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The present work involves the preparation of pure ZnO and gadolinium‐doped ZnO nanoparticles with the general formula GdxZn1−xO (X = 0–0.05) by wet chemical coprecipitation technique. XRD outcomes confirmed that these nanoparticles exhibited a hexagonal wurtzite structure of zinc oxide lacking any secondary phase. The calculated average crystallite size declined from 33 to 28 nm. Through SEM analysis, the shape and morphology of the sample were determined, which showed nanoflakes‐like structures, and EDS analysis confirmed the elemental composition of Gd‐doped ZnO nanoparticles. UV–vis DRS spectral studies indicate good optical capabilities with a decline in the bandgap from 3.4 to 2.6 eV with an incline in doping concentration. Photoluminescence studies exhibited a green emission peak at 378 nm. Additionally, photodegradation of these nanoparticles was assessed through degradation of MB dye, which showed 94% of dye degradation. Synthesized nanoparticles show good electrochemical performance in CV studies. Pure ZnO and Gd‐ZnO were examined against Gram‐positive Enterococcus faecalis and Gram‐negative Escherichia coli bacteria, and it was initiated that the zone of inhibition of antibacterial activity improved with gadolinium doping compared to the pure ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

The development direction of advanced solid-state lasers is higher output power and better beam quality. Rare earth ion doped yttrium aluminum garnet transparent ceramics are preferred materials for solid-state laser gain media, but thermal effects during the pumping process deteriorate the beam quality and hinder further increase in output power. The heat generation and dissipation of laser ceramics with complex configurations are more uniform during the pumping process, which can significantly reduce thermal effects. Compared with traditional preparation methods, 3D printing is able to form more complex design structures, suppress thermal effects, and achieve integration and miniaturisation of multi-module devices, driving lasers towards a wider range of applications. In this paper, several traditional methods for the preparation of laser ceramics with complex configurations are introduced firstly, and the advantages and limitations are analyzed. Then, the research status and problems in 3D printing yttrium aluminum garnet-based laser ceramics are systematically reviewed. Common 3D printing methods include direct ink writing, stereolithography, digital light processing, material jet printing, two-photon polymerization and micro-continuous liquid interface printing. Among them, there are interlayer defects in the samples printed by stereolithography and digital light processing, resulting in severe scattering losses. Material jetting printing combined with dry pressing can be used to manufacture planar waveguides. Two-photon polymerization and micro-continuous liquid interface printing are suitable for the fabrication of highly complex structures at micrometer scales. Direct ink writing not only enables the fabrication of laser ceramics for the first time, but also has the most extensive relevant research and is still the most promising method for the preparation of laser ceramics with complex configuration. At the end of this paper, the current problems and research prospects of yttrium aluminum garnet-based laser ceramics prepared by 3D printing are summarized. [ABSTRACT FROM AUTHOR]

The MIllimeter Sardinia radio Telescope Receiver based on Array of Lumped elements KIDs, MISTRAL, is a cryogenic LEKID camera, operating in the W band ( 77 - 103 GHz ) from the Gregorian focus of the 64-m aperture Sardinia Radio Telescope (SRT), in Italy. This instrument features a high angular resolution ( ∼ 12 arcsec ) and a wide instantaneous field of view ( ∼ 4 arcmin ), allowing continuum surveys of the mm-wave sky with many scientific targets, including observations of galaxy clusters via the Sunyaev–Zel'dovich effect. In May 2023, MISTRAL has been installed at SRT for the technical commissioning. In this contribution, we will describe the MISTRAL instrument focusing on the laboratory characterization of its focal plane: a ∼ 400 -pixel LEKID array. We will show the optical performance of the detectors highlighting the procedure for the identification of the pixels on the focal plane, the measurements of the optical responsivity and NEP, and the estimation of the optical efficiency. [ABSTRACT FROM AUTHOR]

This work demonstrates facile synthesis of Tb-doped ZnO nanoparticles and investigates their structural, optical, electrochemical, photocatalytic, and antibacterial performance. XRD patterns of undoped and doped ZnO nanoparticles confirm a hexagonal wurtzite structure. TEM and SAED reveals that the particle size is 14–38 nm. SEM images show that ZnO and Tb-doped ZnO nanoparticles have smooth surfaces, and elemental composition was confirmed by EDX analysis. UV–Visible spectrophotometry studies, reveals that the band gap narrows with increasing Tb concentration. Photoluminescence spectra at room temperature showed a band at 538 nm, indicating zinc vacancies and green emission. Tb-doped ZnO with x = 0.075 exhibited the highest photocatalytic activity for degrading Rose Bengal dye compared to other photocatalysts. The electrochemical behaviour of Catechol (CC), Hydroquinone (HQ), and Bisphenol-A (BPA) at Tb–ZnO/MCPE was studied. The modified electrode process for CC and BPA was adsorption-controlled, and simultaneous recognition of CC, HQ, and BPA was achieved, showing an increase in current. Electro polymerization of poly (Congo red) on Tb–ZnO/MCPE confirmed clean deposition on the surface, enhancing electrocatalytic activity. The antibacterial efficacy was tested using the traditional disc diffusion method, showing effective inactivation of bacterial strains, including pathogens such as S. aureus (G+) and E. coli (G-). [Display omitted] • This work demonstrates the facile synthesis of ZnO and Tb doped nanoparticles via chemical co-precipitation process. • The XRD pattern appearance hexagonal wurtzite structure. TEM and SAED reveal particle sizes of 14–38 nm. SEM and EDX confirm morphology and elemental composition. • Higher Tb doping exhibit the highest photocatalytic activity in degrading Rose Bengal dye. And the antibacterial activity, tested via disc diffusion, effectively inactivates S. aureus (G+) and E. coli (G−) bacterium. • The sweep rate confirms that the modified electrode process of CC and BPA at the PCRTZO/MCPE was adsorption controlled. Tb–ZnO/MCPE electrode simultaneously detects CC, HQ and BPA with distinct current increases. • Electro polymerization of poly (Congo red) on Tb–ZnO/MCPE confirms Congo red deposition on the electrode surface. [ABSTRACT FROM AUTHOR]

