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This paper presents the measurement of the laser Threshold damage of an optical surface at different roughness coefficients. The study procedure is achieved through the manufacturing of two types of parallel-sided borosilicate plate (Glass Bk7, and SF13). The Laser used is ND: YAG pulsed laser and the longitudinal mode TEM00 laser pulses with pulse width τ =30ns and wave length λ=1.064μm, the laser beam is focused using F=30 mm lens. The concentrated laser beam is guided by a converging lens towards the optical surface of the parallel surface plate. Finally, we obtained a graph of roughness coefficient is drawn in relation the optical Threshold Damage of the optical surface, Before and after processing the optical surface. We were able to raise the threshold by about 15% after conducting thermal treatment of the optical surface

The application of coloured and optical glass in architecture is of great importance in terms of creating spatial dynamics and uniqueness of space. Dichroic glass is a type of glass coated with a thin layer of metal, which causes the glass surface to change in colour depending on the viewing angle. The colour of the glass depends on the incidence of different wavelengths of light passing through or bouncing off the glass surface, thus creating different effects of colour refraction. Created effects provide different possibilities in the design of buildings and improvements in the aesthetic quality of the interior space. This paper deals with the analysis and application of coloured dichroic glass in architecture and interior design.

In 1884 Otto Schott, Ernst Abbe and Carl and Roderich Zeiss founded the SCHOTT & Associates Glass Technology laboratory in Jena, Germany. Otto Schott’s target was to develop new glasses on optical positions defined by Ernst Abbe and high reproducible quality that would tremendously improve the image quality of Carl Zeiss microscopes and optical instruments. Prior to 1880, optical components were made from simple crown and flint glasses. The crown glasses were soda-lime silicates with low refractive indices and moderate Abbe numbers. The flint glasses were lead silicates with relatively low Abbe Numbers. By 1884 already two dozen flint and crown glasses were available for optical system designs. Still today photonics industry relies heavily on optical glasses to realize tightest optical design requirements of today photonics applications. The difference between today and the past is that the designer can choose from a variety of more than 120 optical glasses with differences in optical position, transmittance and very specific dispersion requirements.

Optical glass which usually has specific optical constants is the basic material of optical system of optical instruments and optical machinery. In order to accurately calculate the optical constants of optical glass, two models (PTT method and PTR method) were established for the quartz glass taking quartz glass as the research object. The application range and precision of the two methods were compared, and the influence of transmittance deviation on the accuracy of the two methods was analyzed. Both of the two methods have wide application scope and high accuracy. Under the influence of transmittance deviation, the PTR method has higher precision in calculating refractive index and the PTT method has higher precision in calculating absorption index. Therefore, the two methods are complementary to each other in resisting transmittance deviation.

The optical elements of image capturing and recording systems include filters, diaphragms, diffraction gratings, prisms, lenses, optical fibers, and mirrors. The latter are made of special optical glass with high property uniformity and no foreign inclusions, sweeps, bubbles, and so on.

A setup has been created, that allows to measure absorption coefficients in optically transparent materials by the photothermal common-path interferometry up to 10-6 см -1 which allows the separate determination of the surface and volume optical absorption coefficients. In the setup, absorption was detected in the K8 optical glass and the promising nonlinear crystal YCOB.

A number of process steps that build on one another are required to manufacture optical components from glass. The polishing steps are the most time-consuming and therefore cost-intensive parts of the process chain. Low removal rates and the depth of the Sub Surface Damage (SSD) to be removed contribute to this. An alternative for the complete removal of the SSD-penetrated material using contactless polishing methods such as Ion Beam Figuring (IBF) is the healing of the SSD. Due to the induced energy during laser-polishing, the material is remelted at the defects and the SSD are closed. However, laser-polishing is also associated with disadvantages in terms of shape accuracy and surface quality. The project HyoptO is therefore devoted to the development of a hybrid-process-chain consisting of laser processing and conventional polishing. It is expected that the healing times of the SSD can significantly reduce the process times in the subsequent polishing steps. However, there are a few questions to be answered regarding the economic use of the hybrid-process-chain. These include

This paper deals with the problem of replacing a thin lens by a thick lens with approximately the same properties as the thin lens. Equations enabling the calculation of the parameters of a thick lens that has the same focal length and the same value for one of the Seidel aberration coefficients (either the Seidel aberration coefficient of spherical aberration or the Seidel aberration coefficient of coma) as the thin lens are derived. A comparison of the proposed method for calculating the parameters of the thick lens with existing methods is given in examples. Further, the problem of replacing a thick lens made of optical glass with a given refractive index by another thick lens with a different refractive index but with the same focal length and the same Seidel aberration coefficient of spherical aberration is investigated.

