How to use photocell

How to use a photoresistor (or photocell)?

How to Use a Photoresistor (or Photocell) - Arduino Tutorial: A photoresistor or photocell is a light-controlled variable resistor. The resistance of a photoresistor decreases with increasing incident light intensity. A photoresistor can be applied in light-sensitive detector circuits, and light- and dark-acti…

What are photocells & how do they work?

Photocells are sensors that allow you to detect light. They are small, inexpensive, low-power, easy to use and don't wear out. For that reason they often appear in toys, gadgets and appliances. They are are often referred to a CdS cells (they are made of Cadmium-Sulfide), light-dependent resistors (LDR), and photoresistors.

How do you use a photocell?

Photocells are pretty hardy, you can easily solder to them, clip the leads, plug them into breadboards, use alligator clips, etc. The only care you should take is to avoid bending the leads right at the epoxied sensor, as they could break off if flexed too often. Noisemaker that changes frequency based on light level.

Are photocells a good choice?

For most light-sensitive applications like "is it light or dark out", "is there something in front of the sensor (that would block light)", "is there something interrupting a laser beam" (break-beam sensors), or "which of multiple sensors has the most light hitting it", photocells can be a good choice!

What is a photocell sensor?

A Photocell is basically a resistor that changes its resistive value (in ohms) depending on how much light is shining onto the squiggly face. They are very low cost, easy to get in many sizes and specifications, but are very inaccurate. Each photocell sensor will act a little differently than the other, even if they are from the same batch.

How do you connect a photocell to an Arduino?

Breadboard and Jumper Wires -- The photocell's legs, like any through-hole resistor, can be bent and shaped to fit. We'll stick them and the resistor into a breadboard, then use the jumper wires to connect from breadboard to Arduino. Resistors are a good thing, in fact, they're actually crucial in a lot of circuit designs.