The transmittance and surface smoothness of SnO2 thin films directly affect the performance and use of optical devices, while sputtering conditions determine the morphology and optical properties of SnO2 thin films. In order to study the effect of sputtering conditions on the morphology and optical properties of SnO2 films, the FJL-560 Magnetron sputtering system was used to prepare SnO2 films at different sputtering temperatures on silicon and glass substrates. The results show that the sputtering temperature has a significant impact on the crystallinity of SnO2 thin films. Silicon-based SnO2 thin films can achieve the optimal crystallization state at room temperature, while glass-based SnO2 thin films have an optimal crystallization temperature of 250 °C. The higher the sputtering temperature, the larger the grain size of the thin films; The substrate and temperature did not have a significant impact on the Raman spectrum peak position and waveform of SnO2 thin films, while the Raman spectrum peak intensity of glass substrate was significantly stronger than that of silicon substrate; The average transmittance of SnO2 thin film can reach around 80%, and as the sputtering temperature increases, the transmittance of the film decreases. [ABSTRACT FROM AUTHOR]

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A bio‐based nanocomposite optical film was obtained through a simple sol‐gel process and solution casting. The dispersion effect of cellulose nanocrystals (CNCs) gel and the optical properties, mechanical performance and thermal stability of CNC‐doped cellulose triacetate (TAC) films (TAC−X) were systematically evaluated. The results show that CNCs can be well dispersed in hydrophobic organic solvents and TAC matrices through the sol‐gel process. TAC−X film has excellent optical properties, its light transmittance is above 92 %, its haze value and birefringence are low, ranging from 0.21±0.01 % to 0.38±0.02 %, and (1.64±0.26)×10−6 to (2.49±0.50)×10−6 respectively. When doped with 2 wt % CNCs, the tensile strength and Young's modulus of the TAC‐2 film were 33.0 % and 30.1 % higher than those of the pure TAC film, separately. At the same time, the TAC−X film also maintains good thermal stability, with its glass transition temperature and maximum decomposition temperature falling between 215–216 °C and 366–368 °C respectively. The simple sol‐gel process provides a convenient and efficient way to use CNCs doping to enhance the physical and mechanical properties of TAC optical films. [ABSTRACT FROM AUTHOR]

The antibacterial microcapsules were prepared by encapsulating Toddalia asiatica (L.) Lam. extracts with urea–formaldehyde resin. The orthogonal test was designed to investigate the effects of the mass ratio of core and wall materials (Wcore:Wwall), emulsifier concentration, reaction temperature and reaction time on the yield rate and coverage rate of microcapsules, and to obtain the best preparation technology for microcapsules. The single-factor results indicated that the maximum influence factor was the Wcore:Wwall of the microcapsules; the larger the Wcore:Wwall, the easier the microcapsules were to agglomerate; and when the Wcore:Wwall was 0.8:1, the coverage rate reached the maximum value of 11.0%. The waterborne topcoat paint film was prepared by adding the microcapsules in the same content. The yield rate, coverage rate, and microscopic morphology of Toddalia asiatica (L.) Lam. extract microcapsules were analyzed, as well as the effects of microcapsules on the microscopic morphology, optical properties, cold liquid resistance, mechanical properties and antibacterial properties of a waterborne topcoat paint film. Combining the optical properties, cold liquid resistance, physical properties, and antibacterial properties of the waterborne topcoat paint film, the comprehensive performance of the waterborne topcoat paint film with the Wcore:Wwall of 0.8:1 was superior. The gloss was 8.07 GU, color difference ΔE was 9.21, visible light transmittance was 82.90%, resistance to citric acid, ethanol and detergent were grade 1, 2 and 2, respectively, elongation at break was 15.68%, and roughness was 3.407 µm. The antibacterial activity against Escherichia coli and Staphylococcus aureus were 42.82% and 46.05%, respectively. In this study, a waterborne topcoat paint film with a microcapsule-coated plant-derived antibacterial agent as the core was prepared, expanding the application prospect of plant-derived antibacterial microcapsules. [ABSTRACT FROM AUTHOR]

