The original ROTSE-I had 4 telephoto lenses of 11 cm aperture, covering a 16x16 degree field of view. This detected the first afterglow of a GRB while the burst was still ongoing, but this was the only burst detected by ROTSE or the very similar Livermore Optical Transient Imaging System. Therefore, ROTSE-II was designed, also featuring a large field of view, but it was never built, since new satellites such as HETE-2 and SWIFT could provide smaller error boxes, making a huge field of view unnecessary. This led to the design of ROTSE-III, a more or less conventional telescope designed for fast slewing and operation at multiple locations around the world.[3]
^Akerlof, C.W. and Ashley, MCB and Casperson, DE and Epps, HW and Kehoe, RL and Marshall, SL and McGowan, KE and McKay, TA and Phillips, MA and Rykoff, E.S.; et al. (2002). "The ROTSE-III robotic telescope system". Publications of the Astronomical Society of the Pacific. 115 (803): 132–140. arXiv:astro-ph/0210238. Bibcode:2003PASP..115..132A. doi:10.1086/345490. S2CID10152025.{{cite journal}}: CS1 maint: multiple names: authors list (link)