The opportunities and special features of using a multi-purpose digital holographic camera (DHC) adapted for particle research for various diagnostic tasks, such as plankton investigation in its habitat, optical glass diagnostics, and study of defects in single crystals, are investigated. Experimental research with the DHC carried out and described in this paper has demonstrated the universality of the DHC measurement technology and its effectiveness for solving a number of diagnostic tasks in the study of small particles of different natures in various media.

Optical glass K9 is a critical kind of optical materials, however experiments have indicated that the mechanical grinding of K9 easily led to subsurface damage (SSD). Although substantial SSD measurement methods have been suggested, the problems including the prior knowledge of SSD and slow measurement speed still impede the reported method applications. To this end, this paper has presented an image-process-based method that can identify and measure the grinding-induced SSD in K9 specimens. By performing grinding trials, the method has been found to be able to accurately (with biggest relative error of 3.13% in comparison with the manually measured results) and quickly (with the measurement speed of 1.68 s per image) measure SSD depths. Without any parameter presetting, the method enables automatic SSD measurements, allowing the users without SSD knowledge to be able to use the method. Moreover, the method has shown the good robustness to the input image size, illumination, tilted specimen placement, and material flaws. The method is therefore anticipated to be meaningful for the industrial manufacturing, design and application of optical glass.

We present a review devoted to hybrid optical fibers, which combine the properties of conventional total internal reflection and antiresonant fibers and enable dispersion control at wavelengths where the material dispersion of the fiber host optical glass is normal. We discuss the main principles of mode propagation in such structures and show the prospects for their practical application.

In this paper, we propose a bi-ocular Head Up Display system using four lenses made up of two optical glass materials, which is compact and light weight. The initial component layout of the system is done using Petzval lens configuration and thin lens aberration formulae. To get rid of third and higher order aberrations rotational aspheric surfaces has been used.

To prevent the negative impact of external thermal actions on reliability of devices for measurement and thermal testing of objects of various physical nature the practical importance has electron beam processing of surfaces of optical elements has practical importance, because it prevents appearance of defects on the surface of elements which lead to a sharp degradation of performance of devices and their failures during operation. Aim: The aim of this research is to develop a method for improving the reliability of devices for measurement and thermal control of various physical nature objects by final electron-beam processing of optical elements. Materials and Methods: To study the influence of parameters of the electron beam on the properties of the surface layers of the optical glass elements of marks K8, K208, BK10 and ceramics marks KO1, KO2, KO3, KO5, KO12 used discs with a diameter of 3∙10-2…5∙10-2 m and thick 4∙10-3…6∙10-3 m, hemispherical cowl with diameter 4∙10-2…8∙10-2 m. For research was used developed specialized electron-beam equipment; the main characteristics of strip electron beam were as follows: width – 5∙10-4…5∙10-3 m, length – 6∙10-2…8∙10-2 m, density of thermal action – Fn = 5∙106…9∙108 W/m2 and velocity – V = 3∙10-3…10-1 m/s. Results: Experimental studies were held and found the critical values of external thermal actions (heat flux, time of action, etc.), the excess of which leads to the formation on the surface of negative defects that lead to their destruction. The results of the research determined the optimal range of change of parameters of the electron beam (density of thermal action Fn =7∙106…8∙108 W/m2 and the velocity V = 5∙10-3…5∙10-2 m/s) within which observed substantial improvement of the properties of the surface layers of the optical elements.

