Every optical system requires some sort of preliminary design. Lens design used to be a skill reserved for a few professionals. The approach is general and fundamental, and is not limited to one. Wellchosen method for an optimal design of doublet lens. A combination of two lenses in contact, a converging lens made of crown glass and a weaker diverging lens made of flint glass, can be designed so that the combination is a converging lens that is almost achromatic. Continuing the bestselling tradition of the authors previous books, lens design, fourth edition is still the most complete and reliable guide for detailed design information and procedures for a wide range of optical systems.
Tips and tricks the doublet of the tessar is not for colour correction. Data are presented indicating the preferred crown glasses for use with 605380 and 689309 flint glasses, as typical illustrations of the qualitative aspects of the. And this is all human based lens design where the fun part, and most important part, comes before we do any computer optimization. Wellchosen method for an optimal design of doublet lens design wenshing sun,1, chienhsun chu,1 and chuenlin tien 2 1department of optics and photonics, national central university, 32001 chungli. May 01, 2014 in laserscanning microscopy often an offtheshelf achromatic doublet is used as a scan lens which can reduce the available diffractionlimited fieldofview fov by a factor of 3 and introduce chromatic aberrations that are scan angle dependent. Some manufacturers and designers makes derivative design from those, but coma remains negligible and the goal is to balance all aberrations for the best image quality. Proficiency with zemax does not guarantee success with modeling your optical system. Indeed that is the case in the design of an achromatic doublet lens. An achromatic lens or achromat is a lens that is designed to limit the effects of chromatic and spherical aberration. The ground loss will be nowhere as good as one over saltwater, but it is over wet, acidic ground, as the water table is at the surface there. Introduction to zemax entry with the lens data editor. Osa design of spherical aberration free liquidfilled.
Cemented achromatic doublets thorlabs cemented achromatic doublet lenses are available with antireflection coatings for the 400 700 nm, 400 1100 nm, 650 1050 nm, or 1050 1700 nm wavelength range. We also provide excellent suggestions for glass material selection in individual design as we distinguish the importance of refractive index precision in material selection stage despite the design data in software. An optimal doublet design to efficiently reduce both. Petzvaltype achromat is a design that uses two groups of lenses, with the rear group at to 23 of the focal length of the front group behind approximately. Designing doublet lens objective is quite complex procedure. Optik software winlens optical design software free winlens basic winlens. Achromats offer a nearly constant focal length across the visible spectrum, providing superior offaxis performance. The achromatic doublet design and analysis applet appears and you can inputchange the general doublet data, such as clear diameter, system focal length, edge thickness of the positive lens and center thickness of the negative lens. Smith reveals timetested methods for designing topquality lenses. A general method is described for choosing combinations of two optical glass types for the design of an achromatic cemented doublet lens which is required to yield specified amounts of thirdorder spherical and comatic aberration. The adl comprises a doubleconvex lens and a concaveplano lens and the related parameters of adl are preliminarily estimated by zemax software. Aug 15, 2017 at a given focal length the curves are steeper than a fraunhofer design, which is probably why recent examples of the design have generally been slower than average for their aperture.
Im attempting to source lenses for use in eyeglasses to deal with extreme sensitivity to chromatic aberration, and likely need either achromatic doublets or single lense. The goal here is a comafree airspaced doublet achromat contact type. And in general, with the present availability of optical raytracing software such as zemax or oslo a freeware version oslolt is available here, a dedicated amateur can play with may different lens designs and glass types, possibly evolving his or her own. An optimal doublet design to efficiently reduce both spherical aberration and coma will. To me, this is why lens design is fascinating the doublet lens. Tracepro is used for the design, analysis and optimization of optical and illumination systems. Practical computeraided lens design by gregory hallock smith. Answers to commonly asked questions about optical design, lens design, lens requirements and optics software. The achromatic design also helps minimize spherical aberrations. Achromatic and apochromatic refractor designs starizona. It is also important to understand exactly which zernike scheme a lens design software uses. Simulated focal spots for such a lens are shown in. The most common type of achromat is the achromatic doublet, which is composed of two individual lenses made from glasses with different amounts of dispersion. Inspired by doublet lens, we used three pdms polydimethylsiloxane membranes to form two cavities and filled in two kinds of optical liquid to make a doublet variablefocus lens.
There are many types of doublet lenses, but the predominant doublets are achromatic doublets, and. The secondary color for an achromat doublet lens is directly analogous to that for the achromat prism pair presented above. Rp photonics encyclopedia achromatic optics, lens doublets. Lets consider a spherical interface surface of radius r. And from the standpoint of using an achromat, i find it better to keep the lens robust and convenient. Mounting options we offer a full range of optical lens mounts to meet various experimental requirements.
