Reflection of near-infrared light confers thermal protection in birds

Thermal infrared near-field spectroscopy.

Despite the seminal contributions of Kirchhoff and Planck describing far-field thermal emission, fundamentally distinct spectral characteristics of the electromagnetic thermal near-field have been predicted. However, due to their evanescent nature their direct experimental characterization has remained elusive. Combining scattering scanning near-field optical microscopy with Fourier-transform s...

Near-infrared light photoacoustic ophthalmoscopy

We achieved photoacoustic ophthalmoscopy (PAOM) imaging of the retina with near-infrared (NIR) light illumination. A PAOM imaging system with dual-wavelength illumination at 1064 nm and 532 nm was built. We compared in vivo imaging results of both albino and pigmented rat eyes at the two wavelengths. The results show that the bulk optical absorption of the retinal pigment epithelium (RPE) is on...

Quantitative Comparison of Analytical solution and Finite Element Method for investigation of Near-Infrared Light Propagation in Brain Tissue Model

Introduction: Functional Near-Infrared Spectroscopy (fNIRS) is an imaging method in which light source and detector are installed on the head; consequently, re-emission of light from human skin contains information about cerebral hemodynamic alteration. The spatial probability distribution profile of photons penetrating tissue at a source spot, scattering into the tissue, and being released at ...

A Survey of Near Infrared Emission in Visual Reflection Nebulae

We present a survey for extended 2.2 μm emission in 20 new visual reflection nebulae, illuminated by stars with temperatures of 3,600 — 33,000 K. We detect extended 2.2 μm emission in 13 new nebulae, illuminated by stars with temperatures of 6,800 – 33,000 K. For most of these 13 nebulae we have measured J −K, H −K, and K −L, as well as obtaining surface brightness measurements at the wavelengt...

Evaluation of Reflection Optical Imaging Characteristics Using Fluorescence with Near Infrared Wavelength at Different Depths of Tissue Equivalent Phantom