Ideas

Optical Properties of Skin

Human skin exhibit different optical properties depnding on the wavelength of the electromagnetic wave under study. The properties can even change because they are highly dependent on the hydration and thickness of the skin sample.

Optical properties of skin, subcuateous..

Optical propertis of human skin

Optical properties of human skin in the near infrared wavelength range of 1000 to 2200nm

Zone Plates

A zone plate can focus light using Fresnel diffraction instead of refraction. It is made on a small piece of transparent material such as glass or plastic and has concentric opaque circles printed onto the plate. These plates are placed so that the inference of the light creates zones of constuctive inteference. Ways of making your own plate.

Some math behind Fresnel zone plates

Hyperspectral Imaging

Hyperspectral Imaging collects the spectrum of an object or an area in many bands which can result in high resolution images. These high resolution images would be useful for agriculture, mining, and contractors when large areas of land need to be surveyed for composition.

There are four basic ways of hyperspectral imaging or HSI: spatial scanning, spectral scanning, non-scanning, and spatio-spectral scanning.

With spatial scanning, the total section of one line of area is found before moving onto the next while spectral scanning finds one spectra of the total area at a time. Non-scanning or snapshot just takes the spectra of the outside of the area instead of the layers underneath. Spatio-Spectral scanning measures the spectra but decreases the area of which specific spectra correspond to.

DIY hyperspectral camera

Medical hyperspectrak imaging: a review

Biological imaging with coherent Raman scattering microscopy: a tutorial

     Raman Spectroscopy

Spectroscopy

Spectroscopy studies the intereaction between matter and radiated energy as a function of wavelength. Spectroscopy is useful when finding the composition of an object because different elements have different spectra. Spectroscopy using a sample of rubdium and a diode laser has been done several times in the LTC, for example Bob Azmoun and Susan Metz did an intensive study of it.

White Light Interferometry

    Speckle patterns

        Princeton's explanation

         A beginner's guide to speckle

         The Statistics of Speckle Patterns

         Signal-to-Noise Ratio (SNR)

Raman Scattering

Raman Spectroscopy Experiment for the Senior Laboratory. Written by B.R. Fugitt and A.S. Rupaal

Biological Imaging with coherent Raman scattering microscopy: a tutorial. Alfonso-Garcia;Mittal;Seong Lee;Potma

Ronchi Test

A new Ronchi tester Nunez-Alfonso, Cordero-Davila, Vergara-Limon, Cuautle-Cortes

Error Analysis in a Device to Test Optical Systems by Using Ronchi Test and Phase Shifting. Cabera-Perez, Castro-Ramos, Gordiano-Alvarado, Vazquez y Montiel