VL53L8 smalles FoV

[daan]

Hi,

I have a project for which I need to measure a tank level of tanks with a maximum depth of 3 meters. The challenging part is that many tanks have filling tubes with an inner diameter of 50mm but a length of 1000mm worst case. I have made this drawing:

The maximum field of view is thus 2.86 degrees in the worst case scenario. I have ordered a VL53L8 development kit and tested it out thinking that the matrix could solve this issue for us. I tested this, but it is a no-go as all measurements drop as soon as I place a tube on top of the sensor. 

I found it really difficult to select a correct sensor and I probably need a sensor with a narrower lens. But I cannot find a sensor that can se as far as I need (4m in total darkness with a low emissivity fluid (diesel fuel)), with a narrow enough field of view.

Can anybody help me out?

[Anne BIGOT]

Hello,

 

From our understanding you are looking for a sensor which could range till 4m within a tube of 5cm, isn't it ?

Having a multi-zone sensors considering your application won't really help. You could use only one zone. But there will be many bounces on the tube itself (considering the FoV of the sensor) and lot of photons will be lost in the liquid then. Moreover the probability to have photons coming back to the receiver straight from the liquid is low and at the end, the accuracy of the ranging won't be that good.

Having said that, you can try to use the VL53L1 or VL53L8, which are the most suitable devices for your application
And did you think about putting the sensor at the bottom of the tube ?

Regards

Anne 

[daan]

Hi,

If I understand your reply correctly the ST ToF sensor range doesn't contain a suitable sensor. For physical reasons it is not feasible to place the sensor at the bottom of the tube. 

Would it be possible to narrow the FoV by placing a converging lens in front of the transmitter of the sensor?

Kind regards,
Daan