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Photochromic glass darkens when exposed to light and reverts to transparency when the light is dim. It contains silver chloride that reacts reversibly to light. Such properties make photochromic glass suitable for use in optical lenses, car windshields, and smart energy efficient windows.
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Photochromatic lenses.rajkumar
Photochromatic lenses automatically darken when exposed to UV light and fade back to clear when removed from UV light. They contain silver halide crystals (in glass lenses) or spiroindoline molecules (in plastic lenses) that cause the darkening and fading reactions. Photochromatic lenses provide visual comfort both indoors and outdoors by automatically adjusting the amount of light transmitted based on UV exposure. While they have advantages like UV protection and automatic adjustment, they also have disadvantages like slower response time and reduced effectiveness in high heat. Proper dispensing requires understanding factors that impact performance like intensity, wavelength, temperature and exposure history.
Photochromic Lens
Photochromic lenses are lenses that darken when exposed to UV light such as sunlight and lighten when removed from the UV light source. They work by using small amounts of silver halide compounds like silver chloride, which darken when exposed to UV light. This darkening process occurs rapidly within a minute of UV exposure and lightening takes slightly longer at around 5-15 minutes without UV light. While Transitions lenses are a popular brand, many companies produce photochromic lenses with different technologies for achieving the lightening and darkening effect.
photochromatic lenses
Photochromic lenses darken when exposed to UV light such as sunlight and lighten when removed from the light source. They contain molecules like silver chloride that undergo a chemical reaction when exposed to UV rays, changing the lenses' transparency. Factors like light intensity, wavelength of incident radiation, temperature, and thickness impact how quickly the lenses darken and lighten. Photochromic lenses offer UV protection and visual comfort for people in varying light conditions.
Photochromic lenses explained
Photochromic lenses are lenses that darken when exposed to UV light and lighten when UV light is removed. They were originally made of glass with silver chemicals but now use organic molecules. Modern photochromic lenses can offer different levels of sun protection and transition speeds. While they provide adaptive sun protection, they have some disadvantages like not changing immediately and not working as well in cars. Drivewear lenses were developed for driving. Photochromic lenses can benefit children by protecting their eyes from UV exposure. Popular photochromic brands include Transitions and Reactolite, with Transitions being the fastest reacting. Eyekit.co offers Transitions Signature VII and Transitions XTRActive photochromic lenses.
Photochromic Lenses
Photochromic lenses change color in response to UV light. They darken when exposed to UV rays and lighten when UV exposure is removed. Various chemical compounds like silver chloride or naphthopyrans are used in glass or plastic lenses to enable this reversible color change. Photochromic lenses provide visual comfort both indoors and outdoors by automatically adjusting tint as needed.
Tinted lenses
This document discusses different types of tinted lenses, including their purposes and materials. It covers integral tints produced during manufacturing by adding metals or metal oxides to glass. Surface coatings deposit metallic oxides onto glass through evaporation. Plastic lenses are dyed by immersing them in organic dyes. Various tint colors like yellow, red, purple, and brown are explained in terms of the materials used and their applications. Integral tints provide consistent tinting while surface coatings and dyes allow tinting of any prescription.
Photochromatics.
This document provides an overview of photochromic lenses, including:
- A brief history of photochromic lenses from their introduction in 1964 to present day brands.
- An explanation of the chemical process behind how photochromic lenses darken and lighten in response to light.
- A comparison of glass and plastic photochromic lenses, and different manufacturing methods.
- Key factors that influence photochromic performance such as light intensity, temperature, and lens thickness.
- Advantages like UV protection and replacing clear and sunglasses, and disadvantages like delayed darkening.
- Tips for dispensing photochromic lenses and considerations for coatings and replacement.
Lens enhancement
The document discusses various lens enhancements that can be applied to spectacle lenses, including anti-reflection coatings, scratch-resistant coatings, UV coatings, and hydrophobic coatings. It provides details on the principles and techniques for applying anti-reflection coatings using single or multiple layers. Hard coatings and their scratch-resistant properties are also covered. Other topics include photochromic lenses that darken in sunlight, tinted lenses, polarizing lenses and their advantages in reducing glare.
Recommended
Photochromatic lenses.rajkumar
Photochromatic lenses automatically darken when exposed to UV light and fade back to clear when removed from UV light. They contain silver halide crystals (in glass lenses) or spiroindoline molecules (in plastic lenses) that cause the darkening and fading reactions. Photochromatic lenses provide visual comfort both indoors and outdoors by automatically adjusting the amount of light transmitted based on UV exposure. While they have advantages like UV protection and automatic adjustment, they also have disadvantages like slower response time and reduced effectiveness in high heat. Proper dispensing requires understanding factors that impact performance like intensity, wavelength, temperature and exposure history.
