FR2643158A1 - Device for the projection of coloured images and/or the recording of images from coloured objects, especially in the fields of video, cinema and photography, and method of manufacturing the device - Google Patents

Abstract

The device consists of polyhedral elements assembled into a cubic solid, made of optically transparent material, some faces of which are provided with coatings having optical spectral-filtering or polarisation functions. The elements are arranged so as constitute interfaces transferring the light according to these filterings and/or these polarisations. The assembly is rigid and can perform the spectral selections in more than three mutually exclusive passbands, thus making it possible in particular to allow coloured stereoscopic images to be obtained under optimum conditions. The device can be combined with a single objective for projection as for recording.

Description

DEVICE FOR PROJECTING COLOR AND / OR IMAGES
THE RECORDING OF IMAGES FROM COLORED OBJECTS, IN PARTICULAR
IN THE FIELDS OF VIDEO, CINEMA, PHOTOGRAPHY, AND
METHOD FOR MANUFACTURING THE DEVICE.

 Most usually, the projection of color video images uses three image tubes, one corresponding to a spectral selection made at the time of shooting in the bandwidth of the primary red of the conventional three-color process, another in the primary green and the third in primary blue. The three images are projected on top of a screen to reconstruct an image in color. This projection is carried out either by three converging objectives, or by a single objective combined with two dichroic mirrors crossed at right angles.

 Devices with three objectives are complicated and expensive. Accurate overlaying of images requires difficult and unstable adjustments.

Cross mirror devices have several drawbacks. The crossing constitutes a "seam" more or less visible at the projection.

The whole is not very rigid and therefore adjustable. A fairly significant loss of yield is observed. In addition, it is practically excluded to use in this way more than two dichrolic mirrors, which limits the possibilities of this device.

 The present invention relates to a device intended in particular for the projection of video images which remedies these drawbacks and deficiencies.

This device can also be advantageously used for recording video images as well as for recording and projecting photographic and cinematographic images.

 According to the invention, in general, the device consists of polyhedral elements assembled into a cubic solid, of optically transparent material, some of the faces of which are provided with coatings having optical functions of spectral filtering or polarization. The elements are arranged so as to constitute interfaces transferring the light according to these filterings and / or these polarizations. The assembly is rigid and can perform spectral selections in more than three exclusive bandwidths from each other, which can in particular allow the obtaining of stereoscopic relief images and colors in optimal conditions. The device can be associated with a single objective both for projection and for recording.

 More specifically, the subject of the invention is a device for projecting color images and / or recording images from colored objects, characterized in that it comprises at least one body having its vertices inscribed in a cubic volume having at least three faces called "iconic faces" in the plane of which images must be formed, either emissive of light, or recordable, and a face called "optical conjugation face" associated, or with a projection objective , or for a shooting objective, said body consisting of at least two polyhedral elements of optically transparent material, each having at least one face provided with a coating intended to selectively transfer into a predetermined spectral band, and / or according to a predetermined polarization plane, the light relating to one of said images, these polyhedral elements being assembled in such a way that two coatings i dentics belonging to two faces of two different elements are located in the extension of one another in order to constitute together a single optical interface which must produce such a selective transfer, at least two of these interfaces which must constitute dichroic interference mirrors / filters crossed to ensure in exclusive spectral intervals of each other and according to all selected divisions of the visible spectrum said transfer between at least three iconic faces and the optical conjugation face.

According to other characteristics of the device according to the invention
- said polyhedral elements share said cubic volume in
four parts, constituting two interfaces crossed at right angles
each containing an edge of the optical conjugation face and
The diagonally opposite edge of the iconic face parallel to
this conjugation face.

- said polyhedral elements share said cubic volume in
eight parts, constituting three cross interfaces each containing
an edge of the optical conjugation face and the edge diagonally
opposite of the iconic face parallel to this face of conjugation.

