Far infrared (FIR) refers to a specific range within the infrared spectrum of electromagnetic radiation. It encompasses radiation with wavelengths ranging from 15 μm (micrometers) to 1 mm, which corresponds to a frequency range of approximately 20 THz to 300 GHz. This places far infrared radiation within the CIE IR-B and IR-C bands.[1] The longer wavelengths of the FIR spectrum overlap with a range known as terahertz radiation.[2] Different sources may use different boundaries to define the far infrared range. For instance, astronomers often define it as wavelengths between 25 μm and 350 μm.[3] Infrared photons possess significantly lower energy than photons in the visible light spectrum, with tens to hundreds of times less energy. [4]
Objects within a temperature range of approximately 5 K to 340 K emit radiation in the far infrared range as a result of black-body radiation, in accordance with Wien's displacement law. This characteristic is utilized in the observation of interstellar gases, which are frequently associated with the formation of new stars.
The brightness observed in far infrared images of the center of the Milky Way galaxy arises from the high density of stars in that region, which heats the surrounding dust and induces radiation emission in the far infrared spectrum. Excluding the center of the Milky Way galaxy, the galaxy M82 is the most prominent far-infrared object in the sky, with its central region emitting amounts of far infrared light equivalent to the combined emissions of all the stars in the Milky Way. As of 29 May 2012[update], the source responsible for heating the dust at the center of M82 remains unknown.[3]
Human body detectionedit
Certain human proximity sensors utilize passive infrared sensing within the far infrared wavelength range to detect the presence of stationary[5] and/or moving human bodies.[6]
Researchers have observed that among all forms of radiant heat, only far-infrared radiation transfers energy solely in the form of heat that can be sensed by the human body.[7] They have found that this type of radiant heat can penetrate the skin up to a depth of approximately 1.5 inches (3.8 cm). In the field of biomedicine, experiments have been conducted using fabrics woven with FIR-emitting ceramics embedded in their fibers. These studies have indicated a potential delay in the onset of fatigue induced by muscle contractions in participants.[8] The researchers have suggested that the emission of far-infrared radiation by these ceramics (referred to as cFIR) could facilitate cellular repair.
Certain heating pads have been marketed to provide "far infrared" therapy, which is claimed to offer deeper penetration.[citation needed] However, the infrared radiation emitted by an object is determined by its temperature. Therefore, all heating pads emit the same type of infrared radiation if they are at the same temperature. Higher temperatures will result in greater infrared radiation, but caution must be exercised to avoid burns.
Referencesedit
^Byrnes, James (2009). Unexploded Ordnance Detection and Mitigation. Springer. pp. 21–22. ISBN978-1-4020-9252-7.
^Glagoleva-Arkadiewa, A. (1924). "Short electromagnetic waves of wave-length up to 82 Microns". Nature. 2844 (113): 640. doi:10.1038/113640a0.
^ ab"Near, mid and far-infrared". Caltech Infrared Processing and Analysis Center. California Institute of Technology. Archived from the original on 2012-05-29. Retrieved 2013-01-28.
^Gregory Hallock Smith (2006), Camera lenses: from box camera to digital, SPIE Press, p. 4, ISBN978-0-8194-6093-6
^"Pyroelectric Detectors & Sensors for Far Infrared, FIR (5.0 μm – 15 μm)". Excelitas. Retrieved 7 August 2015.
^Vatansever, Fatma; Hamblin, Michael R. (2012). "Far infrared radiation (FIR): Its biological effects and medical applications". Photonics & Lasers in Medicine. 1 (4): 255–266. doi:10.1515/plm-2012-0034. PMC3699878. PMID 23833705.
^Leung, Ting-Kai (2011). "A Pilot Study of Ceramic Powder Far-Infrared Ray Irradiation (CFIR) on Physiology: Observation of Cell Cultures and Amphibian Skeletal Muscle". The Chinese Journal of Physiology. 54 (4): 247–254. doi:10.4077/CJP.2011.AMM044. PMID 22129823.
External linksedit
Vatansever, F.; Hamblin, M.R. (1 November 2012) [16 October 2012]. "Far infrared radiation (FIR): Its biological effects and medical applications". Photonics & Lasers in Medicine. 1 (4): 255–266. doi:10.1515/plm-2012-0034. PMC3699878. PMID 23833705.
Niklaus, S.; Albertini, S.; Schnitzer, T.K.; Denk, N. (March 2020). "Challenging a myth and misconception: Red-light vision in rats". Animals. Basel, CH. 10 (3): 422. doi:10.3390/ani10030422. PMC7143485. PMID 32138167.
