MULTI-SPECTRAL HARMONIZATION DEVICE INTENDED TO ALIGN

THE OPTICAL CHANNELS OF AN OPTRONIC SYSTEM

TECHNICAL AREA

The present invention relates to devices for harmonizing optical channels in different spectral bands for use in tuning optronic systems and multispectral detectors.

STATE OF THE PRIOR ART

An optronic system consists of several detection devices such as sensors, sights or imagers, each of these detection devices operating in a spectral band which is specific to it. For an optronic system to be efficient, it is necessary to precisely align the optical channels of these different detection devices with respect to each other. The adjustment of an optronic system consists in harmonizing its different optical channels, in other words in adjusting their angular orientation and controlling their parallelism.

An optronic system harmonization device usually comprises several optical beams, each of these beams emitting at a specific wavelength. These different beams are precisely oriented with respect to each other thanks to optical metrology systems mounted on test benches.

The harmonization of the different channels of an optronic system must be carried out periodically because the alignment of optical channels of such a system has a limited stability over time which is generally shorter than the lifetime of the optronic system.

A problem posed for the harmonization of optronic systems relates to maintenance operations in field environments, for example when one of the detection devices of the optronic system must be changed. The harmonization devices usually used have alignment constraints which cannot be fulfilled in non-standardized environments such as field conditions.

Certain less constrained harmonization devices rely on the spectral overlap of different detectors. This makes it possible, from the same optical beam, detectable in the spectral bands of several devices, to control the orientation of the channels of these devices. However, this device does not make it possible to simultaneously adjust several optical channels in distant spectral bands except in certain special cases and at the cost of degrading the performance of the devices.

It is desirable to provide a solution which simplifies the harmonization of the optical channels of an optronic system in different spectral bands and in particular in non-standardized environments. In particular, it is desirable to provide a solution which is usable in the field and which is easy to use while maintaining sufficient precision for the performance of optronic systems.

It is also desirable to provide a solution making it possible to simultaneously adjust all the optical channels of an optronic system.

It is also desirable to provide a solution that is easy to implement and at low cost.

DISCLOSURE OF THE INVENTION

The invention relates to a device for multispectral harmonization of optronic systems comprising a multispectral collimated beam for the alignment of several optical channels.

An object of the present invention is to provide a multispectral harmonization device intended to align the optical channels of an optronic system. The multispectral harmonization device comprises at least two directional optical sources emitting respective optical beams of different wavelengths belonging to different spectral bands. The harmonization device further comprises a parabolic mirror and means for positioning and orienting each of the optical sources so that each of the optical beams emitted by said optical sources passes through the optical focus of the parabolic mirror before being reflected by said parabolic mirror so that all the optical beams form by reflection on the parabolic mirror a multispectral collimated beam.

Thus, it is possible to simultaneously adjust several optical channels of an optronic system in different spectral bands with a multi-spectral collimated beam.

According to a particular embodiment of the invention, the positioning and orientation means further comprise an alignment mask consisting of an opaque wall and comprising a hole. The alignment mask is placed in a plane orthogonal to the optical axis of the parabolic mirror such that the location of the hole matches the optical focus of the parabolic mirror.

Thus, the location of the optical focus of the parabolic mirror is materialized by a hole, which makes it possible to easily align an optical beam with the optical focus of the parabolic mirror by passing said optical beam through the hole.

According to a particular embodiment of the invention, the hole is centered on the alignment mask and the dimension of the opaque wall is at least ten times greater than the dimension of said hole.

Thus, the alignment mask makes it possible to intercept the incident optical beams which do not pass through the hole of the alignment mask and are therefore not aligned with the optical focus of the parabolic mirror, which facilitates the alignment of the optical beams. with the optical focus of the parabolic mirror and therefore the adjustment of the position and orientation of the sources emitting said optical beams.

According to a particular embodiment of the invention, fixing means removably assemble the alignment mask and the parabolic mirror. Thus, it is possible to use the alignment mask only during positioning and orientation operations of the light sources.