- said polyhedral elements share said cubic volume in
sixteen parts, constituting four interfaces two to two crossed
at right angles each containing an edge of the conjugation face
optic and the diagonally opposite edge of the parallel iconic face
to this conjugation face.

- the faces or the parts of faces of the polyhedral elements which
are in contact are optically bonded together.

- at least one space not playing an active active optical role
between said body and said cubic volume, this space is lined
of an optically transparent material having advantageous faces
optically glued to the faces of the uolyhedral elements which
their adjacent Spells, so that the whole constitutes a volume
full cubic.

- the polyhedral elements are hollowed out on the side of the external faces
from the body.

- the device, intended for recording images from objects
colored, the optical conjugation face is associated with a lens
of shooting and the iconic faces are associated in their
respective shots at photosensitive image receptors, the whole
advantageously constituting an optical immersion system.

- the device intended for the projection of color images, the faces
iconic are associated in their respective plans with images
emissives such as slides, cinema films, or screen tiles
of video image tubes and the optical conjugation face is associated
to a projection objective, the assembly advantageously constituting
an optical immersion system.

- The device comprises at least two coatings constituting at
minus two optical interfaces to produce three transfers
selective in spectral bands extending respectively from
about 400 to 500 nanometers, 500 to 600 nanometers, 600 to 700 nanometers
very, corresponding to the selection of the classic three-color.

- the device being intended for shooting and / or projection
stereoscopic relief images interfaces relating to training
tion of the image intended for the left eye must produce trans
selective ferts in the spectral bands ranging from 400 to 500
nanometers and from 500 to 600 nanometers, and the interface or inter
faces, relating to the formation of the image intended for the right eye
must produce a selective transfer in the extended spectral band
from 600 to 700 nanometers, or vice versa between the line and
left.

- at least one of the optical interfaces that the device comprises
must produce a selective transfer in a bandwidth capable of
extend from 500 to 550 nanometers, from 550 to 600 nanometers, from
600 to 640 nanometers, from 640 to 700 nanometers.

- The device comprises at least three coatings constituting at
minus three optical interfaces to produce four transfers
selective in mutually exclusive spectral bands.

- the device has four coatings constituting four interfaces
optics to produce five selective transfers in bands
exclusive spectral of each other.

- the device, intended for taking pictures and / or projecting images
in stereoscopic relief, the interfaces relating to training
of 11 image intended for the left eye must produce transfers
selective in the spectral bands extending from 400 to 500 nanometers
and from 500 to 550 nanometers, and the interfaces relating to training
of the image intended for the right eye must produce transfers
selective in the spectral bands extending from 550 to 600 nanomè
very and from 600 to 700 nanometers, or vice versa between the line
and the left.

- the device intended for taking pictures and / or projecting images
in stereoscopic relief, the interfaces relating to training
of the image intended for the left eye must produce transfers
selective in the spectral bands extending from 400 to 500 nanometers
very, from 500 to 550 nanometers and from 640 to 700 nanometers, and the
interfaces relating to the formation of the image intended for the eye
right have to produce selective transfers in bands
spectral ranging from 550 to 600 nanometers and from 600 to 640 nano
meters, or vice versa between right and left.

- the device for taking stereosco relief images
spikes, the objective associated with the optical conjugation face of the body
has an optical system with mirrors or prisms in front allows
two simultaneous shots from two different points of view,
one assigned to the formation of the image intended for the left eye,
the other assigned to the formation of the image intended for the right eye.

- The device comprises at least two bodies, advantageously joined
two by two by one side.

- the images to be formed in the iconic faces are in
black and white.

 - at least one polyhedral element is removably mounted.

