Spectral filtering in pulsed photothermal temperature profiling of collagen tissue phantoms.
We present an experimental comparison of pulsed photothermal (PPT) profiling in collagen-based tissue phantoms utilizing different midinfrared spectral bands. Laser-induced temperature profiles are reconstructed using a custom optimization code within the customary monochromatic approximation. Both experimental results and a detailed numerical simulation of the procedure demonstrate that, despite the associated reduction of signal-to-noise ratio, appropriate spectral filtering reduces the broadening of temperature peaks and thus improves the accuracy of temperature profiling. For our experimental system, best performance is obtained when applying a long-pass filter with cut-on wavelength at 3.4-3.8 microm. Because our collagen gel mimics infrared and thermal properties of human skin, we believe that this conclusion is transferrable to PPT radiometric profiling of human skin in vivo.
Milanic
Matija
M
Jozef Stefan Institute, Complex Matter Department, Jamova 39, Ljubljana, Slovenia. matija.milanic@ijs.si
Majaron
Boris
B
D000465:Algorithms; D000818:Animals; D002417:Cattle; D003094:Collagen / Q000032:analysis / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007834:Lasers; D008954:Models, Biological; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D019339:Port-Wine Stain; D011874:Radiometry / Q000379:methods; D012867:Skin / Q000737:chemistry; D013696:Temperature; D013817:Thermography / Q000295:instrumentation / Q000379:methods*
D003094:Collagen