Hybrid Digital Optical Module (hDOM), is a newly designed detection unit for the proposed deep-sea neutrino telescope in the South China Sea, TRopIcal DEep-sea Neutrino Telescope (TRIDENT).
An hDOM is equipped with multi-PMTs for uniform angular acceptance and additional silicon photomultipliers (SiPMs) with O(100) ps timing response.
The combination of these two kinds of optical sensors can significantly improve the detector's angular resolution and capacity for neutrino source searching.
Many challenges also arise due to the limited space in the glass vessel, power consumption and data transmission bandwidth.
This contribution will present the current process of the preliminary design of hDOM, including its mechanical structure and electronics.