Для попередження негативного впливу зовнішніх термічних дій на метрологічні характеристики (точність, діапазони вимірювання та ін.) імпульсних лазерних далекомірів прицільних комплексів практичне значення має фінішна електронно-променева обробка поверхонь їх оптичних елементів, яка запобігає виникненню дефектів на поверхні елементів (тріщин, відшарувань, сколів, напливів та ін.), що призводять до різкого погіршення характеристик приладів та їх відмов при експлуатації. Метою роботи є покращення метрологічних характеристик імпульсних лазерних далекомірів при експлуатації в умовах зовнішнього термовпливу. Проведено експериментальні дослідження та встановлено критичні значення параметрів зовнішніх термодій (теплового потоку та часу його дії), перевищення яких призводить до утворення на поверхні елементів негативних дефектів, що призводять до їх руйнування. Встановлено оптимальні діапазони зміни параметрів електронного променю (густини теплової дії Fn = 7 106…8 108 Вт/м2 та швидкості переміщення V = 5 10-3…5 10-2 м/с), в межах яких спостерігається максимальне покращення властивостей поверхневих шарів оптичних елементів. При цьому не відбувається утворення негативних дефектів на їх поверхнях, збільшується коефіцієнт пропускання ІЧ-випромінювання елементами у 1,4…1,6 рази, що дозволяє збільшити точність та розширити діапазони вимірювання дальності імпульсними лазерними далекомірами у 1,2…1,5 разу. To prevent the negative impact of external thermal actions on metrological characteristics (precision, measurement ranges, etc.) of impulse laser rangefinders of sighting systems the practical importance is finishing electron-ray surface processing of optical elements, which prevents defects on the elements surface (cracks, delaminations, chips, flows etc.), leading to a sharp deterioration of devices and their failures during operation. The aim is to improve the metrological characteristics of impulse laser rangefinders when operating under conditions of external thermal impact. The experimental research is conducted and it established the critical values of external thermal impact (heat flow and time of its action), the excess of which leads to the formation on the elements surface the negative defects that lead to their destruction. The optimal ranges of changes of parameters of the electron ray (thermal action density Fn = 7 106…8 108W/m2 and the speed of movement V = 5 10-3…5 10-2 m/s), within which there is maximum improvement of properties of the surface layers of the optical elements. There is no formation of negative defects on their surfaces, it increases the transmittance coefficient of infrared radiation elements in 1,4...1,6 times, that lets to increase the accuracy and to expand the ranges of distance measurement by impulse laser rangefinders in 1,2 ... 1,5 times. Для предотвращения негативного влияния внешних термических воздействий на метрологические характеристики (точность, диапазоны измерения и др.) импульсных лазерных дальномеров прицельных комплексов практическое значение имеет финишная электронно-лучевая обработка поверхностей их оптических элементов, которая предотвращает возникновение дефектов на поверхности элементов (трещин, отслоений, сколов, наплывов и др.), приводящих к резкому ухудшению характеристик приборов и их отказам при эксплуатации. Целью работы является улучшение метрологических характеристик импульсных лазерных дальномеров при эксплуатации в условиях внешних термовоздействий. Проведены экспериментальные исследования и установлены критические значения параметров внешних термовоздействий (теплового потока и времени его воздействия), превышение которых приводит к образованию на поверхности элементов негативных дефектов, приводящих к их разрушению. Установлены оптимальные диапазоны изменения параметров электронного луча (густини теплової дії Fn = 7 106…8 108 Вт/м2 та швидкості переміщення V = 5 10-3…5 10-2 м/с), в пределах которых наблюдается максимальное улучшение свойств поверхностных слоев оптических элементов. При этом не происходит образование негативных дефектов на их поверхностях, увеличивается коэффициент пропускания ИК-излучения элементами в 1,4...1,6 раза, что позволяет увеличить точность и расширить диапазон измерения дальности импульсными лазерными дальномерами в 1,2...1,5 раза.

Introduction Portable ultrasound is a modality of medical ultrasonography that utilizes small and light devices, and is an established diagnostic method used in clinical settings such as Cardiology, Vascular Surgery, Radiology, Endocrinology, Pediatric and Obstetric & Gynecology. Presentation of cases We present a case report of 86-years old patient who underwent surgical rib fixation for multiple rib fractures followed by falling from standing height and our management experience. Discussion The use of portable ultrasound device in operation theatre demonstrates several advantages.We believe that Portable color doppler ultrasound system would be necessary in the management of rib fracture. Conclusion This study demonstrates that the portable ultrasound system is a valuable method of imaging in the assessment of rib fractures, and which can save time, economically affordable for many patients, and allow surgeons to make a minor incision in order to avoid complications such as infection, particularly in this group of vulnerable patients., Highlights • Portable ultrasound is a modality of medical ultrasonography. • Portable color doppler ultrasound system guiding might be valuable in assess-ment of rib fracture. • Elderly patients are highly susceptible to rib fractures after trauma.

An X-ray detector with a dielectric (KU1 optical glass) used as a sensitive element is described. Operation of the detector is based on the discovered effect of electric-field generation in a dielectric under exposure to radiation. The measurements were taken at the Angara-5-1 facility, at which the radiation source is megaampere Z-pinch plasma. It is shown that when the radiation power incident on the detector is approximately 1 MW/cm2, the detector response is a few volts with a time resolution of 1–2 ns. This effect is thought to be caused by “hot” electrons induced by radiation in the dielectric. The estimates for these experimental conditions are presented.

