Infrared CCD Camera Research Articles

Soft Tissue Facial Morphology in Growing Patients with Different Occlusal Classes.

The study of facial profiles in the dental field is very important for the diagnosis and the dental and orthodontic treatment plan. The aim of this study is to analyze the three-dimensional morphology of the faces of 269 growing patients with Class I and II occlusions, focusing on children aged between 6 and 9 years old. The analysis was conducted using a non-invasive computerized system, which allowed for the automatic collection of facial landmarks and the subsequent reconstruction of three-dimensional coordinates. The sample comprised 269 children within the specified age range. Each child's facial features were captured using the non-invasive computerized system, which utilized two infrared CCD cameras, real-time hardware for label recognition, and software for three-dimensional landmark reconstruction. Sixteen cutaneous facial landmarks were automatically collected for each participant. From these landmarks, 10 angular and 15 linear measurements, as well as five direct distance rates, were derived. The mean values for each age class were calculated separately for children with bilateral Angle Class I occlusion and compared with those for children with bilateral Class II occlusion. In all children, the left and right occlusal classes were measured as suggested by Katz. The analysis revealed notable differences, primarily in the three-dimensional angular measurements between children with Class I and II occlusions. Specifically, Class II children exhibited more convex faces in the sagittal plane and a less prominent lower jaw compared to Class I children. However, no significant differences were observed in linear measurements, except for the lower facial height rate, which varied inconsistently across age groups between the two occlusion types. the findings of this research highlight distinct three-dimensional facial morphological differences between children with Class I and II occlusions. While Class II children tended to have more convex facial profiles and less prominent lower jaws, linear measurements showed minimal variation between the two occlusion types. These results underscore the importance of three-dimensional analysis in understanding facial morphology in growing patients with different occlusal patterns.

Super Planckian Thermal Radiation Emitted From a Nano-Filament of Photonic Crystal: A Direct Imaging Study

In this paper, we report a direct imaging of narrow-band super Planckian thermal radiation in the far field, emitted from a resonant-cavity/tungsten photonic crystal (cavity/W-PC). A spectroscopic study of the cavity/W-PC shows a distinct resonant peak at λ ~ 1.7 μm. Furthermore, an infrared CCD camera was used to record radiation image of the cavity/W-PC and a carbon-nanotube (CNT) black reference at λ ~ 1.7 μm emitted from the same sample. The recorded image displays a higher brightness emitted from the cavity/W-PC region than from the blackbody region for all temperatures tested, T = 530-650 K. This observation is in sharp contrast to the common understanding of equilibrium thermal radiation, namely, a blackbody has a unit absorptance, a unity emittance and should emits the strongest radiation. Since the image was taken from the same sample and the temperature difference across the W-PC/ CNT boundary is less than 0.1 K, the observed image contrast gives a truly convincing evidence of super Planckian behavior in our sample. The discovery of a super-intense, narrow band radiation from a heated W-PC could open up a new door for realizing narrow band infrared emitters. The W-PC filament could also be very useful for efficient energy applications such as thermo-photovoltaics, waste heat recycling and radiative cooling.

Application of dynamic time warping algorithm for pattern similarity of gait.

The purpose of this study was to investigate the effectiveness of dynamic time warping (DTW) in gait research. Participants in this study were consist of 10 males and 10 females. Equipment used for collecting the gait data of participants in this study was three-dimensional (3D) motion analysis system consisted of 8 infrared CCD cameras operated with a sampling frequency of 120 frames/sec. DTW program used in this study was made using the MATLAB and the normal operation of the DTW program was verified by comparison of result manually calculated and output by the DTW program. Flexion angle of the knee joint of both feet obtained by 3D motion analysis system was analyzed by the DTW program and symmetry index (SI) equation. Statistical analysis of the values obtained by DTW was performed by one-sample t-test in confidence interval (CI) 99%, 95%, 90%, 85%, and 80% each using the SPSS. The subjects’ left and right legs were compared 20 times, and other steps of the same foot were compared 20 times. In this study, DTW showed different results from SI which is generally used to test the similarity of gait. Compared to that of DTW, the threshold figure for similarity evaluation in SI, 10%, is considered too large/high. When the CI threshold figure of 95% was adopted in statistical analysis, DTW demonstrated a lower rate of judging two sequences as similar even in the case of normal gait. This study suggests that DTW can be used for the similarity test of gait research.

