FR2481794A1 - OPTICAL DEVICE FOR SPATIAL FIELD ANALYSIS AND ANGULAR LOCALIZATION OF A RADIANT OBJECT IN THIS FIELD - Google Patents

Abstract

OPTICAL DEVICE FOR ANALYSIS OF A SPACE FIELD AND ANGULAR LOCATION OF AN OBJECT RADIANT IN THIS FIELD. THE DEVICE FOR ANALYSIS OF A SPACE FIELD AND ANGULAR LOCATION OF AN OBJECT RADIANT IN THIS FIELD INCLUDES AN OPTICAL SYSTEM FOR SCANING THE FIELD AND A SYSTEM FOR DETECTIONING AND LOCATION OF SAID OBJECT. THIS OPTICAL SYSTEM INCLUDES AN OBJECTIVE 10 CONVERGENT OF REVOLUTION AROUND ITS OPTICAL AXIS AND AN OPTICAL ELEMENT WITH ROTATING PART AROUND AN AXIS XX 'OF ROTATION PARALLEL TO THAT OF THE OBJECTIVE, THE FOCAL PLANE OF SAID OPTICAL SYSTEM BEING PERPENDICULAR TO THE LENS. ROTATION AXIS. THE DETECTION SYSTEM INCLUDES A SYSTEM OF FIXED DETECTORS 15 IN THE FOCAL PLANE WHICH IS THE IMAGE PLAN OF THE FIELD OR ALSO MEANS FOR SCANING THE IMAGE PLAN USING THE OPTICAL IMAGE OF A FIXED DETECTOR. APPLICATION: DETECTION AND LOCATION OF TARGETS.

Description

"OPTICAL DEVICE FOR ANALYZING A SPATIAL FIELD AND LOCATION

  ANGULAR OF A RADIANT OBJECT IN THIS FIELD "

  The present invention relates to an optical device for analyzing a spatial field and angular location of an object

radiating in this field.

  It finds its application in the detection and the pursuit of an object emitting a radiation visible or not, called target afterwards, and enters the constitution of a homing device

  infrared equipping a vehicle guided automatically towards this target.

  In this type of application, an optical receiver is associated with a photoelectric detector to focus and detect

  radiation from the opening observation field determines

  nétet centered on the optical axis of sight. The received radiation comprises the useful radiation coming from the target to be detected and located when it is in the observed field, and the parasitic radiation

  produced by parasitic sources present in this field. Without

  additional fires the detection of the target is not done with a good signal-to-noise ratio. Indeed, the stream received from

  the target is usually weak in comparison with that corresponding to

  parasite from the background, ie from the space observed ex-

inside the target.

  It is known, for example, from French Patent No. 2,420,144, to increase the signal-to-noise ratio by producing a spatial scanning of the focused field image by a mobile mask provided with a grid device called "reticle" according to the terminology

  Anglo-Saxons, grids whose dimensions are determined in relation to

  with the image to be detected to produce a spatial filter for the reduction of parasitic sources whose dimensions are different from those of the target. These systems have the merit of being simple, working well when the target is alone

  in the system field or where the bottom is substantially uni-

  shape and that the contrast of the target from the bottom is good. Their fault is to provide false deviations in the presence of several targets of the same intensity in the field, for example artificial interference lures, when it comes to detecting military objectives, or natural as they meet in the landscape , clouds, horizon, terrestrial obstacles, the distinction between said targets can then no longer be made especially as these reticle systems do not allow from the signal delivered by the or

  detectors to reconstruct the image of the landscape.

  Other optical devices that can be used on

  Directors operate with a different principle. They are similar to optical-mechanical scanning cameras or television type, the analysis of the field taking place, in known systems, in two perpendicular directions. These cameras are able to provide the coordinates

  of points when every field. Self-helpers with these provisions

  sitives have a certain number of advantages: they make it possible to choose the target in the image and to adapt the analysis field to the dimensions of said target, this field being then very small from a very effective spatial filtering of the field ; image processing can be done by creating a processing window slaved to the designated target, which leads to the removal of natural jammers from the landscape (clouds, horizon, land obstacles) or artificial. The

  scanning system of these devices in two directions

  Diculaires is a relatively complicated design and, in the case of a missile, uses own mechanical means that do not exist.

on the missile.

