Variable focus microlens history book

A typical microlens may be a single element with one plane surface and one spherical convex. Oct 29, 2002 design and fabrication of an xray lens assembly for focusing xray beams is described. The microlens is made of two immiscible liquids and a soft polymer, polydimethylsiloxane pdms. The na is chosen as a metric of the lenses as well as the range of focal lengths since it gives an idea of how much. A microlens is a small lens, generally with a diameter less than a millimetre mm and often as. Variable focus moire lenses composed of diffractive optical elements does utilize moire patterns, making them ideal for a range of applications. A microlens is a small lens, generally with a diameter less than a millimetre mm and often as small as 10 micrometres m. View daily, weekly or monthly format back to when micro focus international plc o stock was issued.

Language reference micro focus cobol paperback january 1, 1994 by micro focus author. In thermal reflow processes, microlenses are made by heating pr cylinders. Mar 25, 2020 focus stacking is a technique that allows you to combine multiple photographs with different focus distances to produce a single image with more of a subject in focus. A variable focus liquid lens using a transparent flat cell is demonstrated. Lytro began shipping its first generation pocketsized camera, capable of refocusing images after being taken, in 8 gb and 16 gb versions on february 29, 2012. Abstract this video introduces a novel variable focus lens with a large optical aperture of 26 mm. When utilized in edgelit architectures for ledbased fixtures and lamps, microlens optics provide a costeffective, highefficiency solution for unmatched design possibilities. By applying a pressure to the outer membrane inward causes the liquid to redistribute and swell the inner membrane outward which, in turn. Micro focus cobol workbench for the application developer 1st edition by peter molchan author, jr. The companys goal and charter was to design and engrave optical patterns into cylinders that could be used to produce lenticular plastic sheets.

In a lens cell, two immiscible dielectric liquids but with different dielectric constants are sandwiched between electrodes. Variable focus liquid lens by changing aperture hongwen ren and shintson wu 2005 applied physics letters 86 211107. These tunable microlenses provide adaptive focusing with adjustable curved. The lens profile is assumed to be a spherical shape in this equation. They compensate for refractive errors such as presbyopia by providing variable focusing, allowing users to adjust them for desired distance or prescription, or both current bifocals and progressive lenses are static, in that the user has to change their eye position to look through the portion of the lens with the. In each case, a transverse electric field is used to create an electrostatic pressure, giving rise to the transport of. However, screens today are much larger and are often situated much further away from the user.

A variablefocus liquidfilled optical lens consists of a solid plate, a ring. Adjustable focus eyeglasses are eyeglasses with an adjustable focal length. Pdms membrane microactuator for focal tunable microlens seok woo lee. Properties, fabrication and liquid lenses examines the recent progress in the emerging field of liquidbased microlenses. Calculation of dep and ewod forces for application in. Cormack1 1department of electrical, computer, and energy engineering, university of colorado, boulder, colorado 80309, usa 2department of mechanical engineering, university of. Free cobol in enterprise developer personal edition.

Search the worlds most comprehensive index of fulltext books. This implies that it is not easy to achieve long focal microlens by simply enlarge microlens diameters because of photoresist thickness. Mar 02, 2015 abstract this video introduces a novel variable focus lens with a large optical aperture of 26 mm. Possible uses for such glasses are to provide inexpensive eyeglasses for people from lowincome groups, developing countries, third world countries or to accommodate for presbyopia. A variable focus lens also called zoom lens is a camera lens that can vary its focal length. If you are using indexed files, both the data and index files must be in the same directory. Some of the lens parameters are given in table 1 along with those of the other lenses described below.

Adlens called alvarez dual lens technology, this lens system features two thin, waveshaped polycarbonate plates that slide across each other by means of a small knob on the. Called alvarez dual lens technology, this lens system features two thin, waveshaped polycarbonate plates that slide across each other by means of a small knob on the frame. Variable focal length microlenses are of similar diameter to an optical fibre and so arrays find uses at both ends of an endoscope for imaging and operating on the surface of three dimensional biomass, for use as a high contrast spatial light modulator and for multiaperture confocal microscopes to avoid the need for mechanical optic axis scanning. The focal length, f, of mla could be described as eq. The applied voltage generates an inhomogeneous electric field near the hole regions. Microlens optics are 3dimensional elements embedded in optical light guides to provide customizable control of the uniformity and distribution of light. Inexpensive, simple fabrication method poised to expand microlens. This appendix lists all the environment variables that can be set when using the micro focus cobol system, and provides a brief summary of each one. It was quite simply an excellent event, due partly to the healthy diversity of speakers from eminent sages like keith wrightson to a gaggle of precocious grad students and partly to the uncharacteristically loose. Design and fabrication of long focal length microlens arrays. Professor wanjun wang is a spie fellow and associate editor for journal of micronanolithography, mems, and moems. Micro lens technology, was incorporated in north carolina on january 14, 1997 by ken conley. Our packaged aseries lenses are designed to make integration easier.

