GB1587698A

GB1587698A - Missiles including lasers suitable for missile and/or target tracking and for illumination purposes

Info

Publication number: GB1587698A
Application number: GB2522178A
Authority: GB
Original assignee: Precitronic Gesellschaft fuer Feinmechanik und Electronic mbH
Current assignee: Precitronic Gesellschaft fuer Feinmechanik und Electronic mbH
Priority date: 1977-10-03
Filing date: 1978-05-31
Publication date: 1981-04-08
Also published as: FR2404939B1; DE2744401A1; DE2744401C2; FR2404939A1

Description

(54) IMPROVEMENTS IN OR RELATING TO MISSILES INCLUDING LASERS SUITABLE FOR MISSILE AND/OR TARGET TRACKING, AND FOR ILLUMINATION PURPOSES (71) We, PRECITRONIC GESELLSCHAFT FUR FEINMECHANIK UND ELECTRONIC mbH, of Schützenstrasse 75-85, 2000 Hamburg 50, Federal Republic of Germany, a German Body Corporate, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to missiles including lasers suitable for missile and/or target tracking, and for illumination purposes.

The population inversion of the energy level of the laser material relative to the population distribution at thermal equilibrium, as is necessary for operating a laser, is attained by feeding energy with the help of a so-called pumping source. The type of pumping source for this purpose depends, inter giA, on the laser material used. Thus, for example, in the case of gas lasers excitation is produced by electron impact in a gas discharge, while the population inversion in the case of semiconductor lasers is produced directly by the electric current. In contrast, in the case of solid and liquid lasers, the necessary energy is irradiated from outside, perhaps in the form of light.

This optical pumping is attained with the aid of intensive light sources, for example flash-lamps, which illuminate very brightly on receiving a current surge. Because of the fact that such flashlamps operate as white radiators over a wide range of wavelengths, their pump efficiency for the laser is comparatively low, as they deliver too little energy for the relatively small pump transitions. Again, in order to produce the necessary pumping energy in the optical range, such pumped lasers operate mostly by pulsed operation. Moreover, the pumping light sources, for example flashlamps, which have been used up to the present time, are comparatively expensive, so that the use of such pumped lasers, for example in military missiles for missile and target tracking, is prohibited on cost grounds.This is particularly so in the case of cheap small-calibre missiles which are shot off in large numbers, and because of this there is a requirement for a cost-attractive "disposable" laser, which in addition is as insensitive as possible to impact, high acceleration etc.

According to the invention, there is provided a missile including a laser suitable for missile and/or target tracking and for illumination purposes, in which a pyrotechnic charge is provided as the pumping light source.

For example, for this purpose the known pyrotechnic charges of tracer missiles can be used, with if necessary the light colour of the pyrotechnic charge being modified by suitable additions in order to obtain a satisfactory pumping efficiency, i.e. the light colour of the pyrotechnic charge may be so adjusted that the largest possible proportion of the total light intensity can be used for the pumping operation.

The choice of the pyrotechnic charge material and its arrangement relative to the laser is desirably made such that the increase in pressure during burning is as small as possible, in order to prevent the disintegration of the laser material. For this purpose, it is advantageous to provide between the pyrotechnic charge and the laser material a suitable protection device which is pervious to the useful pumping light, for example quartz glass. Furthermore, the pyrotechnic charge material should burn as free as possible from soot and slag, in order to prevent any deposits on the laser material and/or on the said light-pervious protection device. which would absorb the pumping light.In this connection, it should be noted that the proportion of magnesium oxide in the pyrotechnic charge material is particularly critical in limiting or completely preventing such deposits, i.e. the composition of the pyrotechnic charge material is preferably optimised in this respect.

With the use of a pyrotechnic charge as the pumping light source, it is possible to produce simply constructed cost-attractive lasers. Furthermore, a preferred laser can operate continuously (cw laser), so that the intensity of radiation during the duration of the pyrotechnic charge can be varied such that the combustion of the pyrotechnic charge changes during the duration of burning by virtue of its form and composition.

This can for example be attained by making the spectral distribution and/or total light intensity of the pyrotechnic charge vary iwth time. Finally, as the pyrotechnic charge material can be distributed substantially as desired in the region of the combustion chamber, an optimum adaptation to the respective required form of the laser material is possible.

Thus, the pyrotechnic charge and the laser material may be disposed concentrically to each other, in order to obtain a simple geometrical structure.