The paper describes a DF-OPTICS device that the present authors designed for the experimental study of changes in the optical properties of a glass whose surface is exposed to high-speed flows of micron-sized dust particles. The device allows the scattering indicatrix and the spectral transmittance to be automatically measured at each point of the sample with a 0.5-mm increment. Advantages of the developed device include small dimensions and the ability to work in vacuum, allowing it to be used in an accelerator chamber to simulate outer space factors. Experimental results for the K-8 glass put in a microparticle accelerator and bombarded by an aluminum powder PAP-1 with a characteristic size of 1-3 µm and speeds of 2-8 km / s are presented. The device makes it possible to measure the change of the spectral transmittance of transparent materials in the UV and RGB regions with an accuracy of 0.005%, which exceeds the sensitivity of some known spectrophotometers.

Measurement of the low damage threshold defects in a large aperture fused silica glass is of great significance. Currently, the popular characterization method for detecting the low damage threshold defects is via measuring the optical absorption of a fused silica glass using the surface thermal lensing technology. However the detecting area of a single shot in this method is too small, typically around 10×10 microns, so if a large aperture fused silica glass in the size of 400×400 mm is to be measured, it would take approximate 100000 hours to complete the measurement, which is obviously not acceptable. Here, we report a fast measurement technique for obtaining the low damage threshold defects in a large aperture fused silica glass according to its fingerprint spectrum, for the fused silica optical glass in the size of 400×400 mm, measurement of the low damage threshold defects in the whole surface in several hours is achievable.

The refractive index, Abbe number and transmittance are the most important properties of optical glass. Nevertheless, in many applications the spatial refractive index variation - called homogeneity – is of highest priority. The index homogeneity of optical glass is a key property in industrial metrology devices and professional movie cameras for example. These applications often use small to medium sized lenses produced from cold cuts or hot pressings. On the other side of the range, scientific instruments of large astronomical telescopes require optical glasses with excellent index homogeneities on large apertures of several 100 mm up to even meter sized lenses e.g. for atmospheric dispersion correction. The challenge of enabling highest refractive index homogeneities in small and large dimensions requires tight control of all production steps from melting to hot forming and fine annealing. This paper gives an insight overview on the process of generating high quality glass part from small glass pressings to meter sized glass blanks. It gives suitable help for the interpretation of refractive index homogeneity of optical glass in relation to their dimensions. Latest results added to this overview reflect the current state of this topic at the optical glass manufacturer SCHOTT.

Visible light optical coherence tomography (OCT) has recently emerged in retinal imaging, with claims of micrometer-scale axial resolution and multi-color (sub-band) imaging. Here, we show that the large dispersion of optical glass and aqueous media, together with broad optical bandwidths often used in visible light OCT, compromises both of these claims. To rectify this, we introduce the notion of spatially dependent (i.e., depth and transverse position-dependent) dispersion. We use a novel sub-band, sub-image correlation algorithm to estimate spatially dependent dispersion in our 109nm bandwidth visible light OCT mouse retinal imaging system centered at 587nm. After carefully compensating spatially dependent dispersion, we achieve delineation of fine outer retinal bands in mouse strains of varying pigmentation. Spatially dependent dispersion correction is critical for broader bandwidths and shorter visible wavelengths.

Glass is a ubiquitous material, which has proven to be fundamental also for the development of photonics and in particular of fiber and integrated optics. Figure 1 shows what is (at least at authors' knowledge) the first photo of the mode pattern of a planar waveguide, constituted by a liquid core in between two glass optical plates [1]. Even a few years before the appearance of the September 1969 issue of the Bell System Technical Journal which included seminal papers containing the word "integrated optics" in their title [2,3], planar optical waveguides had been demonstrated by using thermal tempering (namely, ion exchange) of an optical glass [4] and proton irradiation of fused silica |5|.

The opportunities and special features of using a multi-purpose digital holographic camera adapted for particle research for various diagnostic tasks, like plankton investigation in its habitat, optical glass diagnostics, and study of defects in single crystals, are investigated.