According to a particular embodiment of the invention, fixing means assemble the alignment mask and the parabolic mirror in a permanent manner and the external dimensions of the opaque wall are between 10 and 30% of the dimensions of the parabolic mirror.

Thus, it is possible to maintain the position of the alignment mask relative to the optical focus of the parabolic mirror at all times, allowing the use of the multispectral collimated beam at any time.

According to a particular embodiment of the invention, the face of the opaque wall oriented towards the optical sources is non-reflecting.

Thus, the optical beams which do not pass through the hole of the alignment mask do not generate parasitic optical beams by reflection on said alignment mask.

According to a particular embodiment of the invention, the fixing means are adjustable.

Thus, it is possible to adjust the position of the hole relative to the optical focus of the parabolic mirror.

According to a particular embodiment of the invention, the parabolic mirror is divided into a number of sectors equal to the number of channels of an optronic system to be harmonized, each of said sectors corresponds to a spectral band and each of the sectors is illuminated by at at least one optical beam originating from at least one optical source of emission wavelength belonging to the spectral band of the corresponding sector. Thus, to each optical channel of an optronic system corresponds a sector of the parabolic mirror in a specific spectral band.

The invention also relates to a positioning system comprising a multispectral harmonization device for which the positioning and orientation means further comprise optical detection means. Each optical detection means is sensitive to the emission wavelength of an optical source to be positioned and oriented. The positioning system is such that each optical detection means detects an optical signal at the emission wavelength of the optical source if the optical beam emitted by said optical source passes through the hole of the alignment mask and does not detect no optical signal at the emission wavelength of the optical source if the optical beam emitted by said optical source does not pass through the hole in the alignment mask.

Thus, the positioning system makes it possible to easily implement a multispectral collimated beam.

The invention also relates to a method for positioning and orienting at least two optical sources of a multispectral harmonization device, said sources emitting respective optical beams of different wavelengths belonging to different spectral bands. The positioning and orientation method comprises for each of the optical sources the following steps:

installation of an optical detector sensitive to the emission wavelength of said optical source to be positioned and oriented; adjustment of the position and orientation of the optical source so that the optical beam emitted by said source is directed towards the parabolic mirror and passes through a hole drilled in an alignment mask, the hole being located at the focus of said parabolic mirror; detection, by the optical detector sensitive to the emission wavelength of the source, of an optical signal at said emission wavelength of the source, characteristic of the optical beam coming from said source which has passed through the hole, and generation of information representative of the detection.

Thus, the positioning and orientation method makes it possible to easily obtain a multispectral collimated beam.

According to a particular embodiment of the invention, the positioning and orientation method further comprises a step of installing the alignment mask so that the hole of said alignment mask is located at the focus of the parabolic mirror.

Thus, the hole of the alignment mask materializes the optical focus of the parabolic mirror.

According to a particular embodiment of the invention, the positioning and orientation method further comprises a step consisting in removing the optical detector sensitive to the emission wavelength of the source when the position and orientation of said optical source are validated.

Thus, the position and orientation of each source are adjusted with an optical detector adapted to the emission wavelength of the source and an optical detector cannot prevent the detection, by another optical detector, of an optical beam.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics of the invention mentioned above, as well as others, will emerge more clearly on reading the following description of an exemplary embodiment, said description being given in relation to the accompanying drawings, among which:

[Fig. 1] schematically illustrates a multispectral harmonization device comprising a multispectral collimated beam;

[Fig. 2A] schematically illustrates a front view of the multispectral harmonization device comprising a multispectral collimated beam;

[Fig. 2B] schematically illustrates a front view of the multispectral harmonization device with the division into several sectors of the parabolic mirror;

[Fig. 3] schematically illustrates a first positioning system for implementing the multispectral harmonization device;

[Fig. 4] schematically illustrates a second positioning system for implementing the multispectral harmonization device;

[Fig. 5] schematically illustrates a method for positioning and orienting the sources for the implementation of the multispectral harmonization device.

DETAILED EXPOSURE OF EMBODIMENTS

The present invention consists of a device for harmonizing optronic systems comprising a multispectral collimated beam.