Photochromic Lens
Photochromic lenses are lenses that darken when exposed to UV light such as sunlight and lighten when removed from the UV light source. They work by using small amounts of silver halide compounds like silver chloride, which darken when exposed to UV light. This darkening process occurs rapidly within a minute of UV exposure and lightening takes slightly longer at around 5-15 minutes without UV light. While Transitions lenses are a popular brand, many companies produce photochromic lenses with different technologies for achieving the lightening and darkening effect.
photochromatic lenses
Photochromic lenses darken when exposed to UV light such as sunlight and lighten when removed from the light source. They contain molecules like silver chloride that undergo a chemical reaction when exposed to UV rays, changing the lenses' transparency. Factors like light intensity, wavelength of incident radiation, temperature, and thickness impact how quickly the lenses darken and lighten. Photochromic lenses offer UV protection and visual comfort for people in varying light conditions.
Photochromic lenses explained
Photochromic lenses are lenses that darken when exposed to UV light and lighten when UV light is removed. They were originally made of glass with silver chemicals but now use organic molecules. Modern photochromic lenses can offer different levels of sun protection and transition speeds. While they provide adaptive sun protection, they have some disadvantages like not changing immediately and not working as well in cars. Drivewear lenses were developed for driving. Photochromic lenses can benefit children by protecting their eyes from UV exposure. Popular photochromic brands include Transitions and Reactolite, with Transitions being the fastest reacting. Eyekit.co offers Transitions Signature VII and Transitions XTRActive photochromic lenses.
Photochromic Lenses
Photochromic lenses change color in response to UV light. They darken when exposed to UV rays and lighten when UV exposure is removed. Various chemical compounds like silver chloride or naphthopyrans are used in glass or plastic lenses to enable this reversible color change. Photochromic lenses provide visual comfort both indoors and outdoors by automatically adjusting tint as needed.
Tinted lenses
This document discusses different types of tinted lenses, including their purposes and materials. It covers integral tints produced during manufacturing by adding metals or metal oxides to glass. Surface coatings deposit metallic oxides onto glass through evaporation. Plastic lenses are dyed by immersing them in organic dyes. Various tint colors like yellow, red, purple, and brown are explained in terms of the materials used and their applications. Integral tints provide consistent tinting while surface coatings and dyes allow tinting of any prescription.
Photochromatics.
This document provides an overview of photochromic lenses, including:
- A brief history of photochromic lenses from their introduction in 1964 to present day brands.
- An explanation of the chemical process behind how photochromic lenses darken and lighten in response to light.
- A comparison of glass and plastic photochromic lenses, and different manufacturing methods.
- Key factors that influence photochromic performance such as light intensity, temperature, and lens thickness.
- Advantages like UV protection and replacing clear and sunglasses, and disadvantages like delayed darkening.
- Tips for dispensing photochromic lenses and considerations for coatings and replacement.
Lens enhancement
The document discusses various lens enhancements that can be applied to spectacle lenses, including anti-reflection coatings, scratch-resistant coatings, UV coatings, and hydrophobic coatings. It provides details on the principles and techniques for applying anti-reflection coatings using single or multiple layers. Hard coatings and their scratch-resistant properties are also covered. Other topics include photochromic lenses that darken in sunlight, tinted lenses, polarizing lenses and their advantages in reducing glare.
Polarized lenses
Polarizing lenses reduce glare caused by reflections from surfaces like water, snow, and highways. They work by blocking horizontally polarized light that is reflected from these surfaces, while transmitting regular light. The lenses contain a special filter made of polyvinyl acetate and iodine that absorbs the horizontally vibrating components of light. Polarizing lenses can be made for prescription lenses by mounting the polarizing filter between layers of hard resin or polycarbonate. They provide benefits like reduced driving fatigue and improved visibility for activities like fishing or at the beach.
Polaroid lenses
Polarized lenses block certain types of light waves to reduce glare. They work by only allowing vertically polarized light to enter the eye, blocking out horizontally polarized light that causes glare when reflected off smooth surfaces like water or roads. Polarized lenses come in various colors and are useful for activities like driving, boating, and photography by improving contrast and reducing eye strain from glare. While effective at reducing most types of glare, polarized lenses have some limitations like not working as well with snow glare and possibly distorting displays.
anti glare lenses & their applictions
This document discusses anti-glare and anti-reflective coatings that can be applied to eyeglass lenses. It explains that these coatings reduce glare and reflections by 8% or more, improving vision and reducing eye strain. The coatings work by using thin transparent films with refractive indexes that change the wavelength and angle of incoming light. Common coating materials include magnesium fluoride and fluoropolymers. Anti-glare coatings provide benefits like improved contrast, easier cleaning, and protection from eye fatigue during computer use.
