2008, 6(12) Column
Chinese Optics Letters 第6卷 第12期
Innovative confocal laser method for exact dioptric power measurement of intraocular lens implantsDownload:513次
We present a novel confocal laser method (CLM) for precise testing of the dioptric power of both positive and negative intraocular lens (IOL) implants. The CLM principle is based on a simple fiber-optic confocal laser design including a single-mode fiber coupler that serves simultaneously as a point light source used for formation of a collimated Gaussian laser beam, and as a highly sensitive confocal point receiver. The CLM approach provides an accurate, repeatable, objective, and fast method for IOL dioptric power measurement over the range from 0 D to greater than +-30 D under both dry and in-situ simulated conditions.
共焦显微 医用光学仪器 眼科 人工晶状体 单模光纤 170.1790 Confocal microscopy 170.4460 Ophthalmic optics and devices 170.3890 Medical optics instrumentation 060.2370 Fiber optics sensors Gold nanoparticles (NPs) have highly efficient multi-photon-induced luminescence. In this paper, we record the two-photon images of gold NPs, lymphoma cell line Karpas 299, and Karpas 299 incubated with 30-nm-diameter gold NPs and ACT-1 antibody conjugates (Au30-ACT-1 conjugates) by using a multi-photon microscopy system. Due to the specific conjugation of ACT-1 antibody and cell membrane receptor CD25, gold NPs are only bound to the surface of cell membrane of Karpas 299. The luminescence intensity of gold NPs is higher than that of cells at 750-nm laser excitation. By comparing the images of Karpas 299 cells incubated with and without gold NPs, it is found that by means of gold NPs, we can get clear cell images with lower excitation power. Their excellent optical and chemical properties make gold NPs an attractive contrast agent for cellular imaging.
170.3880 Medical and biological imaging 170.4580 Optical diagnostics for medicine 300.6410 Spectroscopy, multiphoton Study of van Gieson's picrofuchsin staining on second-harmonic generation in type I collagenDownload:616次
Second-harmonic generation (SHG) microscopy is a recently developed nonlinear optical imaging modality for imaging tissue structures with submicron resolution and is a potent tool for visualizing pathological effects of diseases. In this letter, we present our investigation on the influence of van Gieson's (VG) alcoholic picrofuchsin staining on SHG in type I collagen (from tendon-rich C57BL/6). Multi-channel imaging and spectra analysis show that the strong SHG signal produced in fresh collagen type I fiber has been greatly suppressed after VG staining, which indicates that staining may induce the structural or characteristic changes of SHG-dependent crystal formed by collagen constituents, such as glycine, proline, and hydroxyproline.
非线性显微成像 多阶谐波产生 组织 180.4315 Nonlinear microscopy 190.4160 Multiharmonic generation 170.6930 Tissue The sensitivity of diffuse optical tomography (DOT) imaging exponentially decreases with the increase of photon penetration depth, which leads to a poor depth resolution for DOT. In this letter, an exponential adjustment method (EAM) based on maximum singular value of layered sensitivity is proposed. Optimal depth resolution can be achieved by compensating the reduced sensitivity in the deep medium. Simulations are performed using a semi-infinite model and the simulation results show that the EAM method can substantially improve the depth resolution of deeply embedded objects in the medium. Consequently, the image quality and the reconstruction accuracy for these objects have been largely improved.
层析成像 图像重建方法 生物医学成像 170.6960 Tomography 170.3010 Image reconstruction techniques 170.3880 Medical and biological imaging Experimental validation for time-domain fluorescence diffuse optical tomography of linear schemeDownload:646次
We present a full three-dimensional, featured-data algorithm for time-domain fluorescence diffuse optical tomography that inverts the Laplace-transformed time-domain coupled diffusion equations and employs a pair of appropriate transform-factors to effectively separate the fluorescent yield and lifetime parameters. By use of a time-correlation single-photon counting system and the normalized Born formulation, we experimentally validate that the proposed scheme can achieve simultaneous reconstruction of the fluorescent yield and lifetime distributions with a reasonable accuracy.