Thin films of 1-pentyl-2 / ,3 / -difluoro-3 /// -methyl-4 //// -octyl- p -quinquephenyl and 9,10-Bis (4-pentylphenylethynyl)antracene organic molecules were grown on optical glass, silicon and porous silicon substrates. First optical and luminescent properties of such hybrid composites are thoroughly studied using spectroscopic techniques. The strong decrease of aggregation in thin films of 1-pentyl-2 / ,3 / -difluoro-3 /// -methyl-4 //// -octyl- p -quinquephenyl on porous silicon was observed. The possibility of simultaneous red, green and blue tunable photon emission from organic film/porous silicon hybrid structure is demonstrated.

Glass exhibits excellent optical transmittance in the visible spectrum (400–700 nm). Therefore, it is widely used in optical systems such as laser projection and light delivering. In this study, an ultraviolet laser system was combined with a high-speed galvanometric scanner unit to mill optical glass materials. First, a numerical simulation approach was used to evaluate the effect of the bite distance of milling. After the laser milling of optical glass materials (sodalime and B270 glass), the surface morphology, surface roughness, and cross-section quality were analyzed using a three-dimensional confocal laser scanning microscope to evaluate the effects of milling parameters on optical glass materials.

In this work different fibre optic sensors for the structural health monitoring of civil engineering structures are reported. A fibre optic crack sensor and two different fibre optic moisture sensors have been designed to detect the moisture ingress in concrete based building structures. Moreover, the degeneration of the mechanical properties of optical glass fibre sensors and hence their long-term stability and reliability due to the mechanical and chemical impact of the concrete environment is discussed as well as the advantage of applying a fibre optic sensor system for the structural health monitoring of sewerage tunnels is demonstrated.

To improve surface planarity, a translational movement is added into the magnetorheoloigcal planarization process. To explore effects of some process parameters, including trajectory type, stroke and reciprocate velocity, on surface planarity, a set of finishing experiments are carried out. The results show that planarity is well improved when the trough reciprocates perpendicularly to the air gap. Surface planarity decreases as stoke increases but is hardly affected by reciprocate velocity. Using the magnetorheoloigcal planarization process with addition of translational movement, an ultra-smooth surface with planarity of micron order in PV is achieved on a K9 optical glass.

The processes changing the state of polished surfaces of BK10 optical silicate glass are examined and the effect of the ambient environment on them is determined. It is found that hexamethyldisilazane vapor treatment of the polished surfaces of optical components fabricated from this glass results in the formation of a hydrophobic film that protects them from high humidity.

Since thermal safety is a significant topic in Li-ion batteries (LIBs), monitoring the internal temperature can offer valuable information to clarify the mechanism of heat accumulation. However, it is a challenge to measure the internal temperature of LIBs due to the harsh electrochemical environment and unexpected impacts on the battery performance. For addressing such issue, a novel internal temperature measurement technique with a minimized influence on the electrochemical performance is developed for in situ measuring the internal temperature of the LIB. In the specific design, one end of the LIB is sealed with a BaF2 optical glass, through which the infrared camera is allowed for real-time monitoring the internal temperature during charging and discharging processes. In addition to a stable electrochemical performance in such the visualized LIB, the observation results indicate that the temperatures are different during the charging and discharging processes. A maximum temperature difference 2.0°C between internal and surface of the visualized LIB is observed at the end of discharge process under 2C rate condition. It indicates that internal temperature is more important to analyze the effects of temperature on the thermal safety of the high capacity LIBs. The proposed internal temperature measurement technique could be widely used for analyzing the effects of temperature on the thermal safety of LIBs in further work.

Every single day, a large amount of fish dies from infection such as hyperoxia-induced gas bubble disease consequences by unusual dissolved oxygen (DO) level due to the natural occurrences and human-caused processes of supersaturated water. We are concentrating on the issue of sustainability – an issue of great importance and where this interdisciplinary area has the potential to make a profound impact. We need to step up our game by introducing DO sensing and monitoring at a large scale to overcome this global environmental issue. DO is known as oxygen saturation, one of the most critical parameters in accessing water quality, and necessary to be kept at a sufficient level for the survival of many forms of aquatic biodiversity. Hence, this review article mainly focuses on the potential of optical glass micro-fibre transducers for DO sensing and monitoring, and its contribution toward water security impacts - as part of the Sustainable Goals Development blueprint. The growing body of literature associated with five main work packages i) research motivation of water security, ii) research market analysis discussing the perspective on size, share, growth, trends, and forecast, iii) typical approach on characterising DO level as compared to the optical glass micro-fibre based transducers, iv) conventional design of the optical glass micro-fibre based transducers and v) mechanism of light modulation characteristic in the optical glass micro-fibre based transducers, are highlighted in order to gain a better understanding on the development and progress of optical glass micro-fibre as a transducer for DO sensing and monitoring that can change our life for the better. Finally, several recommendations for future work are presented at the end of this study for the reference of future readers.