Visual-assisted laser microwelding of carbon microfiber on metal plates

The welding scale of laser welding now went to micrometer size. Under the view of optical microscopy, the high-precision laser welding systems can be achieved. But the welding processes were monitored by human eyes, and the light scattering may interfere the observation. We presented a visual-assisted laser microwelding system. This work combined laser microwelding technology, thermal imaging process, and the active feedback control loop to achieve the real-time microwelding quality control. The thermal imaging camera and the near infrared CCD camera were used to monitor the welding process. The active feedback control loop was employed, and linked the thermal distribution of the thermal images with the duty cycle of laser operations. 0.1-s response time can make sure the laser welding under control without manually tuning. So that welding technicians with this optical system can control the quality, improve the production yields, and shorten the whole process time. With this optical system, we successfully welded the carbon strip and tens-of-µm carbon fiber with aluminum plate. It will be useful for soft, and flexible carbon-based electrical devices.

Office-based differential diagnosis of transient and persistent geotropic positional nystagmus in patients with horizontal canal type of benign paroxysmal positional vertigo

Conclusion: A 30 s observation of geotropic positional nystagmus is sufficient to distinguish persistent geotropic positional nystagmus (PGPN) from transient geotropic positional nystagmus (TGPN) in patients with horizontal canal type of benign paroxysmal positional vertigo (H-BPPV) in ENT office.Objective: As a canalith repositioning procedure effectively treats H-BPPV with TGPN, but not PGPN, the differentiation between patients with PGPN and with TGPN is essential. The purpose of this study is to determine the observation period enough to distinguish TGPN from PGPN.Methods: This study first analyzed positional nystagmus images recorded with an infrared CCD camera three-dimensionally in 47 patients with H-BPPV. PGPN is distinguished from TGPN in patients with H-BPPV precisely by means of time constant calculated form analysis of positional nystagmus. Ten-second and 30-s movies were made of positional nystagmus of the all 47 patients. Ten independent otolaryngologists were then asked to distinguish TGPN from PGPN after a 10 s or 30 s observation of the geotropic positional nystagmus images in 47 patients with H-BPPV.Results: The sensitivity and specificity to distinguish TGPN from PGPN was 100% and 97% after 30 s observation, but 100% and 40% after 10 s observation, respectively.

An inverse method for flue gas shielded metal surface temperature measurement based on infrared radiation

The infrared temperature measurement technique has been applied in various fields, such as thermal efficiency analysis, environmental monitoring, industrial facility inspections, and remote temperature sensing. In the problem of infrared measurement of the metal surface temperature of superheater surfaces, the outer wall of the metal pipe is covered by radiative participating flue gas. This means that the traditional infrared measurement technique will lead to intolerable measurement errors due to the absorption and scattering of the flue gas. In this paper, an infrared measurement method for a metal surface in flue gas is investigated theoretically and experimentally. The spectral emissivity of the metal surface, and the spectral absorption and scattering coefficients of the radiative participating flue gas are retrieved simultaneously using an inverse method called quantum particle swarm optimization. Meanwhile, the detected radiation energy simulated using a forward simulation method (named the source multi-flux method) is set as the input of the retrieval. Then, the temperature of the metal surface detected by an infrared CCD camera is modified using the source multi-flux method in combination with these retrieved physical properties. Finally, an infrared measurement system for metal surface temperature is built to assess the proposed method. Experimental results show that the modified temperature is closer to the true value than that of the direct measured temperature.

High-Speed Video-Oculography for Measuring Three-Dimensional Rotation Vectors of Eye Movements in Mice.

