CA1234419A - Dual mode scanner/tracker - Google Patents
Dual mode scanner/trackerInfo
- Publication number
- CA1234419A CA1234419A CA000485428A CA485428A CA1234419A CA 1234419 A CA1234419 A CA 1234419A CA 000485428 A CA000485428 A CA 000485428A CA 485428 A CA485428 A CA 485428A CA 1234419 A CA1234419 A CA 1234419A
- Authority
- CA
- Canada
- Prior art keywords
- scanner
- tracker
- laser beam
- telescope
- magnified
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver
- G01S7/4812—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver transmitted and received beams following a coaxial path
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4817—Constructional features, e.g. arrangements of optical elements relating to scanning
Abstract
ABSTRACT
The beam of a laser radar is moved over the field of view by means of a pair of scanner/trackers arranged in cascade along the laser beam. One of the scanner/trackers operates at high speed, with high resolution and a narrow field and is located in the demagnified portion of the laser beam. The other scanner/tracker operates at low speed with low resolution and a wide field and is located in the magnified portion of the laser beam. The two scanner/trackers complement each other to achieve high speed, high resolution scanning as well as tracking of moving targets. A beam steering telescope for an airborne laser radar which incorporates the novel dual mode scanner/tracker is also shown.
The beam of a laser radar is moved over the field of view by means of a pair of scanner/trackers arranged in cascade along the laser beam. One of the scanner/trackers operates at high speed, with high resolution and a narrow field and is located in the demagnified portion of the laser beam. The other scanner/tracker operates at low speed with low resolution and a wide field and is located in the magnified portion of the laser beam. The two scanner/trackers complement each other to achieve high speed, high resolution scanning as well as tracking of moving targets. A beam steering telescope for an airborne laser radar which incorporates the novel dual mode scanner/tracker is also shown.
Description
This invention relates to optical radar of the type which illuminates targets by means of a laser beam and derives target information from the reflected laser beam. Such radars usually include a scanning and tracking capability. The scanning system moves the transmitted laser beam over the field of view, usually in some systematic manner, for example with a sawtooth scan system of the type used in television or with spiral type scanning. If such a radar is provided in addition with a tracking capability for moving targets, the scan format must be randomly programmable so that random target movements can be followed.
Scanner/trackers for laser beams may include a coarse scanner, for example a wide angle, low speed, low resolution scanner; with a narrow field, high resolution, high speed dither scanner in series with the coarse scanner. With such a dual mode scanner/tracker system, the coarse scanner may for example scan in a sawtooth fashion with gaps between the scanning lines, with the high speed dither scanner filling in the gaps. Thus the two scanners complement each other. In the tracking mode both of these scanner/trackers move in a programmed coordinated manner to achieve target tracking.
Scanners of this type usually achieve laser beam movement by means of moving optics such as rotating prisms or wedges through which the beam passes or electrically driven moving mirrors from which the beam is reflected. High speed tracking, such as is required for the aforementioned dither scanner/tracker requires extremely high power if the moving optics are located at a point where the laser beam has its largest diameter. Laser - 1 - 91~
radars normally include a means to expand the beam diameter before transmission to improve angular resolution or provide greater range.
According to one aspect of the present invention, there is provided a dual mode scanner/tracker system for an optical radar, said radar comprising a laser beam having magnified and demagnified portions, a first scanner/tracker located in said demagnified portion of said laser beam, said first scanner/tracker being high speed, high resolution and having a narrow field; a Ill second scanner/tracker located in the said magnified portion of said laser beam, said second scanner/tracker being lower speed, lower resolution and having a wider scan angle, relative to the same characteristics of said first scanner/tracker.
According to another aspect of the invention, there is provided the beam steering telescope of Claim wherein said first scanner/tracker comprises a pair of orthogonally mounted electrically driven reciprocating mirrors and said second scanner/tracker comprises a pair of transparent rotating wedges through which the said magnified laser beam passes. The beam steering telescope is thus capable of scanning its field of view 360D in azimuth while the dual mode scanner/trackers are operating.