Sapphire optical components are prone to cracks and scratches during grinding, installation, and service, which affects the laser damage resistance. In order to improve the laser damage resistance of sapphire damaged surface, the influence of surface damage on the laser damage resistance was analyzed. The repair mechanism of wet etching on the damaged surface was expounded. The results show that the reduction of damage frequency and depth can reduce the LIMF, and the LIMF caused by ellipsoidal damage is less than prism damage. The texture direction relationship between the two surfaces influences the internal LIMF. Compared with the vertical surface damage, the parallel surface damage has a larger LIMF value. The LIMF value of the etching surface is minimal. The characteristics of the damaged surface before and after etching were compared. The results show that the surface damages are passivated and merged after etching, and the surface transforms into ellipsoidal features. These changes are conducive to improving the laser damage resistance. Finally, the effect of the etching process on surface quality is analyzed. The formation mechanism and etching repair mechanism of sapphire damaged surface at the atomic scale were revealed by molecular dynamics simulation. Finally, the laser damage resistance of sapphire surface was tested, and the feasibility of wet etching was verified. [ABSTRACT FROM AUTHOR]

Biaxially oriented polyamide 6 (BOPA6) films were prepared by extrusion casting and biaxial stretching with polyamide 6. The effects of different biaxially oriented on the macroscopic properties of BOPA6 were investigated by characterizing the rheological, crystallization, optical, barrier and mechanical properties. The results show that the increase of stretching temperature leads to the diffusion and regular stacking rate of BOPA6 chain segments towards crystal nuclei increases, the relative crystallinity increases, reaching 27.87% at 180 °C, and the mechanical strength and optical performance decrease. Heat-induced crystallization promotes the transformation of β-crystals to α-crystals in BOPA6, resulting in a more perfect crystalline structure and enhancing oxygen barrier properties. BOPA6 chains are oriented, and strain-induced crystallization (SIC) occurs during the biaxial stretching. Further increasing the stretch ratio, the relative crystallinity increased to 30.34%. The machine direction (MD) and transverse direction (TD) tensile strength of BOPA6 (B-33) are nearly two times higher than the unstretched film, reaching 134.33 MPa and 155.28 MPa, respectively. In addition, the permeation decreases to 57.61 cc·mil/(m2 day), and the oxygen barrier performance has improved by nearly 30% compared to the sample B-22. BOPA6 has a high storage modulus at a high stretching rate (300%/s). Rapid chain relaxation would promote the molecular chain disorientation, destroy the entangled network of the molecular chain, and lead to a decrease in tensile strength, reducing to about 110 MPa. [ABSTRACT FROM AUTHOR]

Polyamide 66 was extensively utilized in various applications contributed by its excellent mechanical performance and outstanding durability. However, its high crystallinity renders it to have low transparency, which seriously limits its application in optical devices. Herein, a highly transparent polyamide (PA) 66-based copolymer was reported using 4,4′-diaminodicyclohexylmethane (PACM), adipic acid, and polyamide 66 salt as the reaction monomers. Wide-angle X-ray diffraction (WAXD) analysis revealed that the crystal phase of the synthesized PA66/PACM6 displayed a clear transition from α to γ as the PACM6 increased accompanied by a decreased intensity in the diffraction peak of the copolymer, whose transmittance was successfully adjusted reaching as high as 92.5% (at 550 nm) when the PACM6 was 40 wt%. Moreover, the copolymer with a higher content of PACM6 exhibited larger toughness. On the other hand, the biaxially oriented films of PA66/PACM6 (20 wt%) were also prepared, and it was found that the transparency of the PA66/PACM6 copolymer could be further enhanced via adjusting the stretching ratio of the film. Furthermore, the mechanical strength of the biaxially oriented PA66/PACM6 was also improved with the increase in the orientation degree in the stretching process, indicating that the physical properties of the transparent PA66 were significantly influenced by its alicyclic structure, and the introduction of PACM into PA66 was capable of effectively improving the optical and crystalline characteristics of PA66, revealing that the synthetic strategy has great potential for guiding the design and development of transparent polyamide materials. [ABSTRACT FROM AUTHOR]

The durability of thick solar glass mirrors has been evaluated in this study by exposing samples at two potential exposure sites. Samples have been exposed for a period of 18 months at different orientations (North, South, East, and West) to evaluate the impact of orientation on the durability. The samples performance has been evaluated by measuring the specular reflectance of the glass samples before and after an appropriate cleaning process. In addition, the contact angle and the surface energy have been analysed. Obtained results show that mirror durability is very specific to the environmental conditions of the exposure site.

AlON transparent ceramics have been widely used in many fields due to the excellent optical and mechanical properties. The development of AlON transparent ceramics was introduced in the paper, and the reasons affecting the light transmittance of ceramics were illustrated in terms of reflection, absorption, and scattering. The research status of the powder preparation, sintering aid system, molding technology, and sintering technology for the AlON ceramics were described in detail, the existing technical problems were analyzed, and the optimization directions were proposed.

