Fernando Lopez

University Carlos III de Madrid | UC3M · Department of Physics

Exploring life conditions on the near-Earth planets and satellites before carrying out human missions is an important task for Space Agencies. For that purpose, scientific space missions usually include instruments to measure climatological variables. Within this space instrumentation and measurement context, dust sensors aim to measure dust partic...

The need to monitor specific areas for different applications requires high spatial and temporal resolution. This need has led to the proliferation of ad hoc systems on board nanosatellites, drones, etc. These systems require low cost, low power consumption, and low weight. The work we present follows this trend. Specifically, this article evaluate...

The Short and Mid Wave InfraRed (S-MWIR) rugged active detection system has been designed to be operated in the worst conditions with very low Size Weight and Power (SWaP) factor. The detection system is based on a single uncooled detector device implementing a Lead Sulphide (PbS) (SWIR) and Lead Selenide (PbSe) (MWIR) plate cells on the same packa...

The Japanese Experiment Module-Extreme Universe Space Observatory (JEM-EUSO) telescope will measure ultrahigh-energy cosmic ray properties by detecting the UV fluorescence light generated in the interaction between cosmic rays and the atmosphere. Therefore, information on the state of clouds in the atmosphere is crucial for a proper interpretation...

A fire resistance test, as performed on plates of carbon fibre reinforced polymer composites, is conceptually analogous to a step heating, and can be modelled by the one-dimensional heat equation. Thus modelled, the plate operates as a linear system with an impulse response function that relates temperatures at the front face (the one exposed to fi...

Nowadays, determining the temperature of flames is a challenging measurement in industry. The EMPIR project 14IND04 EMPRESS, in its WP4, address these temperature measurements. The Infrared Lab at the Physics Department of Universidad Carlos III of Madrid (UC3M) has developed a technique for measuring the temperature of a standard flame, in collabo...

Full-Text online view version: http://rdcu.be/ncKw - Abstract: A novel non-intrusive measurement system based on quantitative infrared imaging has been designed and developed specifically for the study of composite plates submitted to fire. The system consists of two synchronised infrared cameras that image both sides of the sample during a fire test,...

The Extreme Universe Space Observatory on board the Japanese Experiment Module of the International Space Station, JEM-EUSO, is being designed to search from space ultra-high energy cosmic rays. These are charged particles with energies from a few 1019 eV to beyond 1020 eV, at the very end of the known cosmic ray energy spectrum. JEM-EUSO will also...

Space-based detectors for the study of extreme energy cosmic rays (EECR) are being prepared as a promising new method for detecting highest energy cosmic rays. A pioneering space device – the “tracking ultraviolet set-up” (TUS) – is in the last stage of its construction and testing. The TUS detector will collect preliminary data on EECR in the cond...

The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) on board the International Space Station (ISS) is the first space-based mission worldwide in the field of Ultra High-Energy Cosmic Rays (UHECR). For UHECR experiments, the atmosphere is not only the showering calorimeter for the primary cosmic rays, it is an essenti...

Cloud parameters such as the Cloud Top Height (CTH), Cloud Top Temperature (CTT), emissivity, particle size and optical depth have always been matter of interest for the atmospheric community. Particularly the CTH provides information leading to better understand the cloud radiative effects. Although there are many meteorological satellites providi...

EUSO-Balloon is a pathfinder for JEM-EUSO, the Extreme Universe Space Observatory which is to be hosted on-board the International Space Station. As JEM-EUSO is designed to observe Ultra-High Energy Cosmic Rays (UHECR)-induced Extensive Air Showers (EAS) by detecting their ultraviolet light tracks “from above”, EUSO-Balloon is a nadir-pointing UV t...

Ultra high energy photons and neutrinos are carriers of very important astrophysical information. They may be produced at the sites of cosmic ray acceleration or during the propagation of the cosmic rays in the intergalactic medium. In contrast to charged cosmic rays, photon and neutrino arrival directions point to the production site because they...

Mounted on the International Space Station(ISS), the Extreme Universe Space Observatory, on-board the Japanese Experimental Module (JEM-EUSO), relies on the well established fluorescence technique to observe Extensive Air Showers (EAS) developing in the earth’s atmosphere. Focusing on the detection of Ultra High Energy Cosmic Rays (UHECR) in the de...

The main goal of the JEM-EUSO experiment is the study of Ultra High Energy Cosmic Rays (UHECR, 1019−1021e V), but the method which will be used (detection of the secondary light emissions induced by cosmic rays in the atmosphere) allows to study other luminous phenomena. The UHECRs will be detected through the measurement of the emission in the ran...