In order to enable the luminescent plasma produced during combustion of the pyrotechnic charge to graze the laser material so so as to obtain optimum efficiency, it is advantageous to provide a combustion chamber between the laser material and pyrotechnic charge, with the pyrotechnic charge being advantageously provided with projections and cavities facing the combustion chamber in order to increase the combustion surface of the pyrotechnic charge.

In a preferred embodiment, the laser material is of rod form, and the pyrotechnic charge at least partly surrounds it concentrically. The reverse structure is equally simple, in which the laser material is of tubular form, and the pyrotechnic charge is disposed concentrically in the middle bore of the laser material.

If a fibrous laser material, for example a neodymium-doped quartz fibre, is used, this may be wound spirally and may be either surrounded concentrically by the pyrotechnic charge material or surround this latter.

In order to increase the efficiency of the laser, the combustion chamber walls which face away from the laser material and the wall behind the laser material facing away from the pyrotechnic charge may be metallised. By this means, unutilised light is in the first place reflected back to the laser material, so that the produced light energy can be utilised substantially for pumping the laser.

In order to make the retention time of the luminescent plasma, in the combustion chamber as long as possible and thus increase the efficiency of the pyrotechnic charge, the combustion chamber may be narrowed at its off-gas outlet end.

The laser light may leave the laser material at one or both ends of the laser material, and, for this purpose, one or both ends may be partially metallised in known manner.

In addition, at the light outlet ends of the laser material, additional optical devices, for example focusing or defocusing lenses, polarisation filters, photoconductors for guiding the emerging light in a given direction, etc., can be provided.

Because of the simple and compact structure and the low production cost of the preferred laser, it can be used particularly advantageously in small-calibre missiles, but its use is not limited to this.

In the case of previously used tracer missiles, the gunner himself or another observer has to track the missile with the aid of the tracer trajectory, in order to determine whether the missile lies on the sighted target, and, particularly when bombarding moving targets, in order to make continuous target corrections. However, with known tracer missiles, one drawback is that the gunner is easily dazzled by the tracer, in particular during unsatisfactory visual and weather conditions such as during the night, as the eyes of the gunner are already accustomed to the darkness. The time required for the eyes to become accustomed is however mostly slower than the present-day normal missile frequency, even when not every missile is in the form of tracer ammunition.

Furthermore, with the very high flight speeds of modern projectiles, tracking with the eye is difficult or indeed no longer possible. This is particularly true in the case of extra-high velocity artillery missiles, such as sabot missiles, without an explosive charge, which for example have recently been used for attacking tanks and are not distinguished by an explosion on impact. The hitting accuracy of such solid missiles can therefore be determined only in the rarest cases, and thus any substantial information for correcting the set value for the next shot is not available. Thus, as the missile ranges and speeds increase with advancing technology, there is no substantial improvement in the probability of a hit after the first shot.

For this reason, automatic steering devices have been developed for rockets and guided missiles, with the aid of which either the light-signal radiation from the rocket charge or a preferably intermittent pulsating electrical illuminating device is used as the reference signal for the remote steering. With the aid of sensors in the launching device, the flight position of the projectile or guided missile relative to the required target is determined automatically, while the gunner keeps his sighting device, for example an optical sight, set on the target. Both the axes, i.e. the sighting line and the missile axis, are then corrected automatically or semi-automatically, and this correlation function is fed, as required, to the missile in the form of a steering correction quantity.

However, such steering devices are easily deceived, for example by pyrotechnic combustible charges, which can either be discharged from the target under attack, or fired. The sensors of the attacking missile then pick up the intensive deceiving radiation as the target, and thus miss the actual target, as such steering devices are not able to distinguish between the genuine and deception targets.

In another known method, the missile trajectory is measured with the aid of radar.

However, such a method is not only technically difficult to carry out, but is also undesirable on tactical grounds, as the position of the radar antenna can be determined by the enemy from the radiation given off. For similar reasons, it is undesirable in the case of guided missiles and rockets to expose the launching position by actively radiating guide devices. Recently, for this reason passive infrared aR) devices have been used for determining the flight trajectory and for steering missiles. Preferably, IR light sources are provided for this purpose on the missile, and serve for automatically determining the missile position.However, such steering devices can be easily deceived, because for example targets which have already been shot up, e.g. burning tanks, are either automatically steered towards if automatic search heads are used, or the detectors in the automatic search head or in the missile tracking device are so strongly overload with radiation that they are unable to distinguish the weak working signals from the deceiving or noise signals.

