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1.
The use of the depth discriminination property of the confocal scanning microscope for surface profiling has been adapted to provide a method of high-resolution three-dimensional surface profilometry. Measurements on a semiconductor specimen demonstrate the technique; depth variations of the order of 0.1 m are clearly resolved. 相似文献
2.
We have developed a miniature scanning confocal microscope that uses electrostatically actuated microlenses for focusing and scanning. Objective lenses, scanners, a pupil, and a pinhole of the confocal microscope are microfabricated and integrated into a volume smaller than 2 mm3 by stacking these components. Objective lenses are composed of two vertically cascaded polymer microlenses integrated into micromachined comb actuators. Raster scanning is implemented by electrostatically actuating each microlens in orthogonal directions. We have demonstrated reflection confocal imaging with 3-microm transverse resolution over a 100-microm field of view and a 0.38-mm working distance at lambda = 633 nm. 相似文献
3.
A confocal reflectance microscope has been developed that incorporates a dual-wedge scanner to reduce the size of the device relative to current raster scanning instruments. The scanner is implemented with two prisms that are rotated about the optical axis. Spiral and rosette scans are performed by rotating the prisms in the same or opposite directions, respectively. Experimental measurements show an on-axis lateral resolution of 1.6 microm and optical sectioning of 4.7 microm, which compares with a diffraction-limited resolution of 0.8 and 1.9 microm, respectively. 相似文献
4.
Measurements of water as the most available and vitally important element were performed using the laser confocal scanning microscope with the purpose of extending the range of its application. In this work, the measured Raman spectra of water obtained for different water samples—unprocessed, purified, and mineral, in different phase states, and after filtration and processing using different methods—are presented. 相似文献
5.
With the help of adaptive optics(AO) technology, cellular level imaging of living human retina can be achieved.Aiming to reduce distressing feelings and to avoid potential drug induced diseases, we attempted to image retina with dilated pupil and froze accommodation without drugs. An optimized liquid crystal adaptive optics camera was adopted for retinal imaging. A novel eye stared system was used for stimulating accommodation and fixating imaging area. Illumination sources and imaging camera kept linkage for focusing and imaging different layers. Four subjects with diverse degree of myopia were imaged. Based on the optical properties of the human eye, the eye stared system reduced the defocus to less than the typical ocular depth of focus. In this way, the illumination light can be projected on certain retina layer precisely.Since that the defocus had been compensated by the eye stared system, the adopted 512 × 512 liquid crystal spatial light modulator(LC-SLM) corrector provided the crucial spatial fidelity to fully compensate high-order aberrations. The Strehl ratio of a subject with-8 diopter myopia was improved to 0.78, which was nearly close to diffraction-limited imaging. By finely adjusting the axial displacement of illumination sources and imaging camera, cone photoreceptors, blood vessels and nerve fiber layer were clearly imaged successfully. 相似文献
6.
We describe a simple implementation of a slit scanning confocal microscope to obtain an axial resolution better than that of a point-scanning confocal microscope. Under slit illumination, images of a fluorescent object are captured using an array detector instead of a line detector so that out-of-focus light is recorded and then subtracted from the adjacent images. Axial resolution after background subtraction is 2.2 times better than the slit confocal resolution, and out-of-focus image suppression is calculated to attenuate with defocus faster by 1 order of magnitude than in the point confocal case. 相似文献
7.
We have developed an adaptive optics (AO) fundus camera to obtain high resolution retinal images of eyes. We use a liquid
crystal phase modulator to compensate the aberrations of the eye for better resolution and better contrast in the images.
The liquid crystal phase modulator has a wider dynamic range to compensate aberrations than most mechanical deformable mirrors
and its linear phase generation makes it easy to follow eye movements. The wavefront aberration was measured in real time
with a sampling rate of 10 Hz and the closed loop system was operated at around 2 Hz. We developed software tools to align
consecutively obtained images. From our experiments with three eyes, the aberrations of normal eyes were reduced to less than
0.1 μm (RMS) in less than three seconds by the liquid crystal phase modulator. We confirmed that this method was adequate
for measuring eyes with large aberrations including keratoconic eyes. Finally, using the liquid crystal phase modulator, high
resolution images of retinas could be obtained. 相似文献
8.