BackgroundThe mouse is the most commonly used animal model in biomedical research because of recent advances in molecular genetic techniques. Studies related to eye movement in mice are common in fields such as ophthalmology relating to vision, neuro-otology relating to the vestibulo-ocular reflex (VOR), neurology relating to the cerebellum’s role in movement, and psychology relating to attention. Recording eye movements in mice, however, is technically difficult.MethodsWe developed a new algorithm for analyzing the three-dimensional (3D) rotation vector of eye movement in mice using high-speed video-oculography (VOG). The algorithm made it possible to analyze the gain and phase of VOR using the eye’s angular velocity around the axis of eye rotation.ResultsWhen mice were rotated at 0.5 Hz and 2.5 Hz around the earth’s vertical axis with their heads in a 30° nose-down position, the vertical components of their left eye movements were in phase with the horizontal components. The VOR gain was 0.42 at 0.5 Hz and 0.74 at 2.5 Hz, and the phase lead of the eye movement against the turntable was 16.1° at 0.5 Hz and 4.88° at 2.5 Hz.ConclusionsTo the best of our knowledge, this is the first report of this algorithm being used to calculate a 3D rotation vector of eye movement in mice using high-speed VOG. We developed a technique for analyzing the 3D rotation vector of eye movements in mice with a high-speed infrared CCD camera. We concluded that the technique is suitable for analyzing eye movements in mice. We also include a C++ source code that can calculate the 3D rotation vectors of the eye position from two-dimensional coordinates of the pupil and the iris freckle in the image to this article.

Structure of the runaway electron loss during induced disruptions in TEXTOR

The loss of runaway electrons during an induced disruption is recorded by a synchrotron imaging technique using a fast infrared CCD camera. The loss is predominantly diffuse. During the “spiky-loss phase”, when the runaway beam moves close to the wall, a narrow channel between the runaway column and a scintillator probe is formed and lasts until the runaway beam is terminated. In some cases, the processed images show a stripe pattern at the plasma edge. A comparison between the MHD dominated disruptions and the MHD-free disruption is performed. A new mechanism of plasma disruptions with the runaway electron generation and a novel model which reproduces many characteristic features of the plasma beam evolution during a disruption is briefly described.

同一頭位で2相性眼振がみられた頭位めまい症例

Introduction: In positional vertigo, spontaneous reversal of the initial positional nystagmus (the secondary phase nystagmus) is clinically rare without head position changes. We present herein a case of positional vertigo with the secondary phase nystagmus monitored and video-recorded using an infrared CCD camera. Patient: A 65-year-old woman visited our otorhinolaryngological clinic with rotatory positional vertigo. At the initial visit, upbeat-torsional (counterclockwise) nystagmus induced by the head positional test was observed for>70s, with a latency of 2s; furthermore, the reversal of nystagmus was not observed when the head was moved back to the sitting position. Three days later, downbeat-torsional (clockwise) nystagmus induced by the head positional test was observed for 19s with a latency of 3s, and it was followed by reversal of initial positional nystagmus for 75s without head position changes. Conclusion: The duration of positional nystagmus was>70s, and the reversal of nystagmus was not observed when the head was moved back to the sitting position. Therefore, we speculated that positional vertigo presumably involved canalolithiasis within the short-arm of the posterior canal. Further, we speculated that the secondary phase nystagmus was presumably due to the coexistence of long-arm type anterior canalolithiasis and short-arm type posterior canalolithiasis.

耳鼻咽喉科診療所におけるめまい症例の検討

Introduction: From fiscal year 2011, the Japan Society for Equilibrium Research started a certification system for doctors consulting regarding dizziness, and it is predicted that an increasing number of clinic doctors will be certified as consulting doctors for this purpose in the future. Further, the importance of clinic doctors involved in primary care as consulting doctors for dizziness is anticipated to increase. We investigated vertiginous outpatients who visited our ENT clinic. Subjects: For the 4 years from January 2010 to December 2013, 810 out of 16,903 patients (4.8%) who visited our clinic complained of dizziness. Results: The patients consisted of 239 males and 571 females aged 6-97 years, with a male-to-female ratio of 1: 2.4. Among the 810 patients who visited our clinic with a complaint of dizziness, the presence of nystagmus was examined using an infrared CCD camera in 366 patients (45%), and these patients were diagnosed as having the following conditions: the most common vertiginous disease was benign paroxysmal positional vertigo in 208 (25.7%), followed by other peripheral vestibular disorders in 66 (8.1%) and Meniere's disease in 57 (7.0%). Many of the patients with nystagmus visited our clinic early after the onset of dizziness, and 75.4% of the patients with dizziness visited within seven days after onset.

