Choose between 905 nm and 1535 nm laser rangefinder modules by comparing exact model records under their stated target conditions. Wavelength alone does not determine useful range, accuracy, eye safety or host compatibility. Evaluate the target, minimum distance, installed mass, electrical interface and power budget before requesting a sample.
Compare model specifications, not wavelength slogans
| Model / wavelength | Published range and conditions | Module mass | Serial interface | Supply | Published power |
|---|---|---|---|---|---|
| SPD1200N2 905 nm |
0.2–1,200 m; target and ambient conditions require confirmation | ≤ 5 g | UART-TTL | 3.3–5 V | Average ≈ 0.45 W · max ≤ 0.75 W |
| LRF3000A1 905 nm |
≥ 3,000 m @ 70% reflectivity, building target (clear weather, visibility ≥ 4 km) | 12 ± 0.5 g | UART (TTL 3.3 V) | DC 3.3–5 V | ≤1.8 W at +25 °C; check peak demand separately |
| LRF0306C 1535 nm |
≥ 4000m @60% Reflectivity, Building Target ≥3000m @30% Reflectivity, 2.3×2.3m Target ≥1500m @30% Reflectivity, 0.5×1.7m Target ≥800m @30% Reflectivity, 0.2×0.3m Target; visibility >8 km for these source test cases | ≤14 ±1 g (notation as printed in the module document) | UART(TTL 3.3V) | DC 3~5V | 5 V: ≤0.9 W at 1 Hz; <1.1 W at 3 Hz; peak ≤3W |
| LRF0815C 1535 nm |
≥8,000 m to a 2.3 m x 2.3 m target, 30% reflectance, visibility ≥10 km | ≤175 g | RS-422; TTL optional | 12 V DC | Average ≤2 W; peak ≤3 W at 10 Hz |
Read each range with its target conditions. Module mass excludes the host assembly. Average power does not define peak rail demand. Open the exact model for its controlled documents and interactive 3D view.
What the wavelength comparison must retain
| Decision | 905 nm examples | 1535 nm examples |
|---|---|---|
| Measurement distance | Use the N2 or A1 record and its target conditions. | Use the C-module record and its target size, reflectivity and visibility. |
| Serial interface | The listed examples use UART / TTL. | LRF0306C lists UART, TTL 3.3 V; LRF0815C lists RS-422 with TTL optional. |
| Laser safety | Check the exact model document and finished assembly. | Check the exact model document and finished assembly. |
| System fit | Confirm mass, supply, output timing and connector. | Confirm mass, supply, output timing and connector. |
Keep the comparison within the source conditions
Do not compare a building-target figure with a small or dark target as if the tests were equivalent. Do not use an emitter’s component table to specify a complete ranging module. Compare the 905 nm UART examples with the 1535 nm UAV payload examples against the same project brief.
Engineering and purchasing questions
Does 1535 nm always give a longer useful range than 905 nm?
Wavelength alone does not establish that. Useful range depends on the exact model, target and environment. Preserve each source’s target size, reflectivity and visibility when comparing a catalog distance, and evaluate the target your system must measure.
Does 1535 nm automatically mean eye-safe?
No. The LRF0306C, LRF0405C and LRF0815C module documents state Class I. These are manufacturer statements, not third-party test reports. Classification applies to the complete configuration; wavelength alone does not establish the accessible-emission class of your finished product.
Is an erbium-glass laser source a complete rangefinder?
No. A laser source is an emitter component. A complete ranging module has its own receiver, ranging electronics, interfaces and model specifications. The laser-source family and rangefinder family are separate product groups.
Where can I get a datasheet or serial driver?
Open technical downloads for the exact model, driver resources and the ErdiTech driver repository for supported protocol families. Confirm the module, firmware, connector and logic voltage before using a driver. Documentation availability does not establish flight-controller compatibility.
Request a sample or an engineering review
Send the model or application, target and distance, host interface and quantity. We confirm the delivered configuration, sample terms and lead time in writing. Email tommy@erdimail.com or use the existing inquiry form below.
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