Simple optical proximity sensor

[Catcatcat]

I would like to share a project to create a simple optical proximity sensor that can be used as an optical limit switch or used as, for example, a proximity light switch. A special feature in this project is the principle of protection against parasitic infrared study and simple logic of work. It can be used as a basis for development. In the ready-made firmware for the project, there are options, an optical limit switch, an optical light switch, and an optical switch with auto-off time.

More details here

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Additional materials for the project for its repetition:

Simple optical proximity sensor (diagram)

Simple optical proximity sensor (draft) Password to download the project as usual

Simple optical proximity sensor (firmware)

Simple optical proximity sensor (firmware, switch mode 2)

Simple optical proximity sensor (firmware, switch mode)

Simple optical proximity sensor (firmware, shutdown delay mode 2 sec.)

Simple optical proximity sensor, 3D model

PCB prototype, complete, optical limit switch

[Unhappy]

sorry , unable to down load the project  with usual password all small letters

[Catcatcat]

sorry , unable to down load the project  with usual password all small letters

Write to me at [email protected] I will send you the project by mail

[Jatayu]

Catcatcat, thank you for project!

What is the maximum sensor response distance?
For miniature devices, you can also use ITR8307 proximity sensor. But it has a short actuation distance.

https://www.everlight.com/file/ProductFile/ITR8307.pdf

https://www.youtube.com/watch?v=W0sWB0piA-0
https://www.youtube.com/watch?v=VjfJTH6r6xY

https://aliexpress.ru/item/10PCS-ITR8307-S17-TR8-B-8307/32715815106.html

[Catcatcat]

It all depends on the photodetector and the LED itself. In the project, for the optical limit switch, I tried to reduce the sensitivity, so that it would not be more than 20 cm (by reducing the pulse duration in PWM), but in reality, when tested by 1 meter, it worked fine.

[vern]

I have a project where I use a VCNL4200 proximity sensor, very small and simple with I2C connection. It includes the LED, the detector and a driver for shorter distances ~30cm . For longer distances you need to add a small Mosfet
Distance up to 1.5 meter depending on configuration.

[an007_rld]

Guys,

As a nice and cost effective alternative, you can take a look to VL53 series from ST. Works up to 8m (VCSEL + detection SPAD area + required circuitry) and they provide an easy to use API to build your application:
https://www.st.com/en/imaging-and-photonics-solutions/proximity-sensors.html#products

Hope that helps,
Best Regards,
-an