A new photolithography based technique to mass produce microlens+fibre based integralfield units (IFUs) for 2D spectroscopy

TL;DR

This paper introduces a novel photolithography-based method for efficiently mass producing microlens-fibre integral field units, enhancing 2D spectroscopy capabilities for telescopic instruments.

Contribution

The paper presents a new photolithography technique for fabricating microlens-fibre IFUs with high precision, suitable for mass production and cost-effective deployment.

Findings

Achieved +/- 5 micron accuracy in microlens-fibre pairing.

Developed a copper mask photolithography process for IFU fabrication.

Demonstrated the potential for scalable, efficient production of IFUs.

Abstract

We present a novel photolithography based technique to efficiently fabricate microlens-fibre based Integral Field Units (IFUs). These IFUs are being developed for Devasthal Optical Telescope Integral Field Spectrograph (DOTIFS) which offer sixteen deployable IFUs. In each IFU, a 12 x 12 microlens array is matched with a similar array of fibres to better than +/- 5 micron accuracy for each microlens-fibre pair in the array. A mask created on copper foils using photolithography, transfer the pupil spot pattern of each microlens array to a fibre array holder. The approach can be used for mass production of IFUs in an extremely efficient and cost-effective manner.