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Increasing the aperture of the parabolic trough concentrator (PTC) can effectively reduce costs and help promote. This paper proposed a circle and semicircle absorber tubes (AT) with a flat reflector (FR) in it for the large-aperture PTC system and the size of the AT was determined for the PTC with 8 m aperture width and 80° half rim-angle. The result shown the PTC system using a semi-circular AT with a diameter of 100 mm has the highest average thermal efficiency of 71.6% with DNI 400–1000 W/m2 at about 500 °Cand has best uniformity of 38.8%. However, its deformation is highest and 1.7 and 1.6 times other two ATs. Therefore, how to reduce the deflection has become a research direction in the future. Currently, the circular AT with a diameter of 80 mm is the most practical with an average thermal efficiency of 69.1% and a minimum deflection.

The Infrared Microspectroscopy Beamline at the Australian Synchrotron is equipped with a Fourier transform infrared (FTIR) spectrometer, which is coupled with an infrared (IR) microscope and a choice of two detectors: a single-point narrow-band mercury cadmium telluride (MCT) detector and a 64 × 64 multi-pixel focal plane array (FPA) imaging detector. A scanning-based point-by-point mapping method is commonly used with a tightly focused synchrotron IR beam at the sample plane, using an MCT detector and a matching 36× IR reflecting objective and condenser (NA = 0.5), which is time consuming. In this study, the beam size at the sample plane was increased using a 15× objective and the spatio-spectral aberrations were investigated. A correlation-based semi-synthetic computational optical approach was applied to assess the possibilities of exploiting the aberrations to perform rapid imaging rather than a mapping approach.

This chapter elucidates the general introduction of light, perception of colour, mechanism of image formation in the eye, basic principles of light microscope and components of light microscope along with guidelines of handling of the microscope. The spherical lens of the microscope may have several optical faults or aberrations. Image distortion occurs due to these various optical aberrations. The common aberrations include chromatic aberration, spherical aberration, astigmatism and curvature of field. This chapter highlights the causes of these aberrations and their solutions. In addition various other microscopes have also been discussed in this chapter.

A limitation of standard brightfield microscopy is its low contrast images, especially for thin specimens of weak absorption, and biological species with refractive indices very close in value to that of their surroundings. We demonstrate, using a planar photonic chip with tailored angular transmission as the sample substrate, a standard brightfield microscopy can provide both darkfield and total internal reflection (TIR) microscopy images with one experimental configuration. The image contrast is enhanced without altering the specimens and the microscope configurations. This planar chip consists of several multilayer sections with designed photonic band gaps and a central region with dielectric nanoparticles, which does not require top-down nanofabrication and can be fabricated in a larger scale. The photonic chip eliminates the need for a bulky condenser or special objective to realize darkfield or TIR illumination. Thus, it can work as a miniaturized high-contrast-imaging device for the developments of versatile and compact microscopes., The authors design a planar photonic chip with several multilayers of photonic band gaps and a region of dielectric nanoparticles for tailored angular transmission. They use it as sample substrate for high-contrast darkfield and total internal reflection microscopy on a conventional microscope.

A hyper-aspheroid is a surface of revolution (with a specified vertex curvature) that nears or extends beyond where it’s parallel to the axis. The familiar ‘hyperhemispherical’ is one limiting example, but the superconic and rational Bezier approaches are more flexible. Both will be applied to the redesign of a condenser system from the late Juan Rayces’ Eikonal program but using the author’s own design code.

Pseudo-random paths are a useful tool to reduce mid-spatial frequency errors created in the processing of optical surfaces by sub-aperture polishing tools. Several types of patterns have been proposed, including hexagonal, square and circular, but prior literature has largely focused on flat and gently curved surfaces. Here, an extension of the circular-random path to strongly curved aspheric and freeform surfaces is proposed. The main feature of the algorithm is to cover the entire surface to be polished with a uniformly distributed tool path. Aspheric condenser lenses are then polished with a regular raster and circular-random path. Analysis of the optical performance shows that the random path can reduce the amplitude of mid-spatial frequency errors and relative intensity of satellite images. These features are particularly desirable in short wavelength applications, such as mirrors for EUV and X-ray.

We have developed an X-ray zoom condenser optical system using deformable mirrors that can adjust the beam size by deformation of their shape. The shapes of deformable mirrors are changed by a combination of mechanical and piezoelectric bending. Large deformations up to third order polynomials are achieved by mechanical bending. More precise shapes are achieved by piezoelectric bimorph mirror. However, because both ends of the mirror are mechanically clamped, capability of deformation by piezoelectric bending is lower than that of free-standing piezoelectric bimorph mirrors. So, we propose a bending method that tunes the mechanical bending conditions to intentionally leave the optimized shape error to be easily compensated by the piezoelectric bending process.