The design and application of an automatic optical inspection system for the advanced fiber coupler assembly manufacturing process

In this paper an automatic optical inspection system for the advanced fiber coupler assembly manufacturing process is presented. Coupling efficiency variations were compared with axial displacement. The main standard components of light peak fiber couplers were used in the experiment to determine the corresponding offset and position of the optimal optical coupling efficiency in order to achieve a positioning effect. This study used the parameters of lens curvature, focal length and light source for validation using optical design software. An infrared CCD camera was used to extract the coupled light spot images. The curve fitting method and coupling simulation database were used for image processing and to calculate optimal coupling efficiency. Under optimal coupling efficiency, the minimum amount of movement of the translation stages was used to calculate the offset of each axle or the coupling efficiency when tilted. Moreover, a coupling efficiency database was established. The optical axle center offset in the alignment was calculated by comparing the data in the database. Finally, the optical axle center offset or tilt direction was identified through the program to achieve the position of optimal coupling efficiency.

Low Cost, Precision, Passive-Alignment Technique for 100 Gb/s DP-QPSK Receiver

We propose and develop a passive alignment technique of 4 output waveguides of PLC-based 90° OH and a 1×4 PD array. This alignment technique only uses an infrared CCD camera and an infrared light.

Design of Cooling System for Infrared CCD Camera Used to Monitor Burden Surface of Blast Furnace Based on Thermoelectric Coolers

A temperature control system based on thermoelectric coolers is designed in this paper for infrared CCD camera used to monitor burden surface of blast-furnace. The thermoelectric cooling system consists of a microcontroller module, a temperature sensor, a CCD camera, a thermoelectric cooler, a power amplifier and isolation module. The CCD camera with a temperature sensor is tightly mounted on the TEC cold surface. The microcontroller changes duty ratio of PWM signals with changes of the camera temperature to make working temperature of the CCD camera constant. The experiments show that the cooling system works well in temperature controlling

An imaging system for monitoring the in-and-out activity of honey bees

This study aimed to develop an imaging system for monitoring and analyzing the in-and-out activity of honey bees as they pass through the entrance of a beehive. As such, the daily in-and-out activity of a beehive could be automatically recorded with minimum interference with the regular behavior of the bees. The components of the imaging system include: (1) an infrared LED light source; (2) an infrared CCD camera and a personal computer for image acquisition and processing; and (3) an acrylic passageway to temporarily confine the bees within the image-capturing range of the camera. In operation, this imaging system was affixed to the outside of a beehive at the entry/exit point. To identify each forager of bee workers individually, circular character-encoding tags were attached to the dorsum of the bees’ thoraxes. To locate individual honey bees in a video frame, a circular Hough transform was used to detect the presence of the circular tags. A black positioning dot on the tag was used to identify the orientation of the characters in order to facilitate the reading of the symbols on the circular tag. The extracted character symbols were further segmented and a support vector machine (SVM) classifier was deployed to recognize the characters and identify the individual honey bee. The system developed in this study was used in experimentation to identify each of the tagged bees and to record the timing of the entries and exits. The character symbol recognition and identification accuracy rates of the system were about 98% and 86%, respectively. Based on the in-and-out records, daily foraging behavior of honey bees were analyzed and presented. These experimental results demonstrate that this imaging system is feasible and can be used as an efficient tool to study honey bee behavior.

Analysis of postoperative vertigo or dizziness in cochlear implant patients

Cochlear implants (CIs) are associated with a potential risk for vestibular system insult or stimulation with resultant dysfunction. Twenty-six patients underwent equilibrium tests before undergoing CI surgery at our institute. As part of the equilibrium tests, a caloric test, static posturography, observation of nystagmus using an infrared CCD camera, and measurement of the vestibular-evoked myogenic potential (VEMP) were performed. Half of the patients (13 out of 26 patients) complained of vertigo or dizziness after the operation. In most patients (12 out of 13 patients), these symptoms occurred immediately after the operation and disappeared within one week. Patients who did not complain of vertigo or dizziness after the CI surgery had a statistically significant lower response for the caloric testing than the patients who experienced these symptoms. No significant differences in the static posturography, nystagmus and VEMP test results were seen between the group of patients who did not complain of vertigo or dizziness after the CI surgery and the group of patients who experienced these symptoms. This result suggests that the patients with normal peripheral vestibular functions preoperatively had a greater tendency to complain of vertigo or dizziness after the operation. The cause of postoperative vertigo or dizziness was judged to be due to the peripheral vestibular function before surgery. It is important for CI candidates to undergo equilibrium tests preoperatively as means of predicting postoperative vertigo or dizziness.