The Extreme Universe Space Observatory (EUSO) on–board the Japanese Experimental Module (JEM) of the International Space Station aims at the detection of ultra high energy cosmic rays from space. The mission consists of a UV telescope which will detect the fluorescence light emitted by cosmic ray showers in the atmosphere. The mission, currently de...

Mars MetNet Mission is a collaborative project involving research groups of Finland, Russia and Spain, with the aim of providing a network of several tens of atmospheric stations along the Martian surface. MEIGA-MetNet payload is the Spanish contribution to this mission, where an extensive atmospheric science payload onboard a lander with restricti...

Cloud information is extremely important to correctly interpret the JEM-EUSO telescope data since UV radiation coming from the Extensive Air Shower can be partially absorbed or reflected by clouds. In order to observe the atmosphere and clouds in the field of view of the UV telescope the JEM-EUSO system will include an Atmospheric Monitoring System...

Clouds interact with the radiation propagating through the atmosphere absorbing, reflecting and transmitting part of the energy. This interaction may lead to misinterpretation of data retrieved from the radiation observed by JEM-EUSO UV telescope. JEM-EUSO Mission includes an Atmospheric Monitoring System (AMS), consisting of a LIDAR and an IR Came...

Infrared (IR) active thermography has been successfully used for non-invasive thermal parameters determination and is fostering significant industrial outcomes in new materials development, quality control, safety, manufacturing processes efficiency, etc. A new approach for thermal parameters characterization, adapted from the standard flash method...

In this work, a methodology based on the combined use of a multilayer perceptron model fed using selected spectral information is presented to invert the radiative transfer equation (RTE) and to recover the spatial temperature profile inside an axisymmetric flame. The spectral information is provided by the measurement of the infrared CO2 emission...

The Extreme Universe Space Observatory (EUSO) is an astronomical telescope that will be hosted by the Japan Experiment Module (JEM) on the International Space Station. The telescope will determine ultrahigh-energy cosmic ray properties by measuring the UV fluorescence light generated in the interaction between the cosmic rays and the atmosphere. Th...

A tool for the virtualization and prediction of thermal behavior of composite materials exposed to fire has been developed. The software, called “3D FireSimulator”, is an interface running above a standard finite element program with a heat transfer module. The 3D FireSimulator (3DFS) is based on the research carried out by the LIR-Infrared Lab of...

The Extreme Universe Space Observatory (EUSO) is an astronomical telescope that will be hosted by the Japan Experiment Module (JEM) on the International Space Station (ISS). The telescope will determine Ultra High Energy Cosmic Rays properties by measuring the UV fluorescence light emitted by the particles generated in the interaction between the c...

Infrared (IR) lock-in thermography (LIT) has been successfully used for defect detection in solar cells. Depending on the experimental setup, defects such as shunts, series resistances, pre-breakdown regions, etc., can be qualitatively visualized or quantitatively measured. IR-LIT results improve the spatial resolution (SR) in defect visualization...

A new procedure adapted from the classical one performed by Parker et al. has been developed to extend it to insulating plates (carbon fiber-reinforced composites). The measurement system consists of an infrared camera synchronized with a flash lamp. This method has been implemented to obtain the thermal parameters of the samples in different state...

An Atmospheric Monitoring System (AMS) is mandatory and a key element of a space-based mission which aims to detect Ultra-High Energy Cosmic Rays (UHECR). JEM-EUSO has a dedicated atmospheric monitoring system that plays a fundamental role in our understanding of the atmospheric conditions in the Field of View (FoV) of the telescope. Our AMS consis...

We evaluate the exposure during nadir observations with JEM-EUSO, the Extreme Universe Space Observatory, on-board the Japanese Experiment Module of the International Space Station. Designed as a mission to explore the extreme energy Universe from space, JEM-EUSO will monitor the Earth's nighttime atmosphere to record the ultraviolet light from tra...

We evaluate the exposure during nadir observations with JEM-EUSO, the Extreme Universe Space Observatory, on-board the Japanese Experiment Module of the International Space Station. Designed as a mission to explore the extreme energy Universe from space, JEM-EUSO will monitor the Earth's nighttime atmosphere to record the ultraviolet light from tra...

There are two main agents that govern surface temperature and the heat transfer process in the Martian atmosphere: CO2 and suspended dust. Dust is a major agent of atmospheric motions at all scales and has great influence on the morphological evolution of the Martian surface and its climate. The flight model (FM) of the current Dust Sensor (DS) of...