The invention also relates to a method of manufacturing the above device
We start by taking a cube of optically transparent material whose six faces are polished, that in a first operation we fragment it into two parts along a first plane passing through two diagonally opposite edges, one belonging to the optical conjugation face , The other with the opposite iconic face, that one polishes the diagonal faces resulting from this fragmentation into two parts, that one of these polished diagonal faces is provided with a treatment in thin layers constituting a dichroic mirror in a determined spectral interval, which we optically glue the two parts, reconstituting the cubic body, that in a second operation we fragment this cubic solid according to a second plane passing through two edges different from those concerned by the first operation, edges diagonally opposed between the optical conjugation face and the opposite iconic face, which, as during the first operation, the resulting diagonal faces are polished, they are provided with a dichroic treatment in another determined spectral interval, the two parts are optically glued, the initial cubic solid being divided into four glued parts and two interfaces then constituting two crossed dichroic mirrors, which we proceed, the if necessary, a third and then a fourth analogous operation, so that the cubic body is divided into eight parts glued with three interfaces constituting three crossed dichrolic mirrors and up to sixteen parts glued with four interfaces constituting four crossed dichroic mirrors.

 The invention will be better understood from the detailed description given below with reference to the attached drawing. Of course, the description and the drawing are given only by way of an indicative and nonlimiting example.

 In this drawing, FIG. 1 (single figure) geometrically represents the diagram of a body according to the invention.

This body is a solid made of an optically transparent material in the visible spectrum. Its vertices m, n, p, q, r, s, t, u, are inscribed in a cubic volume. The body can be a cube, or even have recesses, its vertices being inscribed in a cube. The cubic volume has six faces, A, B, C, D, E, F. At least three and at most five of these faces are called "iconic faces" because images must be formed in their plane, whether in view of projecting color images or recording images from colored objects. In the figure, the iconic faces are A, B, C, D, E. The sixth face, for example
F is said to be "optical conjugation face" because it is intended to be associated with a projection or shooting optic.

 In the case of a device intended for projection, images emitting light must be formed in the planes of at least three iconic faces, for example A, B, E and, where appropriate, also in the planes of the two other iconic faces, C, D.

 For example, in the case of a projection of color video images, according to the conventional three-color process, a primary red video image (600 to 700 nanometers) is formed in side A. This may be the image provided by the screen panel arranged substantially in the plane of side A of a video image tube, image having been selected in the band of primary red during the shooting. This image can itself be emissive in primary red, or in a spectral band wider than 600 - 700 nanometers, or in white light. In side B is formed a video image having been selected when shooting in the band, for example, primary blue (400 to 500 nanometers), emissive image in primary blue, in blue-green in a wider band or In white light, on the E side, a video image selected at the time of shooting in the primary green band (500 to 600 nanometers) is formed, an emissive image in primary green, in broadband green or in white light.

 The body 1, itself constituting a complete cube in the example shown in the drawing, is made up of four polyhedral elements: ijmnpq, ijrstu, ijpqut, ijmnsr (i denoting the intersection of the diagonals mu and rq of the side C, and j designating the intersection of the diagonals nt and sp of the face D). These polyhedral elements share the cubic volume in four parts constituting two interfaces, m n u t and r s q p, crossing at right angles according to the line segment i j. The plane m n u t contains the edge u t of the face F of optical conjugation and the edge m n diagonally opposite of the iconic face E parallel to this face of conjugation. The rsqp plane contains the edge qp of the face F of optical conjugation and the rs diagonally opposite edge of the iconic face E. The mnut interface is provided with a dichroic interference mirror - obtained according to the manufacturing process described above after - reflecting primary red light and transmitting blue and green, that is to say cyan light, complementary to red. The r s q p interface is equipped with a dichroic interference mirror reflecting primary blue light and transmitting green and red, that is to say yellow light, complementary to blue.

 Under these conditions, from the emissive image formed in the plane of side A, the dichroic mirror mnut, inclined at 450 with respect to this side A, gives a virtual image in primary red in the plane of side E. From l emissive image formed in the plane of side B, the rsqp dichroic mirror gives a virtual image in primary blue in the plane of side E. The projection objective (not shown) associated with the optical conjugation face, F, captures the primary red light relative to the red image virtually localized in side E and the primary blue light relating to the blue image virtually localized in side E.

