A photocell is also known as an electronic eye and it is quite similar to a small solar cell. When there is light thrown on the semiconductor material in a photocell, it generates small current and voltage. A photocell sensor can effectively be used for detecting ambient lighting. An example of this would be the way night lights turn off during the day. Photocell sensors can even be paired with lighting intended to glow on them in alarm systems. Here, these sensors can be used for detecting when the light gets interrupted. To be very specific, it can be said that photocell sensors help individuals in detecting light.
The Use of Photocell Sensors
A photocell sensor is an inexpensive, minuscule, easy to use and low power device that does not wear out. It is only because of this reason that these sensors are generally found in gadgets, appliances and toys. These sensors are also called CdS cells as they are made using Cadmium-Sulfide. The other names for these sensors include photoresistors and LDR or light-dependent resistors. These sensors work in the form of resistors that change their resistive value depending on the amount of light that shine onto a face.
You can get them in different specifications and sizes but most of them tend to be inaccurate. The different specifications of these sensors available in the market work in a bit different way than the other despite the fact that they might be from the same batch. There can be large variations and therefore they must never be used for determining precise lighting levels. They are best used for detecting basic lighting changes. Photocell sensors can serve as the perfect choice for the most light-sensitive uses.
What are PIR Sensors?
A PIR sensor tends to be more complicated in comparison to the other sensors available in the market. This is mainly due to the fact that there are several variables affecting the input and the output of these sensors. PIR sensors carry out the task of detecting human movement around within a range of 10m from the sensor. Here, it is important to note that the best sensors in this category come with a detection range that is between 5m and 12m. PIRs are basically made using pyro electronic sensors that have the ability of detective several levels of infrared radiation.
Article Resource from – https://medium.com/@pixelweb17/using-a-photocell-sensor-for-light-sensitive-applications-b605b8e02556
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