Large flat transmission mirrors made from optical glass BK7 are widely used in the high-power laser facility, which are required of stringent specifications for the whole spatial frequency errors. This work reveals the role of pad block’s support surface (PBSS) topography in measuring BK7 surface figure. Firstly, the PBSS topography was measured with laser displacement sensor. Secondly, the BK7 surface deformation at different pad blocks were simulated with finite element method and validated by experiments. Finally, a method was proposed to quantitively evaluate the different PBSS topography.

Optical glasses with certain inner quality e.g. low striae content are essential for good optical systems. A stria is a small local change in the refractive index inside the glass due to small local changes of the glass composition. A stria results in a wave front distortion that can cause a blurring of the image. The effect of striae inside optical glasses on different optical systems are simulated in order to value its significance. Such striae simulations turned out to be difficult and bringing the design software to its limits. Some pitfalls are discussed leading to criteria for trustworthy (reliable) simulation results. These criteria are shown and finally reliable simulation results for an eye piece used in a microscope are shown. Furthermore the results obtained in this publication lead to additional work on striae simulations.

More and more applications utilize the short wave infrared (SWIR) spectral range. The SWIR range is defined from about 0.9 to 3 μm. SWIR applications can be found for example in inspection processes of circuit boards, solar cells, bottles and food. The SWIR range is used in identification, sorting, surveillance, inspection and more. With SWIR applications characteristics can be visualized that normally would not be detectable with visible light, like rotten fruits in fruit sorting, fakes in paintings, content levels in visually non-transmitting bottles. For all these machine vision applications specific optics are used that in the ideal case have transmittance in the visual spectral range and in the SWIR range. Optical designs require materials that are transmittance in the visible and the SWIR range, sometimes even up to 4 μm. Most optical glasses have a good transmittance up to 2 μm, but at 2.5 μm the transmittance strongly decreases. There is also not much available information on the details of the transmittance curve in the SWIR range available of optical glass. This presentation will demonstrate SCHOTT optical glasses with good transmittance even up to 4 μm. If applications require transmittance at even larger wavelengths, it is possible to utilize IRG infrared material with transmittance up to 8 µm, that still can be used in the visible down to 0.6 μm. Other critical information for the optical designs are the dispersion and index change with temperature (dn/dT) characteristics in the SWIR range of these materials. This paper will discuss the availability of such data.

Concentration of sun light can be performed using different materials having the ability to either reflect or refract the light beams, from optical glass arrangements to legendary polished brass shields. More recently, advancements in the chemistry industry allowed development of synthetic films characterized by reflection indices close to those of historically applied glass mirrors. Said synthetic films however, typically having significant thin shapes, require supplementary substrate material capable of providing physical support and resistance to, necessarily, conserve a predefined shape which must be functional according to the specific practical application. Such supplementary materials normally granting to the synthetic reflecting film not just the necessary strength but also additional – and generally undesired – costs. Question rises whether it is possible to reduce impact on the global life cycle equation of the CPV installation by improving conversion efficiency and/or creating upsides that can reduce other operative costs. With those targets in mind, an alternative LCPV installation has been conceived where reflectors are designed to make productive use of the flexibility of synthetic mirror films, while PV cells are installed in receiver that includes automated cleaning plus cooling capabilities.

Optical applications in the 21st century are rapidly evolving, and materials with new capabilities are needed. Applications covering wide wavelength ranges are a particular challenge as materials can behave very differently in the ultraviolet, visible, and infrared spectral regions. A generalized model for selecting optical materials based on descriptions of dispersion and partial dispersion is presented. The relative behavior of various optical glasses is discussed based on glass composition. This is useful for both the optical designer and the glass maker as it illustrates the chemical origin of the dispersion curve and a possible path toward compositional tailoring of the optical properties to fit specific applications. This method can be extended from traditional optical glasses into the UV and infrared spectral ranges as it does not rely on predefined wavelengths at Fraunhofer lines.

A compound machine tool was designed, which combined rotary ultrasonic assisted grinding, electrical discharge machining (EDM) and multi-axis milling. Experimental results indicated that its positioning accuracy was less than 5.6 µm and its repetitive positioning accuracy was less than 1.8 µm; the vibration amplitude of ultrasonic grinding system was uniform and stable, and the EDM system worked well and stably. A smooth surface of K9 optical glass component was achieved by the grinding method.