FR2581205A1 - METHOD FOR RECORDING OPTOELECTRONIC AXES OF A THERMAL IMAGE APPARATUS - Google Patents

Abstract

PROCESS FOR BRINGING THE OPTOELECTRONIC AXIS INTO CONCORDANCE OF A THERMAL IMAGING APPARATUS WHICH INCLUDES, IN THE DIRECTION OF THE INCIDENT RADIATION, A DETECTOR CHANNEL WITH SCAN MIRROR AND SERIES OF DETECTORS. THE RADIATION ENERGY RECEIVED BY THIS LATTER IS REPRESENTED ON A SERIES OF LIGHT DIODES WHOSE RADIATION IS REFLECTED BY THE RESTITUTION SIDE OF THE SCAN MIRROR AND THROUGH THE THERMAL IMAGE CHANNEL, IN A SIGHT DEVICE IN WHICH THE OBSERVER MAY MAKE THE RETICLE AND THE OTHER AXES SUPERIMPOSE BY MEANS OF TURNING CORNERS PROVIDED IN THE THERMAL IMAGE CHANNEL, AND THEREFORE MAKE THESE AXES CONCORDANCE. THE RESTITUTION SIDE OF THE MIRROR IS DETECTED BY A SCAN POSITION SENSOR AND THE RADIATION REFLECTED FROM THIS SENSOR PRODUCES A TRIGGER SIGNAL IN ITS OWN DETECTOR.

Description

The subject of the present invention is a method for matching the

  optoelectronic axes of a thermal image device which comprises, in the direction of the incident radiation, a detection channel with an infrared optic, a scanning mirror, placed, in the rest position, at 45 relative to this optic, a infrared objective and a series of detectors, which b) represents the radiation energy received

  by the series of detectors, after optoelectro- conversion

  nique and amplification, on a series of LEDs

  corresponding minescents, c) reflects the radiation from the series of light-emitting diodes on a collimator objective, on the rendering side of the scanning mirror, and from there in a thermal image channel, consisting of a rendering optic and the eyepiece d an aiming device, and d) comprises a so-called scanning position sensor, the light source of which illuminates the projection side of the scanning mirror in order to detect its position and the reflected radiation of which produces a triggering signal by self-animation on its own detector,

  as well as a circuit for carrying out this process.

  German patent 33.29.590 describes a process of this type and a corresponding device. Furthermore, the German patents 30 48 809 and 31 04 318 disclose methods and arrangements in which a thermal image device is coupled with a laser transmitter so that the thermal image device

  serves as a reception channel for the laser transmitter.

  Finally, patent EP O 057 304 describes a combination of viewfinder devices comprising a channel

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  daylight, a residual light amplifier and a laser rangefinder. In this case, the different groups of devices are arranged parallel to each other and receive the incident radiation via a rotating mirror which is common to them. The laser rangefinder and the main target are inside the daylight channel, the latter being able to be reflected in the residual light amplifier provided as the night channel, in order to put

in agreement the axes.

  In these devices and device combinations, optoelectronic axes can be directed on a reticle serving as a reference and allow direct adjustment and aiming operations. However, they lack an additional possibility of exploiting the agreement achieved, such as the identification of time and position, for subsequent control operations.

or orientation.

  The object of the invention is to improve known sighting methods and corresponding apparatuses, so that their aligned optoelectronic axes can still be stored and exploited in another apparatus connectable if necessary, to the aiming apparatus, for an electronic representation of the objective or its thermal image. To this end, the method according to the invention is characterized in that: a multiplexer channel parallel to the channel of the thermal image is used for the electronic representation of the thermal image, with the possibility of connecting a deflection unit (follower) , the group of light-emitting diodes and the multiplexer channel are controlled with a group having matching functions directly or by the detector channel and the trigger signals are sent from the scanning position sensor to the multiplexer channel

  for synchronous interrogation of the detector.