Summarising, in the case of previously known missile and target tracking devices, allowance must be made either for deception by the attacked target, or for the danger of the position of the attacker becoming known by the enemy.

A preferred missile comprises a laser, which is optically pumped with the aid of the pyrotechnic charge as the pumping light source. It is indeed known to provide large missiles and bombs with lasers for target illumination; however, previously known lasers are not suitable for small-calibre missiles and in particular not suitable for highvelocity missiles such as sabot missiles, for cost and space reasons.

By the use of a preferred laser in smallcalibre missiles, their tracking is considerably simplified in comparison with the previously usual tracking ammunition, as the radiated light is coherent, and is less strongly absorbed and scattered over large distances, and thus the accuracy of the missile trajectory measurement is increased, for example when tracking the missile with the aid of optical devices.

If the required target is illuminated with the aid of the missile laser, then there is the particular advantage that, as the distance of the missile from the individual observer increases, i.e. as the missile increasingly approaches the target, the illumination intensity of the target increases, so that the accuracy of observation is improved as the target is approached.

The interpretation of the light radiated from the missile, or of the light reflected from the target, may be carried out with the aid of suitable known devices, for example opto-electronic video receivers, such as infrared night viewing apparatus and television apparatus, passive residual amplifiers or the like, so that the previously used interpretation devices can in most cases be further used. Preferably, the pictures which are taken are time-delayed, of residual image type and/or played back from an intermediate store, in order to be able to visually follow the succession of images at the high missile velocities. From the determined missile trajectory data the exact point of impact of the missile with, or its distance from, for example, aerial targets flying by, can be simultaneously calculated and determined with the aid of a process computer.

A particular advantage of the preferred missile is that the laser light is continuously radiated, i.e. the average radiated power is correspondingly high, so that even with a large distance between the missile and the observer, the measuring accuracy is very high, because the signal-noise ratio is satisfactory because of the high light intensity.

This can be further improved, for example by using suitable mixed pyrotechnic charges having a combustion intensity and thus a laser light intensity which is greater at the termination of combustion, i.e. in proximity to the target, than when the missile is launched.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a longitudinal section through a missile according to the invention, with rod-shaped laser material and a pyrotechnic charge surrounding this concentrically; Fig. 2a is a longitudinal partial section through a missile according to the invention, with tubular laser material and a pyrotechnic charge surrounding this concentrically; Fig. 2b is a view similar to Fig. 2a illustrating the operation of the laser; Fig. 3a is a longitudinal partial section through a missile according to the invention, with a cylindrical pyrotechnic charge surrounded by tubular laser material; Fig. 3b and 3c are views showing the operation of the laser according to Fig. 3a;; Fig. 4 is a longitudinal section through a solid missile with a cylindrical pyrotechnic charge, which is surrounded by fibrous laser material in coil form with two outlet ends; and Fig. 5 is a view similar to Fig. 4 of a further missile according to the invention with an explosive charge.

As shown in Figure 1, a missile 1 comprises a laser concentric to the missile axis, and which consists substantially of a rodshaped laser material 3 disposed along the missile axis and a tubular pyrotechnic charge 2 coaxial therewith. Between the laser material 3 and pyrotechnic charge 2 there is provided concentrically a combustion chamber 4, in which the luminescent plasma, with the aid of which the laser material 3 is opticaly pumped, is located when the pyrotechnic charge 2 burns.

The laser material is chosen basically according to the required radiation properties, for example according to whether operation is to be in the laser light range which is visible or invisible to the human eye, for example infrared. However, this choice must also take into account whether it is intended for the attacked target to be damaged, e.g.

by the radiation, or whether damage to the eyes of the gunner tracking the missile has to be prevented. In this latter case, it is advantageous to dope the laser material with erbium, as a laser formed in this manner operates in a wavelength range which is less damaging to the human eye.

In the laser shown in Figure 1, there is an outlet for the laser light provided at both ends of the rod-shaped laser material 3, the light outlet being effected in normal manner with the two resonator ends being partly metallised. If required, according to the particular application, optical devices can be provided at the front and/or end laser light outlet 5 and 6, in order for example to provide stronger bunching or greater divergence of the outflowing laser light beam. Thus for example in Fig. 1 an optical device 17 is provided at the front end of the missile, with the aid of which the outflowing laser light can be made to diverge in order to give improved target illumination.However, polarisation filters and/or suitable colour filters can be provided, in order to filter out a given laser light colour, if the laser material 3 used comprises several laser transitions.