We propose the scanning electron microscope (SEM) using the graphene-oxide-semiconductor type planar electron emission device as an electron source. Graphene/Oxide/Semiconductor (GOS) structure realizes very high electron emission efficiency of over 30 % and it can be operated in low vacuum condition and low applied voltage. Therefore, SEM using the GOS electron source can eliminate several condenser lenses from the electron optics which are needed in the conventional SEM due to the very small divergence angle of the electron beams emitted from the flat surface. In this study, we installed the GOS type electron source into the conventional SEM and successfully obtained the stable SEM image with a probe current of 20 pA without noise using GOS electron source. In addition, we found the optimal electron optics for the parallel electron beams with a very small divergence angle of approximately 0 degree by the simulation of the electron beam trajectory.

Purpose The purpose of this paper is to propose an alternative approach to improve the performance of microelectromechanical systems (MEMSs) silicon (Si) condenser microphones in terms of operating frequency and sensitivity through the introduction of a secondary material with a contrast of mechanical properties in the corrugated membrane. Design/methodology/approach Finite element method from COMSOL is used to analyze the MEMS microphones performance consisting of solid mechanic, electrostatic and thermoviscous acoustic interfaces. Hence, the simulated results could described the physical mechanism of the MEMS microphones, especially in the case of microphones with complex geometry. A 2-D model was used to simplify computation by applying axis symmetry condition. Findings The simulation results have suggested that the operating frequency range of the microphone could be extended to be operated beyond 20 kHz in the audible frequency range. The data showed that the frequency resonance of the microphone using a corrugated Si membrane with SiC as the embedded membrane is increased up to 70 kHz compared with 63 kHz for the plane Si membrane, whereas the microphone’s sensitivity is slightly decreased to −79 from −76 dB. Furthermore, the frequency resonance of a corrugated membrane microphone could be improved from 26 to 70 kHz by embedding the SiC material. Last, the sensitivity and frequency resonance value of the microphones could be modified by adjusting the height of the embedded material. Originality/value Based on these theoretical results, the proposed modification highlighted the advantages of simultaneous modifications of frequency and sensitivity that could extend the applications of sound and acoustic detections in the ultrasonic spectrum with an acceptable performance compared with the typical state-of-the-art Si condenser microphones.

WOS: 000485855500003 Problems such as low contrast, noise, and edge blur are often encountered in color infrared images produced by infrared cameras. To solve these problems, we propose a new image enhancement algorithm based on the gravitational force and lateral inhibition network. First, information on total gravitational force for each dimension of the color infrared image was obtained. These two-dimensional three gray level images obtained using three-dimensional color properties help to define noise, edge and region within each dimension. Secondly, these three gray level images were subjected to a dual threshold value. A mean filter was used to reduce noise, while the lateral inhibition network was used for resolution and edge detection, and the regional gravity factor was used for contrast control. Finally, each dimension was combined again and a color enhanced image was produced. This study sets out to develop a method of enhancement images for infrared image analysis in cooling systems. The images used in the study are made up of a compressor, a condenser, and an evaporator belonging to the cooling system. The implementation of our method is simple and easy to understand and yields more accurate results. The experimental results show that the proposed method can eliminate noise, blur, and low contrast, and can also improve the details of infrared images better than other methods.

An equation for the relation between the X-ray source size and focal spot size of a single-bounce ellipsoidal glass monocapillary X-ray condenser (SBEGMXC) was constructed. According to this equation, a method by measuring the focal spot size of an SBEGMXC was used to determine the average slope error of the SBEGMXC, and this method based on an X-ray source with an adjustable source size. Compared with the existing methods for measuring the slope error of an SBEGMXC, this method could be used to obtain the average of slope errors originating from every point on the inner surface of the SBEGMXC.

Photoacoustic imaging is becoming a very promising tool for the research of living organisms. It combines the high contrast of optical imaging and the high resolution of acoustic imaging to realize the imaging of absorption clusters in biological tissues. Since the scattering of ultrasound signals in biological tissues is 2-3 orders of magnitude weaker than the scattering of light in biological tissues, the endogenous absorption difference of tissues is directly used in the imaging process, so photoacoustic imaging has the advantages of deep imaging depth and non-destructive. As an important branch of photoacoustic imaging, photoacoustic microscopy can provide micron-level or even sub-micron-level imaging resolution, which is of great significance for biological research such as blood vessel detection. Since the lateral resolution of the photoacoustic microscopy imaging system depends on the focus of the laser, a higher resolution can be obtained by increasing the numerical aperture of the condenser objective. However, a large numerical aperture usually means a shorter working distance and makes the entire imaging system very sensitive to small optical defects. Therefore, the improvement of resolution through this method will be limited in practical applications. This paper implements a method of using iterative deconvolution to obtain a high-resolution photoacoustic image of the brain. The focal spot of the photoacoustic microscopy is measured to obtain the lateral PSF (point spread function) of the system. Making the measured PSF as the initial system PSF to perform Lucy- Richardson (LR) deconvolution. The image resolution of cerebral vasculature obtained by this method is higher. The full width at half maximum (FWHM) of width of the same cerebral capillaries before and after deconvolution are 7 μm and 3.6 μm, respectively, and the image definition is increased by about 1.9 times. Experiments show that this method can further improve the clarity of photoacoustic images of cerebral capillaries, which lays the foundation for further research on brain imaging.