  We thus obtain a signal in the form of a

  identification which corresponds to the reference axis -

  the reticle in a sighting device - and which can be used in place of it as a sighting line indicator, for example for a fully electronic tracker, mounted downstream. We can thus represent the position of the axis (aiming axis = reticle) that an observer, for example a shooter-pointer, uses in a telescope to aim an objective. This position is used by the follower to determine the deviation, for example of a flying machine, with respect to the axis, the reference axis being stored in the follower as

being the origin of the coordinates.

  The subclaims relate to

features of the invention.

  Different embodiments of the invention will be described below in more detail with reference to the accompanying drawing o the same references designate the same parts, and in which: FIG. 1 represents the functional diagram according to the invention with direct control of a multiplexer channel, FIG. 2 represents the functional diagram according to FIG. 1, but with control of the multiplexer channel via the detector channel mounted upstream of the first, and FIGS. 3a to 3d represent the different steps necessary for setting up concordance of optoelectronic axes. The thermal image apparatus 1 of FIG. 1 comprises an infrared optics 2 for the reception of infrared radiation 3 which reaches the detector 6 by the scanning device 4 and the objective of the

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  detector 5. After optoelectronic conversion, the detector signals are routed to the series of light-emitting diodes 9 by an amplifier 7, 8 and from there reflected in the sighting device 12, after passing through the channel of the thermal image 14 which consists of the collimator objective 10, on the rendering side of the scanning mirror 18 provided in the scanning unit 4, of the rendering optics 11 and of the rotating corners 17. The signals are thus represented to the observer 13. The thermal image apparatus 1 also comprises the scanning position sensor 19, the light source of which, not shown in the figure, illuminates the rendering side of the scanning mirror. The reflected radiation of restitution, produced by stickers, on a detector also not shown, a signal of

  trigger, used to trigger a pulse.

  So far, this is the known state of the art.

  Parallel to the thermal image channel

  14, the multiplexer channel is provided (= interrogation channel

  gation) 15 which, in the present embodiment, comprises the 15 'and 15 "units connected in series. It serves

  to the electronic representation of the thermal image.

  For an electronic channel of this type, it is necessary to capture the instantaneous horizontal position of the scanning mirror 18 and to put it in the form of electrical signals in order to ensure the synchronous electronic representation of the image, that is to say say the synchronous interrogation (= multiplexing) of the detector signals, for the follower 16 to be connected. We use it for this purpose

  of the scanning position sensor 19.

  The first unit 15 ′, in the direction of the signal flow, is controlled by a separate input by the processor 21 which in turn can be controlled by the control unit 20 having harmonic functions. In the present embodiment,

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  the amplifier 7, 8 also comprises two units, namely 7 and 8, whose amplification unit 8 is equipped with a

  exciter which controls the series of light-emitting diodes-

  centes 9 comprising for example 120 diodes, synchronously with the detector signals. The signal from the light-emitting diodes reaches, by the channel of the thermal image 14, described above, to the sighting device 12 made up of an optic. The input of the multiplexing unit 15 'is coupled between the two amplification units 7 and 8. According to another embodiment, the coupling of the unit 15' can be done between the detector

  6 and the amplifier 7, and the number of the electric diodes

  luminescent as well as that of the amplification and multiplexing units can be higher or lower,

  without departing from the scope of the invention.

  The thermal image channel 14 and the multiplexing channel 15 operate simultaneously. The optic 12 comprises inter alia a reticle 22 on which the two axes 14 and 15 are associated according to FIGS. 3a to 3d. To this end, the day image according to FIG. 3a, of a lens 23 is placed in the center of the reticle. In FIG. 3b, similar in its external appearance, we have switched to the thermal image channel 14 and we have

  placed the image represented by the series of electro-diodes

  luminescent 9 at the center of the reticle 22, by means of the rotating corners 17.. The channel of the thermal image 14 and the day channel are thus brought into agreement. As explained with the aid of FIG. 1, the processor 21 is now controlled by the control unit 20. It appears from FIG. 3c that in this case, for example 20 light-emitting diodes, each comprising 10 elements , are controlled separately, up and down, around the central element n 60 - in the numbering in the order of the diodes between n 50 and n 70 - so that, with the exception of the selected diode ,

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  all others are switched off, i.e. they are not lit. In the drawing, each square

  represents a diode and the black center square represents

  feel the lit diode supplied with current.