The choice of composition of the pyrotechnic charge 2 is determined, on the one hand by the pumping energy of the laser material 3 used and on the other hand by the required variation of the laser light intensity with time. For this purpose, the various portions of the pyrotechnic charge are either homogeneously distributed, i.e.

the pyrotechnic charge burns over the total combustion duration with a constant light spectrum, or the spacial distribution of the various portions of the pyrotechnic charge is so chosen that the light intensity and/or the light spectrum varies in a required manner with time, thus varying the laser light radiation. In other respects, the pyrotechnic charges used correspond in their structure substantially to known pyrotechnic charges. As in the case of these latter, they are ignited at about the moment when the projectile is launched, and develop their maximum radiation either immediately or at a later point in time, such as shortly before the projectile hits its target.

With regard to the spacial shape of the pyrotechnic charge 2, it should be preferably ensured that the luminescent plasma evolved during combustion is able to give up its radiation energy as pumping energy to the laser material 3 over the greatest possible distance. For this reason, the hollow cylindrical combustion chamber 4 shown in Figure 1 is of longitudinally extended form, so that the luminescent plasma remains for a relatively long time in the combustion chamber 4 before its emergence at the missile end, and can optically pump the laser material 3.

In order to improve the combustion process, the pyrotechnic charge can be profiled in known manner on that side which faces the combustion chamber 4, as illustrated by the toothing 7 on the pyrotechnic charge 2 shown in cross-section in Fig. la. Instead of toothing 7 in the longitudinal direction of the pyrotechnic charge 2, spiral profiling can be porvided in order to increase the surface area of the pyrotechnic charge to improve the luminous effect and thus the pumping capacity for the laser.

In another embodiment shown in Figs. 2a and 2b, the laser material 13 can be of hollow cylindrical form, and be mounted by its bore on a pivot 18. The pyrotechnic charge 12 then surrounds the laser material 13 concentrically. In the illustrated embodiment, the pivot 18 is formed in one piece with the base of the hollow cylindrical space fo rthe pyrotechnic charge in the missile 1.

In the illustrated embodiment, the resonator surface 15 of the hollow cylindrical laser material 13 which faces away from the missile end is fully metallised, whereas the resonator surface 16 at the missile end is partly metallised for the delivery of the laser light.

The special pyrotechnic pumping charge 121, which is matched to the pumping energy of the laser material 13 used, can be disposed in a hollow cylindrical space at the opposite end to the outlet end for the luminescent plasma, so that initially a pyrotechnic charge 12 burns which because of its spectral distribution excites the laser material only slightly or not at all, and then the pyrotechnic pumping charge bums, so that its luminescent plasma grazes past the laser material with a high pumping efficiency.

In order to utilise the light energy of the luminescent plasma 12 to as great an extent as possible, the cylindrical surface of the pivot 18 is polished, or for example is meatllised by depositing rhodium by evaporation, so that the pumping light passing through the laser material 13 is again reflected back into the laser material 13. A sleeve 20 is preferably provided for the same purpose, it surrounding the pyrotechnic charge 12 concentrically and being metallised on that side facing the pyrotechnic charge 12.

In order to increase the retention time for the luminescent plasma in the combustion chamber, a constriction can be provided at the outlet end, formed for example by conically thickening the sleeve 20 towards the outlet end, as shown in the embodiment of Fig. 2a.

A pressure disc 21, preferably of brass, is preferably provided at the open end of the missile, somewhat as shown in Fig. 2a, so that it protects the laser against undesirable pressure when the missile 1 is launched.

Ignition ports 22 are provided in the pressure disc 21 for igniting the pyrotechnic charge 12. After launching the missile 1, the pressure disc 21 is separated or blown off in a suitable manner, so that the laser is unencumbered in the direction of the beam.

The substantially concentric radiation of the laser light 23 and luminous plasma 24 which then emerges is illustrated diagrammatically in Fig. 2b.

