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Laser Listening System

Laser Listening System "Laser Ear"
Description

 LALS

The “Laser Ear” is a long range, State of the Art, highly directional microphone specially developed for Governments and their Law Enforcement organizations, to be used covertly in situations when entrance is not suitable for placing a listening device into the targeted room. It allows the operator to carry out undetectable, long range surveillance from the outside of the building.

The “Laser Ear” consists of three parts:

  • Laser Transmitter
  • Laser Receiver
  • Amplifier Unit with Audio-Recorder

This system is operated by transmitting an invisible IR (Infra-red) beam to the window of the target room. It picks up the vibration of the window pain, according to the sound waves emanating from speech, bounces it back to the Laser Optical Receiver where the modulated beam is synonymously converted into electronic signals, which are then interpreted back into audible voice, amplified and fed into a professional UHER recorder. The complete system is supplied in large water proof transportable camera case, including the amplifier, the filters and the recorder. It transmits and records sound wave vibrations, reflected of smooth surface of the glass (single or double thermo pane). Rippled or grained glass will not provide a suitable reflecting surface and in most cases it will not work. However, acoustic interferences caused by interior or exterior sound wave reflections may be filtered and modulated trough the Lasers Optical Receiver. The transmission may be also fine tuned by modulating the search tone or by changing the placement of the receiver itself.

Technical Specifications:

Laser Transmitter

  • Laser Type: Semi-conductor Laser
  • Wave Length: 750 - 840 nm
  • Output Power: 5 mW automatically controlled
  • Power Supply: 8 x 1.5 V AAA Battery (extern)
  • Current Consumption: approx. 100 mA
  • Beam Focusing: 135 mm
  • Target Finder: through lens
  • Connections: 1 for power supply
  • Mounting: standard to fit to the tripod
  • Operating Time: approx. 10 hours continuous
  • Other features: switchable modulation, search tone

Laser Receiver

  • Laser Type: noiseless PIN-Diode
  • Wave Length: Infrared
  • Lens: 500 mm
  • Power Supply: 9 V Block Battery
  • Battery Life: 15-50 hours (depending on the adjusted volume)
  • Current Consumption: 10 - 30 mA

Amplifier

  • Amplifier unit: connected by cable with Laser Receiver
  • Amplification: adjustable
  • Connections: Headphone, Speaker
  • Voice Filter: Equaliser, adjustable
  • Voice Recorder: built-in and internally connected with the amplifier

Mechanical

  • Dimensions: 470 x 380 x 220mm
  • Weight: 10.5 kg without batteries and tripods