Variablefocusing microlens with microfluidic chip iopscience. A variablefocus liquid lens using a transparent flat cell is demonstrated. I have used near variable focus glasses such as sola access for hundreds of patients over the last few years. Yang h, yang c y and yeh m s 2007 miniaturized variablefocus lens. One electrode has a holed pattern while the other electrode is continuous. Tunable liquid gradient refractive index lgrin lens with two. Our microlens arrays are unique elements that may not be replicated or copied. Startup camera maker lytro offers something never before seen in the world of photography. This article introduces these kinds of variable focus lenses and expounds the problems to be solved.

The lenses assume an intermediate distance for the computer screen which is approximately at arms length. Focus stacking is a technique that allows you to combine multiple photographs with different focus distances to produce a single image with more of a subject in focus. News business business comment micro focus is a uk success story. My feeling is that there are several disturbing issues about them. After describing how certain problems in optics can be solved by liquid microlenses, the book introduces the physics and fabrication methods involved in microlenses.

May 01, 2017 variable focus moire lenses composed of diffractive optical elements does utilize moire patterns, making them ideal for a range of applications. Micro focus cobol workbench for the application developer. Fang et al 2005 ieee photonics technology letters 17 2643. Electrohydrodynamically actuated microlens is a category of microlenses that solely rely on solidliquid. The microlens consists of a thin diaphragm with 3d convex lens, chamber and microchannel, which are made of.

Brodie waddell last week i had the privilege of attending a workshop on writing microhistories at jesus college, cambridge. The focusing of light was achieved through the gradient refractive index grin. This article introduces these kinds of variablefocus lenses and expounds the problems to be solved. The assembly consists of a number of precisely stacked and aligned aluminum parts. We present a flexible variable focus converging microlens actuated by electrowetting on dielectric ewod. Pdms membrane microactuator for focal tunable microlens. A tunable focus liquid microlens array based on dielectrophoretic effect was demonstrated. Publications 35 this will count as one of your downloads. Compact variable focusing microlens with integrated thermal actuator and sensor j. Variable focal length lenses can be made by changing the shape of the lens, as is found in the human eye.

In april 2014, the company announced lytro illum, its second generation camera for commercial and experimental photographers. There is no need for mechanical and electrical integration of the liquid lens, enabling the variable focus capability to be integrated much faster into the customers system. Parylene intermediate layer is used to produce robust flexible electrode on pdms. In general, such lenses have a lower aperture than comparable fixfocus lenses. These potentially gamechanging glasses for presbyopes are called adjustable focus glasses also called adjustable focus reading glasses and variable focus eyeglasses.

A liquidfilled microlens array is used to replace the commonly used microlens. Simulation of electrowetting lens and prism arrays for wavefront compensation juliet t. Near variable focus lenses overwhelmingly preferred by. A tunable shackhartmann wavefront sensor based on a liquid. One of the goals for cobol was to make it possible for supervisors, managers and users, to read and understand its code. These novel photodetector arrays offer important advantages. Variablefocus liquid lens by changing aperture hongwen ren and shintson wu 2005 applied physics letters 86 211107. The variablefocus lens with variable refractive index mainly includes liquid crystal lens. Pdf variablefocusing microlens with microfluidic chip. Variable focus moire lenses trending in optics youtube. The study and application of microscale lenses and lens arrays enjoys a long history. The top substrate has an aperture which is sealed with a thin elastic membrane on the outer surface and the bottom aperture is sealed on the inner surface of the bottom substrate.

