# US 5,350,134 A · Target identification systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,350,134 A - Document ID: US5350134A - Status: Granted - Kind: A - Application number: 06/374,791 - Filed: 1973-07-03 - Granted: 1994-09-27 - Earliest claimed: 1973-07-03 - Assignees: GEC Ferranti Defence Systems Limited - Inventors: Ian D. Crawford - Web page: https://patentgrep.com/patent/US5350134A ## CPC - F41G 7/226: {Semi-active homing systems, i.e. comprising a receiver and involving auxiliary illuminating means, e.g. using auxiliary guiding missiles} - F41G 7/2293: {using electromagnetic waves other than radio waves} - F41G: WEAPON SIGHTS; AIMING (optical aspects thereof G02B) ## Abstract A target identification system includes a target marker for selecting, and directing radiation at, a target, a weapon delivery system, and means for establishing a two-way communication channel between the two by reflection from a selected target. The communication is by infra-red laser and coded information is sent between the target marker and the weapon delivery system to identify the selected target. ## Claims ### Claim 1 A target identification system which includes a target marker capable of selecting, and directing radiation at, a target, a weapon delivery system to which the target is to be identified, means for establishing between the target marker and the weapon delivery system a two-way communication channel over which pulsed radiation may be transmitted from one to the other by reflection from the selected target, and means carried by the target marker and the weapon delivery system for so encoding the radiation transmitted over the communication channel as to identify uniquely the selected target to the weapon delivery system. ### Claim 2 (depends on 1) A system as claimed in claim 1 in which the target marker includes a laser operable to transmit radiation towards the target and a radiation-sensitive detector operable to receive laser radiation reflected from the target. ### Claim 3 (depends on 2) A system as claimed in claim 2 in which the radiation-sensitive detector carried by the target marker is provided with an optical system having an optical axis parallel to that of the laser carried by the target marker. ### Claim 4 (depends on 1) A system as claimed in claim 1 in which the weapon delivery system includes a laser operable to transmit radiation towards the target and a radiation-sensitive detector operable to receive laser radiation reflected from the target. ### Claim 5 (depends on 4) A system as claimed in claim 4 in which the radiation-sensitive detector carried by the weapon delivery system is provided with an optical system having an optical axis parallel to that of the laser carried by the weapon delivery system. ### Claim 6 (depends on 5) A system as claimed in claim 5 in which the radiation-sensitive detector carried by the weapon delivery system is sensitive to the direction of incidence of radiation falling upon it. ### Claim 7 (depends on 4) A system as claimed in claim 4 in which the weapon delivery system includes means operable to prevent the transmission of radiation by its laser except when the optical axis of the laser is directed towards an apparent source of radiation. ### Claim 8 (depends on 1) A system as claimed in claim 1 in which the encoding means carried by the target marker includes means for causing the laser carried thereby to emit a train of pulses of radiation at a predetermined repetition rate until a pulse of radiation is received by its radiation-sensitive device. ### Claim 9 (depends on 8) A system as claimed in claim 8 in which the encoding means carried by the target marker also includes means responsive to a received pulse of radiation to transmit a single pulse of radiation after a preset delay. ### Claim 10 (depends on 1) A system as claimed in claim 1 in which the encoding means carried by the target marker includes means for determining the range of the target from the target marker. ### Claim 11 (depends on 1) A system as claimed in claim 1 in which the encoding means carried by the weapon delivery system includes means responsive to the detection of a train of pulses of radiation having a predetermined repetition rate to generate a train of gating pulses. ### Claim 12 (depends on 11) A system as claimed in claim 11 in which the encoding means carried by the weapon delivery system also includes means responsive to a required number of coincidences between gating pulses and detected pulses of radiation to cause the laser to emit a single pulse of radiation. ### Claim 13 (depends on 1) A system as claimed in claim 1 in which the encoding means carried by the weapon delivery system includes means for determining the range of the target from the weapon delivery system. ### Claim 14 (depends on 2) A system as claimed in claim 2 in which the laser is operable to emit pulses of intra-red radiation. ### Claim 15 (depends on 14) A system as claimed in claim 14 in which the laser is a Q-switched device. ### Claim 16 (depends on 1) A target marker for a target identification system as claimed in claim 1 which includes a laser operable to transmit radiation towards the target and a radiation-sensitive detector operable to receive laser radiation reflected from the target. ### Claim 17 (depends on 16) A target marker as claimed in claim 16 in which the encoding means includes means for causing the laser to emit a train of pulses of radiation at a predetermined repetition rate until a pulse of radiation is received by its radiation-sensitive detector. ### Claim 18 (depends on 17) A target market as claimed in claim 17 in which the encoding means also includes means responsive to a received pulse of radiation to transmit a single pulse of radiation after a preset time delay. ### Claim 19 (depends on 16) A target marker as claimed in claim 16 which includes means for determining the range of the target from the target marker. ### Claim 20 (depends on 1) A weapon delivery system for a target identification system as claimed in claim 1 which includes a laser operable to transmit radiation towards the target and a radiation-sensitive detector operable to receive laser radiation reflected from the target. ### Claim 21 (depends on 20) A weapon delivery system as claimed in claim 20 in which the radiation-sensitive detector is sensitive to the direction of incidence of radiation falling upon it. ### Claim 22 (depends on 21) A weapon delivery system as claimed in claim 21 in which the encoding means includes means responsive to the detection of a train of pulses of radiation having a predetermined repetition rate to generate a train of gating pulses. ### Claim 23 (depends on 22) A weapon delivery system as claimed in claim 22 in which the encoding means also includes means responsive to a required number of coincidences between gating pulses and detected pulses of radiation to cause the laser to emit a single pulse of radiation. ### Claim 24 (depends on 20) A weapon delivery system as claimed in claim 20 in which the encoding means includes means for determining the range of the target from the weapon delivery system. ### Claim 25 (depends on 4) A system as claimed in claim 4 in which the laser is operable to emit pulses of infra-red radiation. ### Claim 26 (depends on 25) A system as claimed in claim 25 in which the laser is a Q-switched device.