibility of lateral movement (201, 202) is located between translucent diffusing screen and the lenticular weft being able to follow the movement from left to right of the observer (921, 922).

11. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is composed of a single objective (30) that projects the images corresponding to each one of the images in ordinary color. polarized observer eyes (301, 302) on a diffuser screen, flat and translucent (3) and a parallax barrier (2) in which each bar is a polarization filter corresponding to that of the even bars with the type of polarization corresponding to one of the images and that of the odd bars with that of the other.

12. Device for coupling to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 11 wherein the images are linearly polarized with polarization directions perpendicular to each other (302).

13. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 11 wherein the images are circularly polarized being levógira for one eye and dextrógira for the other (301).

14. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is composed of a single objective (30) that projects the images corresponding to each of the colors in ordinary color eyes of the observer in red (green or blue) for one eye and the complementary green or blue (red) (304) for the other on a diffuser screen, flat and translucent (3) and a parallax barrier (2) in which each bar is a colored filter, the even bars with the color corresponding to one of the images and the odd ones to that of the other (24).

15. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is composed of a single objective (30) through which images corresponding to ordinary images are projected. each of the eyes of the observer divided into horizontal strips, occupying the even strips the image of one eye and the odd ones of the other (303) on a flat and translucent screen (3) and a parallax barrier composed of a mosaic of opaque and transparent alternative bars (23) of a width approximately equal to half the width of the cylindrical lens component of the lenticular frame and of a height approximately equal to the height of the horizontal strips with which each image is projected being the horizontal strips even displaced with respect to the odd ones by the half-width of the bar.

16. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 11, 12, 13, 14 and 15 in which the parallax barrier (2) with the possibility of longitudinal (203, 204) and transverse movement (201 , 202) is located between the projection objectives and the diffuser screen, the movements can be followed from left to right (921, 922) and from front to back of the observer (911, 912).

17. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 11, 12, 13, 14 and 15 in which the parallax barrier (2) with the possibility of lateral movement (201, 202) is located between the screen diffuser and the lenticular plot being able to follow the movements from left to right of the observer (921, 922).

18. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is an ordinary screen for reproduction of two-dimensional images (4) in color in which the image of an eye it reproduces in red and the rest in blue, green or rest of colors after subtracting the red and between this screen and the lenticular weave a laterally movable parallax barrier (2) is placed (201, 202) in which each bar is a colored filter (24) the even bars with the color corresponding to one of the images and the odd ones to the color corresponding to that of the other.

19. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 wherein the stereoscopic reproduction system is an ordinary screen for reproduction of two-dimensional images (4) in which the image of an eye is reproduced in even horizontal strips and that of the other in odd horizontal strips and between this screen and the lenticular weave a laterally movable parallax barrier (23) (201, 202) composed of a mosaic of opaque and transparent alternative bars of a width approximately equal to half of the width of the cylindrical lens component of the lenticular weft and of a height approximately equal to the height of the horizontal strips with which each image is projected being the horizontal strips even of the odd ones by the half-width of the bar.

20. Device for coupling to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is a special screen for stereoscopic reproductions by linear polarization, between this screen (4) and the lenticular weft it locates a laterally movable parallax barrier (201, 202) composed of bars of a width approximately equal to half the width of the cylindrical lens component of the lenticular frame with the even bars polarized in a direction of polarization perpendicular to the odd ones.

21. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the stereoscopic reproduction system is a special screen for stereoscopic reproductions by circular polarization between this screen (4) and the lenticular frame is located a laterally movable parallax barrier (23) (201, 202) composed of bars of a width approximately equal to half the width of the cylindrical lens component of the lenticular weft being the polarized even bars in the direction dextrógiro and levógiro alternately.

22. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 18 and 19 in which the lenticular weave (11, 12) and the parallax barrier (2) without the possibility of movement between them remain together forming a single element.

23. Device for attaching to an ordinary two-dimensional player and achieving stereoscopic reproduction according to claim 2 and 3 in which the reproduction screen (3) is a flat surface with the printed images occupying even vertical strips for one image and odd for the other .