Infrared Imaging Device Research Articles

Internet of things infrared imaging device for assessing lameness in racehorses

Lameness is a clinical condition that heavily affects racehorses. As a result, their competitive performance is dramatically deteriorated and side effects such as changes in feeding patterns may manifest. Within this work we have presented a developed portable Internet of Things (IoT) infrared imaging device, whose application is aimed towards on-site farm level detection of lameness in equine. Additionally we have presented an in-debt review of the causes of lameness, the underlying biological changes that it induces, its influence over tissue thermal patterns and how exercise affects a racehorse's temperature profile.

(Invited) Surface State Modulation of Colloidal Quantum Dots and Construction of Quantum Dot Based Infrared Detectors

Near-infrared photodetection and imaging devices play an important role in fields such as biological detection, information communication, military meteorology, etc. Traditional imaging devices require integration with readout circuits, and the complex integration process limits the development of infrared imaging systems. Lead sulfide colloidal quantum dots have excellent photoelectric properties in the infrared region, with a tunable bandgap width ranging from 0.4 to 1.5 eV, and spectral response covering below 2400 nm. Lead sulfide quantum dot films exhibit high absorption coefficients in the infrared region and excellent carrier mobility. In recent years, the performance of infrared detectors based on quantum dot systems has rapidly improved, and they are expected to develop into a new type of infrared detection and imaging technology. The speaker's team has combined infrared quantum dots with visible light quantum dots to prepare a simple, low-cost, and efficient infrared upconversion imaging device. By using the method of inducing band bending through interface electron storage, the efficiency of carrier tunneling and photon conversion has been improved, and the application of this technology in biological imaging has been preliminarily demonstrated. This report will introduce the development of quantum dot infrared detection materials and devices in recent years, as well as the research progress of the speaker's team in this area.

Vein Visualization With a Near Infrared Imaging Device and Its Impact on Students' and Nurses' Skills in an Academic Teaching University Hospital.

Venipuncture for blood collection is frequently delegated to medical or nursing students, while their individual skills depend on the quality of teaching. The aim of this study was to evaluate the use of a near infrared imaging (NIR) system on the visualization of veins and its potential benefit for the education of medical personnel. Participants answered a questionnaire following standardized venipuncture for blood sampling with the help of an NIR device. Vein visibility with the NIR device and its ability to facilitate venipuncture were examined. Visibility of veins was significantly better with the NIR, and its direction was clearly delineated. Sixty-nine percent of the participants stated that they felt more secure with venipuncture after using the NIR device. Patients' individual factors limited the visibility of veins. The adjuvant use of an NIR system for venipuncture improves participants' subjective skills through visualization of veins and their direction.

Towards Automation of Subsurface Defects Detection in Composites Through Analysis of Thermal Images Using a Hybrid Approach

Active thermal imaging has been attracting a lot of interest as a promising non-destructive technique since it allows the detection of subsurface defects in composites, as well as in other materials. Thermal images captured using this inspection method enable the visualization and localization of structural defects existing within a material. However, determining whether a feature captured in thermal images corresponds to structural defect is not always straightforward, it depends on an inspector’s experience. There is the need to automate the interpretation of thermal image datasets to enhance detection, identification’s accuracy and expedite the inspection of components in several industries making used of thermal imaging methods. Herein, it is described the development of an automated subsurface defect detection system which makes use of a hybrid approach based on two models: a neural network based deep learning model and a signal processing method making use of thermal transport characteristics in solids. This complementary approach aims to reduce the identification of false positives as well as to provide a reliable identification of structural defects based on the thermal properties of composites. The implementation of the defect detection system into a portable infrared imaging device is also discussed.

An infrared thermographic analysis of the sensitization acupoints of women with primary dysmenorrhea.

To explore the sensitization acupoints of women with primary dysmenorrhea (PD) by comparing infrared radiation temperatures between acupoints and non-acupoints. We tested 10 acupoints of every woman with PD and healthy subjects on premenstrual, menstrual, and postmenstrual days using an infrared imaging device. The primary outcome was the absolute value of body surface temperature difference (AVTD) between the left and right sides of the same testing point. A total of 58 PD patients and 57 healthy volunteers completed the test from May 2016 to May 2017. Compared with the healthy group, we observed a significant reduction and increase in the AVTD in Taichong (LR3) and Sanyinjiao (SP6), respectively, during menstrual days in the PD group (= 0.01; = 0.04); while during postmenstrual days, all AVTDs of Shuiquan (KI5), Diji (SP8), and Xuehai (SP10) were diminished in the PD group (= 0.01; = 0.03; = 0.01, respectively). No significant differences in AVTD were detected at any other points or testing times. Compared with the healthy group, the AVTDs of Taichong (LR3), Sanyinjiao (SP6), Shuiquan (KI5), Diji (SP8), and Xuehai (SP10) at menstruation-relevant points of PD patients were sensitized, providing a reference for the selection of acupoints in the treatment of PD.

