Quasi-Optical THz Detectors

Home   |   Product Categories   |   Quasi-Optical THz Detectors

High sensitivity in ultra-wide frequency band and room-temperature operation make ACST Schottky-barrier diode (SBD) based Quasi-Optical detectors the best alternative to available free-space detectors for the low-THz frequency-region.

Bias-free operation allows for system simplicity and ultra-low noise. In contrast to typical THz detectors, the ACST SBD solution is simpler, geometrically smaller, and much faster. Using the Detectors is simple, lowering training efforts significantly. Different options allow adaptation to specific tasks like high sensitivity for CW or ultra-high bandwidth applications.

ACST optionally offers also a dedicated power supply unit, which considerably simplify the detector installation and exploitation in customer setups. Detector output is connected to a SMA connector, female.

Currently there are three versions of Quasi-Optical THz Detectors (QOD) available at ACST.

The …A1 and …A2 versions have an integrated video-amplifier and stabilization stages for the power supply. This crucially simplifies handling procedures concerning ESD-hazard and reduces requirements for powering the amplifier.

All these detectors use essentially similar diodes, similar antennas, similar lens, and differ only by the integrated amplifier and the metallic housing. Therefore, the THz frequency response is expected similar for all these detectors. The difference is only absolute responsivity and NEP values, which depend on the used amplifier and its mismatch with the diode. Each version is shortly described in the following sections.

ACST offers a 12 month warranty for all types of Quasi-Optical Detectors. This warranty covers any defect of the detector, but only in the case of proper handling and exploitation by the customer.

Furthermore, ACST offers detector repair service. If the detector is damaged by improper handling or exploitation, then this damage is not covered by ACST warranty and reparation costs should be charged to the customer. Usually these do not exceed 3.5k€.

ACST Quasi-Optical Detectors are packed in antistatic bag and aluminium boxes, which protect detector modules from ESD and mechanical shocks during transportation and at customer facility. User guide with description of typical detector performance and operation conditions is included in the box.

Application Areas:


  • THz-Imaging Systems
  • Fast THz Screening
  • THz Spectroscopy

Application Areas:


  • THz-Imaging Systems
  • Fast THz Screening
  • Monitoring of Short THz Pulses
  • Measurements in Synchrotron Accelerators