Photoacoustic imaging is becoming a very promising tool for the research of living organisms. It combines the high contrast of optical imaging and the high resolution of acoustic imaging to realize the imaging of absorption clusters in biological tissues. Since the scattering of ultrasound signals in biological tissues is 2-3 orders of magnitude weaker than the scattering of light in biological tissues, the endogenous absorption difference of tissues is directly used in the imaging process, so photoacoustic imaging has the advantages of deep imaging depth and non-destructive. As an important branch of photoacoustic imaging, photoacoustic microscopy can provide micron-level or even sub-micron-level imaging resolution, which is of great significance for biological research such as blood vessel detection. Since the lateral resolution of the photoacoustic microscopy imaging system depends on the focus of the laser, a higher resolution can be obtained by increasing the numerical aperture of the condenser objective. However, a large numerical aperture usually means a shorter working distance and makes the entire imaging system very sensitive to small optical defects. Therefore, the improvement of resolution through this method will be limited in practical applications. This paper implements a method of using iterative deconvolution to obtain a high-resolution photoacoustic image of the brain. The focal spot of the photoacoustic microscopy is measured to obtain the lateral PSF (point spread function) of the system. Making the measured PSF as the initial system PSF to perform Lucy- Richardson (LR) deconvolution. The image resolution of cerebral vasculature obtained by this method is higher. The full width at half maximum (FWHM) of width of the same cerebral capillaries before and after deconvolution are 7 μm and 3.6 μm, respectively, and the image definition is increased by about 1.9 times. Experiments show that this method can further improve the clarity of photoacoustic images of cerebral capillaries, which lays the foundation for further research on brain imaging.

Coccoliths are major contributors to the particulate inorganic carbon in the ocean that is a key part of the carbon cycle. The coccoliths are a few micrometres in length and weigh a few picogrammes. Their birefringence characteristics in polarized optical microscopy have been used to estimate their mass. This method is rapid and precise because camera sensors produce excellent measurements of light. However, the current method is limited because it requires a precise and replicable set-up and calibration of the light in the optical equipment. More precisely, the light intensity, the diaphragm opening, the position of the condenser and the exposure time of the camera have to be strictly identical during the calibration and the analysis of calcite crystal. Here we present a new method that is universal in the sense that the thickness estimations are independent from a calibration but result from a simple equation. It can be used with different cameras and microscope brands. Moreover, the light intensity used in the microscope does not have to be strictly and precisely controlled. This method permits the measurement of crystal thickness up to 1.7 µm. It is based on the use of one left circular polarizer and one right circular polarizer with a monochromatic light source using the following equation: d=λπΔnarctanILRILL, where d is the thickness, λ the wavelength of the light used, Δn the birefringence, and ILR and ILL the light intensity measured with a right and a left circular polarizer. Because of the alternative and rotational motion of the quarter-wave plate of the circular polarizer, we coined the name of this method “bidirectional circular polarization” (BCP).

Electron 3D crystallography can reveal the atomic structure from undersized crystals of various samples owing to the strong scattering power of electrons. Here, a direct electron detector DE64 was tested for small and thin crystals of protein and an organic molecule using a JEOL CRYO ARM 300 electron microscope. The microscope is equipped with a cold-field emission gun operated at an accelerating voltage of 300 kV, quad condenser lenses for parallel illumination, an in-column energy filter, and a stable rotational goniometer stage. Rotational diffraction data were collected in an unsupervised manner from crystals of a heme-binding enzyme catalase and a representative organic semiconductor material Ph-BTBT-C10. The structures were determined by molecular replacement for catalase and by the direct method for Ph-BTBT-C10. The analyses demonstrate that the system works well for electron 3D crystallography of these molecules with less damaging, a smaller point spread, and less noise than using the conventional scintillator-coupled camera.

Photoacoustic imaging is becoming a very promising tool for the research of living organisms. It combines the high contrast of optical imaging and the high resolution of acoustic imaging to realize the imaging of absorption clusters in biological tissues. Since the scattering of ultrasound signals in biological tissues is 2-3 orders of magnitude weaker than the scattering of light in biological tissues, the endogenous absorption difference of tissues is directly used in the imaging process, so photoacoustic imaging has the advantages of deep imaging depth and non-destructive. As an important branch of photoacoustic imaging, photoacoustic microscopy can provide micron-level or even sub-micron-level imaging resolution, which is of great significance for biological research such as blood vessel detection. Since the lateral resolution of the photoacoustic microscopy imaging system depends on the focus of the laser, a higher resolution can be obtained by increasing the numerical aperture of the condenser objective. However, a large numerical aperture usually means a shorter working distance and makes the entire imaging system very sensitive to small optical defects. Therefore, the improvement of resolution through this method will be limited in practical applications. This paper implements a method of using iterative deconvolution to obtain a high-resolution photoacoustic image of the brain. The focal spot of the photoacoustic microscopy is measured to obtain the lateral PSF (point spread function) of the system. Making the measured PSF as the initial system PSF to perform Lucy- Richardson (LR) deconvolution. The image resolution of cerebral vasculature obtained by this method is higher. The full width at half maximum (FWHM) of width of the same cerebral capillaries before and after deconvolution are 7 μm and 3.6 μm, respectively, and the image definition is increased by about 1.9 times. Experiments show that this method can further improve the clarity of photoacoustic images of cerebral capillaries, which lays the foundation for further research on brain imaging.