Uncooled self-powered hemispherical biomimetic pit organ for mid- to long-infrared imaging.

Infrared vision is highly desirable for applications in multifarious fields. Of the few species with this visual capability, snakes have exceptional infrared perception with the assistance of pit organs. Inspired by the pit organ design we present here a hemispherical biomimetic infrared imaging device. The devices use high-density ionic thermoelectric polymer nanowire arrays that serve as the sensing nerve cells. The individual nanowires exhibit notable voltage response to temperature variation in test objects. An infrared sensor array with 625 pixels on the hemispherical substrate is successfully demonstrated with an ultrawide field of view up to 135°. The device can image body temperature objects without a cooling system and external power supply. This work opens up opportunities for the design and fabrication of bioinspired infrared imaging devices based on emerging ionic thermoelectric materials.

Small signal analysis of an infrared imaging device based on equivalent circuit model

This paper presents an analytical model of an infrared thermal imaging device. This device is composed of a Quantum Well Infrared Photodetector (QWIP), a Heterojunction Bipolar transistor (HBT) and a Light Emitting Diode (LED). It is called as QWIP-HBT-LED Optoelectronic Integrated Device. The device is modeled based on its equivalent circuit by considering a nonlinear gain HBT, early effect. Analytical expressions describing the current time response, rise time, and output derivative as a measure of device speed have been derived. The numerical results show that the transient performance of this device version is enhanced by the injected current from QWIP to the base of HBT, also the output current is increased with the increase of the gain and early coefficient of HBT, on the other hand, it degrades when the base recombination factor of HBT or the load resistance is increased. Also, the rise time increases when the current gain or the early coefficient is increased. This type of models can be exploited as a pixel in thermal image processing applications.

Infrared Vein Imaging for Insertion of Peripheral Intravenous Catheter for Patients Requiring Isolation for Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Nonrandomized Clinical Trial

IntroductionEstablishing intravenous access is essential but may be difficult to achieve for patients requiring isolation for severe acute respiratory syndrome coronavirus 2 infection. This study aimed to investigate the effectiveness of an infrared vein visualizer on peripheral intravenous catheter therapy in patients with coronavirus disease 2019. MethodsA nonrandomized clinical trial was performed. In total, 122 patients with coronavirus disease 2019 who required peripheral intravenous cannulation were divided into 2 groups with 60 in the control group and 62 in the intervention group. A conventional venipuncture method was applied to the control group, whereas an infrared vein imaging device was applied in the intervention group. The first attempt success rate, total procedure time, and patients’ satisfaction score were compared between the 2 groups using chi-square, t test, and z test (also known as Mann-Whitney U test) statistics. ResultsThe first attempt success rate in the intervention group was significantly higher than that of control group (91.94% vs 76.67%, ꭓ2 = 5.41, P = .02). The procedure time was shorter in the intervention group (mean [SD], 211.44 [68.58] seconds vs 388.27 [88.97] seconds, t = 12.27, P < .001). Patients from the intervention group experienced a higher degree of satisfaction (7.5 vs 6, z = −3.31, P < .001). DiscussionPeripheral intravenous catheter insertion assisted by an infrared vein visualizer could improve the first attempt success rate of venipuncture, shorten the procedure time, and increase patients’ satisfaction.

Development and application of infrared imaging check and evaluation system

According to the parameters of various kinds of infrared imaging equipment was performance full automatic detection and evaluation of research in this paper. The evaluation system will to accuracy, slit function (SRF), minimum resolvable temperature difference (MRTD), minimum detectable temperature difference (MDTD) and noise equivalent temperature difference (NETD) and other parameters as the basis, the establishment of infrared imaging evaluation system database, to convergence of digital interface to realize automatic detection and evaluation of infrared imaging device, solving the technical problem of performance evaluation of grid infrared imaging equipment, ensure the accuracy of condition based maintenance for power transmission system.