The projection objective also captures the light emitted by the image, this time real, formed in the E side. This last light reaches the objective after having crossed the two dichrolic mirrors. Only its component in the primary green achieves the objective.

We understand that the images formed in the iconic faces A, B,
E, can be emissive in wide bands or even in white light, since it is the dichroic mirrors which operate the strict trichrome selection.

 The emissive images, one real, the other virtual, are superimposed very precisely on the E side and the lens projects a reconstituted three-color image on a screen.

The advantages of the device are obvious. It is rigid, its chronic mirrors are seamlessly detectable, they escape vibration, dust. The settings are fine and foolproof. The screen tiles of the video image tubes, as well as the projection lens, can be mounted in optical contact with the faces of the body with which they are associated.

The assembly then constitutes an optical immersion system, the luminance obtained at projection then benefiting from a gain equal to the square of the refractive index of the optical media in immersion, that is to say a gain factor of 2.25 for the glass.

 The emissive images can also be slides or images of cinematographic films, each illuminated by a source associated with a condenser. They can advantageously be in black and white, having been spectrally selected when shooting according to the three-color process.

 In the case of a device according to the invention intended for taking a picture, the optical process works in reverse. From colored objects, the shooting objective, associated with side F, forms in the planes of sides A, B, E, real images. respectively selected spectrally according to the primary red, blue and green. These images can advantageously be recorded in black and white by photosensitive receivers, whether in the fields of photography, cinema or video. The interest of a black and white recording for the photo or the cinema is to obtain documents almost indestructible in time.

We can then at any time reconstruct color images using the same device in reverse.

 Another important advantage of the device according to the invention is to allow spectral selection in more than three spectral intervals.

In four intervals and up to five intervals, of course strictly exclusive of each other.

 It is enough to use the five iconic faces, A, B, C, D, E. To the faces C and D correspond two interfaces, respectively n q u s and m p t r.

 In the case where four iconic faces are used, for example A, B, C, E, the body is divided into eight polyhedral parts, as will be better understood from the description below of the process for manufacturing the device. . Three interfaces are formed: m n u t, r s q p, m p t r. The latter is provided with a dichroic interference mirror giving an emissive image formed in the plane of face C a virtual image in the plane of face E. Under these conditions, the spectral analysis is performed according to four exclusive intervals others, according to all desired divisions of the visible spectrum.

 An interesting example of application is that of an image recording intended for stereoscopic observation in color. It is, of course, possible to use the device described above using two crossed dichroic mirrors producing three selective transfers in the spectral bands of the conventional three-color process. We then assign to the images intended for the left eye the selective transfers in the blue (400 to 500 nanometers) and green bands (500 to 600 nanometers) and to the image intended for the right eye the selective transfer in the red band (600 to 700 nanometers).

Or vice versa between the right and the left. We endow the shooting objective associated with the optical conjugation face of the body with an optical system with mirrors or prisms of any known type. It is thus possible to operate simultaneously two shots with a spacing of the predetermined optical axes for the desired stereoscopic effect. One of these shots is for the left eye, the other for the right eye. At the final observation, the left eye is provided with a cyan filter (400 to 600 nanometers) and the right eye is provided with a red filter (600 to 700 nanometers). Preferably dichrolic filters. Or vice versa between the right and the left, in correspondence with the choice adopted at the shooting. A stereoscopic color observation is certainly obtained in this way. However, the observer feels visual discomfort due to the disproportion between the spectral width of the cyan band, assigned to one of his eyes and the spectral width of the band. red assigned to his other eye. The color rendering also leaves something to be desired.

 The device according to the invention allows much better solutions.

 In the case which has just been described, where four iconic faces and three crossed interfaces are used, it is possible to assign to the images intended for the left eye these selective transfers in the bands 400 to 500 nanometers and 500 to 550 nanometers, and to the right eye selective transfers in the bands 550 to 600 nanometers and 600 to 700 nanometers.

