Innovative global approach for high-performance low-cost integral field unit (IFU)

The current Integral Field Units (IFUs) are limited either by their cost/risk or by their performance. In particular, standard glass manufacturing techniques allow reaching high level of performances: accurate roughness (high throughput), sharp edges (about 1 micron), surface form (image quality), etc. in spite of their reputation to be costly and risky. Combining high performances and low costs is challenging. By coupling fast tools specifically developed at LAM to design IFU, and innovative low-cost and low-risk methods of manufacturing, we are able to reach high performances while saving costs and time by an order of magnitude. We have developed a demonstrator which validates our tools and manufacturing methods in terms of optical image quality, slice edges quality and decentring errors. We will present these results and an example of IFU designed with our tools. All these processes of optimization between manufacturing techniques and design can be applied for future ground-based instruments (MUSE, KMOS for the VTL; MOMFIS of the ELT) or into future space instruments (SNAP).