Search results
Results from the WOW.Com Content Network
A nondispersive infrared sensor (or NDIR sensor) is a simple spectroscopic sensor often used as a gas detector.It is non-dispersive in the fact that no dispersive element (e.g a prism or diffraction grating as is often present in other spectrometers) is used to separate out (like a monochromator) the broadband light into a narrow spectrum suitable for gas sensing.
An infrared detector is a detector that reacts to infrared (IR) radiation. The two main types of detectors are thermal and photonic (photodetectors). The thermal effects of the incident IR radiation can be followed through many temperature dependent phenomena. [2] Bolometers and microbolometers are based on changes in resistance.
Dual source and dual receivers are used for self compensation of changes in alignment, light source intensity and component efficiency. The transmitted beams from two infrared sources are superimposed onto an internal beam splitter. 50% of the overlapping sample and reference signal is passed through the gas measuring path and reflected back onto the measuring detector.
NDIR sensors are most often used for measuring carbon dioxide. [2] The best of these have sensitivities of 20–50 PPM. [2] Typical NDIR sensors cost in the (US) $100 to $1000 range. NDIR CO 2 sensors are also used for dissolved CO 2 for applications such as beverage carbonation, pharmaceutical fermentation and CO 2 sequestration applications.
A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors . PIR sensors are commonly used in security alarms and automatic lighting applications.
The design from 1975 (pictured above) is a Nondispersive infrared sensor. It is the first improved analyzer that is able to detect more than one component of a sample gas at one time. Earlier analyzers were held back by the fact that a particular gas also has lower absorption bands in the infrared.
Consumer IR, consumer infrared, or CIR is a class of devices employing the infrared portion of the electromagnetic spectrum for wireless communications. [ citation needed ] CIR ports are commonly found in consumer electronics devices such as television remote controls , PDAs , laptops , computers , and video game controllers.
Infrared cut-off filters, sometimes called IR filters or heat-absorbing filters, are designed to reflect or block near-infrared wavelengths while passing visible light. They are often used in devices with bright incandescent light bulbs (such as slide and overhead projectors ) to prevent unwanted heating.