Or vice versa between the right and the left. We endow the lens of shooting of a system with mirrors or prisms as it was said. On observation, the left eye is provided with a filter, preferably dichrolic, in the pass band 400 to 550 nanometers and the right eye is provided with a filter in the pass band 550 to 700 nanometers. In this way, the visible spectrum is divided into two bands of equivalent width, well balanced around the wavelength of 550 nanometers which is at the top of the visual efficiency curve. This results in great visual comfort and a finer rendering of the colors. In prolection, we use a simple objective.

 In the case where five iconic faces and four cross interfaces are implemented, an additional refinement can be added.

You can assign selective transfers in the bands 400 to 500 nanometers, 500 to 550 nanometers, 640 to 700 nanometers to the left eye, and selective transfers in the bands of 550 to the right eye. at 600 nanometers and from 600 to 640 nanometers. An almost perfect balance is thus obtained between the light energies received by each of the eyes. This data was brought to light by the work of physiological optics by Louis Lumière in 1935, and the device according to the invention allows its concretization.

 Obviously, the implementation of five iconic faces and five selective transfers can be used according to any division of the visible spectrum and for all operations requiring a plurality of selective transfers that the state of the art did not previously allow.

 The device according to the invention can associate several bodies. These bodies can be separated or joined two by two by a face, which can be advantageous. The possibilities offered by such associations are increased. For example, two cubic bodies according to the invention, joined by one face, offer eight iconic faces and up to eight selective transfers. Two shooting or projection objectives are associated with the two optical conjugation faces offered by these bodies.

 Polarizing filters can be added to a body of the device, both in the iconic face planes and in the plane of the optical conjugation face. They can also be added to dichrolic treatments or replace them in the interface plans. It is thus possible to combine the possibilities already described of the device with all known implementations of polarizing filters, in particular in the field of projection of stereoscopic relief images.

 The present invention also relates to a method of manufacturing the device. We start from a cubic solid made of optically transparent material throughout the visible spectrum, for example glass, and whose six faces are polished. In a first operation (see the figure in the drawing), we split this cubic solid into two parts, for example by sawing it, according to a first plane such as mntu, plane passing through two diagonally opposite edges of the cube, one of which belongs to the side F of optical conjugation, the other mn which belongs to the iconic side E opposite.

The two diagonal faces are polished resulting from this fragmentation into two parts. One of these diagonal faces is provided with a treatment in thin layers constituting a dichrolic mirror in a determined spectral interval.

For example, from 600 to 700 nanometers, in primary red. This treatment is carried out rather on the diagonal face belonging to the mntuqp fragment, that is to say on the side of the iconic face mnpq (face A) where the image selected in red will be located. The two fragments are then optically bonded, using an adhesive having the same refractive index as that of the cubic solid. In a second operation, the reconstituted solid is fragmented according to a second plane such as rspq, plane passing through two edges different from those concerned by the first operation
The resulting diagonal faces are polished. The rspq side belonging to the rspqtu fragment is provided with a treatment constituting a dichroic mirror in the spectral band of 400 to 500 nanometers, that of primary blue, for example. This fragment is on the side of the iconic rstu side (side B ) where will be the selected image in blue. The two fragments are optically glued. One thus reconstitutes a cubic solid comprising four polyhedral parts. By calling ij the intersection of the two diagonal planes mntu and rspq, the four parts are: ijmnpq, ijrstu, ijqptu, ijmns r. The dichrolic treatments were applied to the faces of the parts ijmnpq, ijrstu, ijqpt u. These parts constitute active polyhedral elements of the body. The ijmnsr part is a polyhedral fragment having no face constituting a dichroic mirror. We can stick to this stage of the manufacturing process when we only need two interfaces constituting dichrolic mirrors and able to ensure three transfers selective.

 If we want to have more than two dichroic mirrors and more than three selective transfers, we continue the manufacturing process.