A micro-sensor for the characterization of airborne dust in the Martian atmosphere has been designed as a part of Met Net space Mission under strict conditions in mass (<45 g) and power (1 W). Basic physical properties of dust are still poorly known mainly because the usual instruments for dust characterization are located onboard on orbiters and a...

Cosmic Ray physics is one of the fundamental key issues and an essential tool of Astroparticle Physics that aims, in a unique way, to address many fundamental questions of the non-thermal Universe in the Astroparticle Physics domain. The huge physics potential of this field can be achieved by an upgrade of the performance of current ground-based in...

Martian atmosphere contains two main mechanisms leading the heat transfer process: CO2 and suspended dust. The flight model (FM) of the current Dust Sensor (DS) of the Mars MetNet Mission has already been fabricated providing only with the ability for measuring the particle size distribution. The optimized DS proposed in this work includes two sub-...

JEM-EUSO is a space observatory that will be located on-board the Japanese Experiment Module at the International Space Station. It will observe Extensive Air Showers (EAS) induced by ultra-high energy cosmic rays using the Earth's atmosphere as detector. In addition to clear sky observations, EAS are also observable in cloudy conditions if a suffi...

Martian atmosphere contains a significant and rapidly changing load of suspended dust that never drops to zero. The main component of Martian aerosol is micron-sized dust thought to be a product of soil weathering. Although airborne dust plays a key role in Martian climate, the basic physical properties of these aerosols are still poorly known. The...

Contributions of the JEM-EUSO Collaboration to the 32nd International Cosmic Ray Conference, Beijing, August, 2011.

The effect of fire exposure on the thermal behavior of carbon fiber reinforced (CFR) composite plates has been studied. Samples have been exposed to fire produced by a standard burner. The temperature evolution of both faces of the sample has been recorded by a two-camera system providing co-referenced and synchronized images. The camera imaging th...

A FTIR spectroradiometer working in a short open-path configuration has been implemented coupled to a Mass Loss Calorimeter to measure in situ and simultaneously the concentrations of the main gaseous carbon-related by-products from the combustion of forest fuels. A proper methodology to retrieve accurate values of CO and CO2 concentrations has bee...

Fire resistance tests are commonplace in industry. The aerospace sector is particularly active in this area, since the behaviour of advanced materials, such as composites, when in a fire is not fully understood yet. Two of the main obstacles are the inherent difficulty of direct surface measurements in such a harsh environment (especially on the ex...

In this work an adapted bench-scale Mass Loss Calorimeter (MLC) device is used to measure HRR for forest fuels. The MLC has the same heating unit as a standard cone calorimeter, but a) the physical basis to measure HRR in a MLC (by using a calibrated thermopile) is different than the one used in the standard cone calorimeter (oxygen consumption met...

Infrared (IR) imaging is a standard technique in forest fire detection. In previous works we have shown that it can be used to classify the fire scene into regions (of embers, flame, fire front, etc). However, this requires multi-spectral images and a complex post-processing. In this paper we show that a less precise but still powerful classificati...

Design considerations for a temperature sensor to be launched onboard the space mission MetNet precursor to Mars are presented. An IR multispectral sensor has been proposed to measure Martian surface temperature to an accuracy of plusmn1 K without knowing ground emissivity. Two methods for temperature retrieval have been assessed, both relying on c...

During the plastic deformation of metals, part of the mechanical energy is retained in the material as plastic deformations and the rest is converted to heat. A temperature increment is a measure of the heat energy generated in the tested specimen. This temperature can be detected by measuring the infrared (IR) radiation emitted by the specimen sur...

This paper presents the result of a work orientated to the spectral optimization of the acquisition devices in vascular biometrics systems. Spectral windows are proposed which will allow to design a multispectral system with a few and well defined bands, obtaining a more robust and reliable device, compared with the standard single band systems. Th...

In the last years, infrared (IR) cameras have been used increasingly in forest fire related applications, but, in contrast with industrial applications of IR thermography, quantitative studies are almost nonexistent. This is due to the complex spectral and spatial structure of the IR emission that prevents a straightforward interpretation of images...

Accurate determination of gas concentration emitted during thermal degradation (pyrolysis) of biomass in forest fires is one of the keypoints in recent research on physical-based fire spread models. However, it is a very cumbersome task not well solved by classical invasive sensors and procedures. In this work, a methodology to use open-path Fourie...

The analysis of FTIR spectra is usually carried out by commercial programs that use methods based on classical least-squares (CLS) procedures These procedures are normally appropriate to analyse O-P FTIR spectra, but some occasional discrepancies with standard extractive methods have been observed.In this work, a line-by-line method (SFIT) is addit...