Absorptive lenses
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Photochromatic lenses and tints www.eyenirvaan.com
This document discusses photochromatic lenses and lens tints. It describes how photochromics work using either glass or plastic and different manufacturing methods like imbibition and in-mass. Glass photochromics darken fully but don't lighten indoors while plastic may fade over time. Factors like temperature, UV exposure and lens thickness affect performance. Tints are made through coatings using metallic oxides or dyeing plastics, with different colors absorbing distinct light wavelengths to provide benefits like reducing glare or improving contrast.
lens coatings
Hard coating provides the best scratch resistance for glass and is the most durable ingredient for anti-reflection coating. The two most common types of hard coating are thermally cured dip hard coating, where the lens passes through a liquid bath to adhere the coating to both sides, and UV cured hard coating, where a liquid solution is applied and then cured under UV light. Smudge resistant coating protects glasses from smudges like oil and dirt to improve durability. Anti-fog coating prevents the condensation of water droplets on the lens surface that causes fogging, working by applying a surfactant film or creating a hydrophilic surface. Crizal Prevencia glasses provide glare, smudge, scratch, UV, and
Photochromatic lenses
1) Photochromic lenses are lenses that darken when exposed to UV light and fade back to clear when removed from the light. They help the eyes adapt to changing light conditions both indoors and outdoors.
2) There are two main types of photochromic lenses - glass and plastic. Glass uses silver halide crystals while plastic uses spiroxazine molecules. Both darken when activated by UV rays and fade when the UV exposure is removed.
3) Factors like temperature, thickness, intensity of UV light, and exposure history affect how quickly and darkly the lenses change color. Photochromic lenses provide eye comfort in varying light but have some limitations like delayed response time and gradual loss of darkening ability over
Absorptive lens, transmission standards
1. Light interacts with lenses through reflection, absorption, and transmission. The percentage transmitted determines a lens's clarity.
2. Absorption follows Lambert's law - layers of equal thickness absorb equal percentages of light. Transmittance and opacity can be calculated by multiplying transmission/absorption of individual lenses.
3. The ocular media (tear, cornea, lens, vitreous) absorb different wavelengths of light to varying degrees depending on age, transmitting light that stimulates vision or causes harm through thermal or photochemical effects. Sunglasses reduce these effects by filtering radiation.
Oph. lens material, tint,coating
Ophthalmic lens materials can be natural, glass, or plastic. Natural materials like quartz are no longer used. Glass is made of sand, soda, lime, and other ingredients. It has good optical clarity but is heavy. Plastics like CR-39 and polycarbonate are lighter alternatives to glass. New materials like Trivex and high index plastics allow for thinner lenses. Each material has unique optical, mechanical, electrical, chemical, and thermal properties that make it suitable for different applications in ophthalmic lenses.
Polarized sunglasses
- Edwin Land invented polarizing film and demonstrated its use in sunglasses by using polarized filters to view fish in a tank that were obscured by sunlight glare.
- The first polarized sunglasses used polarized sheet film laminated between glass, which caused delamination problems. Plastic polarized lenses were later developed.
- Modern polarized plastic lenses are produced using a process where the polarizing film is suspended in the mold during the plastic injection molding process.
Coatings applied to spectacle lenses
This document discusses various lens coatings and their properties. It covers coatings that provide protection from UV rays and scratches, as well as coatings that reduce glare, fogging, and ghost images. Specific coatings mentioned include MAR coating, tints, UV coating, scratch resistant coating, polarized coating, and edge coatings. The document also discusses the purpose and processes of lens tinting, as well as the uses and limitations of polarized lenses.
Photochromatic lenses
This document provides an overview of photochromatic lenses, including:
1. It discusses the working mechanism of photochromatic lenses, which use silver halide compounds that change color when exposed to UV light through a reversible photolytic reaction.
2. It describes the different types of photochromatic lenses, including glass, plastic, and variations like PhotoGray, PhotoSun, and thin and dark lenses.
3. The document outlines factors that influence photochromatic performance such as crystal size, temperature, and UV wavelength exposure.
Lens enhancement considering for prescribing
This document discusses various lens enhancements that can be applied to prescription lenses, including anti-reflection coatings, scratch-resistant coatings, and hydrophobic coatings. It provides details on how each type of coating works and is applied. Anti-reflection coatings reduce unwanted reflections using destructive interference of light waves. They are applied in very thin layers, with precise thickness needed. Scratch-resistant coatings increase the hardness and durability of plastic lenses through additional layers. Hydrophobic coatings create a high contact angle to allow water and oils to bead up and roll off the lens surface.
Lens surface coating
This document provides information on various lens surface coatings and their types and purposes. It discusses why coatings are applied, including for protection, appearance, clarity and to prevent fogging. It then describes common coating types like MAR coating, tints, scratch resistant coating, mirror coating, polarized coating and edge coatings. It goes on to explain uncoated lenses, single side coated lenses, hard coatings, hydrophobic/oleophobic coatings, anti-reflection coatings, scratch resistance coatings, clean coats, drive safe coats and coatings that provide protection from blue light. The document provides details on how each of these coating types work and their benefits.
