Abstract Details
| Name: Nitish Singh Affiliation: Indian Institute of Astrophysics Bengaluru Conference ID: ASI2025_125 Title : Design, Fabrication, and Performance Analysis of a Wide-Field Camera for the VBT Prime Focus Authors and Co-Authors : Nitish Singh, S Sriram, Bharat Kumar Yerra Abstract Type : Poster Abstract Category : Facilities, Technologies and Data science Abstract : Over the past few decades, newer and more efficient telescopes have been built worldwide at sites with good seeing conditions. When discussing older-generation telescopes, it becomes imperative to focus on enhancing their efficiency and integrating new technologies to keep them competitive and relevant in modern astronomy. The Vainu Bappu Observatory is home to 0.5 to 2-m class telescopes, including the Vainu Bappu Telescope (VBT). The VBT is a 2.34m reflecting telescope that comprises parabolic primary and hyperbolic secondary mirror systems. To enable wide-field imaging and multi-object spectroscopy, telescopes require a large FoV and a substantial light-collecting area that ensures high image quality across the entire field. To achieve this, a system of optical elements known as the Wide-Field Camera (WFC) is essential. The Indian Institute of Astrophysics (IIA) has designed, developed, and fabricated a compact, lightweight, three-element WFC using spherical lenses for the 2.34-meter VBT prime focus in its laboratory. This WFC enables a wider FoV of 0.5 degrees, with an optional Atmospheric Dispersion Corrector (ADC) that reduces aberrations across the wide field without requiring additional optical elements. The WFC has already been fabricated, and its mount has been constructed in the IIA laboratory. We conducted laboratory tests of the WFC, including wavefront error measurements using a ZYGO interferometer and spot size analysis with a combination of lenses and a CMOS detector, which demonstrate that the WFC delivers sharp images over a 0.5-degree FoV. We are now preparing to install the WFC at the VBT’s prime focus and will present preliminary photometric results following its installation. In this conference, I will present the design, fabrication, and testing results of the WFC. |