We propose label-free and motion-free resolution-enhanced intensity diffraction tomography recovering the 3D complex refractive index distribution of an object. By combining an annular illumination strategy with a high numerical aperture (NA) condenser, we achieve near diffraction-limited lateral resolution of 346 nm and axial resolution of 1.2 µm over 130 130 8 µm3 volume. Our annular pattern matches the system’s maximum NA to reduce the data requirement to 48 intensity frames. The small data requirement and high resolution enable fast 3D quantitative refractive index imaging of biological cells across hundreds of nanometers scales. The reIDT system is directly built on a standard commercial microscope with a simple LED array source and condenser lens adds-on, and promises broad applications for natural biological imaging with minimal hardware modifications. To test the capabilities of our technique, we present the 3D complex refractive index reconstructions on the Henrietta Lacks (HeLa) and HT29 human cancer cells. Our work provides an important step in intensity-based diffraction tomography towards high resolution imaging applications.

We propose label-free and motion-free resolution-enhanced intensity diffraction tomography (reIDT) recovering the 3D complex refractive index distribution of an object. By combining an annular illumination strategy with a high numerical aperture (NA) condenser, we achieve near diffraction-limited lateral resolution of 346 nm and axial resolution of 1.2 μm over 130 × 130 × 8 μm3 volume. Our annular pattern matches the system’s maximum NA to reduce the data requirement to 48 intensity frames. The reIDT system is directly built on a standard commercial microscope with a simple LED array source and condenser lens adds-on, and promises broad applications for natural biological imaging with minimal hardware modifications. To test the capabilities of our technique, we present the 3D complex refractive index reconstructions on an absorptive USAF resolution target. Our work provides an important step in intensity-based diffraction tomography towards high resolution imaging applications.

We present a design of a compact transmission water-window microscope based on the Z-pinching capillary discharge nitrogen plasma source. The microscope operates at wavelength of 2.88 nm (430 eV), and with its table-top dimensions provides an alternative to large-scale soft X-ray (SXR) microscope systems based on synchrotrons and free-electron lasers. The emitted soft X-ray radiation is filtered by a titanium foil and focused by an ellipsoidal condenser mirror into the sample plane. A Fresnel zone plate was used to create a transmission image of the sample onto a charge-coupled device (CCD) camera. To assess the resolution of the microscope, we imaged a standard sample-copper mesh. The spatial resolution of the microscope is 75 nm at half-pitch, calculated via a 10&ndash, 90% intensity knife-edge test. The applicability of the microscope is demonstrated by the imaging of green algae-Desmodesmus communis. This paper describes the principle of capillary discharge source, design of the microscope, and experimental imaging results of Cu mesh and biological sample.

Various types of X-ray focusing optical systems are used at X-ray synchrotron radiation and free-electron laser facilities. However, these are designed for specific purposes and fixed optical parameters such as the numerical aperture (NA). Their lack of adaptability limits their application targets. In this research, we developed an X-ray adaptive focusing optical system which can control the beam size without moving the position of focus. The optical system consists of two deformable mirrors in one dimension. To vary the focused beam size, the NA is controlled by deforming the shape of the mirrors from concave to convex. The results will be presented along with the aberration properties estimated by ray trace and wave optical methods.

Optoacoustic (OA) imaging has the capacity to effectively bridge the gap between macroscopic and microscopic realms in biological imaging. High-resolution OA microscopy has so far been performed via point-by-point scanning with a focused laser beam, thus greatly restricting the achievable imaging speed and/or field of view. Herein we introduce multifocal structured illumination OA microscopy (MSIOAM) that attains real-time 3D imaging speeds. For this purpose, the excitation laser beam is shaped to a grid of focused spots at the tissue surface by means of a beamsplitting diffraction grating and a condenser and is then scanned with an acousto-optic deflector operating at kHz rates. In both phantom and in vivo mouse experiments, a 10 mm wide volumetric field of view was imaged with 15 Hz frame rate at 28 μm spatial resolution. The proposed method is expected to greatly aid in biological investigations of dynamic functional, kinetic, and metabolic processes across multiple scales., Light: Science & Applications, 9 (1), ISSN:2047-7538

