ChemSight^TM

The ChemSight™ detector is an infrared (IR), line of sight, sensing system for point of entry, fixed security, fence line and perimeter protection that utilizes a simple, non-contact, spectral analysis of the atmosphere. The use of optical line-of-sight detection and avoidance of direct contact with chemicals provides the following advantages unmatched by alternative, in-situ (or point) sensor technologies:

• Continuous, uninterrupted (24/7, 365 days/year), monitoring
  Immediate response (1 sec followed by 15 sec confirmation measurement)
• Long line monitoring (over 100m by a single detector) for the protection of large spaces, entry points, fence lines, perimeters of sporting events, etc.
• Multi-chemical detection (most chemical warfare agents, most important toxic industrial chemicals, and common interferant)
• Excellent background rejection capabilities (exhaust fumes, cleaning agents, fire extinguishing agents, water vapor, etc.)
• Digital chemical library updateable via internet.
• Long life, low maintenance (no contamination of sensing elements, filters, concentrators, etc.) and no consumables
• Built in proprietary confidence tester for remotely testing the detector to confirm operation, sensitivity and response time.

The system IR illuminator emits a collimated beam. Spectroscopic analysis of that beam is used to identify chemicals intercepting it anywhere along its path and to determine their optical density (CL – the product of the concentration and the linear dimension of the chemical cloud). The detector employs uncooled IR detectors. Eliminating the need for cryogenic refrigeration reduces the cost of the detector and complexity while rendering it robust. Chemicals are detected by comparing the detected signature with signatures stored in a digitally updatable chemical library. The extensive library includes signatures of high and medium priority threat chemicals and non-toxic inteferants thereby providing excellent background rejection capabilities.

The proprietary processing software was developed by Avir Sensors to correct for non-linear effects associated with strong absorptions. Therefore, the detector can provide detection at low levels of threat chemicals while the level of interferants is high. It also includes a threat evaluation logic that determines the risk level associated with each of the detectable chemicals and provides alarms accordingly.