February 15, 2024
infrared, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, scholar, jstor, october, 2012, le. This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Far infrared news newspapers books scholar JSTOR October 2012 Learn how and when to remove this template message Far infrared FIR refers to a specific range within the infrared spectrum of electromagnetic radiation It encompasses radiation with wavelengths ranging from 15 mm micrometers to 1 mm which corresponds to a frequency range of approximately 20 THz to 300 GHz This places far infrared radiation within the CIE IR B and IR C bands 1 The longer wavelengths of the FIR spectrum overlap with a range known as terahertz radiation 2 Different sources may use different boundaries to define the far infrared range For instance astronomers often define it as wavelengths between 25 mm and 350 mm 3 Infrared photons possess significantly lower energy than photons in the visible light spectrum with tens to hundreds of times less energy 4 Diagram of part of the electromagnetic spectrum Contents 1 Applications 1 1 Astronomy 1 2 Human body detection 1 3 Therapeutic modality 2 References 3 External linksApplications editAstronomy edit Main article Far infrared astronomy Objects within a temperature range of approximately 5 K to 340 K emit radiation in the far infrared range as a result of black body radiation in accordance with Wien s displacement law This characteristic is utilized in the observation of interstellar gases which are frequently associated with the formation of new stars The brightness observed in far infrared images of the center of the Milky Way galaxy arises from the high density of stars in that region which heats the surrounding dust and induces radiation emission in the far infrared spectrum Excluding the center of the Milky Way galaxy the galaxy M82 is the most prominent far infrared object in the sky with its central region emitting amounts of far infrared light equivalent to the combined emissions of all the stars in the Milky Way As of 29 May 2012 update the source responsible for heating the dust at the center of M82 remains unknown 3 Human body detection edit Certain human proximity sensors utilize passive infrared sensing within the far infrared wavelength range to detect the presence of stationary 5 and or moving human bodies 6 Therapeutic modality edit This section contains content that is written like an advertisement Please help improve it by removing promotional content and inappropriate external links and by adding encyclopedic content written from a neutral point of view July 2019 Learn how and when to remove this template message Researchers have observed that among all forms of radiant heat only far infrared radiation transfers energy solely in the form of heat that can be sensed by the human body 7 They have found that this type of radiant heat can penetrate the skin up to a depth of approximately 1 5 inches 3 8 cm In the field of biomedicine experiments have been conducted using fabrics woven with FIR emitting ceramics embedded in their fibers These studies have indicated a potential delay in the onset of fatigue induced by muscle contractions in participants 8 The researchers have suggested that the emission of far infrared radiation by these ceramics referred to as cFIR could facilitate cellular repair Certain heating pads have been marketed to provide far infrared therapy which is claimed to offer deeper penetration citation needed However the infrared radiation emitted by an object is determined by its temperature Therefore all heating pads emit the same type of infrared radiation if they are at the same temperature Higher temperatures will result in greater infrared radiation but caution must be exercised to avoid burns References edit Byrnes James 2009 Unexploded Ordnance Detection and Mitigation Springer pp 21 22 ISBN 978 1 4020 9252 7 Glagoleva Arkadiewa A 1924 Short electromagnetic waves of wave length up to 82 Microns Nature 2844 113 640 doi 10 1038 113640a0 a b Near mid and far infrared Caltech Infrared Processing and Analysis Center California Institute of Technology Archived from the original on 2012 05 29 Retrieved 2013 01 28 Gregory Hallock Smith 2006 Camera lenses from box camera to digital SPIE Press p 4 ISBN 978 0 8194 6093 6 Mems Thermal Sensors Omron Electronic Components Web Omron Retrieved 7 August 2015 Pyroelectric Detectors amp Sensors for Far Infrared FIR 5 0 mm 15 mm Excelitas Retrieved 7 August 2015 Vatansever Fatma Hamblin Michael R 2012 Far infrared radiation FIR Its biological effects and medical applications Photonics amp Lasers in Medicine 1 4 255 266 doi 10 1515 plm 2012 0034 PMC 3699878 PMID 23833705 Leung Ting Kai 2011 A Pilot Study of Ceramic Powder Far Infrared Ray Irradiation CFIR on Physiology Observation of Cell Cultures and Amphibian Skeletal Muscle The Chinese Journal of Physiology 54 4 247 254 doi 10 4077 CJP 2011 AMM044 PMID 22129823 External links editVatansever F Hamblin M R 1 November 2012 16 October 2012 Far infrared radiation FIR Its biological effects and medical applications Photonics amp Lasers in Medicine 1 4 255 266 doi 10 1515 plm 2012 0034 PMC 3699878 PMID 23833705 Niklaus S Albertini S Schnitzer T K Denk N March 2020 Challenging a myth and misconception Red light vision in rats Animals Basel CH 10 3 422 doi 10 3390 ani10030422 PMC 7143485 PMID 32138167 Retrieved from https en wikipedia org w index php title Far infrared amp oldid 1195049827, wikipedia, wiki, book, books, library,