We again fragment the reconstituted cube according to a third diagonal plane such that n q u s. The resulting diagonal faces are polished. We provide the nqus face belonging to the nquspt polvèdre located on the side of the iconic face D, with a third kind of treatment constituting a dichroic mirror in a third determined spectral band, the face D being the iconic face in the plane of which must find an image having been selected in this determined spectral band. The two fragments are optically glued. The cubic solid thus reconstituted comprises eight polyhedral parts. It includes three dichrolic mirrors and allows four selective transfers.

We can finally fragment this solid reconstituted according to a fourth diagonal plane, mpt r. The resulting diagonal faces are polished. We provide the face mptr belonging to the polyhedron mptrqu located on the side of the iconic face C, with a fourth kind of treatment constituting a dichroic mirror in a fourth determined spectral band, the face
C being the iconic face in the plane of which must be an image having been selected in this fourth spectral band. The two fragments are optically glued. The solid thus reconstituted comprises sixteen polyhedral parts. All have a common vertex which is the center O of the cubic solid, at the intersection of four diagonals, mt, nu, rp, sq, and two medians, ij and k h. It includes four dichroic mirrors and allows five selective transfers.

Claims (19)

1) Device for projecting color images and / or recording images from colored objects, characterized in that it comprises at least one body having its vertices inscribed in a cubic volume having at least three faces called "iconic faces" in the plane of which images, either light-emitting or recordable, must be formed, and a face called "optical conjugation face" associated either with a projection lens or with a shooting lens seen, said body consisting of at least two polyhedral elements of optically transparent material, each having at least one face provided with a coating intended to selectively transfer into a predetermined spectral band, and / or according to a predetermined polarization plane, the light relating to one of said images, these polyhedral elements being assembled in such a way that two identical coatings belonging to two faces of two elements different elements are located in the extension of one another in order to constitute together a single optical interface having to produce such a selective transfer, at least two of these interfaces having to constitute mirrors / cross dichrolic interference filters having to ensure in spectral intervals exclusive of each other and according to all selected divisions of the visible spectrum, said transfer between at least three iconic faces and the optical conjugation face. 2) Device according to claim 1, characterized in that said polyhedral elements share said cubic volume in four parts, constituting two crossed interfaces at right angles each containing an edge of the optical conjugation face and one diagonally opposite edge of the iconic face parallel to this conjugation face. 3) Device according to claim 1, characterized in that said polyhedral elements share said cubic volume in eight parts, constituting three crossed interfaces each containing an edge of the optical conjugation face and the diagonally opposite edge of the iconic face parallel to this conjugation face. 4) Device according to claim 1, characterized in that said polyhedral elements share said cubic volume in sixteen parts, constituting four interfaces two to two crossed at right angles each containing an edge of the optical conjugation face and the diagonally opposite edge of the iconic side parallel to this conjugation side. 5) Device according to claim 1, characterized in that the faces or the parts of faces of the polyhedral elements which are in contact are optically bonded together. 6) Device according to claim t, characterized in that, at least one space not playing an active optical role remaining between said body and said cubic volume, this space is lined with an optically transparent material having faces advantageously bonded optically to faces of the polyhedral elements which are adjacent to them, so that the whole constitutes a complete cubic volume. 7) Device according to claim 1, characterized in that the polyhedral elements are hollowed out on the side of the external faces of the body.  8) Device according to claim 1, characterized in that, intended for recording images from colored objects, the optical conjugation face is associated with a shooting objective and the iconic faces are associated in their respective planes to photosensitive image receptors, the assembly advantageously constituting an optical immersion system. 9) Device according to claim 1, characterized in that, intended for the projection of color images, the iconic faces are associated in their respective planes with emissive images such as slides, cinema films, or screen slabs of tubes video image and the optical conjugation face is associated with a projection objective, the assembly advantageously constituting an optical immersion system. 