Second and third optical harmonic generation in type I collagen, by nanosecond laser irradiation, over a broad spectral region

Georgiou, E; Theodossiou, T; Hovhannisyan, V; Politopoulos, K; Rapti, GS; Yova, D

dc.contributor.author	Georgiou, E	en
dc.contributor.author	Theodossiou, T	en
dc.contributor.author	Hovhannisyan, V	en
dc.contributor.author	Politopoulos, K	en
dc.contributor.author	Rapti, GS	en
dc.contributor.author	Yova, D	en
dc.date.accessioned	2014-03-01T01:15:52Z
dc.date.available	2014-03-01T01:15:52Z
dc.date.issued	2000	en
dc.identifier.issn	0030-4018	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13788
dc.subject	Harmonic Generation	en
dc.subject	Second Harmonic Generation	en
dc.subject	Spectrum	en
dc.subject	Type I Collagen	en
dc.subject	Signal Intensity	en
dc.subject	Third Harmonic Generation	en
dc.subject.classification	Optics	en
dc.subject.other	TISSUES	en
dc.title	Second and third optical harmonic generation in type I collagen, by nanosecond laser irradiation, over a broad spectral region	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0030-4018(00)00504-6	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0030-4018(00)00504-6	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	We report optical up-conversion of pulsed (ns) laser radiation in type I pure collagen, tuneable over a broad excitation spectrum covering the 760-1070 nm wavelength range. We investigated second harmonic generation (SHG) in collagen using lambda(p) = 1064, 901, 892, 828, 785 and 766 nm nanosecond pulsed laser excitation and recorded monochromatic signals at lambda(p)/2, i.e. 532, 451, 446, 414, 393 and 383 nm, respectively, corresponding to the SHG optical process. The SHG signal intensity exhibited a quadratic dependence on the excitation radiation (log[I-532] = 1.92log[I-1064]). Furthermore, a weaker third harmonic generation (THG) signal from collagen was also observed at lambda(p)/3 (355 nm) using 1064 nm nanosecond pulsed laser excitation. The THG signal was found to have near-cubic dependence upon the irradiation laser intensity (log[I-356] = 2.53log[I-1064]). The significance of collagen ability to exhibit broadly tuneable second harmonic generation is discussed. (C) 2000 Published by Elsevier Science B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	OPTICS COMMUNICATIONS	en
dc.identifier.doi	10.1016/S0030-4018(00)00504-6	en
dc.identifier.isi	ISI:000085887600035	en
dc.identifier.volume	176	en
dc.identifier.issue	1-3	en
dc.identifier.spage	253	en
dc.identifier.epage	260	en