荧光扩散光层析 特征数据 时域 图像重建 时间相关单光子计数 170.3880 Medical and biological imaging 170.3660 Light propagation in tissues 170.6280 Spectroscopy, fluorescence and luminescence 170.6960 Tomography 170.3010 Image reconstruction techniques 170.6920 Time-resolved imaging Digital radiography (DR) and whole-body fluorescent optical imaging (WFOI) have been widely applied in the field of molecular imaging, with the advantages in tissues and functional imaging. The integration of them contributes to the development and discovery of medicine. We introduce an equipment, performance of which is better than that of another molecular imaging system manufactured by Kodak Corp. It can take real-time small animal imaging in vivo, with lower cost and shorter development cycle on the LabVIEW platform. At last, a paradigm experiment on a nude mouse with green fluorescent protein (GFP) transgenic tumor is given to present a real-time DR-WFOI fusion simultaneous image.
分子成像 透射成像 全域荧光成像 LabVIEW 110.0110 Imaging systems 130.0130 Integrated optics 120.0120 Instrumentation, measurement, and metrology Measurement of crater geometries after laser ablation of bone tissue with optical coherence tomographyDownload:506次
The feasibility of measuring crater geometries by use of optical coherence tomography (OCT) is examined. Bovine shank bone on a motorized translation stage with a motion velocity of 3 mm/s is ablated with a pulsed CO2 laser in vitro. The laser pulse repetition rate is 60 Hz and the spot size on the tissue surface is 0.5 mm. Crater geometries are evaluated immediately by both OCT and histology methods after laser irradiation. The results reveal that OCT is capable of measuring crater geometries rapidly and noninvasively as compared to histology. There are good correlation and agreement between crater depth estimates obtained by two techniques, whereas there exists distinct difference between crater width estimates when the carbonization at the sides of craters is not removed.
组织消融 光学相干层析成像技术 CO2激光 170.1020 Ablation of tissue 170.4500 Optical coherence tomography 140.3470 Lasers, carbon dioxide Fiber-optic Fourier-domain common-path OCTDownload:613次
We experimentally and theoretically investigated the performance of a fiber-optic based Fourier-domain common-path optical coherence tomography (OCT). The fiber-optic common-path OCT operated at the 840-nm center wavelength. The resolution of the system was 8.8 \mum (in air) and the working depth using a bare fiber probe was approximately 1.5 mm. The signal-to-noise ratio (SNR) of the system was analyzed. OCT images obtained by the system were also presented.
光学相干X射线层析 傅里叶光学和光信号处理 110.4500 Optical coherence tomography 070.0070 Fourier optics and signal processing A novel spectral calibration method is developed for spectral domain optical coherence tomography system. The method is based on two measurements of interference spectra from two reference mirror positions. It removes the influence of dispersion mismatch, and hence accurately determines the spectral distribution on the line-scan charge-coupled device (CCD) for sequent precise interpolation. High quality imaging can be realized with this method. Elimination of the degradation effect caused by dispersion mismatch is verified experimentally, and improved two-dimensional (2D) imaging of fresh orange pulp based on the proposed spectral calibration method is demonstrated.
谱域 光学相干层析成像 光谱校正 110.4500 Optical coherence tomography 120.2650 Fringe analysis 300.6190 Spectrometers In vitro birefringence imaging with spectral domain polarization-sensitive optical coherence tomographyDownload:619次
Spectral domain polarization-sensitive optical coherence tomography (SDPS-OCT) is a depth-resolved polarization-sensitive interferometry which integrates polarization optics into spectral domain optical coherence tomography (SD-OCT). This configuration can obtain birefringence information of samples and improve the imaging speed. In this paper, horizontally polarized light is used to replace natural light of the source. Then, right-rotated circularly polarized light is the incident sample light. To obtain two orthogonal components of the polarized interferogram, the reflected light of the reference arm is set to be 45O linearly polarized light. These two components are acquired by two spectrometers synchronously. The system was employed to achieve 12.8-\mum axial resolution and 4.36-\mum transverse resolution. We have imaged in vitro chicken tendon and muscle tissues with these system.