Infrared (IR) imaging is a standard technique for the detection of forest fires but its use to measure the physical parameters of fires faces difficulties due to their spatial and spectral complexity. Multi-spectral images in the Medium IR make possible to classify the scene in different fire regions, thus enabling a region-specific processing and...

Fourier Transform Infrared (FTIR) spectroscopy is a well-established technique for monitoring air pollutants by extractive methods. Remote sensing by Open-Path FTIR technique incorporates the advantages of a non-intrusive technique. EPA and VDI have recommended some guidelines for the application of this promising technique. However, it is necessar...

Infrared cameras are well established as a useful tool for fire detection, but their use for quantitative forest fire measurements faces difficulties, due to the complex spatial and spectral structure of fires. In this work it is shown that some of these difficulties can be overcome by applying classification techniques, a standard tool for the ana...

One of the main problems related to infrared remote sensing of forest fires by automatic systems concerns the rejection of false alarms. The study of the infrared spectral radiance emitted by a biomass fire has been used to define spectral algorithms that permit to separate fires from other sources considered as false alarms. The different behaviou...

The new generation of dedicated satellites for remote sensing of forest fires now in advanced development demands validation measurements from airborne platforms. A digital image acquisition system in the medium infrared (MIR) and thermal infrared (TIR) bands has been set up specifically for imaging of fires. The system provides simultaneous, co- r...

The new generation of dedicated satellites for remote sensing of forest fires now in advanced development demands validation measurements from airborne platforms. A digital image acquisition system in the medium infrared (MIR) and thermal infrared (TIR) bands has been set up specifically for imaging of fires. The system provides simultaneous, co- r...

Background (BG) variability is an important issue in fire detection. Due to atmospheric situations in general a high correlation can be assumed between the BG infrared radiation for spatially near zones. This correlation can be even greater if similar forest and soil-surface conditions exist in these zones. In this paper we present an approach for...

Early remote sensing of forest fires from specifically dedicated low cost satellites has recently been proposed as one of the most promising techniques for the improvement in the efficiency of forest fire fighting on a global basis. Efficient forest fire remote sensing requires a high probability of detection for small fires combined to a low false...

The proposed sensor is a new application of the well-known ratiometric techniques to photoconductor array. In this case, the sensor is a photoconductor multiplexer array of 64×4 pixels that covers a sector area 5 km range by 20° azimuth. The proposed system is an automatic and autonomous staring system with only one fixed lens and no mobile parts i...

Information from a ground-based passive remote-sensing system that measures ozone profile concentrations with a moderate 4-cm(-1) spectral resolution is evaluated. A theoretical study of the best choice for the wave numbers and zenith angles for the line of sight is presented. The superimposed water emission is analyzed for the selected wave number...

The array proposed in this paper improves the characteristics of standard infrared arrays for remote sensing, in particular, of those used for incipient forest fires detection. The consequences are of interest mainly in staring non-imaging, large-range, large field of view and low cost-sensors. Furthermore, non-uniformity effects in the focal plane...

Road traffic is one of the most important contributors to air pollution, being that a small fraction of the running vehicles is responsible for more than a half of the emissions. Roadside emission monitoring of individual cars appears to be an efficient way to identify these gross polluters. In this sense, nondispersive infrared (NDIR) systems have...

An IR absorption system for real-time measurement of pollutants in exhaust gases from moving vehicles is proposed. The system consists of an IR source at one side of the road, and a wheel with specific IR filters and a detector at the other side. We have, firstly, simulated the expected exhaust gases concentrations at different inspection condition...

Radiometric characterization of the infrared emission of forest fires has been performed for different primary carriers (grass, shrub, and slash) and different ambient conditions in a combustion tunnel (temperature, relative humidity and wind speed). Fourier Transform-based FTIR spectroradiometer (2.2 - 18 micrometer range) as well as a thermal cam...

This paper describes some of the work performed in the course of the design and development of a new IR sensor system for early detection of forest fires. The proposed device is a non- imaging sensor that would discriminate angular position by means of a simple IR array, working in the 3 - 5 microns wavelength region, placed at the focal plane of t...

PbSe Linear arrays have been fabricated to be used as multiple IR gas sensors at room temperature. PbSe layers were obtained by thermal evaporation in vacuum on SiO2/Si wafers. Samples became photoconductive after a sensitization process that includes thermal treatments in an iodine-enriched atmosphere. Both morphological features and chemical comp...

We study a new kind of environmental compact infrared sensors. These sensors combine a new kind of infrared multilayer filter, solid state Fabry-Perot filters, with narrow bandpass IR optical filters and a pyroelectric detector array. This general goal is obtained by means of three different items: study of infrared parameters of pyroelectric mater...

