LASER CONTROLLER

Abstract

There is provided a laser controller comprising: an electromagnetic radiation source operable to transmit radiation into the environment; a backscatter detector operable to detect backscattered radiation from the environment; and a processor operable to generate a laser control signal based on characteristics of the detected backscattered radiation.

Claims

1. A laser controller comprising: an electromagnetic radiation source operable to transmit radiation into an environment; a backscatter detector operable to detect backscattered radiation from the environment; and a processor operable to generate a laser control signal based on characteristics of the detected backscattered radiation.

2. The laser controller of claim 1, wherein the backscatter detector is operable to detect backscattered radiation resulting from operation of the electromagnetic radiation source.

3. The laser controller of claim 1, wherein the backscatter detector is operable to detect backscattered radiation at a first distance range relative to the electromagnetic radiation source.

4. The laser controller of claim 3, wherein the backscatter detector is operable to detect backscattered radiation within a plurality of distance ranges from the electromagnetic radiation source, starting with a first distance, and moving to one or more greater distances from the electromagnetic radiation source.

5. The laser controller of claim 1, wherein the processor is operable to generate a laser control signal based on intensity of the detected backscattered radiation.

6. The laser controller of claim 1, wherein the processor is operable to generate a laser control signal for selectively enabling and disabling operation of a laser controlled by the laser controller.

7. The laser controller of claim 1, wherein the processor is operable to generate a laser control signal for disabling operation of a laser controlled by the laser controller when the intensity of the detected backscattered radiation is above a cut-off threshold level.

8. The laser controller of claim 1, wherein the processor is operable to generate a laser control signal for modulating the operational power of a laser controlled by the laser controller according to the intensity of the backscattered radiation.

9. The laser controller of claim 8, wherein the processor is operable to generate a laser control signal for increasing the operation power of a laser controlled by the laser controller above a default power when the intensity of the backscattered radiation is between a first modulation threshold and a second modulation threshold.

10. The laser controller of claim 1, wherein the electromagnetic radiation source is a laser.

11. The laser controller of claim 1, wherein the backscatter detector comprises an interferometer.

12. The laser controller of claim 1, wherein the electromagnetic radiation source and backscatter detector comprise parts of a gas velocity sensor.

13. The laser controller of claim 1, operable to control a laser of a LDEW using the laser control signal.

14. A vehicle comprising the laser controller of claim 1.

15. A method of controlling a laser comprising: providing a laser controller according to claim 1; detecting by the backscatter detector of the background radiation transmitted by the electromagnetic radiation source; and generating by the processor of a laser control signal based on characteristics of the detected backscattered radiation.

16. The method of claim 15, wherein the method further comprises: providing a vehicle according to claim 14; and performing the method on the vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example only, to the accompanying diagrammatic drawings in which:

[0039] FIG. 1 is an illustration of a laser controller according to an example embodiment;

[0040] FIG. 2 is an illustration of a vehicle comprising a laser controller according to an example embodiment;

[0041] FIG. 3 depicts steps in a method according to an example embodiment.

DESCRIPTION OF EXAMPLE EMBODIMENTS

[0042] Referring now to FIG. 1, a laser controller is denoted as a whole by the reference numeral 100.

[0043] The laser controller 100 comprises an electromagnetic radiation source 101 operable to transmit radiation into an environment, a backscatter detector 102 operable to detect backscattered radiation from the environment, and a processor 103 operable to generate a laser control signal based on characteristics of the detected backscattered radiation. By detecting backscatter from the environment, the laser controller 100 can, using the processor 103, determine suitable operating parameters for a laser under its control. For example, if the laser controller 100 determines, based on a large amount of backscatter, that there is no clear light path from the laser to a target, then operation of the laser can be prevented. This avoids ineffective operation of the laser.

[0044] FIG. 2 shows a vehicle comprising the laser controller 100. In FIG. 2 the vehicle 200 comprising a laser controller 100 also comprises a laser 201. While the vehicle 200 is shown here as an aircraft, it would be readily appreciated that the present invention is applicable to other types of vehicles such as ships, land vehicles and so on.

[0045] The laser 201 is part of a laser-directed energy weapon 202 (LDEW), and the laser controller 100 is operable to control the laser 201 of the LDEW 202 using the laser control signal. Although here depicted as two separate components the laser controller 100 may be integral with the LDEW 202.

[0046] The backscatter detector 102 and electromagnetic radiation source 101 comprise parts of a gas velocity sensor that are part of the vehicle 200. The gas velocity sensor comprises a Doppler frequency shift sensor, such as that described in patent publication WO 2009/034370 A1, filed in the name of the present applicant, the contents of which are incorporated herein by reference. The gas velocity sensor is primarily used to determine airspeed of the vehicle, but includes an ultra violet laser source and an interferometer that can also be advantageously used as the electromagnetic radiation source 101 and backscatter detector 102 of the laser controller 100 respectively.