Fig. 1 schematically illustrates a harmonization device comprising a multispectral collimated beam.

Le dispositif d’harmonisation de systèmes optroniques comporte un miroir parabolique 10 sur lequel viennent se réfléchir des faisceaux optiques incidents 131, 132, 133, 134 issus respectivement de sources 121, 122, 123 et 124. Lesdites sources 121 à 124 sont des sources lumineuses qui émettent des faisceaux optiques directionnels, spatialement et temporellement cohérents, comme par exemple des diodes laser. Les faisceaux optiques incidents 131, 132, 133 et 134 respectivement émis par les sources 121, 122, 123 et 124 sont de différentes longueurs d’onde. Des faisceaux optiques réfléchis 141, 142, 143 et 144 résultent respectivement de la réflexion des faisceaux optiques incidents 131, 132, 133 et 134 sur le miroir parabolique 10. Le dispositif d’harmonisation comporte également des moyens de positionnement et d’orientation permettant de positionner et d’orienter les sources 121 à 124 de telle sorte que les faisceaux optiques incidents 131 à 134 sont émis vers le miroir parabolique 10 dans une direction de propagation qui passe par le foyer optique 11 dudit miroir parabolique 10. La direction de propagation des faisceaux optiques réfléchis 141 à 144 est par conséquent parallèle à l’axe optique 17 du miroir parabolique 10. Les faisceaux optiques réfléchis 141 à 144 sont ainsi parallèles entre eux. En d’autres termes, un faisceau 18 constitué de l’ensemble de ces faisceaux optiques réfléchis 141 à 144 est collimaté.

In addition, the reflected optical beams 141, 142, 143 and 144, resulting from the reflection on the parabolic mirror 10 of the incident optical beams 131, 132, 133 and 134

respective, have different wavelengths which correspond respectively to those emitted by the sources 121, 122, 123 and 124. The different wavelengths can relate to different bands of the electromagnetic spectrum, for example visible spectral bands and infrared. The beam 18 consisting of all of the reflected optical beams 141 to 144 is called a multispectral beam.

The sources 121 to 124 are positioned and oriented by the positioning and orientation means in such a way that each of the incident beams 131 to 134 is directed towards the parabolic mirror 10, in a space limited by the opening of said parabolic mirror 10. In addition, the positioning and orientation means make it possible to position said sources 121 to 124 outside the field of the parabolic mirror 10 outside the diameter of said parabolic mirror 10. In other words, the sources are located at the center. outside the zone where the reflected optical beams 141 to 144 propagate so that said reflected optical beams 141 to 144 are not intercepted by one of the sources 121 to 124.

The positioning and orientation means may comprise an alignment mask 15. The alignment mask 15 comprises a preferably opaque wall and a hole, for example disposed in its center, is arranged so that the hole of the mask of alignment either to the optical focus 11 of the parabolic mirror 10. The hole in the alignment mask 15 materializes the location of the optical focus 11. The positioning and orientation means make it possible to position and orient the sources 121 to 124 in such a way that the optical beam emitted by each source passes through the hole in the alignment mask 15, therefore through the optical focus 11 of the parabolic mirror 10. The alignment mask 15 is preferably placed in a plane orthogonal to the optical axis 17 of the parabolic mirror 10.

The diameter of the hole of the alignment mask 15 is variable according to the alignment precision sought for the adjustment of the optical channels of an optronic system. The divergence of the reflected optical beams 141 to 144 after the incident optical beams 131 to 134 have passed through the hole of the alignment mask depends on the apparent opening of the hole and therefore on the size of the hole as well as the focal length of the mirror. parabolic 10. The divergence of the beams or angular dispersion must be low compared to the desired precision on the angular orientation. For example, for holes of width 1% and 0.1% of the distance between the optical focus and the center of the parabolic mirror, the divergence at 90% of the energy is respectively +/- 0.31 ° (i.e. 5 , 4 mrad) and +/- 0.031 0 (ie 0.55 mrad), which makes it possible to perform an alignment of the optical channels of an optronic system with angular accuracies of the order of 1 ° and 0.1 ° respectively.

