ERDI LASER
High-Repetition 1535nm Laser Source, 500Hz to 5kHz
What "high repetition rate" changes Repeating a pulse faster does not simply multiply the output. Each shot deposits pump energy in the same small crystal, and the heat has to leave before the next one arrives. At 1–10 Hz the thermal problem is trivial and the design is free to maximise energy per pulse; from 500
What "high repetition rate" changes
Repeating a pulse faster does not simply multiply the output. Each shot deposits pump energy in the same small crystal, and the heat has to leave before the next one arrives. At 1–10 Hz the thermal problem is trivial and the design is free to maximise energy per pulse; from 500 Hz to 5 kHz the design is constrained by average power, and energy per pulse has to come down to keep the crystal inside its thermal envelope.
That is the whole reason a separate high-repetition family exists. The four models below are not scaled-down versions of the millijoule units — they are a different point on the same trade curve.
The four kHz models
| Model | Pulse energy | Repetition rate | Average power | Pulse width | Weight | Supply / peak current | Rated life |
|---|---|---|---|---|---|---|---|
| ER10 | ≥10 µJ | 5 kHz | 50 mW | 5 ns | 6 g | 2 V / 5 A | ≥5 million shots |
| ER20 | ≥20 µJ | 2.5 kHz | 50 mW | 5 ns | 6 g | 2 V / 5 A | ≥5 million shots |
| ER40 | ≥40 µJ | 1 kHz | 40 mW | 4 ns | 6 g | 2 V / 5 A | ≥5 million shots |
| ER70 | ≥70 µJ | 500 Hz | 35 mW | 4 ns | 6 g | 2 V / 5 A | ≥5 million shots |
Average power is the product of the first two columns, calculated from the published minimums. It stays within 35–50 mW across all four, which tells you what the package is really rated for: the same 6 g housing, the same 2 V / 5 A drive and the same 4–5 ns pulse, with the energy–rate pair placed wherever the application needs it.
Choosing a point on the ladder
The four models differ only in that pair, so the question is which one the system is short of:
- Points per second — a scanner that needs dense angular coverage takes ER10 at 5 kHz and accepts 10 µJ per shot.
- Energy per shot — a system measuring through a worse link takes ER70 at 500 Hz and accepts a tenth of the point rate.
- In between — ER20 and ER40 are the two intermediate points, at 2.5 kHz and 1 kHz.
If the requirement needs more than 70 µJ per pulse, the kHz family is the wrong family. The next step up is the 1–10 Hz compact range (100 µJ to 900 µJ), and above that the millijoule transmitters. Choosing across families is covered on the LiDAR page.
Rated life is counted in shots, not hours
All four kHz models are rated for at least 5 million shots. Converted at the rated repetition rate, that is roughly 17 minutes of continuous firing at 5 kHz, 33 minutes at 2.5 kHz, 83 minutes at 1 kHz and about 2.8 hours at 500 Hz. The compact 1–10 Hz models are rated in the same unit at a far lower rate, which is why the same arithmetic gives them roughly 28–280 hours of continuous operation.
The rated life is a minimum, and it is quoted without its test condition. If the application runs the laser near its rated rate for long periods, ask for the energy and duty cycle at which the figure was measured — a lifetime number taken at reduced energy does not transfer to full-energy operation.
Drive, trigger and timing
These models are pumped by a short, high-current pulse from a 2 V rail at 5 A peak, and they are triggered externally at the repetition rate the system chooses. Two consequences matter at kHz rates:
- The trigger is the clock. Range accuracy in a scanning system depends on knowing when each pulse left, so trigger-to-optical-output delay and its variation across units have to be characterised, not assumed.
- Pulse-to-pulse stability is a thermal property. A unit that has just been switched on and one that has been running at 5 kHz for ten minutes are at different crystal temperatures; the first pulses after a cold start are not representative. Allow warm-up before measuring energy or timing.
Interface details per model are in the datasheets on the engineering centre page.
Where the kHz family is used
Scanning LiDAR, gated imaging, range-gated sensors, and any design that trades energy per pulse for update rate. The common thread is that many measurements are averaged or fused, so a single weak return is not the limiting case — which is exactly the condition under which a 10 µJ pulse at 5 kHz outperforms a 200 µJ pulse at 10 Hz.
If the system has to work from a single shot against an uncooperative target, the trade reverses and the millijoule models are the starting point. The rangefinder page covers that selection path.
Narrowing it down
Send the repetition rate the system needs, the energy per pulse the link budget requires, and the supply available. With those three the model is determined; without them the answer is a range rather than a part number. The RFQ guide lists what else is worth including.
Send the requirement · Compare all 1535 nm models · How the 1535 nm source works