Our terahertz imaging camera is a perfect tool for TDS and FDS beam profile measurement which was proved jointly by TERASENSE and TOPTICA researchers in the course of our R&D project followed by technical meeting held at TOPTICA’s headquarters in Munich, March 19-20, 2015.
We are absolutely confident, the results obtained in the course of this mutually enriching collaboration mark the advent of an entirely new era in the development of TDS and FDS systems - now reinforced with TERASENSE imagers.

 

Terahertz time-domain spectroscopy (THz-TDS)

Terahertz time-domain spectroscopy is a spectroscopic technique in which the properties of a material are probed with short pulses of terahertz radiation. The generation and detection scheme is sensitive to the sample material's effect on both the amplitude and the phase of the terahertz radiation. Pulsed terahertz radiation is generated by photoconductive switches (GaAs or InGaAs/InP) irradiated by femtosecond lasers. At the end, a fact Fourier transform of terahertz amplitude produces the terahertz spectrum in the frequency range 0.1 – 5 THz.

Test of TeraSense camera operation with TDS system

50 GHz – 0.7 THz frequency range 1.5 x 1.5 mm2 pixel size 1 nW√Hz noise equivalent power Up to 50 frames per second 16x16, 32x32, 64x64 total pixel models	Fiber-coupled InGaAs photoconductive switches 0.1 – 5 THz bandwidth >90 dB peak dynamic range Average power 25 uW 100 MHz pulse repetition rate

Terahertz frequency-domain spectroscopy (THz-FDS)

Terahertz frequency-domain spectroscopy is a spectroscopic technique in which the properties of a material are probed with continuous-wave (cw) terahertz radiation. The radiation is obtained by optical heterodyning in high-bandwidth photoconductors: the output of two cw lasers converts into terahertz radiation, exactly at the difference frequency of the lasers. The photomixer is represented by a microscopic metal-semiconductor-metal structure. Applying a bias voltage to the semiconductor structure then generates a photocurrent that oscillates at the beat frequency. The output frequency spans from 50 GHz up to 1.5 THz.

Test of TeraSense camera operation with TDS system

50 GHz – 0.7 THz frequency range 1.5 x 1.5 mm2 pixel size 1 nW√Hz noise equivalent power Up to 50 frames per second 16x16, 32x32, 64x64 total pixel models

InGaAs photomixer with bow-tie antenna 0 – 1.2 THz THz scan range Frequency accuracy 2 GHz absolute, 10 MHz relative Power 48 uW (100 GHz), 4 uW (500 GHz) Up tp 100 GHz/s tuning rate