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Is an eye-safe Class 1 laser rangefinder module available as a component?

Accessible-emission limits at 1535 nm are far higher than at 905 nm because the cornea absorbs the beam before the retina, which is why the 1535 nm family can reach 3–23 km without exceeding Class 1 at the aperture. The class printed on a module applies to the module; the assembled product needs its own assessment.

Matching modules from the catalogue

Model	Wavelength	Published range	Accuracy	Mass	Interface
LRF1829C	1535 nm	23 km	±2 m	400 g	RS-422
LRF1830C	1.54 µm	23 km	±2 m	400 g	UART + RS-422
LRF1525C	1.54 µm	15 km	±2 m	400 g	RS-422
LRF1221C	1.54 µm	12 km	±2 m	275 g	RS-422
LRF1222C	1.54 µm	12 km	±2 m	335 g	RS-422
LRF1831C	1535 nm	12 km	±2 m	410 g	RS-422

The conditions behind those numbers

LRF1829C — a) Under line-of-sight conditions, with visibility not less than 26 km and humidity not greater than 50% (at 30 °C), the ranging distance for a vehicle target (3 m × 3 m) is ≥ 18,000 m. b) Under line-of-sight conditions, with visibility not less than 30 km and humidity not greater than 50% (at 30 °C), the ranging distance for a target with diffuse reflectance not less than 30% (6 m × 6 m) is ≥ 23,000 m.
LRF1830C — ≥23,000 m to a 6 × 6 m diffuse target, reflectance ≥30%; line of sight; visibility ≥30 km; relative humidity ≤50% at 30 °C
LRF1525C — 4m × 6m Objective ≥15 km
LRF1221C — 4m × 6m Objective ≥12 km
LRF1222C — Reference target(2.3m × 2.3m) ≥12 km
LRF1831C — a) Under line-of-sight conditions, with visibility not less than 15 km and humidity not greater than 80% (at 30 °C), the ranging distance for Target 1 (5 m × 15 m) is ≥ 6,500 m. b) Under line-of-sight conditions, with visibility not less than 15 km and humidity not greater than 80% (at 30 °C), the ranging distance for a target with diffuse reflectance not less than 30% (20 m × 20 m) is ≥ 12,000 m.

Full detail and the manufacturer's original wording: laser safety for integrators · all 59 range conditions · filter the catalogue yourself

Questions people ask about this

Can I rely on the module's Class 1 label?

For the module as supplied, yes as a starting point. Once you add optics, a window or a different housing the accessible emission changes and the classification must be reassessed.

Why is 1535 nm called eye safe?

Water in the cornea absorbs it, so the energy is deposited before the retina. The limit is on corneal exposure, which is much higher than the retinal limit that governs 905 nm.

What does the integrator still need to do?

Measure or calculate the accessible emission of the finished product, label it, and write the safety instructions. That responsibility does not transfer with the module.

Send the requirement, not a part number Target size, reflectance, required range, mass budget, interface, quantity. Two candidates and their limiting factor come back. Email tommy@erdimail.com All answers

Figures transcribed from manufacturer pages on 2026-10-24. Conditions are quoted verbatim; nothing here extrapolates a range to a target the manufacturer did not test.