ERDI LDR25K1 1064nm Laser Target Designator with 25mJ Output for Precision Target Marking

Control Functions

• Respond to ranging commands; stop upon stop command;
• Output one set of range data and status per pulse during ranging;
• Range gate function for ranging;
• Auto‑stop continuous ranging after 5 min (1 Hz) or 1 min (5 Hz) if no stop command is received;
• Configure designation mode and code;
• Respond to designation command per configured mode/code; stop upon stop command;
• Auto‑stop after one designation cycle if no stop command is received;
• Output distance and status per pulse during designation;
• Power‑on and periodic self‑test with status output;
• Respond to self‑test command with status output;
• Report cumulative number of emitted laser pulses.

TECHNICAL SPECIFICATIONS

OUTLINE DIMENSION

≤ 68 mm × 52 mm × 90 mm

PIN INTERFACE

Communication interface: one TTL-level serial port.
Connector model and interface definition: see Table 1.

Socket: MOLEX 53048-0810
Mating Plug: MOLEX 51021-0800

Table 1 — Electrical Interface Definition (TTL)

LDR25K1 1064nm 25 mJ Laser Rangefinder & Target Designator

The ERDI LDR25K1 is a solid-state 1064 nm laser rangefinder and target designator that combines precision ranging and coded laser marking in a compact module. With 25 mJ pulse energy and excellent beam quality, it is engineered for long-range target marking, survey calibration and cooperative engagement in modern ISR and fire-control systems. The module is suitable for UAV payloads, vehicle turrets, airborne pods and man-portable systems, where stable pointing, reliable coding and simple integration are critical.

At the laser level, the LDR25K1 uses LD-pumped solid-state technology at 1.064 μm, delivering ≥ 25 mJ pulse energy with pulse width around 15 ns. Beam divergence is kept to ≤ 0.5 mrad with optical-axis stability better than 0.05 mrad, and the divergence can be customized in the 0.3–1 mrad range to match different apertures and spot-size requirements.  The module supports ranging frequencies from single-shot and low-rate tracking at 1 or 5 Hz up to 20 Hz for fast update applications. Typical performance includes a minimum range around 120 m, a maximum range of at least 5 km on vehicle-sized NATO targets, ±2 m accuracy and a successful acquisition rate of ≥ 98%, with selectable first-target or last-target logic for cluttered scenes. 

In designation mode, the LDR25K1 provides a fundamental target designation frequency of 20 Hz, a coding accuracy on the order of 1 μs and an effective laser irradiation distance of ≥ 2 km. It supports both short-cycle and long-cycle operating profiles: short cycles offer tens of seconds of continuous designation with controlled intervals for up to eight cycles, while long cycles extend the single-cycle duration and support repeated operation with defined cool-down periods to protect the laser head. Built-in precise frequency coding with sixteen code positions, eight of which can be user-programmed, allows the system to match the timing requirements of air-to-ground guided weapons and other cooperative platforms, and it can accept external synchronization signals for code control. 

Mechanically, the LDR25K1 keeps a tight SWaP envelope, with overall dimensions of approximately 68 × 52 × 90 mm and mass not exceeding 380 g, making it easy to fit into gimbals and compact electro-optical turrets. The module runs from a 20–28 V supply with typical average power consumption ≤ 55 W and peak power ≤ 100 W. All internal boards receive conformal coating “three-proof” treatment for protection against humidity, dust and corrosive environments. 

Control and data exchange are handled via an RS-422 serial interface at 115200 bps, using an asynchronous 8-N-1 format with LSB-first transmission and defined 9-pin power/communication connector assignments for 24 V input and differential Tx/Rx lines, plus a reserved external trigger input. Through this interface the host can issue commands for single and continuous ranging, short and long designation cycles, range-gate setting, code configuration, self-test and stop commands. The module returns one set of distance and status data per pulse during both ranging and designation, provides regular status frames in standby, and records cumulative laser pulse counts and internal temperature, simplifying long-term maintenance and life management. 

To support deployment on mobile platforms, the LDR25K1 is qualified for wide-temperature operation from roughly −40 °C to +55 °C, with extended storage range, and is tested against swept-sine vibration spectra representative of aircraft take-off/landing and vehicle transport (up to 2 g in multiple axes) as well as repeated shock loads of ≥ 10 g with millisecond-level sawtooth pulses.  This environmental robustness, combined with automatic power-on/periodic self-test and MIL-STD-810G-based design principles, gives system integrators a tactical-grade laser designator that can be dropped into demanding missions with minimal redesign effort.