Enhancement Techniques on Medical Thermal Image of Pregnant Women for Fetal Growth Monitoring

ABSTRACT As per the World Health Organization, 94% of all maternal death occurred in low- and middle-income countries. Monitoring foetal heath in these countries is expensive due to the shortage of medical professionals as well as access to facilities. A cost-effective tool for monitoring the foetal growth non-invasively is the need of the hour. One such method is to monitor the skin surface distribution of the abdomen region using an infrared imaging device. The temperature distribution is a physiological response due to the underlying anatomical changes. But, interpretation of this data is qualitative requiring skill and experience. Therefore, there is a need to process the thermal images for quantification for better interpretation with minimum user intervention or expertise. This would help the physician to understand the location of the affected area and its functional disorder to decide on the follow-up treatment. The present research focusses on the enhancement of thermal images using filtering and segmentation techniques. The images were obtained from the abdominal region of pregnant women at various stages of gestation and pregnant with a singleton or twin is processed for enhancement. Histogram method and Otsu thresholding was implemented to augment the image. The correlation was found from the thermal pattern with respect to the foetal gestation period as well as for twin or singleton. Though the sample size is small to confirm this as a stand-alone tool, the results suggest that thermal scanning can be used as a safe and reliable adjunct tool for monitoring foetal growth.

An Automatic Rehabilitation Assessment System for Hand Function Based on Leap Motion and Ensemble Learning

For stroke patients, hand function assessment is an important part of the hand rehabilitation process. The hand function assessment, however, requires the patient to complete a series of actions under the guidance of the therapist who then scores the patient’s performance. This type of assessment is both time-consuming and highly subjective. Therefore, in order to achieve a fast, objective and accurate assessment, this paper adopts a non-contact infrared imaging device, Leap Motion, to measure the patient’s motion information and then uses these motion information to infer the hand’s rehabilitation level. This paper improves the traditional way of hand function assessment from the following aspects. Only three coherent movements (finger opposition, lift wrist and stretch fingers) are required to complete the assessment, which makes the assessment time shorter and the assessment process easier. At the same time, an assessment algorithm based on the Ensemble Learning is proposed and integrated into the automatic hand function assessment system. In addition, the virtual reality game has been implemented in the assessment system to ensure a satisfactory interaction with patients, which makes the assessment process more interesting and convenient. Using this system, 50 stroke patients underwent clinical trials with the Brunnstrom and Fugl-Meyer assessment scales. The matching rate between the automatic assessment result and the manual Brunnstrom assessment result is 92%, while the matching rate with the Fugl-Meyer assessment result is 82%. Furthermore, Wilcoxon Signed-Rank test and Kappa test are also used to validate the consistency between the automatic assessment results and the manual assessment results. These experiments illustrate that this automatic assessment system is fast, comfortable and reliable.

A self-suspended MEMS film convertor for dual-band infrared scene projection

A self-suspended MEMS film convertor used for infrared scene projection was proposed. The film convertor was based on a thin composite film with submicron thickness and high absorption of 95% in visible wavelength range. The microstructure arrays were fabricated by multiple lithography and dry/wet-etching processes to form 1300 × 1300 pixels. By optimizing the geometric parameters of the microstructure, the in-plane thermal diffusion distance was limited to 125 μm. The spatial resolution was therefore improved. Based on this MEMS film convertor, an infrared scene projector was built and its properties were tested. Illuminated by a 532 nm laser, an infrared image with the maximum apparent temperature of 489 K was obtained under the laser power density of 6.4 mW/mm2. By cooling to 278 K, the thermal rising and decay time constants were 5.02 and 2.76 ms, respectively. It indicated that infrared scenes would have a possible frame rate of higher than 100 Hz. The radiation spectrum was similar to a blackbody spectrum, which covered both 3–5 and 8–12 μm wavelength range. These unique properties of the MEMS film convertor made it an ideal candidate to be used in a hardware-in-the-loop simulation system for infrared imaging device performance evaluation.

Experimental investigation on explosion flame propagation of wood dust in a semi-closed tube

