VOC DETECTIONS WITH OPTICAL SPECTROSCOPY

Spectroscopy, Structural, and Optical Investigations of NiFe2O4 Ferrite

Ni ferrite crystalline material is synthesized using a sol-gel method at two different temperatures. The vibrational and stretching modes, crystalline phase, size distribution and morphology of the products are investigated via Raman back-scattering and Fourier transform infrared (FTIR) spectroscopy, XRD and FESEM, respectively. Vibrational modes of spinel ferrite are observed at Raman and FTIR...

Ultrasensitive Detections of Weak Resonances ─ Application to Optical Frequency Standards

We present our latest results on the ultrasensitive molecular overtone spectroscopy using the cavity-enhanced frequency modulation (FM) technique. The principle of this technique makes use of a high-finesse external cavity to enhance the intrinsic resonance contrast, while an FM modulation approach provides shot-noise limited signal recovery. Working with a 1.064 m Nd:YAG laser, we have obtain...

Skin Lesions Classification with Optical Spectroscopy

Diagnosis of benign and malign skin lesions is currently mostly relying on visual assessment and frequent biopsies performed by dermatologists. As the timely and correct diagnosis of these skin lesions is one of the most important factors in the therapeutic outcome, leveraging new technologies to assist the dermatologist seems natural. Complicating matters is a blood cancer called Cutaneous T-C...

Review of Methods of Optical Gas Detection by Direct Optical Spectroscopy, with Emphasis on Correlation Spectroscopy

Optical frequency comb spectroscopy.

Optical frequency combs offer enormous potential in the detection and control of atoms and molecules by combining their vast spectral coverage with the extremely high spectral resolution of each individual comb component. Sensitive and multiplexed trace gas detection via cavity-enhanced direct frequency comb spectroscopy has been demonstrated for various molecules and applications; however, pre...