<p>How does the Bambu Lidar work? I am convinced that Bambu is not using a Time-of-Flight Lidar method for its bed sensors. It might be a camera (or smart camera depending on your definition) that looks at an angled laser line aimed at the bed. The laser is offset from the camera and angled at 45 degrees. As the camera/laser approaches the bed, the position of the laser line shifts and appears as moving from one side of the camera's FOV to the opposite side. Given a known offset between the laser, camera, and nozzle, the height of the nozzle can be computed based on where the line is in the camera FOV.</p>
<p>The Bambu part for the Lidar seen at <a href="https://us.store.bambulab.com/products/bambu-micro-lidar-dual-red-laser-x1-series" rel="nofollow noreferrer">Bambu Micro Lidar (Dual Red Laser) - X1 Series</a> and <a href="https://wiki.bambulab.com/en/x1/manual/micro-lidar-model" rel="nofollow noreferrer">Bambu Lab micro lidar introduction and methods for distinguishing versions(single red or dual red)</a> looks very much like a regular CMOS sensor. The camera can also serve as a line width measurement tool in one of two ways. At a known FOV/magnification, the sensor pixels correlate to a known physical size and can measure width by edge detecting the contrast between material and the bed, this might be why it has some LED illuminators. Or it could also look at the laser line over the material as it would appear offset on the material as compared to the bed. (given a fine enough line)</p>
<p>If this is how it works, then I think the name is confusing and I think it is closer to structured light sensing. I'm also trying to understand the benefit of their later iterations with two lasers orthogonal to each other. Also, it would be worth duplicating this feature using an RP2040 with a camera like the <a href="https://www.waveshare.com/wiki/PICO-Cam-A" rel="nofollow noreferrer">PICO-Cam-A</a> and a laser line source. It seems like a basic bed probe replacement can be made with the RP2040 as a smart camera. Additional features could also be had when connected to a Raspberry Pi over USB for first-layer image analysis.</p>

CC BY-SA 4.0
2024-05-02T04:21:51.570Z
Don't know what Bambu is using. And, there are different types of LIDAR. Some use phase instead of directly measuring the time it takes light to travel. Finally, since these types of distance sensors are in most cell phones to prevent "cheek dialing", the price and size have dramatically decreased. So, is it some sort of LIDAR system?  Probably. Here's one you can try for your self for less than $20:  https://www.adafruit.com/product/5396
st2000
CC BY-SA 4.0
2024-05-03T15:39:59.463Z
Why are you convinced it's not a time of flight LIDAR?
Greg Miller
CC BY-SA 4.0
2024-05-07T01:47:26.560Z
@GregMiller The stated micrometer performance of their sensor is what peaked my initial interest, but I couldn't explain their design with the intent. A ToF measurement would require sub picosecond time resolution to get close to micron accuracy. Most commercial sensor need to be a single integrated emitter/sensor to control every part of the timing like the device st2000 posted. But the Bambu uses a separate laser that is mounted away from the sensor in a geometry that seems impossible to control precise timing. This level of sensor integration applies to phase detection too.
BrChan
<bed-leveling><calibration><laser>
Is the Bambu Lidar a structured light camera?
BrChan
# Is the Bambu Lidar a structured light camera?

(Asked by: username_0 on 2024-05-01)

How does the Bambu Lidar work? I am convinced that Bambu is not using a Time-of-Flight Lidar method for its bed sensors. It might be a camera (or smart camera depending on your definition) that looks at an angled laser line aimed at the bed. The laser is offset from the camera and angled at 45 degrees. As the camera/laser approaches the bed, the position of the laser line shifts and appears as moving from one side of the camera's FOV to the opposite side. Given a known offset between the laser, camera, and nozzle, the height of the nozzle can be computed based on where the line is in the camera FOV.

The Bambu part for the Lidar seen at [Bambu Micro Lidar (Dual Red Laser) - X1 Series](https://us.store.bambulab.com/products/bambu-micro-lidar-dual-red-laser-x1-series) and [Bambu Lab micro lidar introduction and methods for distinguishing versions(single red or dual red)](https://wiki.bambulab.com/en/x1/manual/micro-lidar-model) looks very much like a regular CMOS sensor. The camera can also serve as a line width measurement tool in one of two ways. At a known FOV/magnification, the sensor pixels correlate to a known physical size and can measure width by edge detecting the contrast between material and the bed, this might be why it has some LED illuminators. Or it could also look at the laser line over the material as it would appear offset on the material as compared to the bed. (given a fine enough line)

If this is how it works, then I think the name is confusing and I think it is closer to structured light sensing. I'm also trying to understand the benefit of their later iterations with two lasers orthogonal to each other. Also, it would be worth duplicating this feature using an RP2040 with a camera like the [PICO-Cam-A](https://www.waveshare.com/wiki/PICO-Cam-A) and a laser line source. It seems like a basic bed probe replacement can be made with the RP2040 as a smart camera. Additional features could also be had when connected to a Raspberry Pi over USB for first-layer image analysis.

**Tags:** bed-leveling, calibration, laser
> **Comments:**
> **username_1**: Don't know what Bambu is using. And, there are different types of LIDAR. Some use phase instead of directly measuring the time it takes light to travel. Finally, since these types of distance sensors are in most cell phones to prevent "cheek dialing", the price and size have dramatically decreased. So, is it some sort of LIDAR system?  Probably. Here's one you can try for your self for less than $20:  https://www.adafruit.com/product/5396  
> **username_2**: Why are you convinced it's not a time of flight LIDAR?  
> **username_0**: @GregMiller The stated micrometer performance of their sensor is what peaked my initial interest, but I couldn't explain their design with the intent. A ToF measurement would require sub picosecond time resolution to get close to micron accuracy. Most commercial sensor need to be a single integrated emitter/sensor to control every part of the timing like the device st2000 posted. But the Bambu uses a separate laser that is mounted away from the sensor in a geometry that seems impossible to control precise timing. This level of sensor integration applies to phase detection too.  

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## 0 answers