In the embodiment shown in Figs. 3a to 3c, the laser material 13 is of hollow cylindrical formation, as in the embodiment of Fig. 2a, and comprises a fully metallised resonator surface 15 and a partly metallised resonator end surface 16, from which the laser light 23 emerges. The laser material 13 is then embedded directly in the casing of the missile 1, while the pyrotechnic charge 25 is located in the bore of the tubular laser material 13. In order to optimise the utilisation of the light originating from the pyrotechnic charge for pumping the laser material 13, the surface of the casing 1 which faces the laser material 13 is preferably metallised, in order to reflect back into the laser material 13 the pumping light originating from the pyrotechnic charge 25 which passes through the laser material 13.As in the case of the pyrotechnic pumping charge 12l of the embodiment of Fig. 2a, a pyrotechnic pumping charge 251 can also be provided as shown in Fig. 3a axially displaced relative to the laser material 13.

The dashed lines in Fig. 3a show in this case how a constriction in the cross-section at the outlet end for the luminescent plasma can be obtained. For this purpose, a taper plug 26 which enlarges in cross-section towards the open end is provided preferably in the central region of the pyrotechnic charge 25, so that the space available for the combustion chamber narrows towards the outlet end for the luminescent plasma 24.

Instead of the cylindrical form for the laser material as shown in Figures 2a and 3a, an unillustrated conical form of laser material is also possible, whereby the pyrotechnic charge is disposed in the inside of the cone, or alternatively surrounds this cone in other embodiments. In these cases, the laser light can advantageously be radiated outwards from the summit of the cone, in which case the base surface of the hollow cone or solid cone acting as the resonator end surface would then be fully metallised.

If required, a photoconductor is connected to the partly metallised summit of the cone, in order to radiate the emerging laser light in the required direction.

In the embodiments shown in Figures 4 and 5, fibrous laser material 27 surrounds the pyrotechnic charge 38 in the form of a spiral or coil, with the pyrotechnic charge being preferably enclosed in a quartz cylinder 37, and the coil 27 being mounted thereon.

The laser material 27 consists preferably of a neodymium-doped quartz fibre, which is wound on the quartz cylinder 37 and disposed relative to the pyrotechnic charge 38 in such a manner that the burning plasma can pass through a combustion chamber on the inside of the quartz cylinder 37 and proferably escape axially backwards. As in the case of the previously described embodiments, in order to raise the efficiency the arrangement is preferably surrounded by a cylindrical support housing 41 which is internally metallised. This support housing can be formed for example directly by the missile casing. The ends of the quartz fibre 27 are preferably in the form of resonator end surfaces 29, 30, and are correspondingly metallised.The corresponding resonator end surfaces 30 and 29 are partly metallised and correspondingly aligned or are joined to a suitably disposed photoconductor 33, 43, according to whether the laser beam is required to be emitted backwards (31) and/ or forwards (36). These photoconductors 33 and 43 are led to the front end of the respective missile differentlv in the embodiments of Figs. 4 and 5. The solid missile 34 shown in Fig. 4 comprises no explosive charge and thus the photoconductor 33 can be led axially to the nose of the missile.

An optical device 35 is preferably provided at that point, in order to either bunch the laser beam 35 or, in another application, to cause it to diverge as required. In the embodiment of Fig. 5, the missile comprises an explosive charge 42, which takes up a substantial part of the front missile space. It is thus necessary to pass the light guide around this explosive charge 42, for example to an eccentric outlet point at the front end of the missile. Such an eccentric outlet for the laser beam at the front end of the missile can also be basically desirable, in particular to illuminate a larger target area, if the missile is rifled. Preferably, the optical devices 44 as heretofore described can be provided at the outlet end of the light guide.

In order to increase the efficiency of the laser, the combustion chamber with pyrotechnic charge 38 can be narrowed towards the outlet end for the luminescent plasma 32, this being preferably effected by means of a nozzle 39 as in Fig. 5. In addition, a pressure plate 40 can be preferably be provided at the missile end, in order to protect the laser against increased pressure on launching the missile, as heretofore described. This pressure plate 40 preferably blown off after launching the missile.

The fibre used for the laser material in the embodiments 4 and 5 is preferably a quartz fibre with a diameter of more than 0.5 mm, which is wound on the quartz cylinder 37 in the form of close turns, in order to produce an optimum laser pumping capacity.

In the case of small-calibre tracer ammunition, for example 20 mm tracer ammunition, a still thinner quartz fibre is preferably used, which can be wound with a small radius of curvature because of its elasticity.

Suitable account must be taken of the expected expansion of the quartz fibre on temperature rise during the burning of the pyrotechnic charge, by means of special constructional arrangements, for example by firmly embedding the spiral in the surrounding internally metallised laser housing 41.