We present and compare the designs of three types of neutron microscopes for high-resolution neutron imaging. Like optical microscopes, and unlike standard neutron imaging instruments, these microscopes have both condenser and image-forming objective optics. The optics are glancing-incidence axisymmetric mirrors and therefore suitable for polychromatic neutron beams. The mirrors are designed to provide a magnification of 10 to achieve a spatial resolution of better than 10 &mu, m. The resolution of the microscopes is determined by the mirrors rather than by the L/Dratio as in conventional pinhole imaging, leading to possible dramatic improvements in the signal rate. We predict the increase in the signal rate by at least two orders of magnitude for very high-resolution imaging, which is always flux limited. Furthermore, in contrast to pinhole imaging, in the microscope, the samples are placed far from the detector to allow for a bulky sample environment without sacrificing spatial resolution.

Transmitted light imaging is an important tool in biophysics for applications that include sample analysis, recording samples whose viability is compromised by high levels of illumination (e.g., live cell tracking), and finding regions of interest in a sample. Koehler transillumination is a powerful illumination method used in commercial microscopes; yet commercial Koehler condensers are expensive, are difficult to integrate into tabletop systems, and make learning the concepts of Koehler illumination difficult because of their closed-box nature. Here, we show a protocol to build a simple 4f Koehler illumination system that offers advantages with respect to commercial condensers in terms of simplicity, cost, and compatibility with tabletop systems, such as open-source light sheet fluorescence microscopes. We include step-by-step instructions that can be followed by advanced undergraduate or graduate students without experience in optics on how to align and assemble the illuminator, along with a list of the necessary parts for assembly. We also include supplemental material that describes 4 supporting educational activities students can conduct with the apparatus and helps in the understanding of key concepts relevant to Koehler illumination and optics. The performance of the system is comparable to that of commercial condensers and significantly better, in terms of illumination homogeneity and depth of field (optical sections are possible), than that of LED flashlights, such as those found in low-cost diagnostic devices and tabletop systems.

We give two precise estimates for the Green energy of a discrete charge, concentrated in the points on the circles, with respect to the concentric rotation domain in the d-dimensional Euclidean space, d>2.The proof is based on the application of a dissymmetrization, extremal metrics approach and an asymptotic formula for the condenser capacities in the case when some of its plates contract to given points., 8 pages

The interpretation of cell biological processes hinges on the elucidation of the underlying structures. Their three-dimensional analysis using electron tomography has extended our understanding of cellular organelles tremendously. The investigations depend on the availability of appropriate instruments for data recording. So far, such investigations have been done to a great extent on 300 keV transmission electron microscopes. Here we show the implementation of STEM tomography on a 200 kV FEG transmission electron microscope, including the tuning of the condenser for forming a beam with a small illumination aperture, dual-axis data recording, and evaluation of the maximum sample thickness and quality of the data. Our results show that the approach is accomplishable and promising, with high reliability, and reaching excellent data quality from plastic sections with a thickness of at least 900 nm.

Microscopes with an adjustable condenser can be aligned or set-up for Kohler illumination. Detailed instructions, as well as a short guide, facilitate the correct alignment of the microscope in order to maintain a uniformly illuminated high power field.

This chapter gives an introduction to basic optical principles and components of a light microscope (light source, condenser, objective [finite and infinite systems], tube lens, and eyepiece). Light microscope imaging of complex structured, three-dimensional objects having a high thickness and low contrast due to a lack of intrinsic color, presents a number of challenges for conventional types of illumination. Several technical modifications and additional alternative techniques have been presented and evaluated in the following sections.

Fourier transform (FT) spectroscopy is a versatile technique for studying the infrared (IR) optical response of solid-, liquid-, and gas-phase samples. In standard Fourier transform infrared (FT-IR) spectrometers, a light beam passing through a Michelson interferometer is focused onto a sample with condenser optics. This design enables us to examine relatively small samples, but the large solid angle of the focused infrared beam makes it difficult to analyze angle-dependent characteristics. Here, we design and construct a high-precision angle-resolved reflection setup compatible with a commercial FT-IR spectrometer. Our setup converts the focused beam into an achromatically collimated beam with an angle dispersion as high as 0.25°. The setup also permits us to scan the incident angle over ∼8° across zero (normal incidence). The beam diameter can be reduced to ∼1 mm, which is limited by the sensitivity of an HgCdTe detector. The small-footprint apparatus is easily installed in an FT-IR sample compartment. As a demonstration of the capability of our reflection setup, we measure the angle-dependent mid-infrared reflectance of two-dimensional photonic crystal slabs and determine the in-plane dispersion relation in the vicinity of the Γ point in momentum space. We observe the formation of photonic Dirac cones, i.e., linear dispersions with an accidental degeneracy at Γ, in an ideally designed sample. Our apparatus is useful for characterizing various systems that have a strong in-plane anisotropy, including photonic crystal waveguides, plasmonic metasurfaces, and molecular crystalline films.