  Another solution is to darken all

  the diodes via a dimmer

  nosity, so that only the diodes selected are

  illuminated since ordered separately.

  In the particular embodiment of thermal image devices operating with displacement

  lines (for example 2: 1), after each operation of ex-

  ploration or scanning, the optical axis of the scanning device is tilted by the height of a

  detector. When selecting light emitting diodes-

  centes, described in the previous paragraph, the line displacement information, delivered by the scanning unit 4, can be used so as to allow displacement

  of a height corresponding to that of an electro-diode

  luminescent. In the present embodiment, this means that with the 20 diodes, one can select

lines.

  Figure 3d shows that with processor 21 (Figure 1) you can choose the light emitting diode which is covered by the horizontal line of the reticle

  22 (vertical direction) when illuminated. The ap-

  similar control 20 makes it possible to choose the pulse of the position sensor 19 for triggering the diode; the latter is illuminated when it is intersected by the vertical line of the reticle of the device 12. After these two adjustment measurements, a light-emitting diode lights up exactly in the center of the reticle, as indicated

  the blackened square in the center of figure 3d.

  The information number (information

  vertical) and the horizontal duration of illumination (inform-

  horizontal) of the series of light-emitting diodes-

  centes 9, are communicated according to figure 1, to the unit

  of multiplexing 15 'in the form of a corresponding voltage

  dante. Because of its amplitude, this pulse differs from all other background signals and objective signals, and can be used by the follower 16 as point 0 of the coordinates. The follower thus has

  the same position information of the reticle 22 of the apparatus

  reil 12, that observer 13, and can thus operate a

determination of the deviation.

  The embodiment of FIG. 2 differs from that of FIG. 1 only in that the control unit 20 and the processor 21 apply

  the voltage required to illuminate the electro-diode

  corresponding luminescent - and therefore the pulses (voltage) made available to the follower via multiplexing channel 15 - no longer by multiplexing channel 15, but by part 4 to 7 of the chosen detector channel, very exactly between

  the detector 6 and the amplification unit 7.

  According to an embodiment not shown in the figure, it would still be possible to provide for the control device 20 and the processor 21 to act on the detector channel, downstream of the amplification unit

  7, but upstream of the diversion between 7 and 8/15.

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Claims (15)

