Optimization of telescope focal ratios for MLA-fiber coupled Integral Field Units

TL;DR

This paper presents an analytic model to optimize telescope focal ratios for lenslet-coupled fiber systems in integral field units, enhancing efficiency in survey telescope designs.

Contribution

It introduces a new analytic model for image transfer that determines optimal telescope input beam speed for lenslet-fiber coupling.

Findings

Optimal telescope beam speed is f/11 for fibers fed at f/3.5 with 100um core.

Model helps minimize fiber focal-ratio degradation.

Design guidelines for high-efficiency survey telescopes.

Abstract

We have developed an analytic model for generic image transfer using microlens-coupled fibers to determine the telescope input beam speed that optimizes the lenslet clear aperture and minimizes fiber focal-ratio degradation. Assuming fibers are fed at f/3.5 by the lenslets, our study shows that f/11 is the optimum telescope beam speed to feed a lenslet coupled to a fiber with a 100um diameter core. These considerations are relevant for design of high-efficiency, dedicated survey telescopes that employ lenslet-coupled fiber systems.