The core optics in the deep-space high-energy physics ray detection system are an ultra-precision aspherical surface, which would generate surface errors introduced by the ultra-precision single point diamond turning (SPDT), leaving the millimeter-level length and micron-level height periodic mid-spatial frequency (MSF) errors dissatisfying the expected optical performance. Hence, a corrective technique is urgent to effectively remove MSF errors from optical surfaces, enhancing the compliance control of the tool to adapt to curvature-varying optical surfaces to obtain a stable Gaussian-like removal function. This study explored the sponge figuring processing (SFP) removal mechanism, which verified the robustness and removal efficiency of the tool influence function for the planar and various curvatures of the Ni–P surface. To comprehensively investigate the removal function of SFP, based on the sponge-figuring process removal mechanism with three removal regimes, the relative velocity model and contact pressure model are established and verified for validity by pre-experiment. To obtain a stable and effective removal function, L16 orthogonal experiments and analysis of variance (ANOVA) methods were conducted on flat specimen surfaces on a 3-axis ultra-precision figuring tester machine utilizing a sponge head with in-situ correction of high slurry absorption and retention capacity as the figuring tool. To determine the curvature surface impact on the robustness of the tool influence function (TIF), matching experiments of spatial wavelength and full width at half maximum (FWHM) were executed. As a result, the removal function is mainly impacted by the offset, accounting for 40%, and the error was 8% in the predicted value of the volume removal rate under the optimal parameter conditions. From the perspective of optical performance, the significant peak of 1D-power spectral density (PSD) was suppressed in the mid-frequency band, partially converted into high-frequency band errors, and the mid-frequency surface ripple error was effectively enhanced from 2.4 to 1.8 nm, following multiple iterative figuring, for the variable curvature surface. [ABSTRACT FROM AUTHOR]

A novel samarium-containing rare-earth organic macromolecular complex transmutation (Sm(CAHD)2, phen-co-MMA) was synthesized using a coordination reaction with rare earth sm3+ as the central luminescent ion, acrylamide, lauryl alcohol, and 8-hydroxyquinoline synthesized as the main ligand and phen as the co-ligand, and copolymerized with methyl methacrylate. The structure, optical properties, and thermal stability of Sm(CAHD)2, phen-coMMA were investigated by Elemental analysis IR, XPS, UV, fluorescence spectroscopy. XRD, TGA, and other testing methods. The results showed that the characteristic emission peaks of sm3+ appeared at 560 nm,620 nm, and 650 nm for Sm(CAHD)2 phen-coMMA under UV excitation at 315 nm, with the highest intensity at 650 nm and a good match with the photosynthesis spectrum performed by plants. The degradation temperature of the light conversion agents was 182 °C, which has good thermal stability. The synthesized light conversion agents has excellent optical properties and is not easily degraded at high temperatures, so it is expected to be used as a light conversion agent for agricultural films. [ABSTRACT FROM AUTHOR]

The world is emphasizing the need for building design that considers energy performance to deal with climate problems. South Korea has constantly been tightening the design standards for saving building energy but with a focus on thermal performance and equipment systems. Accordingly, this study conducted an energy simulation experiment on office buildings with different window-to-wall ratios (WWRs) to propose a smart glazing plan to improve energy performance. An energy simulation experiment was performed on office buildings with varying WWRs to hierarchically analyze the influence of building window performance elements, including the heat transmission coefficient (U-value), visible light transmittance (VLT), and solar heat gain coefficient (SHGC), on building energy performance. The analysis showed that SHGC had the most significant impact on the heating and cooling load, by 22.13%, with the influences of the variables being 12.4% for the U-value, 4.78% for VLT, and 82.83% for SHGC. The results showed that the solar heat gain coefficient (SHGC) had the greatest impact on energy performance among window performance elements, and the effect increased significantly in certain WWRs. Moreover, to improve the energy performance of buildings with higher WWRs, it is essential to reflect the optimum composition of the U-value and SHGC on the window plan. This study's findings propose measures to supplement existing window plans focusing on thermal performance. Furthermore, these results hold academic value in providing concrete grounds for that. [ABSTRACT FROM AUTHOR]

Performance of a solar reflector depends upon the topology of the reflector unit. Curved reflector certainly performs better but it has high-cost, high manufacturing complexity and sometimes even requires non-indigenous technology for its production. Besides, the flat plate solar reflecting unit (FSRU) offers low cost, are widely available and are indigenous in nature. The present work attempts to give a simple methodology to test different combinations of a large-scale FSRU under azimuthal sun alignment. The obtained result is validated with corresponding CAD model and previously performed experimental results. The FSRU is a funnel-type solar reflector in the form of an inverted frustum of a square pyramid. The path followed by the in the unit is classified in different categories, based on their interaction with reflectors. The results show that there is a good agreement between path of rays observed during experiment and path of rays predicted by a CAD software. The maximum deviation ( δ max ) in path for optical performance is 2.1%. On other hand the maximum uncertainty (χ) in path is 2.96% considering ± 1° error of manufacturing of FSRU. Thermal efficiency of FSRU is 69% considering reflectivity of 97% for the reflectors. The final output of the present study predicts that (a) amount of errors ( δ max and χ) are under control for large size of FSRU and (b) azimuthal alignment improves the FSRU's thermal performance. [ABSTRACT FROM AUTHOR]