Difference between filters and tints
Filters allow useful light to enter the eye while filtering out disturbing light, maintaining vision. Tints do not discriminate between light waves and can reduce vision by blocking both useful and disturbing light. Filters come in various colors for specific diagnostic purposes like enhancing blood vessel visibility, while tints are not used diagnostically. Therapeutically, filters are used to control light sensitivity and enhance contrast for various eye conditions, while tints only help reduce glare in cataracts and albinism without enhancing contrast. Filters are available only in plastic while tints come in both plastic and glass.
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This document discusses different types of magnification and illumination used in microscopy. It describes the components that provide magnification, including the eyepiece and objectives, and how their magnification values are multiplied to calculate total magnification. It also explains three main illumination techniques: critical illumination, Kohler illumination, and dark field illumination. Critical illumination focuses light in the same plane as the specimen. Kohler illumination focuses an image of the light source in the condenser plane. Dark field illumination uses oblique light to view unstained specimens as bright objects on a dark background.
High index
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Absorptive lens, transmission and sunglass standards (explained)
1. Light transmission through lenses is determined by calculating the percentage of light lost to reflection off the front and back surfaces and light absorbed by the lens material.
2. The human eye absorbs different wavelengths of light depending on the ocular tissue. The cornea absorbs UV light while the lens absorbs more UV as we age.
3. Sunglasses protect the eyes by reducing the amount of UV and infrared radiation that reaches the eyes, preventing damage from prolonged sun exposure like cataracts.
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Polarizing lenses reduce glare caused by reflections from surfaces like water, snow, and highways. They work by blocking horizontally polarized light that is reflected from these surfaces, while transmitting regular light. The lenses contain a special filter made of polyvinyl acetate and iodine that absorbs the horizontally vibrating components of light. Polarizing lenses can be made for prescription lenses by mounting the polarizing filter between layers of hard resin or polycarbonate. They provide benefits like reduced driving fatigue and improved visibility for activities like fishing or at the beach.
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Polarized lenses block certain types of light waves to reduce glare. They work by only allowing vertically polarized light to enter the eye, blocking out horizontally polarized light that causes glare when reflected off smooth surfaces like water or roads. Polarized lenses come in various colors and are useful for activities like driving, boating, and photography by improving contrast and reducing eye strain from glare. While effective at reducing most types of glare, polarized lenses have some limitations like not working as well with snow glare and possibly distorting displays.
anti glare lenses & their applictions
This document discusses anti-glare and anti-reflective coatings that can be applied to eyeglass lenses. It explains that these coatings reduce glare and reflections by 8% or more, improving vision and reducing eye strain. The coatings work by using thin transparent films with refractive indexes that change the wavelength and angle of incoming light. Common coating materials include magnesium fluoride and fluoropolymers. Anti-glare coatings provide benefits like improved contrast, easier cleaning, and protection from eye fatigue during computer use.
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This document discusses photochromatic lenses and lens tints. It describes how photochromics work using either glass or plastic and different manufacturing methods like imbibition and in-mass. Glass photochromics darken fully but don't lighten indoors while plastic may fade over time. Factors like temperature, UV exposure and lens thickness affect performance. Tints are made through coatings using metallic oxides or dyeing plastics, with different colors absorbing distinct light wavelengths to provide benefits like reducing glare or improving contrast.
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Photochromatic lenses
1) Photochromic lenses are lenses that darken when exposed to UV light and fade back to clear when removed from the light. They help the eyes adapt to changing light conditions both indoors and outdoors.
2) There are two main types of photochromic lenses - glass and plastic. Glass uses silver halide crystals while plastic uses spiroxazine molecules. Both darken when activated by UV rays and fade when the UV exposure is removed.
3) Factors like temperature, thickness, intensity of UV light, and exposure history affect how quickly and darkly the lenses change color. Photochromic lenses provide eye comfort in varying light but have some limitations like delayed response time and gradual loss of darkening ability over
Absorptive lens, transmission standards
1. Light interacts with lenses through reflection, absorption, and transmission. The percentage transmitted determines a lens's clarity.
2. Absorption follows Lambert's law - layers of equal thickness absorb equal percentages of light. Transmittance and opacity can be calculated by multiplying transmission/absorption of individual lenses.
3. The ocular media (tear, cornea, lens, vitreous) absorb different wavelengths of light to varying degrees depending on age, transmitting light that stimulates vision or causes harm through thermal or photochemical effects. Sunglasses reduce these effects by filtering radiation.
Oph. lens material, tint,coating
Ophthalmic lens materials can be natural, glass, or plastic. Natural materials like quartz are no longer used. Glass is made of sand, soda, lime, and other ingredients. It has good optical clarity but is heavy. Plastics like CR-39 and polycarbonate are lighter alternatives to glass. New materials like Trivex and high index plastics allow for thinner lenses. Each material has unique optical, mechanical, electrical, chemical, and thermal properties that make it suitable for different applications in ophthalmic lenses.
