The AFBR-S50 Integrated ToF Module

The AFBR-S50 is a high-end distance measurement sensor based on the indirect Time-of-Flight (iToF) principle. It packs everything needed for optical ranging into a single 12 × 12 × 8 mm module.

Inside each module, three core building blocks work together:

• Monolithic detector & driver ASIC — a single chip combining a 32-channel APD (avalanche photodiode) array, a reference pixel, the laser driver, and APD control and readout circuitry.
• VCSEL laser — the integrated light source that emits the measurement pulses.
• Housing & optics — separate transmit (Tx) and receive (Rx) lenses in a compact housing, mounted on a pinned PCB.

Because the detector and driver share one ASIC, the module stays small, light, and simple to integrate on a drone's flight controller or a dedicated sensor board.

Why ToF for Drones?

Drones demand sensors that are long-range, sunlight-proof, fast, and nearly weightless. The AFBR-S50 family was designed around exactly those constraints.

• 100 m+Long-range distance measurement
• 200 kluxAmbient light immunity — reliable in full direct sunlight
• 3 kHzHigh frame rate for fast, low-latency control loops
• 1 gCompact and lightweight — negligible payload impact
• Class 1Eye-safe laser operation
• Cortex M0Lean on compute — runs on a small microcontroller
• Non-ChinaManufactured outside China for supply-chain and compliance requirements

Typical ToF Use Cases for Drones

Three scenarios dominate drone ToF integration: altitude measurement, optical-flow-based visual navigation, and proximity triggering for interceptor drones.

Altitude Measurement

Direct altitude measurement in GPS-denied environments. Delivers reliable landing support and consistent height readings on all surface types — grass, concrete, water, snow, or dark asphalt.

Visual Navigation

Position hold and navigation in GPS-denied environments and indoors. The ToF sensor provides the accurate range input for optical-flow sensor fusion, anchoring the flow data to real-world scale.

Interceptor Trigger

A reliable trigger stage for counter-UAS interceptor drones, working as the final link in a layered sensing chain:

1. IR camera — identify the target
2. Radar — manage the approach
3. ToF — precise, hard-to-jam trigger at close range

ToF Product Portfolio

Seven AFBR-S50 variants span ranges from 5 m to over 100 m, with fields of view from a wide 12.4° × 5.4° down to a pencil-thin 0.4° × 0.4° beam. Drone-focused variants use narrow FoVs and long range; wide-FoV variants target mobile robotics and factory automation.

Design Resources for Drone Integration

From reference hardware to open-source drivers, the AFBR-S50 ecosystem is built for fast prototyping and production integration.

• Reference product — visual navigation Off-the-shelf visual navigation module by Ark Electronics, combining optical flow with AFBR-S50 ranging.
• Reference design — altitude measurement Altitude measurement reference design by MikroE for rapid hardware bring-up.
• Evaluation kit — AFBR-S50-FEK Family evaluation kit including a microcontroller board, all AFBR-S50 sensor variants, and a GUI for fast hands-on testing.
• Open-source API The AFBR-S50 API and driver core are available on GitHub, portable to Cortex-M-based microcontroller platforms.
• Flight-stack integration Integration, support, and drivers for PX4, ArduPilot, and ROS.
• Product family overview Full specifications, datasheets and modules available from EPS Global's Time-of-Flight 3D sensor range.