Preferably, the arrangement of the quartz fibre can comprise more than one winding and/or a bi-filar construction, in order to increase the efficiency of the laser by increased absorption of the pumping light. If the radiation angle of the laser light, determined by the refractive index and diameter of the laser material, is to be varied, additional optical devices can be advantageously provided at the outlet ends of the laser.

In addition to the heretofore described general advantages of the described lasers, there is also the fact their incorporation in a missile provides an improved possibility of a hit, as there is both an improved tracking of the missile by the gunner or an observer with the aid of the rearward radiated laser beam, and/or an improved illumination of the sighted target by the forward radiated laser beam. In particular, exact interferencefree direction data can be determined, whereby for example any deceptive action carried out by the attacked target can be overcome by modulation and/or polarisation of the laser light with a given light frequency after corresponding decoding.If the trajectory of the missile is determined by optical tracking to obtain improved launching data for the next shot, then an improvement can be obtained in that the spacially sharply bounded laser beam of exactly defined light frequency can be exactly interpreted by suitably tuned measuring instruments and detectors.

The missile may include a detector for the laser light reflected from the target area arranged to activate a proximity fuse, and the detector may be arranged to respond selectively to the laser light with the aid of a filter.

WHAT WE CLAIM IS:- 1. A missile including a laser suitable for missile and/or target tracking and for illumination purposes, in which a pyrotechnic charge is provided as the pumping light source.

2. A missile as claimed in claim 1, in which between the pyrotechnic charge and the laser material there is provided a protection device of quartz which is pervious to the pumping light.

3. A missile as claimed in claim 1 or 2, in which the pyrotechnic charge and laser material are disposed concentric to each other.

4. A missile as claimed in claim 1 or 3, in which a combustion chamber is disposed between the laser material and pyrotechnic charge.

5. A missile as claimed in claim 4, in which, in order to increase the active surface of the pyrotechnic charge, the pyrotechnic charge is provided with projections and cavities facing the combustion chamber.

6. A missile as claimed in any one of claims 1 to 5, in which the laser material is of rod form, and the pyrotechnic charge at least partly surrounds it concentrically.

7. A missile as claimed in any one of claims 1 to 5, in which the laser material is of tubular form, and the pyrotechnic charge at least partly surrounds it concentrically.

8. A missile as claimed in claim 7, in which the tubular laser material is mounted on a concentric pivot.

9. A missile as claimed in any one of claims 1 to 5, in which the laser material is of tubular form and the pyrotechnic charge is disposed in the bore of the tubular laser material.

10. A missile as claimed in any one of claims 1 to 5, in which the laser material, in the form of a concentric coil, surrounds a substantially cylindrical pyrotechnic charge.

11. A missile as claimed in claim 10, in which the coil comprises multiple windings, and is bi-filar.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. explosive charge 42, which takes up a substantial part of the front missile space. It is thus necessary to pass the light guide around this explosive charge 42, for example to an eccentric outlet point at the front end of the missile. Such an eccentric outlet for the laser beam at the front end of the missile can also be basically desirable, in particular to illuminate a larger target area, if the missile is rifled. Preferably, the optical devices 44 as heretofore described can be provided at the outlet end of the light guide. In order to increase the efficiency of the laser, the combustion chamber with pyrotechnic charge 38 can be narrowed towards the outlet end for the luminescent plasma 32, this being preferably effected by means of a nozzle 39 as in Fig. 5. In addition, a pressure plate 40 can be preferably be provided at the missile end, in order to protect the laser against increased pressure on launching the missile, as heretofore described. This pressure plate 40 preferably blown off after launching the missile. The fibre used for the laser material in the embodiments 4 and 5 is preferably a quartz fibre with a diameter of more than 0.5 mm, which is wound on the quartz cylinder 37 in the form of close turns, in order to produce an optimum laser pumping capacity. In the case of small-calibre tracer ammunition, for example 20 mm tracer ammunition, a still thinner quartz fibre is preferably used, which can be wound with a small radius of curvature because of its elasticity. Suitable account must be taken of the expected expansion of the quartz fibre on temperature rise during the burning of the pyrotechnic charge, by means of special constructional arrangements, for example by firmly embedding the spiral in the surrounding internally metallised laser housing 41. Preferably, the arrangement of the quartz fibre can comprise more than one winding and/or a bi-filar construction, in order to increase the efficiency of the laser by increased absorption of the pumping light. If the radiation angle of the laser light, determined by the refractive index and diameter of the laser material, is to be varied, additional optical devices can be advantageously provided at the outlet ends of the laser. In addition to the heretofore described general advantages of the described lasers, there is also the fact their incorporation in a missile provides an improved possibility of a hit, as there is both an improved tracking of the missile by the gunner or an observer with the aid of the rearward radiated laser beam, and/or an improved illumination of the sighted target by the forward radiated laser beam. In particular, exact interferencefree direction data can be determined, whereby for example any deceptive action carried out by the attacked target can be overcome by modulation and/or polarisation of the laser light with a given light frequency after corresponding decoding.If the trajectory of the missile is determined by optical tracking to obtain improved launching data for the next shot, then an improvement can be obtained in that the spacially sharply bounded laser beam of exactly defined light frequency can be exactly interpreted by suitably tuned measuring instruments and detectors. The missile may include a detector for the laser light reflected from the target area arranged to activate a proximity fuse, and the detector may be arranged to respond selectively to the laser light with the aid of a filter. WHAT WE CLAIM IS:-