[0047] The backscatter detector 102 in use detects backscattered radiation at a first distance range relative to the electromagnetic radiation source 101. The backscatter detector 102, and electromagnetic radiation source 101 are operable together to detect backscattered radiation within a plurality of different distance ranges relative to the electromagnetic radiation source 101, starting with a first distance, and moving to one or more greater distances from the electromagnetic radiation source 101. In this way, an effective maximum effective range of the LDEW can be determined, that is, a range within which the light path to the target is not too contaminated. The processor 103 operates to generate a laser control signal on this basis, selectively enabling and disabling operation of the laser 201.

[0048] The processor 103 is generates a laser control signal based on characteristics of the detected backscattered radiation, including intensity of the detected backscattered radiation, as this is representative of the presence of contamination in the light path of the laser 201. The processor 103 is configured to generate a laser control signal for disabling operation of the laser 201 controlled by the laser controller 100 when the intensity of the detected backscattered radiation is above a cut-off threshold level, and conversely the processor 103 is configured to generate a laser control signal for enabling operation of the laser 201 controlled by the laser controller 100 when the intensity of the detected backscattered radiation is below the cut-off threshold level.

[0049] As well as enabling/disabling the laser 201 as described above, the processor 103 is further operable to generate a laser control signal that modulates the operational power of the laser 201 controlled by the laser controller 100, according to the intensity of the backscattered radiation. The processor 103 generates a laser control signal for increasing the operation power of the laser 201 controlled by the laser controller 100 above a default power when the intensity of the backscattered radiation is between a first modulation threshold and a second modulation threshold, so that an effective intensity is still delivered to a target despite some contamination in the light path.

[0050] Suitable optical arrangements are provided such that electromagnetic radiation source 101 transmits radiation in a direction aligned with the laser 201 of the LDEW 202, ideally along the same axis as the laser 201 of the LDEW. In another embodiment, the laser controller 100 is arranged to operate the laser 201 of the LDEW 202 as the electromagnetic energy source 101. Such embodiments do away with the requirement for a second laser source wen the laser controller 100 is used to control the laser of an LDEW.

[0051] FIG. 3 shows an example of a method of controlling a laser.

[0052] At step 300, an electromagnetic radiation source is operated to transmit radiation into an environment. At step 302, a backscattered detector is operated to detect backscattered radiation from the environment. At step 304, a laser control signal is generated based on characteristics of the backscattered radiation.

[0053] The method is performed by the laser controller, mounted to the vehicle.

[0054] The method further comprises controlling a laser of a LDEW using the laser control signal as step 306.

[0055] Steps 301 and 302 are conveniently performed using an electromagnetic radiation source and backscatter detector that comprise parts of a gas velocity sensor, such as a Doppler frequency shift sensor.

[0056] The method comprises operating the backscatter detector to detect backscattered radiation at a first distance range relative to the electromagnetic radiation source. In one example, the method comprises operating the backscatter detector to detect backscattered radiation within a plurality of different distance ranges relative to the electromagnetic radiation source, starting with a first distance, and moving to one or more greater distances from the electromagnetic radiation source. Thus, an effective maximum effective range of the LDEW can be determined, that is, a range within which the light path to the target is not too contaminated. Based on characteristics of the detected backscatter radiation, a laser control signal is generated, for selectively enabling and disabling operation of the laser.

[0057] The characteristics of the detected backscatter radiation include, for example, intensity of the detected backscattered radiation, as this is representative of the presence of contamination in the light path of the laser. A laser control signal for disabling operation of the laser controlled by the laser controller is generated when the intensity of the detected backscattered radiation is above a cut-off threshold level. Similarly, a laser control signal for enabling operation of a laser controlled by the laser controller is generated when the intensity of the detected backscattered radiation is below a cut-off threshold level.

[0058] As well as enabling/disabling the laser as described above, a laser control signal for modulating the operational power of a laser controlled by the laser controller according to the intensity of the backscattered radiation is generated. A laser control signal for increasing the operation power of a laser controlled by the laser controller above a default power is generated when the intensity of the backscattered radiation is between a first modulation threshold and a second modulation threshold, such that an effective intensity is still delivered to a target despite some contamination in the light path.

[0059] The method in one embodiment comprises operating the electromagnetic radiation source independently of a laser controlled by the laser control signal. In another embodiment, the method comprises operating the laser of an LDEW as the electromagnetic radiation source, eliminating the need for a second laser source, when the method is performed to control the laser of an LDEW.

[0060] Where, in the foregoing description, integers or elements are mentioned that have known, obvious, or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present disclosure, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the disclosure that are described as optional do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, while of possible benefit in some embodiments of the disclosure, may not be desirable, and can therefore be absent, in other embodiments.