  The invention proposes a system that does not have the same drawbacks as reticle devices and uses, for scanning the field, means generally existing on board a missile, more particularly the gyroscopic means for stabilizing the missile. The optical device according to the invention no longer uses a scan of the field in two perpendicular directions, but only a circular mechanical scan around an axis of rotation which, when the device is mounted on a missile, may be the one

  of the axis of the top of a gyroscope which is equipped with this missile.

  The analysis system offers the advantage of being simple and presenting a reduced field of analysis adapted to the dimensions of the target to be detected, which in fact leads to a very good spatial filtering efficiency with elimination of natural jammers of the landscape

or artificial.

  Thus, the device according to the present invention for

  lysis of a spatial field and location of a radiating object, in this field of the kind comprising an optical scanning system of the field and a system for detecting the image of the optical system and location of the object is remarkable in that that the optical scanning system of the

  field has in the direction of propagation beams of ray-

  from the spatial field - a convergent goal of revolution around its optical axis,

  an optical element comprising a rotating part

  turn of an axis called rotation parallel to that of the lens; said optical element being constituted and placed such that the focal plane of the entire optical system is perpendicular to said axis of rotation and rotates the image of the field in the so-called focal plane, and in that the detection system of the image of the optical system and location

  of the object includes a system of fixed detectors in the plane of the i-

  mage of the field or means for scanning said field image according to the given processes using the moving optical image of a fixed detector. According to a first embodiment of the invention, the axis of revolution of the convergent lens is coincident with said axis axis of rotation while said optical element with part

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  Turnaround, ftP is conceived of, it died that the focus is on

  that it is located on the axis of the target and rotates the imaget of the field around, focus in the focal plane of a double angle and revui of the rotation of said rotating part while the detection system of said image and location of the object comprises, a fixed sensor array in said focal plane, the detectors being arranged in urie or several rows, one end of this bar étar.tfordford with said home. The image of the rotating field scrolls on the fixed bar and the location of the object to be detected is done in polar coordinates.!), Being the distance

  between the image focus and the detector (s) (on which

  qe rbl'object and the angle between the bar and an origin direction

in the image plane.

  According to a variant of this first embodiment,

  said optical element comprises a fixed mirror

  in particular to said axis of rotation and a rotating part consisting of a set of two reflecting mirrors also inclined on

  the axis of rotation and forming right dihedral whose edge is perpendicular

dicular to this same axis.

  According to a second variant, said optical element is a set of three mirrors rotating about said axis of rotation, one of these mirrors being for example parallel to said axis of rotation, the other two having, for example, equal and opposite inclinations with respect to the first and relative to the axis of rotation, the three mirrors

  admitting the same normal plane passing through said axis of rotation.

  According to a third variant, said optical element is a Péchan prism rotating around an axis which is perpendicular

  to the planar entry and exit faces of said Péchan prism.

  According to a fourth variant, said optical element is a Wollaston prism rotating around an axis parallel to the face

reflective of said prism.

  According to a second embodiment, the axis of revolution of the lens is not coincident with said axis of rotation and said optical element with rotating part is the objective itself or one

  of its elements while the detection system, the image of loca-

  The object is a fixed array of detectors arranged along one or more rows of a length equal to that of the diameter of the field image explored by the optical system and whose center

  is located on the so-called axis of rotation. During the rotation of the ob-

  jectif, the image of each point of the field described in the image plane, an arc of a circle, in particular the image of the object to be detected, the latter being localized by means of respectively rectilinear and circular coordinates. According to a third embodiment of the invention, for which two sweeps of the field are made silmutaneously by means of the same rotational movement, the axis of the objective and the axis of rotation coincide and the detection and localization system of the object comprises a rotating drum with reflective faces, connected to the rotating part of the optical system, the faces being distributed around the axis of rotation, and an image transport of a detector

  fixed in the image plane of said optical system by means of optical elements

  and one of the faces of the drum, drum and transport of im-

  detector being arranged so that, during the rotation of the drum, the image of the detector describes a curve passing through the center of the field and symmetrical with respect thereto for each drum face involved in the transport of the drum. image, the curves described having the same shape for all the faces, but being shifted by one face

to the other.

