As the name suggests, these detectors work on a phenomenon based on the laser lighting. The device is designed in a way that triggers a bell every time whenever it is unable to see' the laser light. This means, if there is a fire of smoke near the detector, it will distract the path of light coming towards the sensor. And the very next moment, you hear the alarm indicating smoke or fire.
You can see the similar detectors in the threshold of the entry of any shopping mall or store. The laser light is fitted on one end and the photo-detector on the other. Whenever you pass through the threshold, the light gets blocked for a moment and the detector triggers a bell.
Ionization Detectors
Ionization detector is the most advanced type of smoke detection device that is based on the phenomenon of ionizing radiation. The best part with this detector lies in the fact that it is cheaper in cost and is capable of detecting even a smaller amount of smoke or heat. The device is clubbed with an ionizing chamber with two plates (designed to attract positively charges oxygen & nitrogen and negatively charged electrons).
Whenever there is smoke or fire, the smoke particles attach to the ions, due to which the current between both the plates gets dropped. This simple phenomenon triggers the alarm.
Though both types of smoke detectors are effective and popular among people but the ionizing detectors are designed to respond more quickly in comparison to the photoelectric detectors. You may choose any of them for your home or office premises but you must be aware of the technique and functioning of both the types. It will help you understand the technical fault in case of any failure, and also in switching the alarm off whenever you are cooking food in the kitchen.