dbomse's lamellar [3 articles]

Abstract

A high-resolution, far ir lamellar grating interferometer that operates in either a single-beam or a double-beam differencing mode of operation is described. The instrument covers a frequency range of 10 cm-1 to 125 cm-1 (1000 µ to 80 µ). To illustrate the general performance of the instrument the pure rotational spectrum of water vapor between 15 cm-1 and 115 cm-1 is presented. It is estimated that the absorption line centers of strong isolated lines are measured to within ±0.008 cm-1. To ...

Abstract

We present a lamellar grating interferometer realized with microelectromechanical system technology. It is used as a time-scanning Fourier-transform spectrometer. The motion is carried out by an electrostatic comb drive actuator fabricated by silicon micromachining, particularly by silicon-on-insulator technology. For the first time to our knowledge, we measure the spectrum of an extended white-light source with a resolution of 1.6 nm at a wavelength of 400 nm and of 5.5 nm at 800 nm. The wavelength accuracy is better than 0.5 nm, ...

Abstract

A lamellar grating Fourier transform infra-red (FTIR) micro-spectrometer is presented in which the device is electromagnetically actuated in resonant mode so as to achieve larger displacements with a lower driving voltage. By actuating at resonance,we can also have a design with a higher spring stiffness design such that the micro-spectrometer will have little influence from external perturbation. A data acquisition electronic system is designed such that the interferogram of the IR source can still be acquired at a fixed optical path ...