  The invention will be better understood from the description

  following of some embodiments of the device of the invention

  given by way of non-limiting examples, said description being accom-

  accompanied by drawings that represent;

  Figure 1: a sectional view of a first embodiment of

  invention by the plane of symmetry perpendicular to the edge

  3U of the right dihedron of the rotating element.

  Figure 2 is a perspective view of the embodiment

previous placed on a missile.

  3: the relative movement of the detector with respect to the scene observed in the image plane, according to this first embodiment -6 -

  Figure 4: a view through the same section plane of a first

  first variant of this first embodiment provided with a teleobjector

  Figure 5: a sectional view of said first variant by the plane of symmetry parallel to the edge of the right dihedral of

the rotating element.

  Figure 6: a second variant of the rotating optical element, other than the right dihedral, used throughout the invention Figure 7: a third variant of this same element

rotating optics.

  Figure 8: a fourth variant of this same element

rotating optics.

  Figure 9: a sectional view through the plane of symmetry

  pendicular to the edge of the dihedron of a second variant of said first

embodiment.

  Figure 10 is a sectional view of a second embodiment of

  of the invention with an off-center and rotating lens, according to a

first variant.

  Figure 11 a view of relative motion in the plane

  image of the detector in relation to the landscape according to a second mode of

  embodiment of the invention for which the objective is off-center with respect to the axis of rotation

  Figure 12: a sectional view of a second embodiment of

  FIG. 13: a perspective view of a third embodiment of the invention with scanning of the image by means of the image.

a fixed detector.

  Figure 14: a diagram representing the relative movement

  of the image and a single-element detector according to the

positive of Figure 13.

  Figure 15: a schematic representation of the

previous movement.

  FIG. 16: a diagram representing this same relative movement of the image, with a detector comprising n elements mounted in series and arranged on a line perpendicular to the axis of rotation of FIG.

Figure 13.

  Figure 17: a diagram showing the same relative movement of the image with a detector having n x N elements mounted

  in parallel series and foriartt 'Vinnes perpendicular to the axis of rotation

  tation and n columns parallel to said axis.

  Figure 18: a sectional view perpendicular to the edge of the

  rotating dihedron of a first variant of the third embodiment.

  Figure 19. a sectional view perpendicular to the ridge

  of the rotating dihedron of a second variant of the third embodiment.

  In FIG. 1, relating to a first embodiment of

  X X 'designates the axis of the optical system

  cut in one of its planes of symmetry passing through this axis which

  at the same time is the line of sight of the seeker when the

tif is placed on a missile.

  This optical system comprises the convergent schematic system

  by the lens 10, the dihedron D right including the mirrors plan-

  11 and 12, and the plane mirror 13. The dihedron D and the mirror 13 which can be replaced by a reflective catadioptric system fold any optical ray from the scene to a point of the focal plane of the system passing through the focus F ' . The diadem has for this purpose a central hole 16 for the passage of the beams. Under 14 and 14 'are indicated two of these rays parallel to the axis X X' and which

  limit half of the beam from the scene in the direction

  aiming. This beam represented only in part for clarity

  drawing converges in F'I The dihedron is animated by a rotation movement

  around X X 'and rotate the image of the scene around the focus

  F '. In the focal plane is a fixed bar 15 composed of N de-

  sensors, one end of the bar being merged with the focus F '. The holders are arranged on the bar in one or more parallel rows. The detectors being placed for example,

  staggered from row to row and connected in series, the information

  The units are then clocked by means of delay lines.

  Preferably, the optical system is solidified

  of the object or missile with which it is associated, via a gyroscope fixed on said missile as shown in FIG.

2 by means of a cardan.

  In this figure the axes of the ca'rrJan are respectively 21 and 22 passing through the image focus FH of the optical system. The axis 22 is

  $ fixed with respect to the missile while the axis 21 is mobile around 22.