Polarized sunglasses
- Edwin Land invented polarizing film and demonstrated its use in sunglasses by using polarized filters to view fish in a tank that were obscured by sunlight glare.
- The first polarized sunglasses used polarized sheet film laminated between glass, which caused delamination problems. Plastic polarized lenses were later developed.
- Modern polarized plastic lenses are produced using a process where the polarizing film is suspended in the mold during the plastic injection molding process.
Coatings applied to spectacle lenses
This document discusses various lens coatings and their properties. It covers coatings that provide protection from UV rays and scratches, as well as coatings that reduce glare, fogging, and ghost images. Specific coatings mentioned include MAR coating, tints, UV coating, scratch resistant coating, polarized coating, and edge coatings. The document also discusses the purpose and processes of lens tinting, as well as the uses and limitations of polarized lenses.
Photochromatic lenses
This document provides an overview of photochromatic lenses, including:
1. It discusses the working mechanism of photochromatic lenses, which use silver halide compounds that change color when exposed to UV light through a reversible photolytic reaction.
2. It describes the different types of photochromatic lenses, including glass, plastic, and variations like PhotoGray, PhotoSun, and thin and dark lenses.
3. The document outlines factors that influence photochromatic performance such as crystal size, temperature, and UV wavelength exposure.
Lens enhancement considering for prescribing
This document discusses various lens enhancements that can be applied to prescription lenses, including anti-reflection coatings, scratch-resistant coatings, and hydrophobic coatings. It provides details on how each type of coating works and is applied. Anti-reflection coatings reduce unwanted reflections using destructive interference of light waves. They are applied in very thin layers, with precise thickness needed. Scratch-resistant coatings increase the hardness and durability of plastic lenses through additional layers. Hydrophobic coatings create a high contact angle to allow water and oils to bead up and roll off the lens surface.
Lens surface coating
This document provides information on various lens surface coatings and their types and purposes. It discusses why coatings are applied, including for protection, appearance, clarity and to prevent fogging. It then describes common coating types like MAR coating, tints, scratch resistant coating, mirror coating, polarized coating and edge coatings. It goes on to explain uncoated lenses, single side coated lenses, hard coatings, hydrophobic/oleophobic coatings, anti-reflection coatings, scratch resistance coatings, clean coats, drive safe coats and coatings that provide protection from blue light. The document provides details on how each of these coating types work and their benefits.
Difference between filters and tints
Filters allow useful light to enter the eye while filtering out disturbing light, maintaining vision. Tints do not discriminate between light waves and can reduce vision by blocking both useful and disturbing light. Filters come in various colors for specific diagnostic purposes like enhancing blood vessel visibility, while tints are not used diagnostically. Therapeutically, filters are used to control light sensitivity and enhance contrast for various eye conditions, while tints only help reduce glare in cataracts and albinism without enhancing contrast. Filters are available only in plastic while tints come in both plastic and glass.
DARK FIELD MICROSCOPY
Slides includes all details about Dark field Microscopy.
useful for MTech, pharmacy student which dealing with microbiology. also for reference to study Dark Field Microscopy. includes principle, instrumentation, working, uses etc.
Radiographic film
X-ray film was originally recorded on glass plates but nitrocellulose film replaced them during WWI due to its greater feasibility. Double emulsion film was later found to respond faster to x-rays. By 1924, cellulose acetate replaced the flammable nitrocellulose film. Radiographic film consists of a polyester base and emulsion layers containing gelatin and light-sensitive silver halide crystals. Exposure to x-rays or light from intensifying screens causes a latent image in the crystals that is developed to produce the final image. Factors like contrast, speed, and spectral matching must be considered when selecting a film.
magnification and illumination of microscopes
This document discusses different types of magnification and illumination used in microscopy. It describes the components that provide magnification, including the eyepiece and objectives, and how their magnification values are multiplied to calculate total magnification. It also explains three main illumination techniques: critical illumination, Kohler illumination, and dark field illumination. Critical illumination focuses light in the same plane as the specimen. Kohler illumination focuses an image of the light source in the condenser plane. Dark field illumination uses oblique light to view unstained specimens as bright objects on a dark background.
High index
The refractive index is the ratio of the speed of light in a vacuum to the speed of light in a material. Materials with a higher refractive index bend light more and allow for thinner lenses. High index lenses have a refractive index greater than 1.49 for plastics and 1.523 for glass. They provide benefits like thinner and lighter lenses but also have disadvantages like increased chromatic aberration. Common materials used include lanthanum, titanium, and polyurethane.
Absorptive lens, transmission and sunglass standards (explained)
1. Light transmission through lenses is determined by calculating the percentage of light lost to reflection off the front and back surfaces and light absorbed by the lens material.