活体人眼共焦扫描成像系统的分辨率受到人眼像差、数值孔径和探测针孔尺度的限制,本文设计了一套超分辨活体人眼视网膜共焦扫描系统,采用自适应光学技术探测并校正人眼像差,结合光学超分辨技术提高系统分辨率,补偿有限尺度针孔对分辨率的影响,并获得活体人眼的实时、高分辨图像.
关键词:
超分辨
共焦扫描光学显微术
眼科光学
自适应光学 相似文献
9.
讨论了共焦扫描光学显微镜的高分辨率性质,指出共焦扫描显微镜由于采用点探测器,因而视场大大减小,信噪比大大提高,同时每幅图像逐点扫描形成,在光学系统信息能力不变的前提下,系统的空间域通带宽度增加和时域通带宽度减小。因而可成高分辨率的像,特别是其独特的深度分辨率特性使得可以实现光学断层扫描成像。给出了所研制的共焦扫描荧光显微镜所获得光学断层扫描图像 相似文献
10.
We have systematically analyzed the spatial dynamics of the polarization state of light in smoothly inhomogeneous anisotropic media. As a medium of this kind, we have considered a nematic liquid crystal with twist orientation. A system of coupled equations has been solved with respect to the Cartesian components of the electric-field component using a rotating coordinate system. We have shown that, upon propagation of light in this medium, the state of the polarization experiences oscillations the spatial frequency of which depends on the thickness of the specimen. Our analysis also has shown that, at an appropriate choice of the thickness, this twist cell behaves as a broadband half-wave plate. 相似文献
11.
本文主要包括两方面的内容,一方面描述用液晶光阀产生空间与时间性能可控的小尺寸薄相位屏;另一方面则讨论用液晶空间光调制器实现波前相位畸变校正的可能性。从而表明,这类价格低廉、结构简单而性能可靠的非线性光学器件可望在高性能新型自适应光学系统中得到广泛应用。 相似文献
12.
激光扫描共焦显微术和多光子显微术等新的显微成像技术可以对厚的生物样品实现光学断层成像 ,因而在生物医学诊断领域具有重要的应用前境。在Fried的一维分辨度理论的基础上 ,系统地讨论了运用共焦扫描荧光显微术在进行光学断层成像时 ,其光学断层平面分辨度与信噪比之间的定量关系 ,建立了实际显微成像系统平面测量精度的定量计算方法。所得出的结果对于选择共焦扫描显微成像系统的最佳参数及评价所设计的显微成像系统的性能具有重要的意义。 相似文献
13.
A novel approach that simplifies the laser source requirements for confocal and multiphoton laser scanning (CLSM and MPLSM)
using the novel dispersion properties of photonic crystal fibre (PCF) is reported. By tuning the fs-pulsed Ti:Sapphire laser
to the zero dispersion wavelength of the PCF, the spectral and temporal properties of the source are largely unaffected and
hence this source can easily be used for MPLSM. Conversely, by tuning the Ti:Sapphire laser emission wavelength by less than
10 nm to anomalously pump the PCF, the resultant white-light supercontinuum source can perform CLSM. Sequential CLSM and MPLSM
of a double-labelled guinea pig detrusor (smooth muscle layer) specimen is described.
PACS 87.64.Tt; 87.64.Vv; 42.65.Ky 相似文献
14.
