MANIFEST filter box: a conceptual optical and opto-mechanical design

The Filter Box (FB) is one of the several subsystems that compose the Many Instrument Fiber System (MANIFEST) of the Giant Magellan Telescope (GMT). With this filtering system, MANIFEST will be integrated to the GMT-Consortium Large Earth Finder (G-CLEF) to efficiently fill it with valuable data from multiple targets. As the FB follows strict requirements flow-down from MANIFEST’s facilities, it is suitable for it to be designed from the outset in a manner that avoids the use of commercial-of-the-shelf filter systems. Hence, this paper presents the optical and mechanical FB conceptual designs, having its operation modes divided into three categories (A, B and C) comprising three, 21 and 54 single light sources of different wavelength coverages. The results show that an enhanced optical throughput is achieved when such sources (optical fibers) are attached to rod-like optical elements, denoted as Rod-lenses, and coupled into U-shaped mechanical lens cells, while following accessible manufacturing tolerances.