radiationtosignal

Radiation-to-signal is a term used in detector technology to describe the process by which energy from incident radiation is converted into a measurable electrical or optical signal. This concept lies at the heart of instruments that quantify radiation fields, energies, fluxes, or doses. A radiation-to-signal system typically couples a radiation interaction medium with a transducer that produces a detectable output, aiming for a signal that is proportional to the radiation of interest over a defined range.

The conversion can occur via direct or indirect mechanisms. In direct conversion, radiation interacts with a semiconductor detector, generating electron-hole pairs that are collected to form an electrical current or charge pulse. In indirect conversion, radiation first excites a scintillator material that emits photons; these photons are then detected by a photodetector such as a photomultiplier tube or a silicon photomultiplier, producing an electrical signal. Other approaches include bolometric or pyroelectric detectors that respond to deposited energy with a change in temperature or polarization.

Common detector configurations employ materials such as silicon, germanium, or compound semiconductors for direct conversion, and scintillators like sodium iodide, cesium iodide, or bismuth germanate for indirect conversion. Applications span medical imaging (for example, gamma-ray and positron emission tomography), nuclear spectroscopy, radiation dosimetry, security screening, and space-based astronomy.

Performance is characterized by factors including energy and timing resolution, detection efficiency, linearity, noise, and radiation hardness. Calibration uses known radiation sources and accounts for temperature, background, and aging effects to maintain accurate signal interpretation.