Zoom Thermal Imaging Camera Module

Motorised Optical Zoom — What Variable Focal Length Enables

All other modules in the standard LWIR OEM range use fixed focal length lenses — the field of view is set at installation and does not change during operation. The zoom module uses a continuous motorised zoom lens that adjusts focal length from 35 mm to 105 mm (3× magnification range) under remote electronic control via the RS485 PELCO-D interface or Ethernet commands. This variable focal length capability enables two distinct operational modes from a single installed camera: wide-angle mode (35 mm, ~18° horizontal FOV) for area surveillance — monitoring a large scene to detect the presence and general position of thermal targets; and narrow-angle mode (105 mm, ~5.9° horizontal FOV) for long-range detail — magnifying a specific detected target to confirm its identity, nature, and precise position. The continuous zoom between these extremes allows the operator to follow a moving target at any detection range while maintaining the optimal fill factor (target size relative to frame size) for identification.

35–105 mm Focal Length — Detection Range at Each End

The detection range at which a given target size fills a useful fraction of the 640×480 sensor frame scales directly with focal length. At 35 mm (wide), the ~18° horizontal FOV covers approximately 315 m width at 1 km distance — a single standing person (shoulder width ~0.5 m) occupies approximately 1–2 pixels of the 640-pixel-wide frame, enabling area detection but not identification. At 105 mm (narrow), the ~5.9° FOV covers approximately 103 m width at 1 km — the same person now occupies approximately 3–6 pixels, providing better thermal signature definition for identification purposes. For a helicopter-sized airborne target (rotor span ~10 m) at 3 km, the 105 mm setting fills approximately 30 pixels — sufficient for thermal signature characterisation. These are indicative figures; the DRIM (Detection, Recognition, Identification) ranges for specific target sizes should be calculated using the Johnson Criteria methodology for each application during system design.

Motorised 3× Optical Zoom — Unique in the Standard Module Range

The 35–105 mm motorised optical zoom provides 3× continuous magnification range, enabling remote transition between ~18° wide-area surveillance and ~5.9° long-range narrow-angle detection without touching the camera. No other standard LWIR OEM module in the range offers variable focal length — this is the zoom module’s defining and exclusive capability.

High Thermal Sensitivity — <30 mK Option

The <30 mK NETD option (alongside the <50 mK tier) provides the highest sensitivity available, enabling reliable detection of subtle thermal differences at long range where the target’s thermal contrast against background is reduced by distance-related effects. High sensitivity combined with the telephoto zoom capability is the combination that enables long-range thermal detection and classification.

RS485 PELCO-D Zoom Control — VMS and Joystick Compatible

PELCO-D protocol over RS485 enables motorised zoom control from any PTZ joystick controller or VMS platform that supports PELCO-D — the dominant PTZ control standard in the global security industry. No custom control software is required; the thermal zoom integrates into existing PTZ control infrastructure immediately.

ONVIF + Ethernet PoE Network Integration

ONVIF-compliant Ethernet streaming enables the thermal zoom module’s video to be received by any ONVIF VMS or NVR platform alongside visible-light IP cameras without custom integration. PoE delivers power over the same Ethernet cable, simplifying installation at remote outdoor mounting positions.

Digital I/O for Security System Integration

Digital I/O alarm output connects to security alarm panels, PLCs, and automation systems to signal thermal detection events. External trigger input enables automated zoom responses to motion detection signals, access control events, or other alarm triggers from the wider security system.

IP67 Front Lens and Rugged Body for Outdoor Deployment

IP67-rated front lens and rugged enclosure enable deployment in outdoor perimeter security, maritime, and harsh industrial environments exposed to rain, dust, humidity, and temperature extremes. Sub-5-second startup ensures rapid thermal readiness after power cycling in outdoor installations.

Security and Surveillance

Motorised zoom enables dynamic field-of-view adaptation for perimeter monitoring, border surveillance, and critical infrastructure protection:

• Perimeter security with zoom-on-demand: thermal camera in wide mode surveying a long perimeter fence line detects a thermal intrusion signature, then operator zooms to 105 mm narrow angle to examine the detection at range without physically redirecting the camera or dispatching a security officer for initial confirmation
• Critical infrastructure surveillance: zoom thermal monitoring of power substations, refineries, airports, and data centre perimeters — wide angle for area situational awareness, narrow zoom for detailed examination of specific anomalies or personnel detected at range
• Border and coastal surveillance: long-range thermal detection of cross-border movement and coastal approaches — wide mode detects thermal presence; narrow zoom confirms identity and direction of movement at distances where standard fixed-lens cameras provide insufficient detail

