3D-printed miniature spectrometer for the visible range with a 100 × 100 μm² footprint

Abstract

The miniaturisation of spectroscopic measurement devices opens novel information channels for size critical applications such as endoscopy or consumer electronics. Computational spectrometers in the micrometre size range have been demonstrated, however, these are calibration sensitive and based on complex reconstruction algorithms. Herein we present an angle-insensitive 3D-printed miniature spectrometer with a direct separated spatial-spectral response. The spectrometer was fabricated via two-photon direct laser writing combined with a super-fine inkjet process. It has a volume of less than 100 × 100 × 300 μm 3 . Its tailored and chirped high-frequency grating enables strongly dispersive behaviour. The miniature spectrometer features a wavelength range of 200 nm in the visible range from 490 nm to 690 nm. It has a spectral resolution of 9.2 ± 1.1 nm at 532 nm and 17.8 ± 1.7 nm at a wavelength of 633 nm. Printing this spectrometer directly onto camera sensors is feasible and can be replicated for use as a macro-pixel of a snapshot hyperspectral camera.

Electrical Breakdown Spectroscopy of Nano-/Micro-Thermites

“…This could be envisaged as yet another application of meta-materials for optical primers [15]. It is shown here that micro-thermites with and without loading with explosive chemicals can be safely operated with total load below 1 g. Further miniaturisation in energetic material characterisation can be envisaged due to the availability of microspectrometers [34]. Space-time imaging techniques based on computational holography using pinhole arrays are expected to be especially applicable to bright and dynamic events such as micro-explosions and sparks [16].…”