The function of the alignment mask 15 is to intercept at least part of the incident optical beams which are not oriented to pass through the hole of the alignment mask 15, in order to facilitate the positioning and positioning operation. orientation of the sources 121 to 124 and therefore the implementation of the multispectral harmonization device. For this, the wall of the alignment mask 15 has a surface dimension at least ten times greater than that of the hole.

The alignment mask 15 may be removable. It is in this case installed at the optical focus 11 of the parabolic mirror 10 during the positioning and orientation operations of the sources 121 to 124 and then removed when using the multi-spectral collimated beam 18 for the adjustment of optical channels of an optronic system. The external dimensions of the alignment mask 15 can in this case reach the dimensions of the parabolic mirror 10, which makes it possible to facilitate the operation of positioning and orienting the sources 121 to 124 and in particular the alignment of the incident optical beams. 131 to 134 emitted by said sources 121 to 124 with the optical focus 11 of the parabolic mirror 10 and a point of the parabolic mirror 10. Furthermore, when said removable alignment mask 15 is removed,

The alignment mask can also be permanently attached to the mirror which makes it possible to locate the optical focus 11 of said parabolic mirror 10 at any time. The positioning and orientation of the sources so that the incident optical beams 131 to 134 pass through the hole of the alignment mask 15 can thus be carried out easily, without resorting to other adjustment means. The permanent attachment of the alignment mask 15 to the parabolic mirror 10 allows the optronic harmonization device of the present invention to be easily transported and used in different environments. In this case, the outer dimensions of the alignment mask 15 are small enough that the reflected optical beams 141 to 144 are not intercepted by the alignment mask 15. For example,

preferably non-reflective so as to avoid parasitic reflections in uncontrolled directions of propagation.

Fig. 2A shows a front view of the multispectral harmonization device comprising a multispectral collimated beam. The sources 121, 122, 123 and 124, emitting at different wavelengths, are located outside the field of the parabolic mirror 10 outside the diameter of said parabolic mirror 10 and emit an optical signal towards said parabolic mirror 10 in the form incident optical beams 131 to 134 whose direction of propagation passes through the optical focus 11 of said parabolic mirror 10, said optical focus 11 being materialized by the central hole of the alignment mask 15. The incident optical beams 131 to 134 are then reflected by said parabolic mirror 10 generating reflected optical beams 141 to 144 parallel to each other.

The alignment mask 15 can be fixed to the parabolic mirror 10 by means of clips 20. Said fixing clips 20 are preferably adjustable in order to be able to adjust the position of the hole with respect to the optical focus 11 of the parabolic mirror 10.

Fig. 2B schematically illustrates a front view of the multispectral harmonization device divided into several sectors. The parabolic mirror 10 is divided into a number of sectors 201 to 204 defined by the number of optical channels of an optronic system to be harmonized. On each of these sectors 201 to 204 is reflected one or more incident optical beams whose wavelength or wavelengths belong to the same range of wavelengths characteristic of the spectral band of one of the optical channels of an optronic system. . Thus, each sector corresponds to the emission of one or more optical beams reflected in a spectral band. In the example of FIG. 2b, the reflected optical beam 141 of emission wavelength from the source 121 is reflected on the sector 201, as are the reflected optical beams 142,

In the example of Figs. 1, Fig. 2A and Fig. 2B, four sources generating four incident optical beams and therefore four reflected optical beams are shown. A more or less large number of sources and therefore of incident and reflected optical beams can obviously be used by the present invention.

Fig. 3 illustrates a sectional view of a first positioning system for implementing the multispectral harmonization device.

The implementation of the multispectral collimated beam 18 by the multispectral harmonization device of the present invention involves the positioning and orientation of the sources 121 to 124 such that the optical beams emitted by said sources pass through the optical focus 11 of the parabolic mirror 10 and makes it possible to control the parallelism of the optical beams 141 to 144.