Industrial Monitoring and Preventive Maintenance

Remote zoom capability enables thermal inspection of distant or inaccessible industrial equipment without repositioning or physical access:

• Large facility thermal survey: motorised zoom thermal camera mounted at an elevated position surveys a large industrial plant — wide angle for systematic facility thermal overview, narrow zoom for examination of specific equipment identified as anomalous in the wide view, without requiring the camera or operator to move to a closer position
• High-voltage equipment inspection: zoom thermal monitoring of HV transmission line hardware and substation equipment from safe standoff distance, zooming in on specific conductor clamps or insulators identified as thermal anomalies in the wide surveillance view
• Remote equipment monitoring: fixed zoom thermal camera monitoring equipment in hazardous areas (chemical plants, high-temperature process zones) that cannot be accessed during operation, with remote zoom control for detailed examination of thermal anomalies identified in the wide monitoring view

Unmanned Systems — UAV and UGV

Motorised zoom provides on-demand magnification during drone and robot missions where target distance changes continuously:

• UAV reconnaissance and surveillance: zoom thermal drone payload enabling the operator to switch between wide-area thermal survey mode and narrow-angle target examination mode during flight without changing the UAV’s altitude or position — the zoom replaces the altitude change as the means of obtaining more detail
• UGV inspection at variable distances: ground robot with zoom thermal camera approaching an inspection target uses wide angle for navigation and initial detection, then zooms in for detailed thermal examination of the target component before physical intervention
• Search and rescue aerial operations: zoom thermal UAV payload in wide mode detects survivor thermal signatures over a large search area, then zooms to narrow for confirmation and precise GPS location before dispatching ground teams

Maritime and Marine Operations

Long-range zoom capability and IP67 protection serve maritime navigation, vessel surveillance, and offshore security:

• Vessel approach detection: zoom thermal camera on harbour entrance or vessel bridge detects approaching traffic in wide mode at long range, then zooms to examine vessel type, heading, and crew presence for maritime domain awareness and collision avoidance
• Offshore platform perimeter security: IP67 zoom thermal cameras on offshore oil and gas platforms monitoring the sea surface in wide mode for vessel approach detection, with zoom capability for detailed examination of small boat contacts at range
• Port and harbour surveillance: zoom thermal cameras at port approach points covering a wide harbour entrance in surveillance mode, zooming to examine specific vessels, floating objects, or personnel detected at range for port security management

Defence and Tactical Applications

Sensitivity, zoom range, and PELCO-D integration make the module suitable for defence surveillance and reconnaissance systems:

• Fixed site surveillance: zoom thermal cameras at defended positions covering wide approach sectors with thermal detection capability and zoom-on-demand for target identification at range, integrated with existing PELCO-D joystick control stations at the operator position
• Vehicle-mounted thermal surveillance: zoom thermal module on armoured vehicle or observation post providing the crew with wide-area thermal awareness and on-demand zoom for identification of thermal contacts without exposing personnel or repositioning the vehicle
• Force protection: zoom thermal monitoring of base perimeters and approach routes — wide mode for continuous perimeter surveillance, zoom for confirmation and identification of detected thermal contacts before escalation of force protection response

Smart Infrastructure and Urban Monitoring

Zoom thermal modules integrate with smart city and urban monitoring networks for traffic, safety, and emergency management:

• Traffic junction thermal monitoring: zoom thermal camera at a major intersection monitors traffic flow in wide mode and zooms to examine specific vehicles or incidents identified as anomalous for traffic management and accident detection
• Smart city perimeter monitoring: ONVIF-integrated zoom thermal cameras in smart city surveillance networks providing thermal detection capability with VMS-controlled zoom for multi-agency situational awareness during public events and emergencies
• Industrial estate and infrastructure monitoring: zoom thermal cameras integrated with urban infrastructure monitoring platforms providing wide-area thermal surveillance with zoom capability for detailed anomaly investigation without deploying inspection personnel

United Spectrum Instruments delivers advanced thermal imaging solutions with expert support and seamless integration services across India. From product selection and system design to installation, networking setup, and after-sales assistance, USI ensures the zoom thermal module performs optimally in security, industrial, UAV, maritime, and defence applications.

Expert Integration Support for Zoom, PTZ, and Network Systems

RS485 PELCO-D configuration for VMS and joystick control system integration, ONVIF network setup for VMS/NVR platform integration, Digital I/O alarm wiring, PoE network design, and application-specific zoom range usage guidance for detection and identification range planning.

Application Expertise Across Security, Defence, UAV, and Maritime Verticals

Application-specific consultation for perimeter security system design with zoom thermal cameras, UAV payload integration, maritime surveillance system design, and defence site protection thermal monitoring — the primary application domains for the motorised zoom module.