In the accompanying drawings, which illustrate an exemplary embodiment of the present invention:
Figure 1 is a block diagram illustrating the concept of the novel dual mode scanner/tracker;
Figure 2 shows one way in which the novel concept of Figure 1 can be implemented;
SLY
Figure 3 shows additional details of the apparatus of Figure 2; and Figure 4 is a pictorial view of a beam steering telescope in which the novel dual mode scanner/tracker is integrated with the beam expanding telescope of the optical radar.
The diagram of Figure 1 shows a portion of an optical radar including narrow field scanner/tracker 5, a beam expanding telescope 7 which receives the output of scanner/tracker 5 and applies the expanded laser beam 13 to wide field scanner/
tracker 9, which radiates the laser beam into space, and receives laser target echoes. The narrow field scanner/tracker receives the narrow transmitted laser beam from the optical radar transceiver circuitry to the left thereof, now shown, and also applies the target echo signals passing there through to said radar circuitry.
A known method of achieving efficient scanning/tracking of optical radar beams is to provide two scanner/trackers in series or cascade along the beam with one scanner/tracker having a wide field of view, for example 60, low resolution and low scanning speed. Such a scanner/tracker must necessarily be located in the wide or expanded beam region of the laser beam.
The low resolution and low scanning speeds result in moderate power requirements for moving the necessarily large optics over such a large field of view. The low speed and low resolution of such a scanner/tracker can be enhanced by a narrow field, high resolution, high speed scanner/tracker in series therewith, with the beam movements of the two scanner/trackers designed to complement each other. For example, the narrow field scanner/tracker may have a 1 yield of view, referenced to the optical system output, which means that this scanner/tracker is capable of high speed, high resolution movement of the beam over this angle anywhere within the large field of view of the wide field scanner/tracker. In Figure 1, the angle 15 at the radar system output indicates the overall wide field of view of the radar with the smaller angle 17 representing the field of view due to the action of the narrow f old scanner/tracker. For example the angle 15 may be 60 and the angle 17, 1. The narrow field scanner/tracker could be located in the wide or expanded portion of the laser beam to the right of the beam expanding telescope, however the size of the moving optics required for such a location would have to be at least equal to the beam size Since moments of inertia of reciprocating or rotating mirrors or prisms go up with the square of the diameters thereof, the power requirements for achieving high speed, high resolution performance even over a small angle can be prohibitive. Significant power and consequent weight saving can be realized by locating the narrow field scanner/tracker in the narrow or demagnified portion of the laser beam, to the left of the beam expanding telescope as shown in Figure 1. At this location, the scanner/tracker optics can be scaled down to the approximate diameter of the narrow or demagnified laser beam, however the scanned field of view must be increased by the magnification of the beam expanding telescope.
For example, if the telescope 7 of Figure 1 has an focal magrlification of 20, the beam 13 in the output thereof will have a diameter 20 times the diameter of the beam 11 applied thereto from I
scanner/tracker 5, but the scan yield ox the expanded beam 13 will be reduced from the angle 12 at the telescope input, also by a factor equal to the telescope magnification. Thus if the scan field or angle 17 at the radar's output is to be lo in this example, the scanner/tracker 5 would be required to scan the beam 11 over the angle 12 equal to 20. Even with this larger scan field, the reduced size of the optics for the narrow field scanner/tracker results in power and weight savings.
The diagram of Figure 2 is one example of how the concept of Figure 1 can be implemented. In Figure I a portion of the optical radar circuitry is shown, including an optical duplexes 21 which directs the target echoes 37 to a receiver, not shown, and passes the narrow transmitted laser beam 19 to the narrow field scanner/tracker 25 via quarter wave plate 23. The high speed, narrow field, high resolution scanner/tracker 25 utilizes a pair of electrically driven reciprocating mirrors 27 and 31 which rotate around orthogonal axes 29 and 33 respectively to produce scanning or tracking with a bandwidth from do to over l.kHz. The mirrors are electrically driven as indicated by the arrows 35 labeled "Programmable Drives" and readouts 39 are provided for indicating instantaneous mirror positions. Such a scanner/tracker may have a 1 scan field, referred to the radar system output, with 3 x 103 elements per field (circular field with a diameter of 64 elements) and frame time of 1/30 second.