A non-periodic sample, which also contains a periodic structure with a period smaller than the resolution limit of the optical microscope used for imaging it, was illuminated with the cone of white-light produced by a ring-shaped condenser with a numerical aperture larger than the objective lens. By rotating a slit placed at the back focal plane of the objective lens, we obtained several pairs of real plane and Fourier plane images corresponding to different diffraction directions. We simulated, discussed, and demonstrated a numerical algorithm capable of producing a high-resolution image of the sample after processing the experimental images.

At present, the Fresnel lens are commonly used as the condenser in high-concentrating photovoltaic (HCPV) modules. It is ideally believed that the output power of a III–V triple-junction solar cell which is placed on the focal plane of a Fresnel lens is the largest, because the intensity of the sunlight on the focal plane is the largest. Actually, according to our work, the dispersion of sunlight through a Fresnel lens and the nonparallelism and divergence of the incident light will lead to changes in the spectrum and the homogeneity of illumination, and cause a drop of the solar cell output. In this paper, the influence of the dispersion and nonparallel incidence of the light on the output of a triple-junction solar cell at different positions near the focal plane were theoretically studied, combined with the light-tracing simulation method and triple-junction solar cell circuit network model. The results show that the III–V triple-junction solar cell has the highest output power in both sides of the focal plane positions. The output power can be increased by about 15% after being optimized. The simulation results were verified by the experiments.

We developed a laboratory-size three-dimensional water-window x-ray microscope using condenser and objective grazing incidence Wolter type I mirrors, an electron-impact-type x-ray source, and a back-illuminated CCD. The imaging system was improved for practical applications in life science research fields. Using a new objective mirror with reduced figure errors, a resolution limit of 3.1 line pairs/μm was achieved for two-dimensional transmission images and sub-micrometer-scale three-dimensional structures were resolved. Incorporating a cryogenic stage into the x-ray microscope, we observed biological samples embedded in ice to evaluate the usefulness of observation in the water-window region and multi-energy observation was demonstrated using an x-ray source with multiple x-ray tubes.

Ellipsoidal monocapillary x-ray optics are used as condenser lenses in full-field transmission x-ray microscopy. The numerical aperture (NA) of the ellipsoidal monocapillary is designed to match that of the x-ray zone plate objective. In practice, monocapillaries have inner-surface errors that lead to mismatches between the monocapillary and the zone plate. In this study, mathematical models of monocapillaries with elliptic cross-section deformation and centreline straightness errors were developed, respectively. Furthermore, the optical properties of these monocapillaries were simulated based on a ray-tracing method. The simulation provides a qualitative picture of the NA and illumination angle distributions of the ellipsoidal monocapillary with inner-surface errors, and it is useful for predicting the inner-surface imperfections from the x-ray ring behind the monocapillary.

Partially coherent optical diffraction tomography (PC-ODT) is a well-established label-free quantitative three-dimensional (3D) imaging technique based on the refractive index (RI) contrast by measuring the intensities at multiple axially displaced planes. The imaging performance of tomographic RI microscopy is determined by the inversion of phase optical transfer function (POTF) which depends on the illumination pattern of imaging system. Here, we propose the optimization analysis of illumination pattern in PC-ODT, and the custom-build quantitative criterion is demonstrated to maximize the performance of POTF related to the “goodness” evaluation of an illumination aperture. Source modulation with different segment scale and gray scale is implemented to acquire arbitrary distribution source, and the corresponding 3D POTF can be easy obtained through the numerical incoherent superposition of each segment components. Moreover, the metrics of 3D POTF for various illuminations over the condenser aperture are analyzed. We test the obtained optimal illumination by imaging both a simulated micro phase bead and a real control bead sample, suggesting superior performance over other suboptimal patterns in terms of both SNR and spatial resolution. Further, experimental result based on unstained MCF-7 cell clusters is presented support this finding as well, and the proposed method is expected to find versatile applications in biological and biomedical research.

A single bounce ellipsoidal glass monocapillary was designed and fabricated and its performance was measured by both an optical measurement and an X-ray test. This monocapillary had a slope error of 17 μrad. The images of the focal spot and the far-field pattern recorded by a CCD detector showed that this fabricated monocapillary had high quality and satisfied the requirement of the designed data for X-ray nano-imaging.

The uniformity of the receiver surface energy flux density in the reflective high-power concentration photovoltaic system can affect the photoelectric conversion efficiency of the photovoltaic cell, and even cause the “hot spot” to damage it. In this paper, the plane mirror array algorithm is used to design a reflective high-power condenser, and TRACEPRO is used to numerical simulation study the uniformity of receiver surface energy flux density. The results show that the uniformity is greater than 99%, the experimental result (96.907%) is in agreement with the simulation results. In addition, the relationships of the effective area of the photoelectric conversion, the average irradiance, the maximum irradiance and the focal length are studied, and in the case of theoretical concentration ratio C is unchanged, the effective area of the photoelectric conversion is unchanged, the relationship of the maximum irradiance E max with the focal length f is E max = a + b ln ( f - c ) , and the relationship of the average irradiance E ave with focal length f is also E ave = a + b ln ( f - c ) .