Polymerbased flexible microlens arrays with hermaphroditic. Combinations of microlens arrays have been designed that have novel imaging properties. Compact variablefocusing microlens with integrated thermal actuator and sensor j. Personal gripe on near variable focus computer glasses. Zoom lens simple english wikipedia, the free encyclopedia. We present a flexible variablefocus converging microlens actuated by electrowetting on dielectric ewod. Individual variable focus microlenses are of use in scanning multiple layers in a dvd or cd system where vibration can also be compensated. Adlens adjustable glasses are an exclusive frame and lens combination with a compound lens system that enables the wearer to focus on objects at any distance. Advances in microfabrication technologies in the past few decades have enabled the design and fabrication of microlenses and microlens arrays through many different approaches.

Kevin brearley, director, product management at micro focus, said. A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail. A novel design concept for a shackhartmann sensor is presented. Depending on the manufacturer common zoom lenses in the 30100mm focal range, for film photography usually have a varying aperture, from 4 to 5. Wu, tunablefocus liquid microlens array using dielectrophoretic effect.

Design and fabrication of an xray lens assembly for focusing xray beams is described. A variable focus lens also called zoom lens is a camera lens that can vary its focal length in general, such lenses have a lower aperture than comparable fixfocus lenses. A tunablefocus liquid microlens array based on dielectrophoretic effect was demonstrated. Variable focus microlens array based on dielectric elastomer actuator.

Another class of microlens, sometimes known as microfresnel lenses, focus light by refraction in a set of. Nov 21, 2014 the variable focus lens with variable refractive index mainly includes liquid crystal lens. The recent development of variablefocallength microlens arrays1,2 offers an interesting new method of switching on and off an array of optical probes with high. Micro focus cobol a powerful tool of old and modern. The thickness of the wall between adjacent cavities is 0. By cutting the assembled parts diagonally as shown below, a. Proceedings of the asme 2006 international mechanical engineering congress and exposition. Near variable focus lenses overwhelmingly preferred by computer users beaverton, or a new computer lens comparison survey conducted by ods in four different regions of the country found that subjects overwhelmingly preferred near variable focus nvf lenses to progressive lenses for computer use. The cobdata environment variable affects file deletes, using the rules given here, as well as file opens.

Some cameras, like the olympus omd em1, have this feature built in, so all you have to do is set up your shot and focus options and the camera will shoot and combine the images. Micro focus cobol is used also in many military or governmental agencies as well as in many commercial units, using different operating systems. If your mind is reeling at the thought of cobol and java cohabiting, things get even weirder. The development and outlook of variablefocus lens 2014. In recent years, there has been notably a host of exciting developments in the microlenses and microlens arrays, including tunable focus ones, those fabricated on nonplanar substrates and surfaces, and microlens arrays mimicking natural compound eyes, to name just a few. Simulation of electrowetting lens and prism arrays for. Pdf variablefocus liquid lens for miniature cameras. Electrowettingdriven variablefocus microlens on flexible surfaces. The top substrate has an aperture which is sealed with a thin elastic. The company is listed on the london stock exchange and is a constituent of the ftse 250 index. A cell structure that controls which substances can enter or leave the cell.

Added variable focus microlens array based on dielectric elastomer actuator, learning supportive system to electrical stimulation, pixelwise deblurring imagingpdi and research on advanced inspection of highways. These parts are cut from a long extruded section having sixteen parabolic cavities along its length. It also analyzes the developing trend of variable focus lens. The survey, conducted by prio corporation, took current wearers of premium. Adjustable focus eyeglasses have one focal length, but it is variable without having to change where one is looking. The variable focus lens with variable refractive index mainly includes liquid crystal lens. The small sizes of the lenses means that a simple design can give good optical quality but sometimes unwanted effects arise due to optical diffraction at the small features. Niederriter,3 alexander watson,2 ramzi zahreddine,1 and robert h. It also analyzes the developing trend of variablefocus lens. In recent years, there has been notably a host of exciting developments in the microlenses and microlens arrays, including tunablefocus ones, those fabricated on nonplanar substrates and surfaces, and microlens arrays mimicking natural compound eyes, to name just a few. This barcode number lets you verify that youre getting exactly the right version or edition of a book. Adaptive lenses have variable focal length performance and have been. We demonstrate a flexible, electrowettingdriven, variablefocus liquid microlens.

Micro focus international plc is a british multinational software and information technology business based in newbury, berkshire, england. If the session file is still not found, the current directory is searched. We start by considering relevant work by other authors on variable focal length lenses section 2, then we introduce our model for liquid crystal immersed lenses section 3. A new polymer microlens with variable focusing properties is designed and fabricated.