The positioning system comprises a detector 16 making it possible to check the position and orientation of a source 121 and the passage of an incident optical beam 131 through the optical focus 11 of the parabolic mirror 10. The detector 16 sensitive to the length d The wave emitted by the source 121, for example a flux detector, is placed between the alignment mask 15 and the parabolic mirror 10 so as to be able to detect any incident optical beam which passes through the alignment mask 15 passing through the hole.The detector 16 has a detection surface of smaller dimension than that of the alignment mask 15 in order to detect only the optical signals passing through the hole and thus to avoid detecting optical signals coming from a source and which would be emitted in direction of the parabolic mirror 10 passing outside the alignment mask 15.

The source 121 is positioned and oriented using the positioning and orientation means so that the incident optical beam 131 emitted by said source 121 is directed towards the hole of the alignment mask 15 and passes through said hole towards the parabolic mirror 10. If the source 121 is correctly positioned, the detector 16 detects, through the hole, an optical signal characteristic of the incident optical beam 131, for example an optical signal at the emission wavelength of the source 121. Said detector 16 then generates information representative of this detection and therefore representative of said detected optical signal characterizing the passage of the beam 131 through the hole, which makes it possible to validate the position and orientation of the source 121.

If the detector 16 is a flux detector, the adjustment of the position and the orientation of the source 121 is optimized when the detected flux is maximum, which corresponds to a maximum flux of the incident optical beam 131 emitted by the source passing through the alignment mask through the hole of said alignment mask 15. This optimization makes it possible to precisely adjust the position and orientation of the source 121. When the incident optical beam 131 does not pass through the focal point optical 11 of the parabolic mirror 10, it can be intercepted by the alignment mask 15 or be emitted in the direction of the parabolic mirror 10 outside the alignment mask 15. The detector 16 then does not detect any optical signal characteristic of the beam incident optic 131, for example,no optical signal at the emission wavelength of the source 121. The position and / or the orientation of the source 121 must in this case be changed until the detector 16 detects an optical signal characteristic of the beam incident optical 131 and then generates information representative of this detection which validates the position and orientation of the source.

When the position and orientation of a first source 121 are validated, the position and orientation of a second source 122 are adjusted by proceeding in the same manner as for the first source 121 using a detector sensitive to the wavelength emitted by said source 122 replacing detector 16. It is the same for the following sources.

Fig. 4 schematically illustrates a second positioning system for implementing the multispectral harmonization device.

The positioning system comprises in this example a detector 19, sensitive to the wavelength emitted by the source 121, and making it possible to verify the position and the orientation of a source 121. The detector 19 is oriented in the direction of the mirror. parabolic 10 and positioned opposite said parabolic mirror 10 with respect to the alignment mask 15. The detector 19 is preferably placed in a plane orthogonal to the optical axis and centered on the optical axis 17. When the incident optical beam 131 emitted by the source 121 passes through the hole of the alignment mask 15 and therefore through the optical focus 11, the reflected optical beam 141 propagates parallel to the optical axis 17 and is detected by the detector 19.Said detector 19 then generates information representative of said detected optical signal making it possible to validate the position and orientation of the source 121.

The detection surface of the detector 19 is at least equal to the opening of the parabolic mirror 10 so that any optical beam reflected by the parabolic mirror 10 parallel to the optical axis 17 is effectively detected by the detector 19.

If the detector 19 has a surface greater than the aperture of the parabolic mirror 10, it is necessary to further ensure that an optical beam reflected by the parabolic mirror 10 in a direction not parallel to the optical axis 17 cannot be detected by the detector 19, for example by sufficiently moving the detector 19 away from the parabolic mirror 10. The minimum distance between the optical focus 11 and the detector 19 depends on the outer diameter of the alignment mask 15, on the dimensions of the

detector 19 and the focal length of the parabolic mirror 10. This distance makes it possible to prevent an incident optical beam emitted by a source in the direction of the parabolic mirror 10 but passing outside the alignment mask 15 from being detected by the detector 19 and leads to an erroneous validation of the positioning of the source 121.