Triplet vs doublet apo for visual astronomy page 2. This performance can be achieved over a broadband of wavelength. As optical designers widely use doublets which contribute latitude to eliminate chromatic and spherical aberrations more thoroughly. Use achromat lenses to minimize or eliminate chromatic aberration. Achromatic lenses are corrected to bring two wavelengths typically red and blue into focus on the same plane. Our achromatic lenses are offered mounted, unmounted, and in matched pairs. The doublet lens is the most simple and effective method for spherical aberration correction.
Dec 19, 2006 but all of these software packages share one critical flaw. Optimal lens design and use in laserscanning microscopy. A simple lens focuses different wavelengths of light to different points. In my own uncoated 8 f15 fraunhofer doublet, i have never seen a ghost image. After you get accustomed to geometrical optics, you may be interested in the lens design software such as oslo, of which edu version can be free downloaded. Achromatic doublet cmos miniature and fisheye lenses.
This video shows how to design an achromatic doublet in zemax this video builds upon the knowledge of how to solve for crown and flint focal lengths or radii if shape factor is selected. Doublet lenses offer users many more design options than singlet lenses, which allows for superior performance in visual imaging and laser beam manipulation applications. The stock lens matching tool will swap out the lenses in a design for the nearest equivalents in the selected vendors catalogs, and offers the potential to make great cost savings in the finished design by eliminating the need for custom manufacture. The doublet in the tessar corrects the field curvature and astigmatism. Modern lens design mcgrawhill professional engineering. Doublet refracting telescopes, or doublets, as they are commonly referred to, are simply just refractors that use 2 lenses to get a cleaner and more precise view. Wellchosen method for an optimal design of doublet lens design wenshing sun,1, chienhsun chu,1 and chuenlin tien 2 1department of optics and photonics, national central university, 32001 chungli, taiwan r.
Specifically, red light is focused farther from the lens than blue light. In our research, the back focal length, effective focal length, and the semidiameter of the achromatic doublet. These latest advances allow more people to design lenses than ever before. An achromat lens, is designed by either cementing two elements together or mounting the two elements in a housing, creates smaller spot sizes than comparable singlet lenses. Tips for designing manufacturable lenses and assemblies. The doublet should be at the optimization level with respect to its optical quality.
Design and optimization of the metasurface doublet lens. Delving deep into the mechanics of lens design, optics legend warren j. Contact our multilingual technical sales team and discover how knight opticals high quality custom achromatic doublet lenses. Our design for the achromatic doublets uses the helium d line 587. There are many zernike schemes, all inconsistent with each other, and with slightly different expressions and. The job of an optical lens designer is to design the lens system, either by designing a lens or multiple lenses into a system. In many cases, it is not sufficient to use a simple doublet lens. Doublet refracting telescopes top brands lowest prices. This design uses a longfocalratio over f10, lowdispersion doublet in combination with two elements farther down the optical path which speed up the focal ratio and flatten the field. So much to write about for a simple singlet lens system. Adhering to the aim to create unique product design for customers, hyperion optics has devoted itself to achromatic doublet design and other achromatic doublet related products for many years. Imaging is the most important application sector for achromatic optics. Wellchosen method for an optimal design of doublet lens design. Designing an achromatic doublet physics libretexts.
Continuing the bestselling tradition of the authors previous books, lens design, fourth edition is still the most complete. Zemax tutorial 1 lens data editor interface youtube. The standard or noll zernike and fringe zernike schemes are just two zernike schemes often used in lens design. Achromatic lenses thorlabs achromatic lenses cover the 240 410 nm, 400 700 nm, 650 1050 nm, 1050 1620 nm, 3 5 m, and 8 12 m wavelength ranges. A secondary dispersion formula is utilized to sort out minimal longitudinal chromatic aberrations for the doublet. The lens power factor of the first lens in a fraunhofer type doublet normally lies between 1. There are many zernike schemes, all inconsistent with each other, and with slightly different expressions and coefficients. The high number of degrees of freedom allow this design to be very well corrected, even at speeds as fast as f5. They come in mounted and unmounted options, as well as matched pairs and kits. Quality achromatic doublet lenses commercial doublet lens. The main application of achromatic optics in particular, on a chromatic lenses is in imaging systems, as needed for photography, microscopy and video recording, for example. After computing the initial dimensions, putting the design into lens design software. Strategic use of this doublet is useful in any lens design, but is particularly useful for and retrofocus lenses, telephoto lenses, and zoom lenses. Depends on how sensitive you are and how bothered you are by chromatic aberration and false color.
For a more basic overview of this design please see therefractors page. Doublet liquid variablefocus lens for spherical aberration. Step by step procedure for preliminary design of comafree doublet achromat. We stock a range of doublet lens sets for ease of use in a laboratory and design environments. Modas stands for modern optical design and analysis software it is a telescope design software of the most popular telescope systems used by the amateur astronomers and telescope makers, including spot diagrams, ray fans, wave aberrations, diffraction analysis, optical layout, optimization, tolerancing, mirror testing and many other atm tools. Practical computeraided lens design tells how to design and evaluate lenses using computers. This guide will tackle how lens design was done before optical design software on computers were invented, which i will call the classic method for lens design. This modeling method does require surface measurements of the lenses, resulting in additional time and effort, and therefore expenses. Apo is a three lens design is a good choice for you. In optics, a doublet is a type of lens made up of two simple lenses paired together. Its amazing to imagine people used to do this by hand, abacus or not.
