What is the maximum detection distance of the VL53L7CX for a black object?

[SY_HONG]

Hi,

I am using the VL53L7CX in an object detection system.

Today, I found that the sensor does not detect black objects well. It can only detect a black object at a very short distance, approximately 10 cm.

Is this the expected behavior?

If so, what is the maximum detection distance of the VL53L8CX for a black object?

My application requires the sensor to reliably detect a black object at a distance of about 50 cm.

Is there any way to improve the detection performance for black objects, such as changing the configuration or tuning any parameters?

Thank you.

[Bin]

Hi:

In VL53L7CX datasheet, when the reflectance is 17% and under 5klx ambient, we can get min distance 500mm in inner zone and min distance 450mm in corner zone. 

In VL53L8CX datasheet, when the reflectance is 17% and under 5klx ambient, we can get min distance 1600mm in inner zone and min distance 1500mm in corner zone. 

if you follow the measurement conditions, it should can cover your requirement. 

Below is the datasheet link of L7CX and L8CX:

Datasheet - VL53L7CX - Time-of-Flight 8x8 multizone ranging sensor with 90° FoV

Datasheet - VL53L8CX - Low-power high-performance 8x8 multizone Time-of-Flight (ToF) sensor

 

Best regards,

Bin FAN

[netmirrorapp3]

With NetMirror, the key point is that the VL53L7CX does not have a fixed maximum distance specifically for black objects. Its advertised maximum is 3.5 m, but that is under favorable target and lighting conditions. For a very dark or black target, the practical range can be much shorter because less 940 nm IR light returns to the sensor. In real-world testing, black objects may become unreliable around 10–20 cm, depending on surface reflectivity, ambient light, timing budget, and the 4×4/8×8 configuration. ST community testing also reports unstable readings beyond about 200 mm with a black target. So if your requirement is reliable black-object detection at 50 cm, I would test the exact target and increase the timing budget if possible rather than assuming the 3.5 m specification will apply.

[AScha.3]

Hi,

you know, these kind of sensors working by detecting a reflected light-pulse .

So basically a perfekt not-reflecting ( 100% black) surface is by definition of working principle invisible for them.

So maximum detection distance for not-reflecting ( 100% black) is impossible to give, or zero, if you prefer.