光学相干层析成像 双折射 偏振 170.4500 Optical coherence tomography 110.4500 Optical coherence tomography 260.1440 Birefringence 260.5430 Polarization The objective of this study is to demonstrate that tensile stress resulting due to applied force on cornea can be accurately measured by using a time-domain common-path optical coherence tomography (OCT) system with an external contact reference. The unique design of the common-path OCT is utilized to set up an imaging system in which a chicken eye is placed adjacent to a glass plate serving as the external reference plane for the imaging system. As the force is applied to the chicken eye, it presses against the reference glass plate. The modified OCT image obtained is used to calculate the size of contact area, which is then used to derive the tensile stress on the cornea. The drop in signal levels upon contact of reference glass plate with the tissue are extremely sharp because of the sharp decline in reference power levels itself, thus providing us with an accurate measurement of contact area. The experimental results were in good agreement with the numerical predictions. The results of this study might be useful in providing new insights and ideas to improve the precision and safety of currently used ophthalmic surgical techniques. This research outlines a method which could be used to provide high resolution OCT images and a precise feedback of the forces applied to the cornea simultaneously.
光学相干层析(OCT) 医学成像 生物成像 医用光学仪器 角膜 170.4500 Optical coherence tomography 170.3880 Medical and biological imaging 170.3890 Medical optics instrumentation The emergent light distribution of a new type of contact laser scalpel is measured in three different states using a light sensor. The relationship between the angle and the light intensity is analyzed. The results show that the strongest light is emitted from two sides and the front of the scalpel. The light from the front mainly plays a role of cutting. The light from two sides contributes to stanch the wound so as to remain a clear visual field during the surgery. It also helps to increase the cutting efficiency.
激光刀头 出射光分布 绿激光 激光手术 170.0170 Medical optics and biotechnology 170.1610 Clinical applications 140.3480 Lasers, diode-pumped A surface plasmon resonance (SPR) sensing system based on the optical cavity enhanced detection technique is experimentally demonstrated. A fiber-optic laser cavity is built with a SPR sensor inside. By measuring the laser output power when the cavity is biased near the threshold point, the sensitivity, defined as the dependence of the output optical intensity on the sample variations, can be increased by about one order of magnitude compared to that of the SPR sensor alone under the intensity interrogation scheme. This could facilitate ultra-high sensitivity SPR biosensing applications. Further system miniaturization is possible by using integrated optical components and waveguide SPR sensors.
表面等离子体共振 光谐振腔 光纤激光器 角度扫描 240.6680 Surface plasmons 250.5403 Plasmonics 060.3510 Lasers, fiber 280.1415 Biological sensing and sensors Different types of femtosecond optical tweezers have become a powerful tool in the modern biological field. However, how to control the irregular targets, including biological cells, using femtosecond optical tweezers remains to be explored. In this study, human red blood cells (hRBCs) are manipulated with femtosecond optical tweezers, and their states under different laser powers are investigated. The results indicate that optical potential traps only can capture the edge of hRBCs under the laser power from 1.4 to 2.8 mW, while it can make hRBCs turn over with the laser power more than 2.8 mW. It is suggested that femtosecond optical tweezers could not only manipulate biological cells, but also subtly control its states by adjusting the laser power.
飞秒激光 光镊 人红细胞 捕获 翻转 350.4855 Optical tweezers or optical manipulation 120.4820 Optical systems 170.4520 Optical confinement and manipulation A novel structure of fiber optic biosensor and its principle are introduced. The sample is detected in microchannels of several microns diameter in fiber optic biosensors. The relation between the optic fiber tapered angle and the fluorescence incident angle is calculated in signal receiving part. As the sensor is a zero-order system, calculating formula of the static sensitivity is derived. When ZnSe nano-crystalline cluster is used for marking the molecules, the static sensitivity for fiber optic biosensors is calculated. At the same time, the relation between the static sensitivity and the ratio of exciting wavelength to fluorescence wavelength is presented.
光纤生物传感器 静态灵敏度 半导体纳米晶体团簇 微通道 锥度角 160.2540 Fluorescent and luminescent materials 060.2370 Fiber optics sensors 280.1415 Biological sensing and sensors 350.3950 Micro-optics The ultra-compact biosensor based on the two-dimensional (2D) photonic crystal (PhC) microcavity is investigated. The performances of the sensor are analyzed theoretically using the Fabry-Perot (F-P) cavity model and simulated using the finite-difference time-domain (FDTD) method. The simulation results go along with the theoretical analysis.