  1. Method for matching the optoelectronic axes of a thermal image device which: a) comprises, in the direction of the radiation   incident, a detection channel with infrared optics   red, a scanning mirror, placed, in the rest position, at 45 relative to this optic, an infrared objective and a series of detectors, b) represents the radiation energy received   by the series of detectors, after optoelectro- conversion   nique and amplification, on a series of LEDs   corresponding minescents, c) reflects the radiation from the series of light-emitting diodes on a collimator objective, on the rendering side of the scanning mirror, and from there in a thermal image channel, consisting of a rendering optic and the eyepiece d an aiming device, and d) comprises a scanning position sensor, the light source of which illuminates the rendering side of the scanning mirror in order to detect its position, and the reflected radiation of which produces a triggering signal by sticker animation on its own detector, characterized in that: e) a multiplexer channel (15) parallel to the channel of the thermal image (14) is used for the electronic representation of the thermal image, with the possibility of connecting a deflection unit (follower) (16), f) the series of light-emitting diodes (9) and the multiplexer channel (15) are controlled directly or by the detector channel (4 to 8) with a group having matching functions and g) on routes trigger signals from the sweep position sensor (19) to the channel 9 2581205   multiplexer (15) for synchronous interrogation of the detector (6).   2. Method according to claim 1, characterized in that one uses for the channel of the thermal image (14), an aiming device (12) comprising rotating corners (17), mounted upstream, directly on the radiation path, for adjusting the thermal image.   3. Method according to any one of the claims   1 or 2, characterized in that a) using the apparatus (12), place the daytime image of a lens (23) in the center of the reticle (22) and b) at the using rotating corners (17), place the thermal image represented by the series of light-emitting diodes (9) through the channel   of the thermal image (14), at the center of the reticle (22).   4. Method according to any one of the claims.   previous cations, characterized in that a group (20, 21) having matching functions is used, a processor (21) which can be controlled by a control device (20).   5. Method according to any one of the claims   tions 2 or 3, characterized in that the light emitting diode of the series (9) is selected, covered by the reticle (22) of the periscope (12), when it is   illuminated by the processor (21).   6. Method according to claim 4, characterized in that the pulse of the scanning position sensor (19) required for triggering (= lighting) of the series of light-emitting diodes (9) is selected by means of the control unit (20).   7. Method according to claims 1 to 3,   characterized in that the selection of the lines in the series of light-emitting diodes (9) is produced by the tilting of the thermal image apparatus (1) by means of a displacement of lines, it is doubly possible   choose by a back and forth movement (interlacing).   8. Method according to claim 7, character-   risé in that after scanning a line, the device (4) comprising the scanning mirror (18) is tilted by the height of a detector element, which triggers a displacement of corresponding height in the direction   of the series of light-emitting diodes (9).   9. Method according to any one of the claims   previous actions, characterized in that qubn routes the sequence number of the light emitting diodes towards   vertical and the duration of the lighting in the horizontal direction-   tale towards the multiplexer channel (15) in the form of a corresponding voltage, and from this to the unit of   deviation (16) to serve as the origin for the coordinates.   10. Circuit for implementing the process   according to any one of the preceding claims,   using a thermal image device the radiation energy of which falls, in order, by infrared optics on a scanning mirror arranged at 45 in   rest position, from there through an infra-   red on a series of detectors and this, after optoelectronic conversion and amplification, on a series of light-emitting diodes whose energy   radiation reaches, through an objective of collima-   on the rendering side of the scanning mirror to the eyepiece of an aiming device, while the light source of a scanning position sensor illuminates the rendering side of the scanning mirror and the radiation reflected by the latter by stickers, a trigger signal, characterized in that a multiplexer channel (15), for the electronic representation of the thermal image, with the possibility of connecting a deflection unit (16) is mounted parallel to the channel il of the thermal image (14), consisting essentially of the reproduction side of the scanning mirror (18), the reproduction optics (11) and the eyepiece (13) of the sighting device (12).   11. The circuit of claim -10, charac-   terized in that the multiplexer channel (15) comprises two multiplexing units (15 'and 15 ") connected in series, the first unit (15'), in the direction of signal flow, is supplied by the detector channel ( 4 to 8) alone or at the same time by the processor (21), and the second unit (15 ") in the direction of flow, is supplied by the detector channel and by the position sensor scan (19).   12. Circuit according to claim 11, characterized in that the processor (21) can be controlled by a control device (20) having functions to match.   13. The circuit of claim 11, character-   risé in that the input of the first multiplexing unit (15 '), in the direction of signal flow, is coupled between two amplification units (7, 8) of the detector channel (4 to 8).   14. Circuit according to any one of the claims   cations 11 to 13, characterized in that the control unit (20) and the processor (21) act on the channel   detector (14) downstream of the first amplification unit   tion (16) in the direction of the signal flow, but in   upstream of the derivation of its output (8, 15).   15. The circuit of claim 13, character-   in that the amplification unit (15 'or 15 ") is equipped with an exciter controlling the various light-emitting diodes of the series (9), so   synchronous with the detector signals.