  The detector strip 15 is deposited along its large dimension on the moving axis 21. In this way, the detector is always in the focal plane of the optical system even when the X 'axis, common to the optical system and to the The spinning top of the gyroscope is not confused with the axis 23 of the missile. The lens 10, the mirrors 11, 12, 13 are shown in perspective. Under 6 is represented the beam coming from the scene in the direction of X X ', said flap cutting the dihedron following the section7.When the dihedron D turns by an angle a. around

  the X axis X ', the image of the scene rotates by a 2v angle. around F ', this

  image coming to form on the sensor array, the detector

  concerned by this image being all the more distant from FI than the directive

  Exploration is oblique to the line of sight. FIG. 3 shows the relative movement of the detector with respect to the image of the

  supposedly fixed landscape on the local plane of the optical system. Each

  Tector of the bar 15 scans a circular band such as the band 31; the detected target 32 being marked by its polar coordinates - and b preferentially, the device presents a

  large image print. To this end, according to a variant of the method of

  tion, the convergent part of the optical system is then constituted

  of a telephoto lens, which has the effect of reducing the central occultation

  the system for a given optical print. This variant is representative

shown in FIGS. 4 and 5.

  In FIGS. 4 and 5, the system is represented in

  pe, following its plane of symmetry, respectively perpendicular and parallel

  leash at the edge 8 of the dihedron. FIG. 4 shows the mirror 13 and the mirrors 11 and 12 of the right dihedron arranged on the block 45. The telephoto lens consists of the lenses 44 and 43, the image focus

248 1 94

  _9 of the whole system being in F 'on the X axis X'. To simplify the drawing, only the limit radii 41 and 42 from the examined scene are shown in the direction of the angle Y with the line of sight X X 'and corresponding to the upper half of the objective. The image of the scene in this direction is formed at the point P of the focal plane located in the planes of the figure. In Figure 5,

  only half of the system is represented. Limit radii in pro-

  venance of the examined scene in the direction making the angle y with

  the axis of view X X 'are 51, 52. The image of the scene in this

  This is formed in the plane of the figure at the point P 'of the focal plane. It is remarkable that an image inversion occurs when the plane of examination is perpendicular to the edge of the dihedral, whereas this inversion does not occur in a plane of examination parallel to this edge o the possibility for the system to rotate the image

  II of the scene at an angle double that of the rotation of the dihedron

  if, bring said image on one of the detectors of the bar. The right dihedral formed by two planar mirrors is not the only system that can be used to obtain the rotation of the image. Can be used any rotating optical system operating a recovery from

a map.

  Figures 6, 7,8 each represent in section one of

these systems.

  FIG. 6 shows the objective 10 whose optical axis coincides with the axis X X 'of rotation and whose focus is

  F '. The rotating element of the optical system around X X 'is constituted

  killed from the set of mirrors 61,62,63 integrally related to each other.

  The mirror 61 is for example parallel to the axis X X '. The mirrors 62 and 63 are, for example, also inclined with respect to 61 and by

relative to the X axis X '.

  In addition, the three mirrors admit the same normal plane passing through the axis X X '. In Figure 6, the beam 6 appears

  andthe path inside the rotating element of the optical ray

  fade with the optical axis of the lens, the image field is the circle

of diameter 60.

  In Figure 7, there is the objective 10 of optical axis coincides with X X 'and focus F'. The rotating element is the element of Wollaston 71 whose reflecting face is parallel to X X ', this axis being itself in a section normal to said faces. This element of Wollaston, since it operates in parallel light, precedes the objective 10. The beam 6 and the path inside the Uollaston of an optical ray coinciding with FIG.

  the X axis X '. The scanned image field is the diameter circle 70.

  In FIG. 8, the rotating element is the prism of Péchan 81, it rotates about the axis X X 'perpendicular to its faces

  planes of entry and exit. The scanned field is the circle of diam-

  80 be centered on the focus F '. Appears in the figure the beam 6 and the path inside the Péchan of an optical ray coincides with the axis X X '. Due to the blade 84 made of refractive index material

  different from that of the other parts of the prism, this ray emerges

offset from X X '.

  The optical systems described above are partly catadioptric. It goes without saying that they can also be entirely dioptric. Depending on the volume available and the problem to be solved, the convergent optical combination and the rectifier system are chosen

  (rotating part) the most appropriate.