Xiaoning Li,1– 3 Lun Pan,3 Weizhong Lan,3 Zhikuan Yang1– 3 1Optometry Department, Changsha Aier Eye Hospital, Changsha, Hunan, People’s Republic of China; 2Aier School of Ophthalmology and Optometry, Hubei University of Science and Technology, Xianning, Hubei, People’s Republic of China; 3Aier Institute of Optometry and Vision Science, Changsha, Hunan, People’s Republic of ChinaCorrespondence: Xiaoning Li, Optometry Department, Changsha Aier Eye Hospital, Changsha, Hunan, People’s Republic of China, Email lixiaoning@aierchina.comBackground: The aim of this study was to investigate the effects of applied forces generated by a rim screw on the optical performance of mounted myopia lenses. The residual refractive error and retinal image quality of the corrected eyes were also investigated.Methods: For 120 lenses, internal lens stress was measured using a newly designed digital strain viewer (colmascope). Sixty myopic adults (120 eyes) were recruited. The effects of internal lens stress on residual refraction and retinal image quality were evaluated using OPD Scan III. The results were compared between loose and tight mounting and between the right and left eyes.Results: Significant differences were observed among nine lens zones in both the right and left lenses, regardless of the mounting state (P < 0.001). The differences were mainly derived from the five vertically arranged zones (P < 0.05). Significant differences in internal lens stress were observed between the right and left lenses (P < 0.05). No significant differences in central residual refractive error and retinal image quality of the corrected eyes were found between the loose- and tight-mounted lenses.Conclusion: The applied forces generated by the rim screw changed the peripheral optical performance of the mounted myopia lenses but exerted only negligible impacts on the central residual refractive error and visual image quality.Keywords: myopia, colmascope, internal stress, optical performance, retina image quality

Using TracePro optical software, the differences in optical performance of solar cavity receivers with or without spiral tubes were simulated, and the effects of the reflectivity of inner wall of cavity and the outer diameter and pitch of the spiral tubes on the optical performance of receivers were investigated. Besides, the optical performance of four different receiver shapes were also compared. The results show that it is not proper to approximate the inner wall of the receivers as the outer surface of the spiral tubes, because this approximation cannot truly reflect the heat flux absorbed by the spiral tubes. When the pitch is constant, the reflectivity of the inner wall of the cavity is proportional to the amount of heat flux absorbed by the outer surface of the spiral tubes and the optical efficiency of the system. As the reflectivity is less than 0.8, the increase of the pitch can improve the optical performance of the receiver, while the opposite is true when the reflectivity exceeds 0.8. In addition, the truncated-cylindrical receiver has the best optical performance among the four different shapes of receivers, and its optical efficiency can reach as high as 85.42%. This research can provide theoretical guidance for the design and optimization of receivers, and lay a foundation for the analysis of heat transfer performance of receivers.

Abstract Introduction This study was performed to compare the optical performance of a multizonal presbyopia-correcting intraocular lens (IOL) and a conventional trifocal model. Methods The optical quality and simulated visual acuity (VA) of 570 Precizon Presbyopic NVA (OPHTEC BV) and AcrySof IQ PanOptix (Alcon) were compared. The Precizon features a refractive design consisting of alternating optical zones that converge the incident light into two principal foci and a transitional zone for intermediate vision. By contrast, the PanOptix applies a diffractive (non-apodized) profile to achieve trifocality. Simulated VA was derived from the modulation transfer function. Chromatic aberration effects were also studied. Results The diffractive and multizonal-refractive lenses yielded comparable simulated VAs at far focus (0.00 logMAR). All curves showed a reduction in expected VA with an increase in negative defocus. At − 1.0 D, the multizonal-refractive IOL's VA dropped by 0.05 logMAR, but for the diffractive model, it was one line (0.11 logMAR). The multizonal-refractive lens's VA prediction at the secondary peak was 0.03 logMAR—minimally better than the 0.06 logMAR of the diffractive lens at − 2.5 D. The refractive lens exhibited a 24% decrease in polychromatic optical quality due to material dispersion. The performance of PanOptix was more substantially affected, showing a 44% loss at 50 lp/mm at far, with minimal effects at other distances. Conclusion The multizonal-refractive lens does not fall short of the established trifocal IOL, and it can be used to extend the visual range of pseudophakic patients. Although the multizonal-refractive lens has lower material dispersion, the diffractive model corrects chromatism beyond far focus.

The possibility of achieving superior optical characteristics and passive athermalization in dual-band IR objectives of a simple design is shown. This is ensured, in particular, by using refractive lenses made of chalcogenide glasses in the optical scheme. Recommendations regarding the layout of the optical scheme and obtaining initial design parameters for the subsequent optimization are given. The reliability and effectiveness of the recommendations are confirmed by the results of designing a super-aperture refractive-lens objective operating in the mid- and long-IR subranges and forming a high-quality polychromatic image on the matrix of an uncooled microbolometer in the operating temperature range from – 40°C to + 60°C.