The effective aperture may be 0.5 cam with 0.02 random access resolution and 0.26 milliseconds random access time.
The output beam 40 of scanner/tracker 25 is applied Jo the input of the beam expanding telescope 43 via relay optics 41.
The relay optics may be required to keep the wide scan angle output of the scanner/tracker 25 within the small entrance pupil of telescope I The details of the relay optics and telescope are illustrated in more detail in Figure 3. The output beam 45 of telescope 43 will be a wide beam, for example 10 cm. in diameter if the narrow beam 40 is 0.5 cm. in diameter and telescope 43 has a rnagnifiacation of 20. Also the relatively wide scan field angle of the beam 40 will be reduced by this factor of 20, for example from 20 to 1 in the telescope output.
The wide field scanner/tracker 47 may comprise a pair of in-line rotating wedges or prisms 49 and 51 with apertures or diameters sufficient to accommodate the magnified scanned laser beam applied thereto from telescope 43. Such a rotating wedge scanner can have a total field of view of 60 with .6 random access resolution and a 20 milliseconds response time. The wedges 49 and 51 are separately driven as indicated by the arrows 53 labeled "Programmable Drives" and each has separate readouts 55 for indicating the position thereof. These versatile programmable scanner/trackers may be provided with a 16 bit optical shaft encoder as part of the readout system thereof for accurately monitoring the instantaneous scanner line of sight to within the diffraction limited resolution of the radar which is approximately 250 micro radians. Further details of such rotating wedge programmable scanner/trackers will be found in a co-pending Canadian patent application No. 426,681, entitled PROGRAMMABLE
SCANNER/TRACKER, Filed on 25 April 1983.
Dual in-line optical wedges may also be used for the narrow field high speed scanner 25, because of their superior performance in high vibration environments, for example such as would occur in an optical radar installed in a helicopter. Small aperture wedges for such an application would be competitive in frequency response to the reciprocating mirrors shown, but would require more signal conditioning to realize a tracking capability because of their non-linear transfer function.
Also, rather than using a pair of reciprocating mirrors for the scanner/tracker 25, a single mirror could be used, mounted on dual gimbals which are separately driven by the x and y LUG scanning signals. This arrangement may obviate the necessity for the relay optics 41.
The details of the relay optics 41 and the telescope 43 are shown in Figure 3. As can be seen the beam expanding telescope may comprise merely a pair of lenses 63 and 65 arranged along the optical axis 0-0. A beam directed into ocular or entrance pupil 63 will emerge from the objective lens I expanded in diameter and with a reduced scan field as explained above.
The relay optics 41 may comprise, for example, merely a single positive lens 61 positioned so that the narrow laser beam 40 from scanner/tracker 25 is concentrated at the entrance pupil 63 of the telescope 43, indicated by the converging rays 42.
Figure 4 shows a beam steering telescope which embodies the dual scanner/tracker of the present invention mounted in a rotatable turret 70 which is mounted on the underside of an aircraft 71. In this embodiment the narrow field scanner/tracker is integrated with the beam expanding telescope to reduce the number of optical components. The narrow laser beam 79 is applied to device 31 which includes both the narrow field scanner/tracker I
as well as the relay optics, if necessary, and the ocular lens of the beam expanding telescope, such as lens 63 of Figure 3. The beam 83 emerging from device 81 is reflected from fixed 45~ mirror 85 which is mounted along the axis of rotation 75 of turret 70.
The beam 87 then passes through the telescope objective lens 89 and is turned by another 90 by means of a second 45 mirror 91.
The beam 88 then passes through the wide angle scanner/tracker WhiCtl may comprise the two rotating wedges 95 and 97 plus ancillary apparatus, not shown, and emerges into space as the scanning beam 77. The arrow 73 represents the rotation of the turret around the axis 75.
While the invention has been described in connection with illustrative embodiments, obvious variations therein will occur to those skilled in this art, accordingly the invention should be limited only by the scope of the appended claims.