1. A missile including a laser suitable for missile and/or target tracking and for illumination purposes, in which a pyrotechnic charge is provided as the pumping light source.

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12. A missile as claimed in any one of claims 1 to 5, in which the laser material is in the form of a hollow cone.

13. A missile as claimed in claim 12, in which the pyrotechnic charge surrounds the hollow cone laser material.

14. A missile as claimed in claim 12, in which the hollow cone laser material surrounds the pyrotechnic charge.

15. A missile as claimed in any one of claims 1 to 14, in which constrictions are provided in the region of the open end of the combustion chamber.

16. A missile as claimed in claim 15, in which a throttle sleeve, a widening taper plug or nozzle is provided as a constriction.

17. A missile as claimed in any onc claims 1 to 16, in which the laser material is partly metallised at at least one end for the outlet of the laser light.

18. A missile as claimed in any one of claims 1 to 17, in which that side of the pyrotechnic charge facing away from the laser material is metallised.

19. A missile as claimed in any one of claims 1 to 18, in which that side of the laser material facing away from the pyrotechnic charge is metallised.

20. A missile as claimed in any one of claims 1 to 19, in which optical devices for the light are provided at the outlet ends of the laser material.

21. A missile as claimed in any one of the preceding claims, in which the pyro technic charge and the laser material are disposed concentrically to the missile axis.

22. A missile as claimed in any one of the preceding claims, in which the outlet for the laser light is at the missile end and/or at the missile nose.

23. A missile as claimed in claim 22, in which the outlet for the laser light is eccen tric to the missile axis.

24. A missile as claimed in any one of the preceding claims, in which photocon ductors are provided between the light outlet ends of the laser and the missile end and/or missile nose.

25. A missile as claimed in any one of the preceding claims, in which the laser together with the pyrotechnic charge form an insertion unit.

26. A missile as claimed in any one of the preceding claims, in which a pressure disc, which can be separated after launching, is provided at the outlet end for the luminescent plasma of the pyrotechnic charge.

27. A missile as claimed in claim 26, in which the pressure disc comprises at least one ignition port.

28. A missile as claimed in claim 26 or 27, in which the pressure disc is of brass.

29. A missile as claimed in any one of the preceding claims, including a detector for the laser light reflected from the target area arranged to activate a proximity fuse.

30. A missile as claimed in claim 29, in which the detector is arranged to respond selectively to the laser light with the aid of a filter.

31. A missile as claimed in any one of the preceding claims, including a steering device with a detector for varying the flight trajectory, arranged to respond to the laser beam reflected from the target.

32. A missile as claimed in any one of the preceding claims, in which the laser operates in the infrared region.

33. A missile as claimed in any one of the preceding claims, in which, in addition to the pyrotechnic charge as the pumping light source, there is provided a tracer charge arranged to excite the laser material only slightly or not at all.

34. A missile as claimed in claim 32, in which the pyrotechnic pumping charge is disposed at the other end of the laser material to the luminescent plasma outlet end.

35. A missile as claimed in claim 34, in which the tracer charge is adjacent to the luminescent plasma outlet end.

36. A missile substantially as hereinbefore described with reference to any one of the embodiments shown in the accompanying drawings.