what matters in lidar? · • what customers actually/practically want is a lidar with no gaps...

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What Matters in LIDAR?• Performance

• Range

• Angular Resolution (horizontal, vertical)

• Field of View (horizontal, vertical)

• Scan rate/frame rate (per second, in Hz)

• Range repeatability (range “noise”)

• Power consumption

• Spatial resolution

• Spatial accuracy - any “blooming”, artifacts, etc(How accurately you measure the location you think the lidar is pointing in)

• Environmental variability (e.g., over broad temperatures, in high humidity, peak sun, inclement weather)

• Other features (e.g., color, multiple returns, region of interest)

• Price

• Form Factor

• Size

• Mass

• Quality/Reliability

• Automotive Spec

• Ingress

• Shock/Vibe/Jitter

• Thermal Range & Cycling

• Corrosion

• Scalability/Availability

• Product or PowerPoint Slide?

• Manufacturability

• Consumer owned vehicle or Robotaxi


Automotive Performance Req’s (1/2)• Range

• >200m @ 10% reflectivity for a normally oriented lambertian target

• Companies can play a lot of games on how to report range, generally one needs to know range with the following qualifiers:

• Reflectivity of target (e.g., 10%, 50%, 80%)

• Type and orientation of the target (e.g., normally oriented, lambertian target)

• Sunlight intensity (e.g., 225 w/m2, 1,000 w/m2)

• How the lidar signal processing is tuned. For instance, what is the false positive detection rate of the sensor (e.g. ~1/1000)? It is possible to see farther if the lidar is allowed to output more false positives.

• Achieving 200 meters @ 10% is difficult and typically comes with field of view, resolution, cost, and power tradeoffs.

• Angular Resolution:

• 0.1 degrees by 0.1 degrees - 100 measurements per 1 degree by 1 degree segment.

• What customers actually/practically want is a lidar with no gaps between LIDAR points and sufficient resolution to resolve objects at 200 meter range. Depending on the LIDAR this may be slightly different from 0.1 degree x 0.1 degree resolution.

• Field of View:

• 40 degrees vertical, 120 degrees horizontal (with angular resolution above)

• Combined with the 0.1° angular resolution requirement, this means, 400 points vertically by 1,200 points horizontally -480,000 data points per scan

• Scan rate (frame rate) of >20 Hz

• At 20 Hz x 480,000 data points = 9.6 million points per second

• Today, almost all sensors run at 10 Hz

• Range repeatability of < 5cm


Automotive Performance Req’s (2/2)• Power consumption of < 10 watts

• Power consumption over 20 watts is simply a non-starter for an automotive company and the expectation is about half that. Many, many performance issues with all kinds of products can be solved temporarily by pursuing solutions that consume more power. Your phone could be twice as fast with a more powerful processor, but it would have half the battery life, and your car could contain a 100 watt lidar system and see 300 meters tomorrow, but it would cost more than the car itself and overheat in Arizona summers.

• True technological breakthroughs come when the technology enables improvements on many fronts at once, and power efficiency is one of those fronts.

• Environmental variability - difficult to spec, but needs to perform well in high humidity, hot, sunny environments as well as in below freezing cold winter conditions).

• For example, Ouster’s LIDAR operates at 850 nm wavelength where atmospheric water absorption is orders of magnitude lower than at 905nm, 940nm, or 1550 nm. This allows it to operate more effectively in highly humid environments. Most LIDAR companies are located in arid regions (Israel, California) and haven’t done significant testing in cold weather, humid weather, or where fog, rain, snow, sleet, and hail are common.


Other thoughts• Customer deployments are the ultimate validation

for LIDAR maker claims

• Beware of “Cherry Picking” and not reporting on performance on all dimensions at once


Technology approaches• Discrete or Semiconductor

• If semiconductor, Silicon CMOS or InGaAs?

• Scanning mechanism• Flash

• MEMS

• Galvo/Macro-mirror

• Rotation

• Other (e.g., OPA, LWIR)

• Laser type – NIR, 1550nm // Pulsed, FMCW, other


Testing LIDAR companies• Live demos, outdoors in sunlight.

• Lengthy sample data, outdoors

• Is the functioning demo unit being shown the final form factor?

• Datasheet/Spec• Every real product has a datasheet. Does the company in question have a datasheet? Are

they willing to share it with you? If not, why not? • Verify the form factor / mass against target customer specs - e.g., 6cmx8cmx8cm / <500g.• Check the datasheet power draw. Is it around 10 watts or significantly more?• Ask if the system that is generating their demos or posted data demonstrations is the same

device they are demonstrating for their form factor.

• Price• Show proof that they are selling at reasonable prices and/or have reasonable costs. • If they won’t share pricing, why not? Do they avoid the question by focusing on how cheap

their product will be in the future?

• Scalability/availability• Hard to judge, but can someone buy their sensor if they want it? What is the lead time?

Has someone bought 1? 10? 100?• Number of customers

what matters in lidar? · • what customers actually/practically want is a lidar with no gaps...

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