Scanner/trackers for laser beams may include a coarse scanner, for example a wide angle, low speed, low resolution scanner; with a narrow field, high resolution, high speed dither scanner in series with the coarse scanner. With such a dual mode scanner/tracker system, the coarse scanner may for example scan in a sawtooth fashion with gaps between the scanning lines, with the high speed dither scanner filling in the gaps. Thus the two scanners complement each other. In the tracking mode both of these scanner/trackers move in a programmed coordinated manner to achieve target tracking.
Scanners of this type usually achieve laser beam movement by means of moving optics such as rotating prisms or wedges through which the beam passes or electrically driven moving mirrors from which the beam is reflected. High speed tracking, such as is required for the aforementioned dither scanner/tracker requires extremely high power if the moving optics are located at a point where the laser beam has its largest diameter. Laser - 1 - 91~
radars normally include a means to expand the beam diameter before transmission to improve angular resolution or provide greater range.
According to one aspect of the present invention, there is provided a dual mode scanner/tracker system for an optical radar, said radar comprising a laser beam having magnified and demagnified portions, a first scanner/tracker located in said demagnified portion of said laser beam, said first scanner/tracker being high speed, high resolution and having a narrow field; a Ill second scanner/tracker located in the said magnified portion of said laser beam, said second scanner/tracker being lower speed, lower resolution and having a wider scan angle, relative to the same characteristics of said first scanner/tracker.
According to another aspect of the invention, there is provided the beam steering telescope of Claim wherein said first scanner/tracker comprises a pair of orthogonally mounted electrically driven reciprocating mirrors and said second scanner/tracker comprises a pair of transparent rotating wedges through which the said magnified laser beam passes. The beam steering telescope is thus capable of scanning its field of view 360D in azimuth while the dual mode scanner/trackers are operating.
In the accompanying drawings, which illustrate an exemplary embodiment of the present invention:
Figure 1 is a block diagram illustrating the concept of the novel dual mode scanner/tracker;
Figure 2 shows one way in which the novel concept of Figure 1 can be implemented;
SLY
Figure 3 shows additional details of the apparatus of Figure 2; and Figure 4 is a pictorial view of a beam steering telescope in which the novel dual mode scanner/tracker is integrated with the beam expanding telescope of the optical radar.
The diagram of Figure 1 shows a portion of an optical radar including narrow field scanner/tracker 5, a beam expanding telescope 7 which receives the output of scanner/tracker 5 and applies the expanded laser beam 13 to wide field scanner/
tracker 9, which radiates the laser beam into space, and receives laser target echoes. The narrow field scanner/tracker receives the narrow transmitted laser beam from the optical radar transceiver circuitry to the left thereof, now shown, and also applies the target echo signals passing there through to said radar circuitry.
A known method of achieving efficient scanning/tracking of optical radar beams is to provide two scanner/trackers in series or cascade along the beam with one scanner/tracker having a wide field of view, for example 60, low resolution and low scanning speed. Such a scanner/tracker must necessarily be located in the wide or expanded beam region of the laser beam.
The low resolution and low scanning speeds result in moderate power requirements for moving the necessarily large optics over such a large field of view. The low speed and low resolution of such a scanner/tracker can be enhanced by a narrow field, high resolution, high speed scanner/tracker in series therewith, with the beam movements of the two scanner/trackers designed to complement each other. For example, the narrow field scanner/tracker may have a 1 yield of view, referenced to the optical system output, which means that this scanner/tracker is capable of high speed, high resolution movement of the beam over this angle anywhere within the large field of view of the wide field scanner/tracker. In Figure 1, the angle 15 at the radar system output indicates the overall wide field of view of the radar with the smaller angle 17 representing the field of view due to the action of the narrow f old scanner/tracker. For example the angle 15 may be 60 and the angle 17, 1. The narrow field scanner/tracker could be located in the wide or expanded portion of the laser beam to the right of the beam expanding telescope, however the size of the moving optics required for such a location would have to be at least equal to the beam size Since moments of inertia of reciprocating or rotating mirrors or prisms go up with the square of the diameters thereof, the power requirements for achieving high speed, high resolution performance even over a small angle can be prohibitive. Significant power and consequent weight saving can be realized by locating the narrow field scanner/tracker in the narrow or demagnified portion of the laser beam, to the left of the beam expanding telescope as shown in Figure 1. At this location, the scanner/tracker optics can be scaled down to the approximate diameter of the narrow or demagnified laser beam, however the scanned field of view must be increased by the magnification of the beam expanding telescope.