When the position and orientation of a first source 121 are validated, the position and orientation of a second source 122 are adjusted by proceeding in the same manner as for the first source 121 using a detector sensitive to the wavelength emitted by said source 122 which replaces detector 19. It is the same for the following sources.

Fig. 5 schematically illustrates a method for positioning and orienting the sources for the implementation of the multispectral harmonization device.

In a step 301, the parabolic mirror 10 is installed. In a step 302, the alignment mask 15 is positioned relative to the parabolic mirror 10 so that the hole of the alignment mask 15 coincides with the optical focus 11 of the parabolic mirror 10.

In a step 303, a source emitting a beam of wavelength l ί, for example the source 121 emitting at the wavelength li, is installed outside the field of the parabolic mirror 10 such that the optical beam emitted by said source is directed towards the parabolic mirror 10. In a step 304, a detector , of spectral band D1, including the wavelength Li emitted by the source to be aligned, is positioned so as to detect through the hole of the alignment mask 15 an optical signal corresponding to an optical beam coming from said source. For example, the detector 16 of spectral band Dlio including the wavelength li emitted by the source 121 is placed between the alignment mask 15 and the parabolic mirror 10 so as to be able to detect an incident optical beam 131.

In a step 305, the position and the orientation of the source are adjusted relative to the assembly constituted by the parabolic mirror 10 and the alignment mask 15 so that the optical beam emitted by said source, for example the incident optical beam 131 emitted by the source 121, passes through the hole of the alignment mask 15.

In a step 306, the position and the orientation of the source relative to the alignment mask 15 are checked. If the position and orientation are correct, the

spectral band detector Dl¾ detects an optical signal of wavelength l, and generates information representative of the detection of said optical signal, which validates the positioning and orientation of the source and leads to the execution of a step 307 If the position or orientation is incorrect, the detector does not detect an optical signal at wavelength Xi and step 305 is repeated. For example, if the incident optical beam 131 is detected by the detector 16, the position and the orientation of the source 121 are validated in order to go to step 307. If the detector 16 does not detect the incident optical beam 131, step 305 is repeated and the position and orientation of source 121 are again adjusted relative to alignment mask 15 until an optical signal is detected by detector 16.

In a particular embodiment, the adjustment of the position and the orientation of the source is optimized thanks to the use of a detector such as a flow detector. In this case, the position and orientation of the source are optimized when the detected flux is maximum, which corresponds to a maximum flux of the incident optical beam emitted by the source passing through the alignment mask through the hole of said alignment mask 15.

Step 307 consists in removing the spectral band detector Dl¾, such as for example the detector 16, from the system.

A step 308 consists in identifying whether the position and the orientation of at least one other source must be adjusted. If this is the case, step 303 is then repeated, which corresponds to the installation of another source emitting a beam of different wavelength, for example source 122 emitting at wavelength a. Then the following steps 304 to 308 are in turn repeated. If all the sources are correctly positioned and oriented, the implementation of the multispectral harmonization device is completed and a step 309 is performed.

In step 309, the multispectral collimated beam 18 generated by said multispectral harmonization device can be used to perform the harmonization operations of an optronic system, in particular to align the different channels of a system. optronics in different spectral bands.

In a particular embodiment, if the implementation of the multispectral harmonization device involves the successive adjustment of the positioning and orientation of two sources 121 and 122 emitting at respective wavelengths li and l different but both belonging to the spectral band Dlh of the same detector Dl, the detector DI used during the adjustment of the position and the orientation of the source 121 can be left in place after the validation of the position and of orientation of source 121: it is then possible to go directly from step 306 to step 308. When adjusting the position and orientation of source 122 and after installation of said source 122 in step 303, the detector DI being already in place, it is then not necessary to comply with step 304.