In order to explore flame propagation characteristics during wood dust explosions in a semi-closed tube, a high-speed camera, a thermal infrared imaging device and a pressure sensor were used in the study. Poplar dusts with different particle size distributions (0–50, 50–96 and 96–180 μm) were respectively placed in a Hartmann tube to mimic dust cloud explosions, and flame propagation behaviors such as flame propagation velocity, flame temperature and explosion pressure were detected and analyzed. According to the changes of flame shapes, flame propagations in wood dust explosions were divided into three stages including ignition, vertical propagation and free diffusion. Flame propagations for the two smaller particles were dominated by homogeneous combustion, while flame propagation for the largest particles was controlled by heterogeneous combustion, which had been confirmed by individual Damköhler number. All flame propagation velocities for different groups of wood particles in dust explosions were increased at first and then decreased with the augmentation of mass concentration. Flame temperatures and explosion pressures were almost similarly changed. Dust explosions in 50–96 μm wood particles were more intense than in the other two particles, of which the most severe explosion appeared at a mass concentration of 750 g/m3. Meanwhile, flame propagation velocity, flame propagation temperature and explosion pressure reached to the maximum values of 10.45 m/s, 1373 °C and 0.41 MPa. In addition, sensitive concentrations corresponding to the three groups of particles from small to large were 500, 750 and 1000 g/m3, separately, indicating that sensitive concentration in dust explosions of wood particles was elevated with the increase of particle size. Taken together, the finding demonstrated that particle size and mass concentration of wood dusts affected the occurrence and severity of dust explosions, which could provide guidance and reference for the identification, assessment and industrial safety management of wood dust explosions.

Getting Information on Impact Damage of Carbon Fibre-Reinforced Composites from Thermal Signature Evolution

The susceptibility of carbon fibre-reinforced polymers to impact damage is a well-known problem and drives efforts of researchers towards the creation of new materials, which may be able to contrast impact. Being difficult to predict the behaviour of a newly conceived material during the design phase, specific tests are necessary to assess its impact resistance. This is generally obtained through lengthy tests, which, amongst others, are aimed to find a relationship between the impact energy and the size of the produced damage. A fast and relatively cheap way appears to be in-line monitoring of impacts with an infrared imaging device; the obtained information can contribute to enhance the knowledge of impact damage mechanisms. The attention of this paper is mostly focused on post-processing and analysis of thermal images, which were recorded during in-line monitoring of impact tests. The obtained results are compared with the existing literature and a general agreement is found. As important points, from mechanical-coupled thermal effects, it is possible to get information about some characteristic times such as the impact duration and the time at which peak contact force occurs as well as to individuate damage initiation. These findings can be achieved in a remote way, without any contact with the part under investigation and without any interference with the test execution.

A Tissue Expander–like Scaffold With Photothermal Tumor Ablation Property for Breast Tissue Engineering

BACKGROUND: Tissue engineering–based breast reconstruction after mastectomy is a promising alternative to traditional treatments.1,2 Nevertheless, it could so far neither prevent the potential breast cancer recurrence nor solve the problem of covered skin shortage. PURPOSE: Here we reported the construction of a novel breast tissue engineering scaffold. Benefiting from the photothermal effect of graphene, it can ablate breast cancer cells and recover its shape in a tissue expander-like manner. MATERIALS AND METHODS: Different concentrations of graphene nanoparticles (GNs) were used to functionalize the dome-shaped 3-dimensional–printed polyurethane scaffolds (GfS). Subsequently, GfS were remodeled into disk-like temporary shape. Afterward, GfS were exposed to 808 nm laser with different light intensity, the temperature change was captured by infrared imaging device, and the shape recovery rate was measured by vernier caliper. At last, tumor ablation study was performed using MDA-MB-231 cell line in vitro under 808 nm laser photothermal treatment. RESULTS: The scaffolds functionalized with higher concentration of GN displayed higher degree of blackness and higher temperature rising after laser exposure. In addition, light intensity was also positively correlated with the temperature rising. Laser illuminating could trigger the shape recovery of GfS from temporarily disk-like shape toward their original dome shape. The shape recovery ability of GfS is positively correlated with the light intensity. After exposing to 808 nm laser, GfS could ablate the surrounded MDA-MB-231 breast cancer cells in a GN concentration and light intensity–dependent manner. CONCLUSION: After being irradiated by 808 nm laser, the 3-dimensional–printed polyurethane scaffold functionalized with GNs can recover its initial shape in a tissue expander-like manner and ablate the breast cancer cells. This multifunctional scaffold could potentially be used for tissue engineering–based breast reconstruction to address the problem of covered skin shortage and tumor recurrence after mastectomy. REFERENCES: 1. Findlay MW, Dolderer JH, Trost N, et al. Tissue-engineered breast reconstruction. Plast Reconstr Surg. 2011;128:1206–1215. 2. Chhaya MP, Melchels FP, Holzapfel BM, et al. Sustained regeneration of high-volume adipose tissue for breast reconstruction using computer aided design and biomanufacturing. Biomaterials. 2015;52:551–560.