For example, if the telescope 7 of Figure 1 has an focal magrlification of 20, the beam 13 in the output thereof will have a diameter 20 times the diameter of the beam 11 applied thereto from I
scanner/tracker 5, but the scan yield ox the expanded beam 13 will be reduced from the angle 12 at the telescope input, also by a factor equal to the telescope magnification. Thus if the scan field or angle 17 at the radar's output is to be lo in this example, the scanner/tracker 5 would be required to scan the beam 11 over the angle 12 equal to 20. Even with this larger scan field, the reduced size of the optics for the narrow field scanner/tracker results in power and weight savings.
The diagram of Figure 2 is one example of how the concept of Figure 1 can be implemented. In Figure I a portion of the optical radar circuitry is shown, including an optical duplexes 21 which directs the target echoes 37 to a receiver, not shown, and passes the narrow transmitted laser beam 19 to the narrow field scanner/tracker 25 via quarter wave plate 23. The high speed, narrow field, high resolution scanner/tracker 25 utilizes a pair of electrically driven reciprocating mirrors 27 and 31 which rotate around orthogonal axes 29 and 33 respectively to produce scanning or tracking with a bandwidth from do to over l.kHz. The mirrors are electrically driven as indicated by the arrows 35 labeled "Programmable Drives" and readouts 39 are provided for indicating instantaneous mirror positions. Such a scanner/tracker may have a 1 scan field, referred to the radar system output, with 3 x 103 elements per field (circular field with a diameter of 64 elements) and frame time of 1/30 second.
The effective aperture may be 0.5 cam with 0.02 random access resolution and 0.26 milliseconds random access time.
The output beam 40 of scanner/tracker 25 is applied Jo the input of the beam expanding telescope 43 via relay optics 41.
The relay optics may be required to keep the wide scan angle output of the scanner/tracker 25 within the small entrance pupil of telescope I The details of the relay optics and telescope are illustrated in more detail in Figure 3. The output beam 45 of telescope 43 will be a wide beam, for example 10 cm. in diameter if the narrow beam 40 is 0.5 cm. in diameter and telescope 43 has a rnagnifiacation of 20. Also the relatively wide scan field angle of the beam 40 will be reduced by this factor of 20, for example from 20 to 1 in the telescope output.
The wide field scanner/tracker 47 may comprise a pair of in-line rotating wedges or prisms 49 and 51 with apertures or diameters sufficient to accommodate the magnified scanned laser beam applied thereto from telescope 43. Such a rotating wedge scanner can have a total field of view of 60 with .6 random access resolution and a 20 milliseconds response time. The wedges 49 and 51 are separately driven as indicated by the arrows 53 labeled "Programmable Drives" and each has separate readouts 55 for indicating the position thereof. These versatile programmable scanner/trackers may be provided with a 16 bit optical shaft encoder as part of the readout system thereof for accurately monitoring the instantaneous scanner line of sight to within the diffraction limited resolution of the radar which is approximately 250 micro radians. Further details of such rotating wedge programmable scanner/trackers will be found in a co-pending Canadian patent application No. 426,681, entitled PROGRAMMABLE
SCANNER/TRACKER, Filed on 25 April 1983.
Dual in-line optical wedges may also be used for the narrow field high speed scanner 25, because of their superior performance in high vibration environments, for example such as would occur in an optical radar installed in a helicopter. Small aperture wedges for such an application would be competitive in frequency response to the reciprocating mirrors shown, but would require more signal conditioning to realize a tracking capability because of their non-linear transfer function.
Also, rather than using a pair of reciprocating mirrors for the scanner/tracker 25, a single mirror could be used, mounted on dual gimbals which are separately driven by the x and y LUG scanning signals. This arrangement may obviate the necessity for the relay optics 41.
The details of the relay optics 41 and the telescope 43 are shown in Figure 3. As can be seen the beam expanding telescope may comprise merely a pair of lenses 63 and 65 arranged along the optical axis 0-0. A beam directed into ocular or entrance pupil 63 will emerge from the objective lens I expanded in diameter and with a reduced scan field as explained above.