CLAIMS

1. Multispectral harmonization device intended to align the optical channels of an optronic system and comprising at least two directional optical sources (121 to 124) emitting respective optical beams of different wavelengths belonging to different spectral bands,

characterized in that said multispectral harmonization device further comprises a parabolic mirror (10) and means for positioning and orienting each of the optical sources so that each of the optical beams emitted (131 to 134) by said sources optical passes through the optical focus (11) of the parabolic mirror (10) before being reflected by said parabolic mirror (10) so that all of the optical beams (141 to 144) form by reflection on the parabolic mirror (10) ) a multispectral collimated beam (18),

and in that the positioning and orientation means comprise an alignment mask (15) consisting of an opaque wall and comprising a hole, said alignment mask being placed in a plane orthogonal to the optical axis of the parabolic mirror of such that the location of the hole corresponds to the optical focus (11) of the parabolic mirror.

2. Multispectral harmonization device according to claim 1, characterized in that the hole is centered on the alignment mask (15) and in that the dimension of the opaque wall is at least ten times greater than the dimension of said hole.

3. Multispectral harmonization device according to one of claims 1 and 2, characterized in that fixing means (20) removably assemble the alignment mask and the parabolic mirror.

4. Multispectral harmonization device according to one of claims 1 and 2, characterized in that fixing means (20) assemble the alignment mask (15) and the parabolic mirror (10) permanently and in that the external dimensions of the opaque wall are between 10 and 30% of the dimensions of the parabolic mirror (10).

5. Multispectral harmonization device according to claim 4, characterized in that the face of the opaque wall oriented towards the optical sources (121 to 124) is non-reflecting.

6. Multispectral harmonization device according to any one of claims 3 to 5, characterized in that the fixing means (20) are adjustable.

7. Multispectral harmonization device according to any one of claims 1 to 6, characterized in that the parabolic mirror (10) is divided into a number of sectors (201 to 204) equal to the number of channels of a optronic system to be harmonized, each of said sectors corresponds to a spectral band, and in that on each of the sectors is reflected at least one optical beam (131 to 134) from at least one optical source of emission wavelength belonging to the spectral band of the corresponding sector.

8. Positioning system comprising a multispectral harmonization device according to any one of claims 1 to 7, characterized in that the positioning and orientation means further comprise optical detection means (16, 19) , each optical detection means (16, 19) is sensitive to the emission wavelength of an optical source (121 to 124) to be positioned and oriented, each optical detection means (16,19) detects an optical signal at the emission wavelength of the optical source (121 to 124) if the optical beam (131 to 134) emitted by said optical source (121 to 124) passes through the hole of the mask d alignment (15) and does not detect an optical signal at the emission wavelength of the optical source if the optical beam (131 to 134) emitted by said optical source (121 to 124) does not pass through the hole the alignment mask,

and when an optical signal at the emission wavelength of the optical source is detected, said optical detection means (16, 19) generates information representative of the detection making it possible to validate the position and the orientation of the optical source (121 to 124).

9. A method of positioning and orienting at least two optical sources of a multispectral harmonization device, said sources emitting respective optical beams of different wavelengths belonging to different spectral bands,

characterized in that said positioning and orientation method comprises, for each of the optical sources (121 to 124), the steps of:

- installation (304) of an optical detector (16, 19) sensitive to the emission wavelength of said optical source to be positioned and oriented,

- adjustment (305) of the position and orientation of the optical source so that the optical beam emitted by said source is directed towards the parabolic mirror (10) and passes through a hole drilled in an alignment mask (15), the alignment mask (15) consisting of an opaque wall including the hole and being placed in a plane orthogonal to the optical axis of the parabolic mirror, the hole being located at the optical focus (11) of said mirror parabolic,

- detection (306), by the optical detector (16, 19) sensitive to the emission wavelength of the optical source (121 to 124), of an optical signal at said emission wavelength of the optical source, characteristic of the optical beam coming from said optical source which has passed through the hole, and generation of information representative of the detection.

10. Positioning and orientation method according to claim 9 characterized in that it further comprises a step of installing (302) of the alignment mask.

(15) so that the hole of said alignment mask (15) is located at the optical focus (11) of the parabolic mirror (10).

11. Positioning and orientation method according to one of claims 9 to 10, characterized in that it further comprises a step (307) of removing the optical detector (16, 19) sensitive to the length of emission wave from the optical source (121 to 124) when the positioning and orientation of said optical source (121 to 124) are validated.