2. The human eye absorbs different wavelengths of light depending on the ocular tissue. The cornea absorbs UV light while the lens absorbs more UV as we age.
3. Sunglasses protect the eyes by reducing the amount of UV and infrared radiation that reaches the eyes, preventing damage from prolonged sun exposure like cataracts.
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Photochromatic lenses and tints www.eyenirvaan.com
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Absorptive lens, transmission and sunglass standards (explained)
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Project Glass is a Google research program developing augmented reality glasses. The glasses would allow hands-free access to smartphone information through voice commands and a small video display visible through the lens. Key features would include notifications, maps, photos/videos. The glasses use technologies like wearable computing, ambient intelligence, Android, and augmented reality. Advantages are easy access to information, but disadvantages include privacy concerns and potential for distraction. The future of Project Glass could include improved designs as the technology becomes more integrated into daily life.
Sound insulation materials
This document provides information on various sound insulation materials, including their characteristics, pricing, sizes, and intended uses. Glass mineral wool is made from recycled glass, limestone and soda ash to form fine strands that are bound together. It has good tear strength and is lightweight with low environmental impact. Rock mineral wool is made from volcanic rock and recycled slag, and has high compressive strength. It can be used for thermal insulation and fire protection. Foamed plastics like extruded polystyrene are made through an extrusion process and have high compressive strength, water resistance and freeze-thaw performance. Products like Quiet Batt and Studio Pro are high-performance sound absorbing insulation materials used residentially and commercially.
Different types of glasses
There are 12 main types of glasses used in construction including laminated glass, toughened glass, fusion glass, mirrors, etched glass, float glass, stained glass, beveled glass, figured glass, cast glass, frameless doors, and tinted glass. Each type has distinct properties like safety qualities, strength, clarity, coloration, or artistic effects. Laminated glass uses an interlayer to stay intact rather than shatter into sharp pieces when broken. Toughened glass similarly breaks into small cubes rather than shards.
Glass
Glass is produced by heating silica, lime, and soda or potash to over 10000C. Other ingredients like iron oxide and lead oxide are added to modify properties. Glass consists mainly of silica which is made fusible by alkaline mixtures. Potash makes glass infusible while soda accelerates fusion. Lime provides durability and toughness. Lead oxide adds color. Glass is classified as soda lime, lead, or boro-silicate based on composition. Special forms include sheet, plate, colored, wired, structural, laminated, bulletproof, fiber, foam, and flint glass. Glass has properties like shine, stability, insulation, and transparency and is used widely in construction, decoration, insulation,
SMART Materials
Introduction to Smart Materials, Classification of Smart Materials, Different types of Smart Materials and their applications.
Smart materials.. smart ppt
This document provides an overview of smart materials, including their properties, components of smart systems, classifications, examples like shape memory alloys and quantum tunnelling composites, applications, and merits and demerits. Smart materials are materials that can respond and adapt to environmental changes through stimuli like temperature, pressure, electricity, light or mechanics. They are classified into groups like piezoelectric, thermoresponsive and electrochromic materials. Shape memory alloys can return to their original shape when heated after deformation while quantum tunnelling composites change from an insulator to a conductor under pressure. Potential applications include aircraft, orthopedics, robotics and smart glass.
Glass
Glass is an amorphous solid made by cooling molten ingredients without crystallization. It is typically made from mixtures of silicates, borates, and aluminates. Glass can be transparent, translucent, or opaque depending on its composition. Common types of glass include soda-lime glass for windows, borosilicate glass for laboratory equipment, and lead glass for radiation shielding. Glass has many uses including windows, tableware, light bulbs, and optical lenses due to its optical properties and resistance to corrosion.
UNDER WATER ACOUSTIC COMMUNICATION
Underwater acoustic communication uses sound waves to transmit data underwater instead of electromagnetic waves. It allows remote control of underwater instruments and real-time data transmission. Examples include acoustic modems that convert digital data to sound signals, the Deep-ocean Assessment and Reporting of Tsunamis program's acoustic sensors that detect tsunamis, and robotic crawlers equipped with cameras and modems that can locate underwater objects and transmit images.
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Smart Glasses Market report 2015: towards 1 billion shipments
Smart Glasses Market report 2015: towards 1 billion shipments
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Information about Photochromatic Spectacle Lens.pptx
Photochromic lenses, also known as transition lenses, darken when exposed to UV light and lighten when removed from UV light. They contain materials like silver halides in glass lenses and spiro-indoline molecules in plastic lenses that cause a reversible chemical reaction when exposed to UV light, changing the lens from clear to dark. While providing UV protection and convenience of changing tint, they have disadvantages like slower reaction times in cold weather and vehicles as well as higher cost compared to regular lenses.