The relay optics 41 may comprise, for example, merely a single positive lens 61 positioned so that the narrow laser beam 40 from scanner/tracker 25 is concentrated at the entrance pupil 63 of the telescope 43, indicated by the converging rays 42.
Figure 4 shows a beam steering telescope which embodies the dual scanner/tracker of the present invention mounted in a rotatable turret 70 which is mounted on the underside of an aircraft 71. In this embodiment the narrow field scanner/tracker is integrated with the beam expanding telescope to reduce the number of optical components. The narrow laser beam 79 is applied to device 31 which includes both the narrow field scanner/tracker I
as well as the relay optics, if necessary, and the ocular lens of the beam expanding telescope, such as lens 63 of Figure 3. The beam 83 emerging from device 81 is reflected from fixed 45~ mirror 85 which is mounted along the axis of rotation 75 of turret 70.
The beam 87 then passes through the telescope objective lens 89 and is turned by another 90 by means of a second 45 mirror 91.
The beam 88 then passes through the wide angle scanner/tracker WhiCtl may comprise the two rotating wedges 95 and 97 plus ancillary apparatus, not shown, and emerges into space as the scanning beam 77. The arrow 73 represents the rotation of the turret around the axis 75.
While the invention has been described in connection with illustrative embodiments, obvious variations therein will occur to those skilled in this art, accordingly the invention should be limited only by the scope of the appended claims.
Claims (7)
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A dual mode scanner/tracker system for an optical radar, said radar comprising a laser beam having magnified and demagnified portions, a first scanner/tracker located in said demagnified portion of said laser beam, said first scanner/tracker being high speed, high resolution and having a narrow field, a second scanner/tracker located in the magnified portion of said laser beam, said second scanner/tracker being low speed, low resolution and having a wide scan angle, said two scanner/trackers being each driven by programmable drives which complement each other to produce efficient scanning of said laser beam and efficient tracking of randomly moving targets in the field of view of said optical radar.
2. The system of Claim 1 wherein said first and second scanner/trackers are separated by a beam expanding telescope, said beam expanding telescope comprising an entrance pupil.
3. The system of Claim 2 wherein said first scanner/tracker comprises a pair of orthogonally mounted, electrically driven reciprocating mirrors which produce linear sawtooth scanning with a bandwidth from zero tro 1.0 kHz, relay optics located at the output of said first scanner/tracker arranged to constrain the output of said first scanner/tracker to the said entrance pupil of sead beam expanding telescope, said second scanner/tracker comprising a pair of in-line, transparent, rotating wedges or prisms, said wedges having separate programmable drives and separate readouts for indicating the instantaneous wedge positions.
4. A beam steering telescope forming part of an airborne optical radar, comprising; an aircraft, a rotating turret mounted on the underside of said aircraft, said beam steering telescope comprising a first high speed, high resolution and narrow field scanner/tracker located in the demagnified portion of the laser beam of said optical radar, the output of said first scanner/
tracker being applied to a beam expanding telescope the output of which is a magnified laser beam, a fixed 45° mirror aranged to direct the said output of said beam expanding telescope along the axis of rotation of said turret to another fixed 45° mirror which directs said expanded beam through a second scanner/tracker which has a wide field, low resolution, and low scanning speed.
tracker being applied to a beam expanding telescope the output of which is a magnified laser beam, a fixed 45° mirror aranged to direct the said output of said beam expanding telescope along the axis of rotation of said turret to another fixed 45° mirror which directs said expanded beam through a second scanner/tracker which has a wide field, low resolution, and low scanning speed.
5. The beam steering telescope of Claim 4 wherein said first scanner/tracker is integrated with said beam expanding telescope.
6. The beam steering telescope of Claim 4 wherein said first scanner/tracker comprises a pair of orthogonally mounted electrically driven reciprocating mirrors and said second scanner/tracker comprises a pair of transparent rotating wedges through which the said magnified laser beam passes.
