Ultraviolet detectors utilize detection principles that sense radiation. Which two detection principles are used in ultraviolet detectors?

Ultraviolet detectors utilize detection principles that sense radiation. Which two detection principles are used in ultraviolet detectors?

• A. Photomultiplier tube only
• B. Thermal sensing
• C. Ionization chamber
• D. Solid-state device and gas-filled tube

Answer: (D)

Ultraviolet detectors rely on two different ways to convert UV photons into an electrical signal: solid-state semiconductor devices and gas-filled tubes. Solid-state UV detectors use semiconductor materials that absorb UV light and create electron-hole pairs, generating a measurable current or signal. They’re fast, compact, and robust, making them a common choice for UV sensing. Gas-filled detectors, on the other hand, operate by UV photons ionizing gas inside a tube, producing free charges that are collected to form a current or pulse. This is a distinct detection principle from solids and has different response characteristics. The other options don’t capture this dual-principle idea: a photomultiplier tube is a vacuum-tube device rather than a fundamental detection principle, thermal sensing isn’t appropriate for UV detection, and an ionization chamber is one specific gas-filled detector rather than the broad gas-filled principle paired with solid-state devices.

Ultraviolet detectors rely on two different ways to convert UV photons into an electrical signal: solid-state semiconductor devices and gas-filled tubes.

Solid-state UV detectors use semiconductor materials that absorb UV light and create electron-hole pairs, generating a measurable current or signal. They’re fast, compact, and robust, making them a common choice for UV sensing.

Gas-filled detectors, on the other hand, operate by UV photons ionizing gas inside a tube, producing free charges that are collected to form a current or pulse. This is a distinct detection principle from solids and has different response characteristics.

The other options don’t capture this dual-principle idea: a photomultiplier tube is a vacuum-tube device rather than a fundamental detection principle, thermal sensing isn’t appropriate for UV detection, and an ionization chamber is one specific gas-filled detector rather than the broad gas-filled principle paired with solid-state devices.