Spectacles
This document discusses various types of lenses and coatings used in eyeglasses. It describes unifocal lenses that provide single vision correction and multifocal lenses like bifocals and trifocals that correct for both distance and near vision. Progressive lenses provide a seamless transition between vision corrections. Hi-index and lightweight lenses reduce thickness. Photochromic lenses darken in sunlight and clear in low light. Polarized and tinted lenses reduce glare. Polycarbonate lenses are impact resistant. Anti-reflective coatings improve vision clarity and comfort.
eLens coatings explained
There are several coatings that can be applied to lenses to improve vision and performance. Scratch-resistant coatings protect the surface of plastic and polycarbonate lenses. Anti-reflective coatings reduce glare by decreasing the reflection of light off the lens surface. Anti-fog coatings prevent moisture from forming on the inside of lenses. UV coatings provide protection from ultraviolet rays without significantly darkening the lens. Mirror coatings reflect light away from the eyes to reduce brightness. Tints can be added to lenses in various colors and shades.
Sunglass by alamin
Sunglasses have existed since prehistoric times and were originally used to reduce glare and provide comfortable vision in bright light. Over time, sunglasses evolved to include specific lens materials and coatings to block UV rays and reduce glare. Today, sunglasses are manufactured using various plastic and metal materials for frames and lenses. Lenses are produced through processes like dying plastics or incorporating metallic oxides while they are molten. Frames are constructed to securely hold lenses using tension or screw mounts. Regulations require sunglasses to achieve certain standards for UV protection. Popular brands mass produce high quality sunglasses with advanced lens technologies to protect vision and health.
Photochromatic lenses
1) Photochromic lenses are lenses that darken when exposed to UV light and fade back to clear when removed from the light. They help the eyes adapt to changing light conditions both indoors and outdoors.
2) There are two main types of photochromic lenses - glass and plastic. Glass uses silver halide crystals while plastic uses spiroxazine molecules that change conformation with UV exposure.
3) Factors like UV intensity, temperature, and lens thickness affect how quickly and darkly the lenses change color. Thinner lenses with higher UV exposure at warmer temperatures will darken faster.
Stanton Optical Roseville 2014
Stanton Optical Roseville offers eyecare and vision care services including eye exams, eyeglasses and more. Conveniently located in Roseville, California, Stanton Optical strives for complete satisfaction.
Stanton Optical Sacramento 2014
Lenses have come a long way from traditional bifocals, and it's always great to keep yourself informed about the new technology. This is some information all about transition lenses, and the science behind them. If you're considering getting transitions lenses, take a look!
spectacles.pptx
Spectacles consist of lenses held in a frame that extends towards the ears. The frame holds the lenses and comes in various materials like plastic, metal, and nylon. Lenses can be made of glass or plastics like CR-39, polycarbonate and Trivex. Lens forms include flat lenses, curved lenses like meniscus and toric lenses. Spectacles can be single vision, bifocal, trifocal or progressive. Additional lens features include coatings like anti-reflective, scratch-resistant, UV and photochromic coatings.
Transitions vantage lenses explained
Transitions Vantage lenses incorporate photochromic lenses that darken in sunlight plus added variable polarization. As the lenses darken outdoors, vision becomes crisper with reduced glare. Color contrast and perception are also richer and more vivid. Transitions Vantage lenses are the first to darken and polarize outdoors while being clear indoors. They block glare from surfaces like roads and water by filtering light and providing better clarity, especially in everyday situations. The lenses increase polarization as they darken outdoors to improve sharpness under tree shadows or in bright city streets.
Types of spectacle lenses
discussed about types of lenses , lens materials, advantages, newly updated brands,guides for choosing perfect lenses with pictures.
WK2-MIRROR-FINAL.pptx
This document discusses the qualitative characteristics of images formed by plane and curved mirrors and lenses. It begins by stating the objectives of predicting the orientation, type, and magnification of images formed, and explaining the uses of lenses and mirrors. It then provides information on the reflection of light in plane and curved mirrors, including definitions, laws of reflection, and the characteristics of images formed. It also discusses the two types of spherical mirrors - concave and convex - and their uses. Finally, it outlines the uses of convex and concave lenses, including in microscopes, cameras, correcting vision, and as the natural lenses in human eyes.
Lighting Technology Review
This document compares different lighting technologies for lighting towers. Metal halide lighting is becoming outdated due to high maintenance costs from frequent bulb changes and fuel consumption. LEDs have improved but produce intense blue glare and have lower color rendering. CDM (cold cathode discharge metal) provides the best quality light with high color rendering and efficiency, directly replacing 1000W metal halide with only 150W while reducing glare. CDM produces "mesopic light" that stimulates both rod and cone cells in the eye for better visibility compared to the photopic light of other technologies. It has additional advantages including longer life, lower costs, and reducing health and safety risks from glare, flicker, and light pollution.