折射率 传感器 光子晶体 微腔 130.3990 Micro-optical devices 130.6010 Sensors 140.3945 Microcavities 140.4780 Optical resonators To confirm the existence and properties of human meridians, the optical transport properties along the pericardium meridian and tissues around the pericardium meridian are studied noninvasively on twenty healthy volunteers in vivo and then compared with each other. Our study shows that the light propagating along the meridian and non-meridian directions both conform to the Beer's exponential attenuation law. However, statistical analysis of the results suggests that the optical transport properties of human meridian differ from those of the surrounding tissues over a low modulated frequency range (P<0.01), and light attenuation along the pericardium meridian is significantly less than that along the non-meridian direction. These findings not only indicate the existence of acupuncture meridian from the point of view of biomedical optics, but also shed new light on an approach to investigation of human meridians.
人体经脉 光传输特性 无损测量 170.0170 Medical optics and biotechnology 170.6930 Tissue 170.6935 Tissue characterization A spatial distribution of diffuse reflectance produced by obliquely incident light is not centered about the point of light entry. The value of shift in the center of diffuse reflectance is directly related to the absorption coefficient \mu_{a} and the effective attenuation coefficient \mu_{eff}. \mu_{a} and the reduced scattering coefficient \mu^{'}_{s} of human skin tissues in vivo are measured by oblique-incidence reflectometry based on the two-source diffuse theory model. For ten Chinese volunteers aged 15-63 years, \mu_{a} and \mu^{'}_{s} are noninvasively determined to be 0.029-0.075 and 0.52-0.97 mm^{-1}, respectively.
组织光学 漫反射 光学常数 皮肤组织 170.0170 Medical optics and biotechnology 170.6930 Tissue 120.5820 Scattering measurements 120.4530 Optical constants Reconstruction of absorption coefficient \mu_{a} and scattering coefficient \mu_{s} is very important for applications of diffuse optical tomography and near infrared spectroscopy. Aiming at the early cancer detection of cervix and stomach, we present a fast inverse Monte-Carlo scheme for extracting \mu_{a} and \mu_{s} of a tubular tissue from the measurement on frequency domain. Results show that the computation time for reconstructing one set of \mu_{a} and \mu_{s} is less than 1 min and the relative errors in reconstruction are less than +-10% for the optical properties of normal cervical tissue and precancerous lesions.
混浊介质 漫射 医学光学仪器 吸收 290.7050 Turbid media 290.1990 Diffusion 120.3890 Medical optics instrumentation 300.1030 Absorption Micro-Raman spectroscopy of single leukemic cellsDownload:505次
The Raman spectra from leukemic cell line (HL60) and normal human peripheral blood mononuclear cells (PBMCs) are obtained by confocal micro-Raman spectroscopy using near-infrared laser (785 nm) excitation. The scanning range is from 500 to 2000 cm^{-1}. The two average Raman spectra of normal PBMCs and carcinoma cells have clear differences because their structure and amount of nucleic acid, protein, and other major molecules are changed. The spectra are also compared and analyzed by principal component analysis (PCA) to demonstrate the two distinct clusters of normal and transformed cells. The sensitivity of this technique for identifying transformed cells is 100%.
300.6450 Spectroscopy, Raman 170.0170 Medical optics and biotechnology 170.1530 Cell analysis 170.1790 Confocal microscopy A feasible method for comparing the power dependent photostability of fluorescent proteinsDownload:630次
A feasible method of combining the concept of fluorescence half-life and the power dependent photobleaching rate for characterizing the practical photostability of fluorescent proteins (FPs) was introduced. Furthermore, by using a fluorescent photostability standard, a relative comparison of the photostabilty of FPs from different research groups was proposed, which would be of great benefit for developing novel FPs with optimized emission wavelength, better brightness, and improved photostability. We used rhodamine B as an example to verify this method and evaluate the practical photostability of a far-red FP, mKate-S158C. Experimental results indicated good potential of this method for further study.