7. A dual mode scanner/tracker system for an optical radar, said radar comprising a laser beam having magnified and demagnified portions, a first scanner/tracker located in said demagnified portion of said laser beam, said first scanner/tracker being high speed, high resolution and having a narrow field; a second scanner/tracker located in the said magnified portion of said laser beam, said second scanner/tracker being lower speed, lower resolution and having a wider scan angle, relative to the same characteristics of said first scanner/tracker.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/669,912 USH341H (en) | 1984-11-09 | 1984-11-09 | Dual mode scanner/tracker |
| US669,912 | 1984-11-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1234419A true CA1234419A (en) | 1988-03-22 |
Family
ID=24688233
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000485428A Expired CA1234419A (en) | 1984-11-09 | 1985-06-26 | Dual mode scanner/tracker |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | USH341H (en) |
| CA (1) | CA1234419A (en) |
Cited By (2)
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| EP3579174A1 (en) | 2018-06-08 | 2019-12-11 | Hexagon Technology Center GmbH | Mobile vehicles in manufacturing |
| CN111694009A (en) * | 2020-05-07 | 2020-09-22 | 南昌大学 | Positioning system, method and device |
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| US5202742A (en) * | 1990-10-03 | 1993-04-13 | Aisin Seiki Kabushiki Kaisha | Laser radar for a vehicle lateral guidance system |
| US5390118A (en) * | 1990-10-03 | 1995-02-14 | Aisin Seiki Kabushiki Kaisha | Automatic lateral guidance control system |
| DE69130147T2 (en) * | 1990-10-03 | 1999-04-01 | Aisin Seiki | Automatic control system for lateral guidance |
| US6145784A (en) * | 1997-08-27 | 2000-11-14 | Trw Inc. | Shared aperture dichroic active tracker with background subtraction |
| US20030035178A1 (en) * | 2001-08-17 | 2003-02-20 | George Seaver | Solid-state system for tracking and regulating optical beams |
| US7236299B1 (en) * | 2006-04-11 | 2007-06-26 | Bae Systems Information And Electronic Systems Integration Inc. | Compact periscopic beam director |
| CN102323593B (en) * | 2011-08-24 | 2016-05-18 | 北京国科环宇空间技术有限公司 | The system of two-dimensional dynamic target capturing |
| US20160224842A1 (en) * | 2012-01-09 | 2016-08-04 | Rafael Advanced Defense Systems Ltd. | Method and apparatus for aerial surveillance and targeting |
| DE102013002853A1 (en) * | 2013-02-20 | 2014-08-21 | Fogtec Brandschutz Gmbh & Co. Kg | Fire fighting equipment for rail vehicles |
| CN104793334B (en) * | 2015-04-02 | 2017-03-01 | 同济大学 | A kind of coarse-fine coupling optical scanning means of cascade |
| US10215846B2 (en) * | 2015-11-20 | 2019-02-26 | Texas Instruments Incorporated | Compact chip scale LIDAR solution |
| CN112526539B (en) * | 2020-11-25 | 2023-08-01 | 中国人民解放军战略支援部队航天工程大学 | Target compound motion detection device based on multimode vortex light beam |
| CN112697091B (en) * | 2020-12-07 | 2022-10-18 | 武汉中观自动化科技有限公司 | Tracking scanning system, calibration method and measurement method of relay tracker |
-
1984
- 1984-11-09 US US06/669,912 patent/USH341H/en not_active Abandoned
-
1985
- 1985-06-26 CA CA000485428A patent/CA1234419A/en not_active Expired
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3579174A1 (en) | 2018-06-08 | 2019-12-11 | Hexagon Technology Center GmbH | Mobile vehicles in manufacturing |
| WO2019234249A1 (en) | 2018-06-08 | 2019-12-12 | Hexagon Technology Center Gmbh | Mobile vehicles in manufacturing |
| US11282013B2 (en) | 2018-06-08 | 2022-03-22 | Hexagon Technology Center Gmbh | Mobile vehicles in manufacturing |
| CN111694009A (en) * | 2020-05-07 | 2020-09-22 | 南昌大学 | Positioning system, method and device |
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| Publication number | Publication date |
|---|---|
| USH341H (en) | 1987-10-06 |
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