A micro X-ray fluorescence setup was presented, based on an ellipsoidal capillary and a traditional laboratorial X-ray source. Using Ray-tracing principle, we have simulated the transmission path of X-ray beam in the ellipsoidal capillary and designed the optimal parameters of the ellipsoidal capillary for the micro X-ray fluorescence setup. We demonstrate that ellipsoidal capillary is well suited as condenser for the micro X-ray fluorescence based on traditional laboratorial X-ray source. Furthermore, we obtain the 2D mapping image of the leaf blade sample by using the ellipsoidal capillary we designed.

Fourier plane imaging (FPIM) and Fourier ptychographic (FPM) microscopy techniques were used to image photonic crystals. A computer-controlled hemispherical digital condenser provided required sample illumination with variable inclination. Notable improvement in image resolution was obtained with both methods. However, it was determined that the FPM technique cannot surpass the Rayleigh resolution limit when imaging photonic crystals.

This research reports a new product form made of nanofibers and the method used to produce it. Nanofibers are electrospun into a web form on a moving collector and the web is continuously transformed into a bundle by passage through a condenser. Since the web is made of loops of nanofibers and peeled off from the collector surface, the condensed bundle deforms very easily and is too weak for further processing. Thus, the bundle is drafted through a roller drafting system to improve the fiber array in the bundle length direction in various levels of draft temperature, since the temperature may affect the bundle drafting process and thus the bundle properties. Using a newly designed system, we tried to produce nanofibrous bundle of polyvinylidiene difluoride. The nanofiber arrangement and the tensile properties of the bundle were measured before and after the roller drafting process under various conditions. Results showed that the technology suggested in this paper had the feasibility to manufactur...

We have developed a cryogenic target for use at the High Intensity γ-ray Source (HIγS). The target system is able to liquefy 4He at 4 K, hydrogen at 20 K, and deuterium at 23 K to fill a 0.3 L Kapton cell. Liquid temperatures and condenser pressures are recorded throughout each run in order to ensure that the target's areal density is known to ∼ 1 %. The target is being utilized in a series of experiments which probe the electromagnetic polarizabilities of the nucleon.

A tabletop scanning electron microscope (SEM) utilizes permanent magnets as condenser lenses to minimize its size, but this sacrifices the tunability of condenser lenses such that a tabletop system can only be operated with a fixed accelerating voltage. In contrast, the traditional condenser lens utilizes an electromagnetic coil to adjust the optical properties, but the size of the electromagnetic lens is inevitably larger. Here, we propose a tunable condenser lens for a tabletop SEM that uses a combination of permanent magnets and electromagnetic coils. The overall dimensions of the newly designed lens are the same as the original permanent magnet lens, but the new lens allows the tabletop SEM to be operated at different accelerating voltages between 1kV and 15kV.

The problem that is posed byphase-only" objects, such as epithelial cells, for brightfield microscopy has resulted in development of several specialized imaging techniques including phase-contrast and DIC. In the past decades there has been increasing research on quantitative phase imaging (QPI), which enables real-time cellular dynamics to be visualised and the 3-D morphology to be quantitatively measured. It has previously been demonstrated that the DIC and phase-contrast images can be computationally generated using the phase-image provided by QPI. Recently, we have extended this approach to include Rheinberg. Although not as popular as phase contrast or DIC, Rheinberg illumination provides a form of label-free optical staining by introducing a multi-color filter into the condenser plane of the microscope, enabling different features within the cell to be stained with different colors depending on their spatial-frequency content. We recently developed a theory for image formation with Rheinberg illumination under the conditions of Kohler illumination from which an algorithm was developed that could simulate this process using the QPI image as input. In this paper we review and further develop this approach by testing it with multiple different modalities for recording the QPI image, namely digital holographic microscopy, which uses coherent illumination and spatial light interference microscopy, which makes use of white light. We examine a variety of samples including diatom and epithelial cells using a number of microscope objectives with different numerical apertures.

The project of transmission x-ray microscope (TXM) with tender x-ray is undergoing as an extension project of the soft x-ray tomography (SXT) endstation at Taiwan Photon Source (TPS). This TXM is aimed for energy from 1.5 keV to 2.4 keV and with phase contrast with the x-ray energy of 2.4 keV. As the extension of current SXT project, the beamline will be equipped with a variable line spacing (VLS) grating with the multi-layer coating which will be optimized for 2.4 keV. This TXM will be zoneplate based with a phase ring and capillary condenser. In order to match the field of view and numerical aperture (NA) of zoneplate with the emittance of the source in vertical direction, some compromise should be made. To match the low emittance of vertical direction, the NA of zoneplate should be lower and vertical of the secondary source should be larger. This will lower spatial resolution and energy resolution. The targeting resolution of this TXM for phase contrast will be 50nm and FOV is 20 μm. For the detector, which is currently design with a scintillator with a CCD detector. For the future, the direct detector for small pixel and high signal to noise ratio can be obtained. The other components of TXM, such as stages, cryo system, which can be shared with current SXT system which works under the energy of the water window region. This endstation for tender X-ray will be commission in 2020. The detailed design and current progress will be discussed in this presentation.

