A Retrofitted Metallurgical Microscope Using Light Emitting Diodes for Multi-Spectral Imaging

Versatile multispectral microscope based on light emitting diodes.

We describe the development of a novel multispectral microscope, based on light-emitting diodes, capable of acquiring megapixel images in thirteen spectral bands from the ultraviolet to the near infrared. The system captures images and spectra in transmittance, reflectance, and scattering modes. We present as examples of applications ground truth measurements for remote sensing and parasitology...

Multi-spectral imaging with infrared sensitive organic light emitting diode

Commercially available near-infrared (IR) imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits (ROIC) by indium bump bonding which significantly increases the fabrication costs of these image sensors. Furthermore, these typical III-V compound semiconductors are not sensitive to the visible region and thus ...

Logarithmic current electrometer using light emitting diodes

The limit of low current measurement using logarithmic current to voltage converter is improved by 6–7 orders of magnitude with the use of diodes of large band gap as compared with silicon diodes. Low cost commercially available light emitting diodes (LEDs) have been used for this purpose. A theoretical study and experimental measurement of device constant and reverse saturation currents of the...

Light-emitting silicon pn diodes

We report on the electrical and optical characteristics of silicon light-emitting pn diodes. The diodes are prepared by ion implantation of boron at high doses and subsequent hightemperature annealing. Under forward bias, the diodes emit infrared electroluminescence closely below the band gap of bulk Si. We present a rate-equation model for bound excitons, free excitons and free carriers which ...

ZnO - Based Light - Emitting Diodes