荧光蛋白 光稳定性 荧光显微成像 160.2540 Fluorescent and luminescent materials 180.2520 Fluorescence microscopy 300.6390 Spectroscopy, molecular To investigate the effect of photodynamic therapy (PDT) with hematoporphrin monomethyl ether (HMME) on bovine immunodeficiency virus (BIV) can provide the basis theory for photoinactivation of human immunodeficiency virus (HIV). To assess the protection of HMME-PDT on the cell line Cf2Th infected with BIVR29 by 3-(4,5)-dimethylthiahiazol-2-y1-3,5-di-phenytetrazolium bromide (MTT) with power density of 5 and 25 mW/cm2 and energy density from 0.6 to 3 J/cm2. To observe the inhibition of membrane fusion using a new reporter cell line BIVE by fluorescence microscope. HMME-PDT has significant protectant effects on Cf2Th-BIVR29 with both power densities, especially in the group of high power density. Fluorescent microscope shows that there is no significant difference between the group of PDT and control, which means PDT could not inhibit the BIV-mediated membrane fusion.
光动力疗法 血卟啉单甲醚 牛免疫缺陷病毒 170.5180 Photodynamic therapy 170.1530 Cell analysis 170.2520 Fluorescence microscopy We investigated the effect of photodynamic therapy (PDT) with hematoporphyrin monomethyl ether (HMME) on the viability of Streptococcus mutans (S. mutans) cells on biofilms in vitro. Streptococcus mutans is the primary etiological agent of human dental caries. Since dental caries are localized infections, such plaque-related diseases would be well suited to PDT. The diode laser used in this study had the wavelength of 635 nm, whose output power was 10 mW and the energy density was 12.74 J/cm2. HMME was used as photosensitizer. Samples were prepared and divided into five groups: (1) HMME; (2) Laser; (3) HMME+Laser; (4) Control group (+) with chlorhexidine; and (5) Control group (-) with sterile physiological saline. Inoculum of S. mutans incubated with HMME also examined with fluorescence microscopy. PDT exhibited a significantly (P<0.05) increased antimicrobial potential compared with 20 \mum/mL HMME only, laser only, 0.05% chlorhexidine, and 0.9% sterile physiological saline, which reduced the S. mutans of the biofilm most effectively. Laser and 0.05% chlorhexidine were caused reduction in the viable counts of S. mutans significantly different (P<0.05) also, but these two test treatments did not statistically differ from each other. HMME group did not statistically differ with negative control group. Fluorescence microscopy indicated that HMME localized primarily in the S. mutans of the biofilm. It was demonstrated that HMME-mediated PDT was efficient at killing S. mutans of biofilms and a useful approach in the treatment of dental plaque-related diseases.
光动力疗法(Photodynamic therapy PDT) 变形链球菌 生物膜 龋病 170.5180 Photodynamic therapy 170.1530 Cell analysis 170.2520 Fluorescence microscopy In landmark-based image registration, estimating the landmark correspondence plays an important role. In this letter, a novel landmark correspondence estimation technique using mean shift algorithm is proposed. Image corner points are detected as landmarks and mean shift iterations are adopted to find the most probable corresponding point positions in two images. Mutual information between intensity of two local regions is computed to eliminate mis-matching points. Multi-level estimation (MLE) technique is proposed to improve the stability of corresponding estimation. Experiments show that the precision in location of correspondence landmarks is exact. The proposed technique is shown to be feasible and rapid in the experiments of various mono-modal medical images.
100.6950 Tomographic image processing 100.0100 Image processing 动态信息
动态信息 丨 2024-04-19
COL Highlight (Vol. 22, Iss. 2): 主编推荐 | 经典导波与拓扑单向波间的高效转换动态信息 丨 2024-04-19
COL Highlight (Vol. 22, Iss. 1): 主编推荐 | 单片集成硅基灵活栅格MWSS为突破“容量危机”提供新策略动态信息 丨 2024-04-10
COL 封面故事 (Vol. 22, Iss. 2): 封面 |构造任意自相似类贝塞尔光束构造新方法动态信息 丨 2024-03-29
COL Highlight (Vol. 22, Iss. 2): 主编推荐 |声光调制的干涉增强效应,助力光学量子信息技术动态信息 丨 2024-03-25
COL 封面故事 (Vol. 22, Iss. 1): 基于时空耦合效应的超宽带频率转换技术激光评论微信公众号
点击菜单“联系编辑”即可添加期刊编辑为好友啦