key words: 1064 nm dispersive Raman spectroscopy, pigment analysis, traditional red artists’ colorants Raman spectra of red colorants were obtained in-situ using a dispersive Raman microscope equipped with a 1064 nm laser source and InGaAs array detector. By employing nearIR excitation, the fluorescence of organic colorants is significantly reduced compared to visible wavelengths. Spectra prese...

While the use of liquid crystals (LCs) over the visible region is ubiquitous in flat-screen displays, there has been little by the way of applications at other wavelengths. Specifically, notwithstanding the continuing permittivity anisotropy to be found at longer wavelengths, there has been virtually no development in the microwave domain. This is largely due to the fact that scaling up the mic...

Developing multicolor upconversion nanoparticles (UCNPs) with the capability of regulating their emission wavelengths in the UV to visible range in response to external stimuli can offer more dynamic platforms for applications in high-resolution bioimaging, multicolor barcoding, and driving multiple important photochemical reactions, such as photoswitching. Here, we have rationally designed sin...

We conducted the first measurements of the direct effect of laboratory controlled BCcontamination on snow albedo in a laboratory environment. Optical measurements of natural snow intentionally doped with industrial grade BC were conducted at visible and near-infrared wavelengths. Snow albedo was measured in a (portable) integrating sphere system. The absolute spectral albedos are less than expe...

A series of miniature photometers has been developed for use as on-stream detectors in systems for liquid chromatography. All of the detectors feature dual-beam, dual-wavelength operation without mechanical or electrical switching of either wavelength or signal. The two types of detectors originally developed-ultraviolet (254 and 280 nm) and colorimetric (any two choices of visible wavelengths)...

One of the top design priorities for semiconductor chemical sensors is developing simple, low-cost, sensitive and reliable sensors to be built in handheld devices. However, the need to implement heating elements in sensor devices, and the resulting high power consumption, remains a major obstacle for the realization of miniaturized and integrated chemoresistive thin film sensors based on metal ...

We present an improved technique for imaging through turbulence at visible wavelengths using a rotation shearing pupil-plane interferometer, intended for astronomical and terrestrial imaging applications. While previous astronomical rotation shearing interferometers have made only visibility modulus measurements, this interferometer makes four simultaneous measurements on each interferometric b...

Infrared avalanche photodiode (APD) arrays represent a panacea for many branches of astronomy by enabling extremely low-noise, high-speed, and even photon-counting measurements at near-infrared wavelengths. We recently demonstrated the use of an early engineering-grade infrared APD array that achieves a correlated double sampling read noise of 0.73 e in the lab, and a total noise of 2.52 e on s...

Light as a form of electromagnetic energy has a dual wave particle nature. When describing the effects of light absorbed by a photoreceptor, the behavior of light particles is more important. The portion of the electromagnetic spectrum that interacts with the eye is wider than the portion that is used for phototransduction. It includes wavelengths of ultraviolet light (100-400nm), visible light...