Touchless HID USB keypad using light sensors

Hi,
I would be very glad to get some help for my project :slight_smile:

I want to use the Arduino as an touchless USB Keyboard. I am going to use this tutorial: Arduino UNO as a USB keyboard (HID device) [Anything Arduino] (ep 6) - YouTube

However the "keys/buttons" should be analog or digital sensors. In this case I would like to use 4 photosensitive sensors as my keys. (like this one for example: www.ebay.com/itm/221483678359)

The idea is to build a touchless keypad with light sensors. Around every light sensor radiate bright SMDs/LEDs light upwards. When a hand is over these SMDs the light sensor will notice this through the upscaling in lux. This should than trigger the keystroke "Space" or "key arrow left" for example.

I do know how to use the Arduino as an USB Keyboard and I also know how to read the lux level from a light sensor (following this tutorial: Light Sensor for Arduino- BH1750 Tutorial - YouTube).

However I do not know how to tell the Arduino that if the light sensor 1/2/3/4 reads a lux above 1000 to power up button pin 1/2/3/4.

I am glad for any help! Maybe someone knows a similar project from where I can learn from or he/she wants to realize this project too :slight_smile:

Alex

What is the button pin 1/2/3/4? Is it connected with arduino also?