  According to another variant, shown in section in Figure 9 by the plane of symmetry of the optical system perpendicular to the edge of the dihedron, are both reduced the dihedral hole and the central concealment of the entire system. The latter then has a primary objective 10, of focal length such that the focus F 'and the focal plane of the system comprising the objective 10, the mirror 13 and the dihedral are in the orifice 93 of the dihedron. An image is then transported from said focal plane in the image plane of the convergent system 92 perpendicular at A to the line of sight X X ', which plane contains the detector array, one of the ends of this strip being This embodiment has the advantage of using a scan of efficiency practically equal to unity (having no dead time) and of using few detectors. However, it has the disadvantage that the field is scanned at speeds not

- he -

  uniform and it follows that the pulses of radiation in

  targets on the detectors are becoming shorter and shorter.

  center, the central detector receiving a flow of

  tinu. According to a second embodiment, it is worn reme-

  from this nonuniformity of field exploration speed.

  The rotating optical element consists of the objective itself. The latter always turns around the so-called axis of rotation (coincides with the mechanical axis of the spinning top of a gyroscope when the device is installed on board). 'a missile) is off-center its plan

  focal remaining perpendicular to said axis of rotation.

  Figure 10 shows this embodiment. X X 'is the axis of rotation. 107 designates the optical axis of the lens when it is in the plane of the sheet. When rotating around X X ', 107 is at a constant distance from X X'. His home is FI. The analyzed field is, in the plane imagen, a circle centered on X X 'and of diameter F'F' '. Detection is effected by means of a detector array of length equal to this diameter. This bar is fixed in the image plane. It is placed on the axis 21 of the gimbal as in Figure 2, its

  center being the competition point of 21 and 22.

  FIG. 11 represents, in the focal plane of the optical system, the relative movement of the detectors with respect to the landscape. The

  circle 102 is the scanned image field. The detector NO 1 describes the cir-

  102 circle while the NO n detector describes the circumference

  fence of the circle 101 which is deduced from 102 by a parallel translation

  at the bar and module equal to the diameter of the image field.

  The bar 100, having double detectors as in the first embodiment, moves relative to the image of the position 103 to the position 104 while remaining parallel to itself.

  its extremities describing the circumferences of the circles 101 and 102.

  Each detector scans a band of the circular arc-shaped landscape image, such as 105. The position of a target 106 is then located along curvilinear coordinates, these coordinates being translatable by the calculation into rectangular coordinates. This system has the same range of bandwidth, which is the same for all types, but it does have the disadvantage that it has a less than unity efficiency since the surface field

  swept is the area of perimeter i. "OPQ with semi-circular boundaries

  while the useful field surface is the circle 102. On the other hand, the detector comprises twice as many elements with resolution

angular constant.

  According to a variant of this embodiment,

  12, the objective 10 is no longer a revolution and instead of 10 to be purely dioptric it is catadioptric. The objective comprises the partial optical system 108 coinciding with the axis of rotation X X 'and the set of mirrors which folds the beam 99 parallel to X X' and focuses it to F 'outside X X'. When the mirror 110 rotates around X X 'the lens analyzes the image diameter field

F 'Fi ".

  FIG. 13 shows a third embodiment where scanning of the image field is much more complex. The analysis of this field taking place in two directions using the same rotational movement. In this figure we find distributed around

  of the axis X X 'the objective provided with a dihedron identical to that of the first

  first embodiment and whose edge is assumed to be vertical in the plane of the figure the elements bearing the same references as in Figure 2. It is shown in its mount 111. This lens is connected to the drum 112 having mirrors. In this figure, the mirrors

  are interior. They can also be outside. One of these

  The interior has a number of fixed optical elements which, in cooperation with one of the faces of said drum, form the image of a detector 114 in the circular field 115 analyzed by the lens. and the movable dihedron. These elements

  are the reflecting mirror 116. the convergent element 117 of hearth 114.

  the convergent element 113 of focus 119 and the reflecting mirror 120, the

  mirrors 116 and 120 being perpendicular to the plane of the figure.

  Under 121 is shown an optical path of 119 to 114 through a reflexion on the face 113 of the drum,

3401 79 4

  said optical path being contained in the vertical plane passing through X X 'and the edge of the dihedron. At each turn of the optical block 111, the image of the scene rotates two turns in the plane of the image field 115 and the image 119 of the detector 114 by the drum 112 describes in the circular field 115 several axes of identical curves passing through the

  center of the field 115, with one curved arc per drum face.

  Some of these curve arcs are shown in Figure 14 in

  the plane of the field 115. One of these arcs is for example the arc 201.