Polyaniline-silver chloride nanocomposites were prepared by in-situ chemical oxidation polymerization with polyaniline with good conductivity as substrate and photosensitive semiconductor material silver chloride as initiator, and their electrical and optical properties were systematically studied. The morphology, structure, optical properties, and conductivity of polyaniline monomer and polyaniline or silver chloride nanocomposites were characterized and compared by scanning the electron microscope, quaternary probe conductivity tester, and simulating sunlight illumination. The results show that polyaniline silver chloride nanocomposites have good thermal stability; nano-silver chloride particles are uniformly dispersed in polyaniline; the doping of silver chloride will have a positive effect on the conductivity of the composites. At the same time, silver chloride with surface metal plasma oscillation effect is doped in the composite material, which makes the composite material have excellent light absorption and catalytic performance. [ABSTRACT FROM AUTHOR]

This article presents a detailed analysis of parameters that affect the optical performance of parabolic trough solar collector (PTSC) and proposes a suitable method to optimize the relevant ones. A mathematical model is drafted and simulated for known geometry and parameters of industrial solar technology (IST) PTSC. The model was evaluated for three different configurations of IST PTSC involving distinct components. A comparison between the experimental results and model estimations indicates a maximum root-mean-square error (RMSE) of 0.7997, confirming the reliability of the proposed model. The influence of variations in absorber diameter (Dao), length (lrc), width (wrc), and focal length of PTSC (frc), along with direct normal incidence (In), dirt factors (ξdm, ξdhc), and angle of incidence (θ) on the optical performance of PTSC has been investigated. It was established that variation in mentioned parameters exhibits both positive and negative impacts on optical performance. After careful analysis, lrc, wrc, frc, Dao, and θ were chosen for optimization as it was perceived that by varying these in a reasonable range, an optimal set of parameters could be obtained that maximize the absorbed solar irradiation for a given PTSC. Genetic algorithm (GA), particle swarm optimization (PSO), and African vultures optimization algorithm (AVOA) are utilized to estimate the optimal values of parameters. Significant improvement in absorbed solar irradiation (~16%) is registered with optimized parameters, suggesting that benefits can be obtained if a study is performed prior to producing PTSC modules for an application. [ABSTRACT FROM AUTHOR]

In this study, a 50 × 50 mm holographic optical element (HOE) with the property of a spherical mirror was recorded digitally on a silver halide photoplate using a wavefront printing method. It consisted of 51 × 96 hologram spots with each spot measuring 0.98 × 0.52 mm. The wavefronts and optical performance of the HOE were compared with those of reconstructed images from a point hologram displayed on DMDs of different pixel structures. The same comparison was also performed with an analog-type HOE for a heads-up display and with a spherical mirror. A Shack–Hartmann wavefront sensor was used to measure the wavefronts of the diffracted beams from the digital HOE and the holograms as well as the reflected beam from the analog HOE and the mirror when a collimated beam was incident on them. These comparisons revealed that the digital HOE could perform as a spherical mirror, but they also revealed astigmatism—as in the reconstructed images from the holograms on DMDs—and that its focusability was worse than that of the analog HOE and the spherical mirror. A phase map, i.e., the polar coordinate-type presentation of the wavefront, could visualize the wavefront distortions more clearly than the reconstructed wavefronts obtained using Zernike polynomials. The phase map revealed that the wavefront of the digital HOE was more distorted than those of the analog HOE and the spherical mirror. [ABSTRACT FROM AUTHOR]

Introduction: This study was performed to compare the optical performance of a multizonal presbyopia-correcting intraocular lens (IOL) and a conventional trifocal model. Methods: The optical quality and simulated visual acuity (VA) of 570 Precizon Presbyopic NVA (OPHTEC BV) and AcrySof IQ PanOptix (Alcon) were compared. The Precizon features a refractive design consisting of alternating optical zones that converge the incident light into two principal foci and a transitional zone for intermediate vision. By contrast, the PanOptix applies a diffractive (non-apodized) profile to achieve trifocality. Simulated VA was derived from the modulation transfer function. Chromatic aberration effects were also studied. Results: The diffractive and multizonal-refractive lenses yielded comparable simulated VAs at far focus (0.00 logMAR). All curves showed a reduction in expected VA with an increase in negative defocus. At − 1.0 D, the multizonal-refractive IOL's VA dropped by 0.05 logMAR, but for the diffractive model, it was one line (0.11 logMAR). The multizonal-refractive lens's VA prediction at the secondary peak was 0.03 logMAR—minimally better than the 0.06 logMAR of the diffractive lens at − 2.5 D. The refractive lens exhibited a 24% decrease in polychromatic optical quality due to material dispersion. The performance of PanOptix was more substantially affected, showing a 44% loss at 50 lp/mm at far, with minimal effects at other distances. Conclusion: The multizonal-refractive lens does not fall short of the established trifocal IOL, and it can be used to extend the visual range of pseudophakic patients. Although the multizonal-refractive lens has lower material dispersion, the diffractive model corrects chromatism beyond far focus. [ABSTRACT FROM AUTHOR]

Concentrating solar thermal systems are widely used for industrial heat production. The state-of-the-art methods use different concepts among which tracking Fresnel mirrors or parabolic troughs. In the market however there are very few devices operating at intermediate to medium temperatures. In order to fill this gap, an innovative concentrating solar thermal system is studied in the frame of the Hellenic — German cooperation project “SCoSCo”. The proposed device concentrates the solar radiation to the receiver using a micro-mirror array. The scope of this paper is to present the optical simulation results of this innovative reflector, and compare the results obtained by different software packages. The optical performance assessed using Solstice ray-tracing software, yields a theoretical optical efficiency from 0.7 to 0.9. In order to evaluate the annual energy yield of the prototype, solar radiation data measurements in Patras, Greece for 2016 and were used as input. A three dimensional thermal model is developed in the COMSOL software to estimate the temperature distribution at the receiver. It was found that temperatures , ranged from 115 to 225 °C. The annual energy yield, calculated using the CARNOT toolbox ranges from 683 to 729 kWh.