A confocal Raman microscope (CRM) facilitates visualization of the spatial distribution of molecular bonds or phonon modes at the submicron level and has been extensively used in the characterization of nanomaterials and devices. The lateral and axial resolution is a key specification that defines the performance of CRM, however, the interpretation of spatial resolution in the literature is often ambiguous, making it often difficult to directly compare Raman images obtained under different conditions. In this report, a convenient and reliable measurement protocol using dispersed carbon nanotubes and suspended graphene as test specimens is proposed to facilitate the determination of the lateral and axial resolutions of a CRM. Spatial resolution values comparable to the results based on Rayleigh criterion calculations were obtained using Raman mapping images of test specimens. This was achieved without the need for complex deconvolution processes or the consideration of an asymmetric dielectric environment. 相似文献
15.
Optical aberrations due to the inhomogeneous refractive index of tissue degrade the resolution and brightness of images in deep-tissue imaging. We introduce a confocal fluorescence microscope with adaptive optics, which can correct aberrations based on direct wavefront measurements using a Shack-Hartmann wavefront sensor with a fluorescent bead used as a point source reference beacon. The results show a 4.3× improvement in the Strehl ratio and a 240% improvement in the signal intensity for fixed mouse tissues at depths of up to 100 μm. 相似文献
16.
A scanning optical microscope is used to measure directly the refractive-index profile of an optical fibre. The effects of illuminating the fibre end with a highly convergent beam of light are considered. 相似文献
17.
A new confocal scanning laser microscope/macroscope (cslm/M) has recently been developed. It combines in one instrument the high resolution capability of a confocal scanning beam microscope for imaging small specimens, with good resolution confocal imaging of macroscopic specimens. Some of its main features include: (a) 0.25 μm lateral resolution in the microscope mode and 5 μm lateral resolution in the macroscope mode; (b) a field of view that can vary from 25 μm × 25 μm to 75,000 μm × 75,000 μm; (c) capability for acquiring large data sets from 512 × 512 pixels to 2048 × 2048 pixels; (d) 0.5 μm depth resolution in the microscope mode and 200 μm depth resolution in the macroscope mode. In this work the cslm/M was used to image whole biological specimens (> 5 m diameter), including insects which are ideal specimens for the macroscope. Specimens require no preparation, unlike scanning electron microscope (SEM) specimens which require a conductive coating. The specimens described in this paper are too large to be imaged in their entirety by a scanning beam laser microscope, however they can be imaged by slower scanning stage microscopes. In the macroscope mode the cslm/M was used to acquire a large number (e.g. 20–40) of confocal image slices which were then used to reconstruct a three-dimensional image of the specimen. High resolution images were collected by the cslm/M by switching to the microscope mode where high numerical aperture (NA) objectives were used to image a small area of interest. Reflected-light and fluorescence images of plant and insect specimens are presented which demonstrate the morphological details obtained in various imaging modes. A process for three-dimensional visualization of the data is described and images are shown. 相似文献
18.
A cubic single crystal of GaAs with two polished (100)-surfaces was examined with a scanning acoustic microscope (SAM) in transmission mode. The images of the transmitted ultrasound amplitude measured at frequencies of 350–400 MHz contain sufficient information about the acoustic anisotropy of the crystal to determine the complete set of the three elastic constants C 11, C 12, C 44 numerically. This was done by an interactive fitting procedure correlating simulated images with the measured one. This technique seems to be universally applicable to virtually all sorts of single crystals. Compared to plane wave investigations it saves preparatory labour since one single crystal orientation suffices for a determination of all elastic constants. 相似文献
19.
Although confocal fluorescence microscopes are widely used in biology and have been proven to be promising diagnostic tools in dermatologic diagnostics, they are at present uncommon in medical practice. This is mainly due to high costs of acquisition and their large and complex outline. With the integration of a MEMS scanner we present a demonstration system of a confocal fluorescence laser scanning microscope which is affordable and portable. It has a field of view of 500 μm × 500 μm and is mainly composed of off-the-shelf components. 相似文献
20.
The paper reviews and discusses the latest developments in the field of the photonic liquid crystal fibers that have occurred
for the last three years in view of new challenges for both fiber optics and liquid crystal photonics. In particular, we present
the latest experimental results on electrically induced birefringence in photonic liquid crystal fibers and discuss possibilities
and directions of future developments. 相似文献
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