  For ease of presentation and graphical representation,

  mile in Figures 13, 15,16,17, these arcs of curves to diameters

  of circle 115. For example, in FIG. 13, the image of the detector

  describes the diameter, 122 when the beam 121 is reflected on the mirror 113. The scan is shown in Figure 15 in the image field 115. Given the direction of rotation of the optical block 111, indicated

  in FIG. 13 by the arrow 123, the diameter 122 is scanned by the image

  il7 of the detector in the direction of the arrow 137 while the diameters

  very successive turn in the direction of the arrow 124, the diameters 125

  and 126 corresponding to the reflective faces 127 and 128 respectively. To improve the detection, the detector may comprise several

  elements in number n and arranged along a line perpendicular to the axis X ', the images of the n detectors describing each diameter as shown in FIG. 16, the detection taking place

  according to the serial mode with summation of the signals by means of delay lines.

  For the same purpose, the detector may comprise several elements in number

  n x N arranged along N rows of n columns, the columns and the

  gnes being respectively perpendicular and parallel to X X ', the detector then describing a diametrical band comprising N lines as shown in FIG. 17, the detection taking place according to FIG.

parallel series mode.

  FIG. 18 represents, by way of example, a first variant of this third embodiment in section through its plane of symmetry perpendicular to the edge of the rotating dihedron. In this figure we find the lens 10, the mirror 13 and the mirrors of

  dihedral 11 and 12 of Figure 1 included in the optical block 112.

  The rotating drum is pyramidal. Faces such as 151 and 152

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- 14 _

  are arranged externally on the same optical block. The circular image field 115 of the lens appears next.a line segment. The fixed system consisting of the convergent lens 153, the mirror 154, the lens 155 and the mirror 156 in cooperation with the rotating drum carries the image transport of the detector 114 outside the axis of rotation XX 'in the field of view. the objective and the dihedral When the beam is reflected on the face 151, the image of the detector sweeps the diameter 12Z, perpendicular to the plane of the sheet of the field

image of the lens.

  FIG. 19 is still in section according to its

  plane of symmetry perpendicular to the edge of the dihedron rotating a

  second variant of the third embodiment. The pyramidal drum has its reflective faces such as 159 and 160 looking towards the X 'axis on which the detector 114 is placed. Image transport

  of the detector 114 in the field of light 115 of the objective and the dia-

  dre is carried out using fixed lens elements and mirrors 161,

  162, 164, 165 in collaboration with the reflecting faces of the drum.

  bour. When the beam 121 is reflected on the face 159, the detector image described as in the previous example, the diameter1,22 of the

  2U circular image field perpendicular to the figure plane.

  The pyramidal shape was admitted for the tower drum.

  reflective. It can be designed from a prismatic form.

  The device according to this third embodiment, when it is used on a missile, uses, like the other embodiments, for axis XX 'the axis of the spinning top of the gyroscope, the detector 114 being placed at the intersection of the axes 21 and 22 of Figure 2 of the gimbal for fixing the gyroscope on the missile. As for the previous examples, the X 'axis X' is not necessarily coincident with the axis of the missile, but mobile around the center 114 of the gimbals. This third embodiment has the advantage of leading to a two-dimensional scanning by means of a single rotational movement, of analyzing the whole field by means of a small number of detectors, all the points of the field being analyzed at the same speed, to provide a very high redundancy

* information in the center of the field and get a very good feeling

  when using parallel serial type detection.

Claims (16)