Conventional imaging systems suffer from a trade-off between the field of view and resolution. To overcome this limitation, we demonstrate dynamic gigapixel imaging via synthetic aperture microscopy. Integration of low magnification high numerical aperture condenser lenses enable submicron resolution live imaging over an extended field of view. Based on holographic measurements, image reconstruction is realized in real time enabling truly live imaging. Recent developments in the field of Fourier Ptychography have demonstrated gigapixel imaging via multiple image acquisitions and iterative reconstruction algorithms.

Total internal reflection fluorescence excitation (TIRF) microscopy allows the selective observation of fluorescent molecules in immediate proximity to an interface between different refractive indices. Objective-type or prism-less TIRF excitation is typically achieved with laser light sources. We here propose a simple, yet optically advantageous light-emitting diode (LED)-based implementation of objective-type TIRF (LED-TIRF). The proposed LED-TIRF condenser is affordable and easy to set up at any epifluorescence microscope to perform multicolor TIRF and/or combined TIRF-epifluorescence imaging with even illumination of the entire field of view. Electrical control of LED light sources replaces mechanical shutters or optical modulators. LED-TIRF microscopy eliminates safety burdens that are associated with laser sources, offers favorable instrument lifetime and stability without active cooling. The non-coherent light source and the type of projection eliminate interference fringing and local scattering artifacts that are associated with conventional laser-TIRF. Unlike azimuthal spinning laser-TIRF, LED-TIRF does not require synchronization between beam rotation and the camera and can be monitored with either global or rolling shutter cameras. Typical implementations, such as live cell multicolor imaging in TIRF and epifluorescence of imaging of short-lived, localized translocation events of a Ca2+ -sensitive protein kinase C α fusion protein are demonstrated.

Current LED based structured illumination projectors use commercial objective lenses to project the pattern, leading to an increased size of the projector. We present a compact, pseudo-random pattern generator with an enhanced field of view (FOV) of 60° × 60° to project structured light for machine vision applications. The miniaturization of optics is achieved by utilizing the multi-aperture approach. Currently such multi-aperture projection optics have an FOV of about 20°. Enlarging the FOV of microlenses results in higher geometric aberrations. Aberration correction for wide FOV is done by distributing the optical power over several microoptical surfaces, as in traditional optical systems, leading to a design of stacked microoptics. The correction of dominant aberrations like astigmatism is done by employing anamorphic microlenses. Further enhancement of the FOV is achieved by continuously varying the FOV of the individual lenslets over the microlens array (MLA). Thus, every channel of the array projects light to a different region of the image plane, resulting in a symmetric and continuous filling of the FOV across the image field. Consequently, anamorphic irregular or 'chirped' MLAs with lenslets of varying focal length and orientation depending upon its location in the MLA are designed. This also requires the projection optics to be illuminated with a field dependent incidence for which a two lens condenser optic is designed. A regular condenser lens array couples the light into the channels similar to the scheme for Kohler illumination, while the stacked microoptics along with a bulk field lens image the slide object on to the projection plane. A corresponding prototype with stacked and chirped microoptics with buried apertures and slide structures is realized using advanced reflow technology and characterization of such an arrayed pattern projector is presented.

Critical biomarkers of disease are increasingly being detected by point-of-care assays. Chemiluminescence (CL) and electrochemiluminescence (ECL) are often used in such assays due to their convenience and that they do not require light sources or other components that could complicate or add cost to the system. Reports of these assays often include readers built on a cellphone platform or constructed from low-cost components. However, the impact the optical design has on the limit of detection (LOD) in these systems remains unexamined. Here, we report a theoretical rubric to evaluate different optical designs in terms of maximizing the use of photons emitted from a CL or ECL assay to improve the LOD. We demonstrate that the majority of cellphone designs reported in the literature are not optimized, in part due to misunderstandings of the optical tradeoffs in collection systems, and in part due to limitations imposed on the designs arising from the use of a mobile phone with a very small lens aperture. Based on the theoretical rubric, we design a new portable reader built using off-the-shelf condenser optics, and demonstrate a nearly 10× performance enhancement compared to prior reports on an ECL assays running on a portable chip.

A novel digital radio-frequency (RF) condenser microphone system is proposed. Condenser microphones using the audio-frequency (AF) implementation method basically suffer from their high impedance sensor circuitry. The RF implementation method solves this problem. In RF condenser microphones, the inherent impedance can be lowered leading to superior noise performances. Since state of the art RF microphones are still entirely analog, a digital approach is presented which can further increase the demodulation linearity and can circumvent the 1/f noise as well as additional analog disadvantages.