Glare from eyeglass lenses
8% of light that hits eyeglass lenses causes annoying reflections and glare, disturbing vision and reducing clarity. Special coatings can now virtually eliminate all reflections and glare, which is important for reducing computer vision syndrome. These anti-reflective or anti-reflection coatings are thin transparent films that change the wavelength and angle of incoming light. They were invented in the 1930s but improved since. By reducing stray light, they improve contrast and vision while also making eye contact and appearance of glasses better.
Sodlcmirror
SODLC Mirror is a company founded in 2009 that provides high-quality bathroom mirrors, including intelligent bathroom mirrors, LED lighted mirrors, medicine cabinets, infinity mirrors, and salon mirrors. They have a professional production team and technical staff that allows them to offer a wide range of mirror styles. Their mirrors are designed to match various residential, hospitality, and commercial spaces.
Eye as an optical system.
This slide share presentation will help you to know the comparison of our natural eye with artificial optical system (Camera).
Absorptive lenses
How to protect your eye?
With sunglasses? Mirror glasses? Tinted or polarized glasses?
What is right tint colour for you?
What are antireflection coat glasses?
Спортивные, солнцезащитные очки (catalog).
Eyewear catalog
GLOBAL VISION EYEWEAR CORPORATION USA.
Украина, Киев, nrcgvua@gmail.com
Solar Glass Dictionery Qingdao Cngrow
The document defines and describes various types of solar glass:
1) Low iron patterned glass is ultra-clear rolled glass mainly used as sealing glass for solar cells. It has high sunlight transmittance and low iron content.
2) Low iron float glass, also called ultra-clear float glass, has high transmittance and is used as cover or base glass for thin film PV panels.
3) AR coating can be applied to low iron patterned or float glass to reduce reflectance and improve transmittance, raising PV module efficiency.
4) TCO glass is float glass coated with a transparent conductive oxide film and used for thin film solar cells.
5) Back
Quarter 2 – Module 4.pptx
This document discusses the uses of mirrors and lenses. It describes how mirrors are used in vehicles to allow drivers to see behind them, and how curved mirrors produce multiple images. Lenses are also discussed, noting how they allow observation of microorganisms and distant objects. Specific uses of convex lenses are outlined, including in microscopes, cameras, magnifying glasses, eyeglasses, and the human eye. Concave lenses are then described and their uses in binoculars, telescopes, eyeglasses for nearsightedness, and peepholes.
Optical/ Metallurgical Microscopy
Optical lenses are used in microscopes to form magnified images of microscopic objects. A lens has curved surfaces that focus light rays to form these images. Single lenses are used in eyeglasses and cameras, while compound lenses with multiple elements are used in microscopes and telescopes to correct optical aberrations. A metallurgical microscope uses reflected light to illuminate and image opaque metal samples, allowing metallurgists to examine microstructural details at magnifications from 1 to 1500x. Objectives resolve microstructural details while eyepieces further magnify the image without additional resolution.
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Information about Photochromatic Spectacle Lens.pptx
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EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
Orion Air Quality Monitoring Systems - CWS
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptx
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Deep Software Variability and Frictionless Reproducibility
Deep Software Variability and Frictionless ReproducibilityUniversity of Rennes, INSA Rennes, Inria/IRISA, CNRS
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
The binding of cosmological structures by massless topological defects
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
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Nucleophilic Addition of carbonyl compounds.pptx
Nucleophilic addition is the most important reaction of carbonyls. Not just aldehydes and ketones, but also carboxylic acid derivatives in general.
Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
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Unveiling the Energy Potential of Marshmallow Deposits: A Revolutionary
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Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...
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Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
BREEDING METHODS FOR DISEASE RESISTANCE.pptx
Plant breeding for disease resistance is a strategy to reduce crop losses caused by disease. Plants have an innate immune system that allows them to recognize pathogens and provide resistance. However, breeding for long-lasting resistance often involves combining multiple resistance genes
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Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
ESR spectroscopy in liquid food and beverages.pptx
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
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Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
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EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
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Deep Software Variability and Frictionless Reproducibility
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The binding of cosmological structures by massless topological defects
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Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...
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ESR spectroscopy in liquid food and beverages.pptx
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Nucleic Acid-its structural and functional complexity.
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Chemistry presentation
- 2. Photochromic materials are those which react reversibly to light.
- 3. Smart energy efficient window
- 4. Optical lens
- 5. Script: Next, let us discuss about photochromic glasses. Photochromic materials are those which react reversibly to light. It contains of silver chloride which is sensitive to light. When it is exposed to light, silver chloride is converted into silver and the glass darkens. The photochromic glass will revert to transparency once the light is dim. These properties make it a perfect material in manufacturing optical lens, car windshields and also smart energy efficient window. Here, I would like to make a full detail in optical lens. Nowadays, optical lenses are very common as it is really efficient in blocking the UV light. The lenses are clear in indoor or at night but it will automatically darken when it is exposed to the sunlight.