The lectures will cover lens design, aberrations, optimization, tolerancing and image quality metrics. However, the design of an achromatic doublet lens lends itself to the sort of calculation we are doing in this chapter. Optical systems design 3 zemax optics studio the zemax optical design program is a comprehensive software tool. Such an arrangement allows more optical surfaces, thicknesses, and formulations, especially as the space between lenses may be considered an element. In our research, the back focal length, effective focal length, and the semidiameter of the achromatic doublet are set as 60 mm, 100 mm, and 37. Determine the best machine vision lens for your application by simply providing your camera, working distance, and field of view. Nov 28, 2016 design and optimization of the metasurface doublet lens. How can i compute front focal length of cemented doublet. Newports visible achromatic doublet lenses are design around the following visible wavelengths 486. Achromatic doublet consisting of a crown equiconvex lens cemented to a negative flint glass lens r 11 r 12 21 r 22 n 1 n 2 lets assume we want an achromat doublet of 15 cm focal length. These telescopes can also be classified as apochromatic or achromatic depending on the scope itself. Achromatic doublet lenses achromat are designed to eliminate chromatic and spherical aberrations inherent in singlet lenses. The approach is general and fundamental, and is not limited to one specific software program. Imaging lens selector our lens selector tool makes finding the right imaging lens easy.
Registration form cmos miniature and fisheye lenses. The ultimate guide to lens design using the classic spreadsheet method. There are many types of doublet lenses, but the predominant doublets are achromatic doublets, and they correct the chromatic aberration. Values represent theoretical values from lens design software. I have a single lens refractor that creates huge amounts of chromatic aberration. He deals with lens design software, primarily oslo, by far the current market leaders, and provides 7 comprehensive worked examples, all new to this edition. Feb 12, 2014 this video shows how to design an achromatic doublet in zemax this video builds upon the knowledge of how to solve for crown and flint focal lengths or radii if shape factor is selected. But all of these software packages share one critical flaw. Thorlabs cemented achromatic doublets are optimized to provide excellent performance in the visible region. You can see how a new design can evolve around a simple starting point idea or structure. Figure 1a schematically shows focusing by a sphericalaberrationfree metasurface lens.
In actuality, a mechanical engineer or mechanical designer can also design a lens system with the knowledge of paraxial lens design. To introduce the design principles of lens and mirror optical systems and the evaluation of designs using modern computer techniques. Although the calculation methods are classic, with the help of a spreadsheet, we will do a stepbystep lens design that makes all of the steps and theory make sense. The advent of the personal computer and affordable optical design software has extended this revolution. Free version of the winlens3d optical design package, which provides serious design and analysis tools for optical engineer, student or designer. There is no shortage of lens optimization software on the market to deal with todays complex optical systems for all sorts of custom and standardized applications. Other doublet lens designs are flat on one side planoconcave designs, and one can also realize defocusing achromatic lenses negative achromats. Find examples for detector systems, selecting the right lens, and building a projection.
How can i compute front focal length of cemented doublet lens. Its a large aperture, lowloss design, at a reasonable height, with a total system efficiency probably over 95%, not counting ground loss. Zemax delivers design software, training, and support services that set the highest standards for the optical and illumination industries. In summary, we can see that for a given set of glasses, the design process works by altering only three parameters. When used onaxis, an achromatic lens focuses an parallel input beam to a perfect point, limited only by the effects of diffraction. A systematic design idea for liquidfilled cylindrical zoom lenses with ideal imaging quality over a wide focal length range is introduced in detail. They employed company proprietary optical design and analysis software which was resident on large and expensive mainframes. Finding the radii concludes preliminary design process. Conceptual lens design by the masters, without using expensive software, but a spreadsheet. In some cases, a lens doublet is not contacted, but the two lenses are only placed in a common housing airspaced doublets.
These doublet lens sets are more economical to buy compared to buying as individual lenses. I can understand the front focal length of cemented doublet lens will be the same with bfl if each parts of lenses were consist with same materiale. We offer achromatic doublets, cylindrical achromatic doublets, and airspaced achromatic doublets, as well as achromatic triplets that allow for maximum aberration control. For f10 systems such preliminary design could be quite usable without optimization, but it is always a good idea to confirm that with ray trace.
520 1179 780 119 989 758 286 1490 17 1093 219 647 1310 282 1475 1133 921 161 37 586 1221 874 1275 1280 780 623 29 395 808 36 1343 1460 1278 124