Linear Fresnel solar collectors are a promising and emerging solution to contribute to renewable heat supply in industrial processes with thermal energy demand in the medium temperature range (2 was obtained with a direct normal solar irradiance of (870 ± 10) W/m2 in tests performed in May 2002, which is a result similar to that obtained in optical simulations of the system.

Age-related macular degeneration (AMD) causes severe vision impairments, including blindness. An option to improve vision in AMD patients is through intraocular lenses and optics. Among others, implantable miniaturized telescopes, which direct light to healthy lateral regions of the retina, can be highly effective in improving vision in AMD patients. Yet, the quality of the restored vision might be sensitive to the optical transmission and aberrations of the telescope. To shed light on these points, we studied the in vitro optical performance of an implantable miniaturized telescope, namely, the SING IMT™ (Samsara Vision Ltd., Far Hills, NJ, USA) designed to improve vision in patients affected by late-stage AMD. Specifically, we measured the optical transmission in the spectral range 350–750 nm of the implantable telescope with a fiber-optic spectrometer. Wavefront aberrations were studied by measuring the wavefront of a laser beam after passing through the telescope and expanding the measured wavefront into a Zernike polynomial basis. Wavefront concavity indicated that the SING IMT™ behaves as a diverging lens with a focal length of −111 mm. The device exhibited even optical transmission in the whole visible spectrum and effective curvature suitable for retinal images magnification with negligible geometrical aberrations. Optical spectrometry and in vitro wavefront analysis provide evidence supporting the feasibility of miniaturized telescopes as high-quality optical elements and a favorable option for AMD visual impairment treatments. [ABSTRACT FROM AUTHOR]

• A star-shaped receiver is designed for non-tracking operation of a concentrator. • The receiver is contained in an inexpensive single-layer glass tube. • The photothermal conversion performance of each sector of the star-shaped receiver was studied through optical simulation and experimental test. • The daily efficiency of the concentrator system is up to 77.38 %. In order to find an effective way to improve the performance of the non-tracking compound parabolic concentrator (CPC), this study presents the design evaluation and performance testing of a novel star-shaped receiver with an inexpensive single-layer glass tube. The optical model of the CPC was first established with the TracePro, and the influence of the incident angle on the optical performance of the CPC and the distribution of the energy flux density in each sector of the star-shaped receiver tube were determined. The results show that the rays receiving ratio and the concentration ratio of the CPC both decrease with the increase of the incident angle, when −13°≤ α ≤ 13°, the two parameters are 84.37 % and 64.32 %, respectively. Based on this, a testing bench was set up to test the photothermal conversion performance of the CPC under actual weather conditions. The influence of the air flow velocity on the photothermal conversion performance of the CPC, the outlet temperature and air flow velocity in each sector of the star-shaped receiver tube were tested and analyzed, and the potential correlation between them is discussed. When the air flow velocity changes from 1.7 m/s to 4.7 m/s, the daily efficiency of the CPC increases from 53.26 % to 70.71 %. It is found that air flow was not distributed evenly between six sectors of the star-shaped receiver tube trough it is symmetrical, so the outlet temperature and optical contribution ratio are different between six sectors. The results of the study provide a reference direction and data support for the optimization and application of the star-shaped receiver tube in non-tracking CPC. [ABSTRACT FROM AUTHOR]

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Optical measurement of display equipment has always been the most important means to evaluate its performance, and AR/VR and other Near‐Eye‐Display (NED) is a new type of display equipment. In recent years, its optical performance measurement methods and measuring equipment have been introduced, but the operation is complicated, the cycle is long and the cost is expensive. Therefore, this paper designs a method of measuring the main optical performance parameters of near eye display device based on binocular camera. According to the optical correlation principle of the display device, the derivation modeling, system design and calibration experiments were carried out, so as to realize the convenient, rapid and low‐cost measurement of the main optical performance parameters of the NED device. [ABSTRACT FROM AUTHOR]

In the Inertial Confinement Fusion facilities, single-point diamond fly-cutting and micro ball-end milling are the main techniques to fabricate the large-aperture KDP (KH 2 PO 4) optics and repair the surface defects on KDP, respectively. These machining processes inevitably generate various surface textures on the machined optics while the effect of these surface textures on the optical performance of machined optics has not been clarified yet. In this work, the light intensity modulation inside KDP machined by single-point diamond fly-cutting and micro ball-end milling processes was firstly analyzed and the characterizing methods of these machined surface textures were then investigated. It is found that the machining-caused surface textures with higher amplitude and smaller spatial period could result in more severe light intensity modulation inside KDP optic which has been acknowledged as one of the most important factors causing laser-induced damage to KDP. Moreover, the relative directions (i.e., parallel or perpendicular) between these textures on the front and rear surfaces of KDP could have a distinct effect on their light intensity modulation. For characterizing the texture structures, especially, texture direction, power spectrum density (PSD), and fractal dimension were adopted. The PSD analysis results indicate that the dominated textures on single-point diamond fly-cutting surfaces are mainly along the feed direction while the dominated textures on micro ball-end milling surfaces are perpendicular to the feed direction. These textures on micro ball-end milling surfaces have been identified as the residual tool marks whose period equals the step over of the milling process. The fractal dimension can precisely evaluate the machined surface roughness and texture directions. But in comparison, the angular spectrum of PSD has higher characterizing accuracy than the circumferential profile of the fractal dimension approach. [ABSTRACT FROM AUTHOR]