CLAIMS -   1. Device for analyzing a spatial field and localising   angular representation of an object radiating in this field of the kind comprising an optical scanning system of the field and a system for detecting the image of the optical system and locating the object characterized   in that the optical scanning system of the field comprises in the   propagation rection of the radiation beams from the spatial field: a lens (10) converging in revolution around its optical axis,   an optical element comprising a rotating part   turn of an axis (XX ') said rotation parallel to that. of the objective, said optical element being constituted and placed such that the focal plane of the entire optical system is perpendicular to said axis of rotation,   in that the system for detecting the image of the optical system and the   calification of the object comprises a system of fixed detectors in the plane of the image of the field or means for scanning said image of the   field according to given processes using the optical image of a de- fixed head.   2. Device according to claim 1, characterized in that   that the optical axis of the objective and the said axis of rotation XX 'are   melted and in that said rotating part is constituted so as to rotate the image of the field with a circular contour of an angle   double that of the rotation of said rotating part.   3. Device according to claim 2, characterized in that   that the optical element with tounante part is placed behind the objective   tif (10) and in that it consists of a fixed mirror (13) for returning   placed perpendicular to the axis of rotation or a reflecting element   catadioptric, the rotating part being a set of plane reflective mirrors (11) (12) forming dihedral right whose edge (8)   perpendicular to the axis of rotation (XX '), the mirrors being   inclined on said axis of rotation.   4. Device according to claim 2, characterized in that the rotating optical element is a set of 3 mirrors (61), (62), (63) rotating about said axis of rotation, the three mirrors admitting   the same normal plane passing through said axis of rotation. 248 1794   r ^. Device according to Claim 2, characterized in that said optical element is a Péehari prism (81) rotating around it   an axis that is perpendicular to both faces; planes (82, (83. of   and out of said Péchan prism.   6. Device according to claim 2, characterized in that said optical element is a prism Wollaston '71) placed in front of   Lens (10) and rotating about an axle parallel to the reflective face of the said prism.   7. Device according to one of claims a to 6, characterized   in that the detector system is a strip (15. of linear shape   area, with several elements, fixed in relation to the rotational axis   and perpendicular to said axis, the elements being arranged in one or more rows, one end of said bar being   confused with the image focus (F ') of the optical system.   8. Device according to one of claims 1 to 6, characterized   characterized in that the detection system comprises a drum (112), said drum being provided with reflecting faces and rotating around it connected to said optical system regularly distributed around the axis of rotation, an image transport of a detector fixed (114) in the image plane of said optical system by means of fixed optical elements and one of the faces of the drum, drum and image transport of the   the detector being arranged in such a way that when the drum is rotated   bour, the image (119) of the detector describes a curve (201) passing through   the center of the field and symmetrical with respect to it for each   this drum involved in image transport. the curves   written with the same shape for all the faces but being shifted from one face to the other.   9. Device according to claims 3 and 8, characterized in   what the right dihedral of the rotating optical element and the (élémenrts   reflecting of the rotating drum are arranged on the same block.   10. Device according to claim 9, characterized in that   the detector (114) is outside the axis of rotation (XX ').   11. Device according to claim 9, characterized in that   the detector (114) is located on the axis of rotation (XX ').   12. Device according to one of claims 8 to 11, characterized   in that the detector has n elements arranged in a   line perpendicular to the axis of rotation.   13. Device according to one of claims 8 to 11, characterized   characterized in that the detector comprises n x N elements arranged   N rows and n columns, columns and rows being   perpendicularly and parallel to the axis of rotation. 14. Device according to claim 1, characterized in that the optical axis of the lens is not coincident with the axis (XX ')   said rotation and in that said optical element with   nante is the objective (10) itself while the image detection system and location of the object is a fixed bar (100) of detectors, arranged in one or more rows, the length of said bar being equal to that of the diameter of the field image   and its center being located on the axis of rotation.   15. Device similar to that according to claim 7,   because of the fact that the goal is not revolutionary   and has a rotating part (110) about the rotational axis   such that the focal plane remains perpendicular to and fixed with respect to the axis of rotation, the focus   around the axis of rotation a circle equal to the image of the field.   16. Homing system of a missile containing a stabilizer   gyroscope, characterized in that this homing device   carries an analysis device according to claim 7 whose axis of rotation coincides with the axis of the spinning top of the gyroscope, the image focus (F ') of the optical system being at the point of competition of the two axes (22) (21) of the gyroscope attachment gimbal on the missile, the sensor bar (15) being disposed on the movable axis (21) of this gimbal compared to the missile.   17. A homing system of a missile with stabilization   gyroscope, characterized in that this homing device   carries an analyzing device according to one of claims 8 to 13,   whose axis of rotation coincides with the axis of the spinning top of the gyros.   cope, the detector being placed at the point of competition of the two axes (22) (21) of the gyroscope.   18. A homing system of a missile with stabilization   gyroscope, characterized in that this homing device   carries an analysis device according to claim 14 or 15 of which   the axis of rotation coincides with the axis of the spinning top of the gyros.   cope, the sensor array being disposed on the axis (21) movable relative to the missile of the cardan fixing the gyroscope on the missile.