LRF1829C 18–23km 1535nm Eye-Safe Ultra Long-Range Laser Rangefinder Module for Coastal, Border and Strategic EO/IR Systems

TECHNICAL SPECIFICATIONS

OUTLINE DIMENSION(mm)

125×100×72mm

PIN INTERFACE

Selectable between TTL (Molex 51021-0500) / RS-422 (J30J)

1 Electrical connector model: Molex51021-0500. The detailed definition of the electrical interface is as follows:

Table 1 Interface definition

4.2. Electrical connector model: J30J; The corresponding plug and cable shall be provided by Party B. The detailed definition of the electrical interface is shown in the following table:

Interface Definition

Product Description

LRF1829C 18–23km 1535nm Eye-Safe Ultra Long-Range Laser Rangefinder Module for Coastal, Border and Strategic EO/IR Systems

The LRF1829C is a high-performance, ultra long-range laser rangefinder module based on a 1535nm eye-safe glass laser independently developed by ERDI. Using a single-pulse time-of-flight (TOF) measurement principle, it is designed as an OEM core for coastal and border surveillance, strategic EO/IR systems, vehicle and naval fire-control aids and long-range reconnaissance payloads where 18–23km-class performance is required in a compact, integration-ready form.

The module operates at 1535nm±0.005µm, Class I eye-safe, with a divergence angle of ≤0.3mrad, single-pulse energy ≥500µJ, a Φ18mm launch lens and a Φ60mm receiver lens. Under 30% reflectance and line-of-sight conditions, the LRF1829C provides a vehicle target (3m×3m) measuring distance of ≥18,000m with visibility not less than 26km and humidity not greater than 50% at 30°C. For a diffuse target (6m×6m, reflectance ≥30%), with visibility not less than 30km and humidity not greater than 50% at 30°C, the measuring range reaches ≥23,000m. The minimum range is ≤50m, ranging accuracy is ±2m, range resolution ≤0.1m, precision rate ≥98% and false alarm rate ≤1%, enabling reliable distance data across the full span from near field to tens of kilometres.

The LRF1829C supports a ranging frequency from 0.5Hz to 10Hz, allowing slow update rates for persistent surveillance or higher refresh rates for tracking and cueing tasks. Multi-target detection is supported, with up to three targets per shot reported from near to far. In both single and continuous ranging modes, the range data frame includes three distance values (0.1m resolution) and a flag byte that indicates main-wave and echo presence, laser status, timeout, APD status and whether fore and aft targets exist. This allows system designers to implement first/last target logic and advanced filters in complex environments such as layered coastlines, harbor areas, mountain ridges and urban skylines.

Electrically, the module is powered from DC 12V. Standby power consumption is ≤1.2W, average power ≤2W and peak power ≤3W, offering a balanced power profile for tower, vehicle, shipborne and fixed EO/IR installations. A pin-in-lead J30J package provides an RS-422 differential interface with RX+/RX− and TX+/TX− lines and multiple supply pins. Alternatively, a Molex 51021-0500 connector exposes a TTL (3.3V) interface with RX, TX, CTRL (3.3–5V power-on, 0V power-off), +12V and GND. This dual-interface approach lets integrators choose short-run TTL wiring inside instruments or RS-422 for longer cable runs in noisy environments. Communication format is master–slave, 115200bps, 8 data bits, one start bit, one stop bit and no parity.

Command frames begin with a 0x55 start flag, followed by a command word, data length, parameter bytes and an XOR checksum. Core commands include standby (continuous ranging stop), single ranging, continuous ranging with a programmable period in milliseconds, self-test, distance selection and minimum distance (blind-zone) setting, cumulative laser-shot query, APD power on/off and serial-number query. Response frames carry self-test values such as APD temperature, APD high voltage and internal voltages, blind-zone distance, total shot counts, up to three target distances and a detailed status flag byte. These diagnostics make it straightforward to monitor health, manage life usage and optimise algorithms in demanding long-range applications.

Mechanically, the LRF1829C is housed in a 125×100×72mm module with a weight of ≤400g, using a pin-in-lead package for robust mounting in turrets, masts and fixed stations. It is specified for an operating temperature range of −40 to +70°C, storage from −55 to +75°C, and meets MIL-STD-810G impact and vibration test standards, ensuring long-term reliability on border towers, coastal sites, armored vehicles and naval platforms exposed to harsh mechanical and climatic conditions.

For installations with an external optical window—such as sealed EO/IR heads, coastal domes or long-range camera housings—the optical window should be coated with an anti-reflective (AR) coating optimized for 1525–1545nm with transmittance ≥99%. Depending on the environment, additional hydrophobic or hard coatings can be applied, with overall transmittance maintained at ≥97%. Window geometry should follow the recommended guidelines: effective aperture at least 2mm smaller than the outer diameter, antenna clearance ≥1.5mm, thickness typically 2–4mm, emission axis aligned within 2–4° of the window normal and the air gap kept as small as possible to limit absorption and back-reflection.

In real deployments, an ultra long-range 1535nm eye-safe module like the LRF1829C is suited for coastal and border surveillance networks, strategic EO/IR and thermal imaging systems, long-range reconnaissance cameras, vehicle and shipborne observation posts, over-the-horizon cueing sensors and industrial distance-measurement setups where 18–23km-class performance, Class I eye safety and a straightforward UART/RS-422 interface are all critical.