10) Device according to claim 1, characterized in that it comprises at least two coatings constituting at least two optical interfaces having to produce three selective transfers in spectral bands extending respectively from about 400 to 500 nanometers, 500 to 600 nanometers , 600 to 700 nanometers, corresponding to the selection of the conventional three-color process. 11) Device according to claim 1, characterized in that, intended for shooting and / or projection of stereoscopic relief images, the interfaces relating to the formation of the image intended for the left eye must produce selective transfers in the spectral bands extending from 400 to 500 nanometers and from 500 to 600 nanometers, and the interface or interfaces, relating to the formation of the image intended for the right eye must produce a selective transfer in the spectral band extending from 600 to 700 nanometers, or vice versa between the right and the left. 12) Device according to claim 1, characterized in that at least one of the optical interfaces which it comprises must produce a selective transfer in a bandwidth which may extend from 500 to 550 nanometers, from 550 to 600 nanometers, from 600 at 640 nanometers, from 640 to 700 nanometers. 13) Device according to claim 1, characterized in that it comprises at least three coatings constituting at least three optical interfaces having to produce four selective transfers in exclusive spectral bands from each other and according to all selected divisions of the visible spectrum. 14) Device according to claim 1, characterized in that it comprises four coatings constituting four optical interfaces to produce five selective transfers in exclusive spectral bands from each other and according to all selected divisions of the visible spectrum. 15) Device according to claim 1, characterized in that, intended for shooting and / or projection of stereoscopic relief images, the interfaces relating to the formation of the image intended for the left eye must produce selective transfers in the spectral bands extending from 400 to 500 nanometers and from 500 to 550 nanometers, and the interfaces relating to the formation of the image intended for the right eye must produce selective transfers in the spectral bands extending from 550 to 600 nanometers and from 600 to 700 nanometers, or vice versa between the right and the left.  t6) Device according to claim 1, characterized in that, intended for the taking and / or projection of stereoscopic relief images, the interfaces relating to the formation of the image intended for the left eye must produce selective transfers in the spectral bands extending from 400 to 500 nanometers, from 500 to 550 nanometers and from 640 to 700 nanometers, and the interfaces relating to the formation of the image intended for the right eye must produce selective transfers in the spectral bands extending from 550 to 600 nanometers and from 600 to 640 nanometers, or vice versa between the right and the left. 17) Device according to claim 1, characterized in that, intended for taking pictures of stereoscopic relief images, the objective associated with the optical conjugation face of the body is provided with an optical system with mirrors or prisms of any known type intended to allow two simultaneous shots from two different points of view, one assigned to the formation of the image intended for the left eye, the other assigned to the formation of the image intended for the 'right eye. 18) Device according to claim 1, characterized in that it comprises at least two bodies, advantageously joined two by two by a face. 19) Device according to claim 1, characterized in that the images to be formed in the iconic faces are in black and white. 20) Device according to claim 1, characterized in that at least one polyhedral element is removably mounted. 21) A method of manufacturing a device according to claim 1, characterized in that one begins by taking a cube of optically transparent material whose six faces are polished1 that in a first operation it is divided into two parts according to a first plane passing through two diagonally opposite edges, one belonging to the optical conjugation face, the other to the opposite iconic face, which one polishes the diagonal faces resulting from this fragmentation into two parts, which one provides of these polished diagonal faces of a treatment in thin layers constituting -a dichrolic mirror in a determined spectral interval, which one optically glues the two parts, reconstituting the cubic body, that in a second operation one fragments this cubic solid according to second plane passing through two edges different from those concerned by the first operation, edges diagonally opposite between the optical conjugation face and the iconic face o opposite, that, as during the first operation, the resulting diagonal surfaces are polished, they are provided with a dichrolic treatment in another determined spectral interval, the two parts are optically glued, the initial cubic solid being divided into four parts glued and two interfaces then constituting two crossed dichrolic mirrors, which is carried out, if necessary, a third and then a fourth analogous operation, so that the cubic body is divided into eight parts glued with three interfaces constituting three mirrors crossed dichroics and up to sixteen parts glued with four interfaces constituting four crossed dichr & ques mirrors.