It is anticipated that perovskite solar cells (PSCs) will overtake other products in the market for next‐generation photovoltaics. The optical loss, however, continues to be a flaw that restricts the photocurrent (Jph) of PSCs. Mesoporous antireflection coatings (ARCs), both monolayer and multilayer, are designed using a combination of the finite element method and equivalent medium theory, and ARCs models are merged with PSCs. In the current work, mesoporous ARCs are made, the optical performance of the device is evaluated using optical modeling, and then the ARCs are integrated into solar cells. The simulation results show that the Jph of planar inverted PSCs can increase to 24.00 mA cm−2 when the front surface of PSCs adopts mesoporous ARC (via parameter optimization and sensible arrangement and combination). An increase of 0.98 mA cm−2 in Jph of PSCs is observed in comparison with flat ARC (23.02 mA cm−2). The strong light transmission and low reflection properties of the mesoporous ARCs are confirmed by the optimized solution. It is important to note that the first fusion of mesoporous and multilayer ARC offers a fresh approach to the development of perovskite and perovskite/silicon tandem solar cells with extremely high efficiency. [ABSTRACT FROM AUTHOR]

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Copyright of Iraqi Journal of Physics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• AgInS 2 QDs are successfully introduced into the ZIF-8 framework via microwave assisted-hydrothermal method. • With the help of the high porosity and stability of ZIF-8, the quenching issues due to the aggregation of QDs can be prevent. • ZnS shell is formed on the surface of AIS QDs by using ZIF-8 as zinc source, resulting in the effectively passivation of surface defects. • The luminous efficiency of AIS/ZIF-8 based WLED is 44.54 lm/W. Preparation of AgInS 2 quantum dots (AIS QDs) with high photoluminescence quantum yield (PLQY) and thermal stability remains an important challenge. In this paper, AIS QDs were successfully introduced into zeolitic imidazolate framework-8 (ZIF-8) by microwave-assisted hydrothermal method. Due to the effective isolation of the ZIF-8, the AIS QDs avoid the concentration quenching when they were assembled into white light emitting diodes (WLEDs) devices as color conversion materials. More importantly, the generation of ZnS layer between the interfaces of AIS QDs and ZIF-8 can efficiently improve the optical performance of AIS QDs, resulting in the fluorescence lifetime extended to 470.05 ns. Meanwhile, the PLQY of AIS/ZIF-8 composite reached up 34.30 % when microwave hydrothermal heating at 120 °C for 60 min with AgIn/Zn=1/3, which was higher than that of the pristine AIS QDs as 25.30 %. Finally, the WLED devices were fabricated by combining AIS/ZIF-8 composite fluorescent powder with (Ba, Sr)Si 2 O 2 N 2 :Eu2+ phosphors and blue LED. At 20 mA, the AIS/ZIF-8 based WLED shows the luminous efficiency (LE) of 44.54 lm/W, correlated color temperature (CCT) of 4242 K and color rendering index (CRI) of 89.1. Moreover, the Commission International de L'Eclairage (CIE) was (0.36, 0.35), indicating the WLED emited warm white light. The present strategy aims at enhancing the optical performance of AIS QDs, which also may trigger the development of QDs-based WLED. [Display omitted] [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO 2) nanoparticle-based thermochromic films are widely used in smart windows because of their favorable thermochromic and optical properties. The introduction of additional particles into VO 2 NP-based films enables the integration of their properties with those of the original films. This combination serves to modulate the optical performance of the films further. However, the impact of the incorporated particles on the optical performance of VO 2 NP-based thermochromic films has not been elucidated. In this study, the influence of particles with varying refractive indices, volume fractions, and sizes, when incorporated into VO₂ NP-based films, was calculated using the finite-difference time-domain (FDTD) method. The results indicate that an increase in the refractive index or the size of the incorporated particles led to an enhanced solar modulation ability (Δ T sol), albeit at the cost of reducing the luminous transmittance (T lum). Conversely, increasing the volume fraction of the particles did not significantly enhance the Δ T sol. Additionally, the introduction of additional particles into the film further reduces the total energy consumption by a maximum of 2.6 MJ/m2 compared to VO 2 NP-based films, according to EnergyPlus software analysis. Our findings offer new perspectives and recommendations for the development and practical implementation of thermochromic smart windows. • The impact of the incorporated particles on the optical performance of VO 2 NP-based thermochromic films was analyzed. • The Δ T sol of the film can be enhanced by increasing the refractive index or size of the incorporated particles. • The introduction of additional particles into the VO 2 NP-based film can further reduce the total energy consumption. [ABSTRACT FROM AUTHOR]