A laboratory demonstrator of the optoelectronic sensor employing cavity enhanced spectroscopy has been designed to detect the trace amounts of carbon monoxide. High sensitivity of this sensor is provided by the use of optical cavity consisted of dielectric mirrors with extremely high reflectance. The instrument concept was taking into consideration the latest achievement of optoelectronic technology as a part of the ‘EDEN’ project, funded by the Polish National Centre for Research and Development. Preliminary tests using the sensor concept have shown that detection of carbon monoxide is possible using the developed devices. In this configuration, the sensor is characterized by high linear sensitivity in the concentration range of 10 ppb to 2.5 ppm.
The article describes an application one of the most sensitive optoelectronic method – Cavity Enhanced Absorption
Spectroscopy in investigation of nitric oxide in exhaled breath. Measurement of nitric oxide concentration in exhaled
breath is a quantitative, non-invasive, simple, and safe method of respiratory inflammation and asthma diagnosis. For
detection of nitric oxide by developed optoelectronic sensor the vibronic molecular transitions were used. The
wavelength ranges of these transitions are situated in the infrared spectral region. A setup consists of the optoelectronic
nitric oxide sensor integrated with sampling and sample conditioning unit. The constructed detection system provides to
measure nitric oxide in a sample of 0-97% relative humidity.
The article describes an application of cavity enhanced absorption spectroscopy for nitric oxide and nitrous oxide
detection. Both oxides are important greenhouse gases that are of large influence on environment, living organisms and
human health. These compounds are also biomarkers of some human diseases. They determine the level of acid rain, and
can be used for characterization of specific explosive materials. Therefore the sensitive detectors of these gases are of
great importance for many applications: from routine air monitoring in industrial and intensive traffic areas, to detection
of explosives in airports, finally for medicine investigation, for health care, etc.
Our compact detection system provides opportunity for simultaneous measure of both NO and N2O concentration at ppb
level. Its sensitivity is comparable with sensitivities of instruments based on other methods, e.g. gas chromatography or
The paper presents a model of a free space optical transmitter operating in the wavelength range of 8-12 μm. In the
transmitter, a quantum cascade laser controlled by a special driver was applied. The driver provides the control of the
energy, repetition rate and duration of radiation pulses. In the described transmitter, generation of pulses with high duty
cycle is also provided, making it possible to use the data link with either RZ or NRZ coding. In the frame of the study,
the impact of laser working conditions on the data link operation was determined.
The paper presents an application of an optical parametric generator (OPG) for cavity enhanced absorption spectroscopy
(CEAS) technique to nitric oxide (NO) detection. The principle of this method is based on an injection of a radiation
beam into an optical cavity at a very small angle. The radiation is multiple reflected inside the resonator equipped with
spherical and high reflectance mirrors. After each reflection a part of the radiation leaves the optical cavity due to
residual transmission of mirrors. In the case of NO detection the laser emitting at around 5.26 μm was applied. During
investigation of CEAS system with OPG, two-lenses collimator was required to improve OPG beam divergence. The Ge
and ZnSe lenses were used. Thanks to this decrease of about three times in beam diameter was achieved (at the distance
of 1 m from source). It make it possible to measure output signal from the CEAS optical cavity.