Rotation vectors of slow and quick phase of caloric nystagmus

The purpose of this study was to elucidate the rotation axes of the slow and quick phase of the caloric nystagmus using the video-oculographic technique. Subjects were placed in a supine position and cold-water stimulation was applied to the right ear canal. The eye movements were recorded in complete darkness by a high-speed infrared CCD camera. The sampling time of the camera was 132Hz with 640×480 effective pixels. The rotation vectors were calculated from the printed-out chart of the 3D analysis data of the caloric nystagmus. The directions of the rotation vector of the quick phase of the nystagmus were almost opposite to those of the slow phase. The average planer equations of the slow and quick phase of the nystagmus in all subjects were 0.399x+0.1477y-0.8656z=0 and -0.3970x-0.1940y+0.8559z=0, respectively. We demonstrated that the slow phase and quick phase of the vestibular nystagmus are along with the same axes in human subjects.

Observation of spontaneous nystagmus with an infrared CCD camera in patients with sudden deafness

Observation of spontaneous nystagmus with an infrared CCD camera in patients with sudden deafness

Near-field and far-field analysis of an azimuthally polarized slow Bloch mode microlaser

We report on the near- and far-field investigation of the slow Bloch modes associated with the Γ point of the Brillouin zone, for a honeycomb lattice photonic crystal, using near-field scanning optical microscopy (NSOM) and infra-red CCD camera. The array of doughnut-shaped monopolar mode (mode M) inside each unit cell, predicted previously by numerical simulation, is experimentally observed in the near-field by means of a metal-coated NSOM tip. In far-field, we detect the azimuthal polarization of the doughnut laser beam due to destructive and constructive interference of the mode radiating from the surface (mode TEM(01*)). A divergence of 2° for the laser beam and a mode size of (12.8 ± 1) µm for the slow Bloch mode at the surface of the crystal are also estimated.

Diagnostic significance and test methods of electronystagmography (ENG)

Electronystagmography (ENG) is an equilibrium function test that records eye movements. Its objectives are to detect asymmetry in peripheral vestibular function and to detect central nervous system disorders. The merits of ENG are as follows: 1) various types of eye movements, including nystagmus, can be recorded; 2) nystagmus can be quantitatively analyzed; and 3) eye movement with the eyes closed and with the eyes open in darkness can be recorded. A weakness of ENG is that while it can record eye movement in the horizontal and vertical directions, it is not capable of recording rotatory eye movements. In clinical practice, ENG is used to detect the following: 1) spontaneous ocular motility in bright light and in the absence of fixation (with the eyes closed and with the eyes open in darkness); 2) gaze nystagmus; 3) positional nystagmus; 4) positioning nystagmus; 5) smooth pursuit; 6) optokinetic nystagmus; 7) saccade; 8) rotatory nystagmus; 9) caloric nystagmus; and 10) visual suppression. ENG can be performed with either binocular or monocular leads, and the latter is used particularly for recording of dysconjugate ocular motility, which occurs with supranuclear ocular motility disorders such as MLF syndrome. Although ENG is being used for diagnosis of dizziness and disequilibrium, we must not place too trust on the results of ENG tests. ENG is only a test of eye movement, and the causal relationship between ENG results and lesions must be determined by the users themselves. Recently, the use of videooculography (VOG) using an infrared CCD camera that also enables recording of rotatory eye movements has gradually spread, while the use of ENG is in decline.

Driver identification using finger-vein patterns with Radon transform and neural network

A driver identification system using finger-vein technology and an artificial neural network is presented in this paper. The principle of the proposed system is based on the function of near infra-red finger-vein patterns for biometric authentication. Finger-vein patterns are required by transmitting near infra-red through a finger and capturing the image with an infra-red CCD camera. The algorithm of the proposed system consists of a combination of feature extraction using Radon transform and classification using the neural network technique. The Radon transform can concentrate the information of an image in a few high-valued coefficients in the transformed domain. The neural networks are used to develop the training and testing modules. The artificial neural network techniques using radial basis function network and probabilistic neural network are proposed to develop a driver identification system. The experimental results indicated the proposed system performs well for personal identification. The average identification rate of PNN network is over 99.2%. The details of the image processing technique and the characteristic of system are also described in this paper.