Analytical Modeling of the Temperature Using Uniform Moving Heat Source in Planar Induction Heating Process

The planar induction heating possesses more difficulties in industry application compared with traditional spiral induction coils in mostly heat treatment processes. Numerical approaches are adopted in the power distribution and temperature prediction during the induction heating process, which has a relatively low computational efficiency. In this work, an analytical calculation model of the planar induction heating with magnetic flux concentrator is investigated based on the uniform moving heating source. In this model, the power density in the surface of the workpiece induced by coils is calculated and applied into the analytical model of the temperature calculation using a uniform moving heat source. Planar induction heating tests are conducted under various induction coil parameters and the corresponding temperature evolution is obtained by the infrared imaging device NEC R300W2-NNU and the thermocouples. The final surface temperature prediction is compared to the finite element simulation results and experimental data. The analytical results show a good match with the finite element simulation and the experimental results, and the errors are in reasonable range and acceptable. The analytical model can compute the temperature distribution directly and the computational time is much less than the finite element method. Therefore, the temperature prediction method in this work has the advantage of less experimental and computational complexity, which can extend the analytical modeling methodology in induction heating to a broader application.

Preparation of silver-plated Hollow Glass Microspheres and its application in infrared stealth coating fabrics

The infrared stealth fabric was prepared using silver-plated Hollow Glass Microspheres (HGMs) doped with aluminum powder by coating. Silver-plated HGMs was produced by in-situ polymerization of polyaniline (PANI) firstly and followed by electroless silver plating. The surface morphology was characterized by scanning electron microscopy (SEM). FT-IR and XRD analysis were further carried out to verify the preparation of silver-plated HGMs and coated fabrics during the reaction. Thermal infrared imaging device was used to test infrared radiation intensity of coating cotton fabric. Anti-electromagnetic radiation tester was used to evaluate shielding effectiveness. The surface temperature difference of the heated coating fabric was measured. Thermogravimetric (TG) analysis was carried out to study thermal stability. Only a little temperature rises after heating the coating fabric with low infrared radiation, and the shielding effectiveness (SE) can reach 26.8 dB. The results demonstrated this material was endowed with outstanding infrared stealth, electromagnetic interference (EMI) shielding and thermal radiation protection properties.

Thermal Effect of Oil Tank Heated by External Fire with Influence of Explosion Suppression Materials

ABSTRACTExperimental study of explosion prevention has been performed in the oil tank filled with suppression material. The kerosene in the pool is used as the fuel to ignite the gasoline and diesel oil tank to investigate the impact of suppression material on the degree of the deflagration. The pictorial information and temperature data are recorded by the high-speed camera and infrared imaging device, respectively. The maximum temperature of the fire in the tank within the filling material has apparently declined. The temperature of diesel oil liquid is greater than the diesel oil vapor. On the contrary, the temperature of gasoline vapor will keep arising and surpass the gasoline liquid. In the presence of suppression material, the average rate of temperature rise of the gasoline and diesel oil liquid is about 0.12 and 0.15 K/s, respectively. Damage of heat radiation effects to the human body from different combustion models has been compared with the effect of suppression material.

The contribution of infrared thermography in the characterization of jute based composites

The growing environmental awareness is driving attention towards the development of ever more ecological and friendly materials, calling for the use of natural matrix and fibres in composite materials. The attention of this work is focused on two types of composites, which both include jute as reinforcement but different matrices. One matrix is polypropylene (PP) and the other one is poly-lactic acid (PLA), so to have partial, or total, natural materials. Several specimens are prepared and tested under impact, or cyclic and quasi-static bending. An infrared imaging device is used to in-line monitoring of specimens under each test. The visualization of thermal effects coupled with mechanical stresses allows getting complimentary information, which may be exploited to better understand the reaction of materials to applied forces and their damaging modes.

Electro-thermal analysis of an Al–Ti multilayer thin film microheater for MEMS thruster application

A multilayer thin film aluminum/titanium (Al/Ti) microheater is developed for the microthruster liquid propellant vaporizing and gas heating for increasing the specific impulse. The microheater was fabricated onto a Pyrex 7740 substrate using a Micro-Electro-Mechanical Systems processing technology. A finite-element based multiphysics simulation was employed to simulate the microheater performance. The distribution of temperature and variation of the thermal deformation are simulated in modeling with the different input power. And the simulation shows that heat loss of the microheater is relatively low comparing with the normal heater. Subsequently an experimental testing of the microheater performance based on infrared imaging device was actualized with applied voltage from 5 to 36 V. An auger electron spectroscopy detection was employed to validating the assumption that Al layer oxidizing is the main reason of temperature higher in the test than simulation.