Understanding the GU light sensor

Support
1

What ho fellow piratical types!

I’m tinkering with my galactic unicorn, reading the light values from the onboard sensor. It’s all very exciting. I’m using the following code:

import time
from galactic import GalacticUnicorn
from picographics import PicoGraphics, DISPLAY_GALACTIC_UNICORN

gu = GalacticUnicorn()
graphics = PicoGraphics(display=DISPLAY_GALACTIC_UNICORN)

WIDTH = GalacticUnicorn.WIDTH
HEIGHT = GalacticUnicorn.HEIGHT

gu.set_brightness(0.3)
gu.clear()

while True:
    light = gu.light()
    print(light)
    time.sleep(10)

Looking at the readme.md the value returned is between 0 and 4095. Or if preferred, 256 steps of 16.

Looking at the schematic the component is:
gu-light-sensor

I have a ltr-559, the bh1745 and the as7262. This component is clearly not one of these devices. But I’d like a deeper understanding of what I looking at here, please.

Is this value representing a standardised SI unit. Lux, Lumen etc. Or is it an arbitrary value on the fixed scale of 0 - 4095? What does this component identify as, and does it have any other functions available?

Thanks in advance for any insight you maybe able to share.

Happy tinkering!

2

This may help. It’s a very simple light sensor.
Phototransistors: What Are They & How Do They Work? | Electrical4U

3

It is very simple and basic with no calibration. It just gives a simple dynamic input value to play with.

4

As suspected. Thank you to both 🫡