Infrared imaging of CO in combustion environments is made difficult by cross-talk effects due to the high emission of CO2. A new method for discriminating CO emission, to be implemented in thermal cameras, is proposed. This method is based on a new family of infrared multilayer filters, denominated solid-state Fabry–Pérot (SSFP) filters. The design...

In this work, a new spectral selection system for imaging of CO infrared emission in combustion environments is proposed. The CO and CO2 medium infrared emission bands are spectrally overlapped, so cross-talk effects would appear when trying to image CO using a IR camera equipped with a conventional band-pass filter. The system proposed belongs to...

Commercial Fourier transform based FTIR spectroradiometers can be used in an easy way as ground-based remote sensing systems. Information of the ozone column can be obtained from the spectral IR radiance in the 900-1200 cm-1 range. Tropospheric and stratospheric ozone are sounded by an appropriate selection of the experimental conditions. A theoret...

A new Fabry-Perot filter based on a silicon wafer spacer is proposed in this work. IR gas sensors based on these filters would combine excellent selectivity and signal-to-noise ratio with an overall scheme similar to that of the simplest non-dispersive IR sensors. The filter can be fitted to the fine structure of different gases, in particular thos...

A new sensor is proposed combining arrays of interference filters with resonant cavities of high interference order (Fabry-Perot resonators) using both, high capabilities of accurate thickness control in silicon substrates derived from microelectronics and thin-film optics techniques. The interest of this type of device would be the fabrication of...

Progress in a new electrooptical compact gas sensor system is reported. The sensor measures pollutant concentrations in the atmosphere by comparing the absorption of infrared light in a gas cell at specific wavelengths. This task is performed by a non-dispersive spectral analyzer that operates at discrete wavelengths and has no moving parts (spectr...

One of the widest used methods among the non-dispersive IR (NDIR) low-concentration gas sensors is the gas correlation filter. The optical principle uses a gas ampoule, filled with a known concentration of the gas to be measured, which is introduced in the IR light path by means of a rotating wheel. This gives a reference channel. The wheel also co...

The integration of different infrared interference filters on a single substrate to obtain filter arrays is discussed. These arrays, when coupled in the focal plane to linear photodetector arrays, form the so-called `spectral retinae' which permit spectral and spatial resolution with no moving parts. Its application to new multigas sensors based on...

The concept, design and present stage of development of a new type of electrooptical gas sensor system, with application to the simultaneous detection of several atmospheric pollutant gases, is described. The sensor system is based on non-dispersive infrared differential optical absorption spectroscopy. Spectral analysis is performed by a sensor de...

Ferroelectric materials like lead calcium titanate ceramics have been demonstrated to be excellent materials for pyroelectric detectors. They are usually covered with electroded black gold. This material is extensively used to obtain both a fair IR absorption and a good electrical contact. Spectrally selective compact IR sensors for specific applic...

The integration process of different thin-film interference filters on a unique substrate to give multispectral filter arrays has been studied. Filter arrays properly combined with detector arrays would permit the obtention of multispectral integrated sensors or retinas with spatial and spectral resolution, possibly in the focal plane of a staring...

Infrared focal plane arrays (IRFPA) for staring imaging applications are now in advanced research and development stages. They offer spatial resolution in the focal plane. If spectral resolution is also required as for spectroscopic or analytical applications, a wavelength selection device is needed. The planar integration of different infrared int...

A new system to improve greatly the characteristics of actual infrared (IR) sensors is proposed. The main characteristic of the system is its capability to integrate, on the same substrate, different thin-film optical filters with defined geometries for obtaining arrays of optical filters. This concept would make feasible multispectral integrated s...

A novel system for improving the performance of lead calcium titanate (PCT) ceramics for infrared sensor applications is proposed. The main feature of the system is its ability to integrate, on the same substrate, different thin-film optical filters with defined geometries, in order to obtain arrays of optical filters. Each point on the substrate w...

Resumen Las cámaras infrarrojas son cada vez más utilizadas en la detección y seguimiento de incendios forestales desde tierra. Sin embargo, su alta sensibilidad las hace propensas a falsas alarmas. Este inconveniente puede en principio superarse usando información espectral. En este trabajo se muestra cómo una cámara de infrarrojo medio, dotada de...

In the last years, infrared cameras have been used increasingly in forest fire related applications. They provide information of unique spatial and temporal resolution, but the standard methods of thermography may give erroneous results due to the complex spectral structure of the IR emission of fire. In this work, a two-band imaging system, operat...