Afocal photography, also called afocal imaging or afocal projection is a method of photography where the camera with its lens attached is mounted over the eyepiece of another image forming system such as an optical telescope or optical microscope, with the camera lens taking the place of the human eye. Pdf afocal zoom lenses and their applications researchgate. Normal righthand sign conventions are used for each set of coordinates, and light. This will change the units of the metrics to be angular rather than distances.
Since beam expanders are afocal systems, make sure afocal image space is checked in the zemax lens data editor. The lens also has exit and an entrance pupils, as defined by an aperture stop 110. Strictly speaking, since ro and re are separated by a distance s, the apparent magni. Firstorder analysis of a threelens afocal zoom system. Tutorial of telecentric lens university of arizona. Afocal systems are used in laser optics, for instance as beam expanders, infrared and forward looking infrared systems, camera zoom lenses and telescopic lens attachments such as teleside converters, and photography setups combining cameras and telescopes afocal photography. But all of these software packages share one critical flaw. The movement of lens groups and the requirement to maintain good image quality at all zoom positions make zoom lenses design more challenging compared to. Afocal lenses with afocal lenses, somewhat dif ferent coordinate system origins and nomenclature are used, as shown in fig. Such telescopes are frequently used with some type of scanning sensor and require the pupil of the telescope to be external to it so that the sensor and telescope pupils can mate. The basic lens design forms are in here, and we can take a deep look into the development of lens design. Since the earliest and most common use for afocal lenses is as an. Each chapter is a great introduction for a specific optics subspecialties. The process starts with finding a thin lens solution, then a monochromatic thick lens solution.
Two wellknown afocal lens designs are the telescope and microscope, two lens systems that cannot be used to create an image without cascading an additional image system, similar to the function of the human eye. Analytical solution of an afocal two freeform mirror design. Modeling a 3 mirror 5x afocal telescope photon engineering. Key optical parameters of smart phone camera, typical design goal, design considerations, and design results are discussed. Field flattening astigmatism and field curvature, thick meniscus, plusminus pairs, field lenses 6 23. Although different types of afocal zoom sys tems have been designed and widely used in many optical systems, such as telescopes, viewing finders, optical scan. Afocal definition is having focal points infinitely distant. If the origins are at p and p 9, the coordinates will be given as x, y, s and x 9, y 9, s 9, where s 5 z 2 f and s 9 5 z 9 1 f. Also, some recent advanced product of telecentric lens or systems.
Cn102625920a afocal galilean attachment lens with high. Note that in fig 6 a and b the same afocal attachment has been reversed to provide two dif ferent focal lengths. Chapter 2 handbook of optics photonics research group. Electrostatic afocalzoom lens design using computer.
Wilhelm ulrich, carl zeiss ag, senior director optical design. Practical computeraided lens design by gregory hallock smith. Analytical solution of an afocal two freeform mirror. Awealthofreferences exists in that area, from introductory 3, 4, to intermediate and advanced 58. The process of designing lenses is both an art and a science. Basic principles about designing paraxial systems are introduced. The common design feature to notice is the larger the camera lens, the bigger the ep eyelens. The innovative lens design gives an unbeatable depth of focus to the wearer leading to clear images at all distances. The terrestrial visual afocal instruments glasses, binoculars have a reversing device, generally with prisms, between the lens and the ocular, which gives a positive enlarging. An afocal attachment reducing overall projector focal length by a factor of more than 3, comprising stationary, spaced lens elements in three groups, a positive group, a second slightly positive group and a third negative group, each group including at least one positive and one negative lens element, the negative elements having diameters at. Any kind of camera can be used for afocal photography.
The first and second lens groups are arranged to define a galilean configuration. A tutorial for designing fundamental imaging systems. Nevertheless, the optical designer may be called upon to design systems in which imaging has a minor role or no role at all. The rear focal point of the first system is coincident with the front focal point of the second system. The importance of the optical invariant in designing afocal lenses is discussed. This is an ultimate guide of lens design forms, the optical systems that are used in our world. Commercial imaging systems imaging systems for commercial applications such as camera objectives and projector lenses were one of the earliest application areas that benefited from optical design and analysis software. All are for folded zooms, which provide an interesting study. In a binoculars body, a set of two porros prisms enables a 180 rotation of the image around the optical axis and thereby straightens the images. One particular aplanatic design is the afocal case, in which the null spherical aberration implies that the plane input wavefront wfin is coupled to a plane output wavefront wfout stigmatically. Finally, we assumed the laser was a helium neon hene design and optimized for a design wavelength of 632. 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. Lens design fundamentals rudolf kingslake, applied optics and optical design part 1 and part 2 a.
The ultimate guide to lens design using the classic. A general analysis for the firstorder design of a threelens afocal zoom system with one lens fixed is presented. In both the single lens case and the afocal case the longitudinal magni. Rays parallel to the axis in object space are conjugate to rays parallel to the axis in image space. Pdf firstorder analysis of a threelens afocal zoom. Common afocal systems are telescopes, binoculars and beam expanders.
It means a very simple thing, putting the camera on the telescope ocular and taking shots. Pdf afocal zoom lenses are state of the art modules for magnification. Application of lens design fundamentals will almost always result in a preferable design and also provide guidance for the lens designer to controlredirect the optimization path being taken by the lens design program. Aspheres correction with aspheres, forbes approach, optimal location of aspheres, several aspheres 4 09. The reasonable solution areas in the focal length diagrams with positive or negative magni. Tilted and decentered reflective systems are easy to set up. The advantages of schemes like that are the easy scaling to high magnification range, good balancing of aberrations and diameters of lens elements and the high flexibility in. The lens adapter which screws on lens front is for 52mm filters so was also suited to the afocal adapter to present the eyepiece scarily close to the front element which does not move on zooming. A general analysis for the firstorder design of a three lens afocal zoom system with one lens fixed is presented. While advancements in the field over the past two centuries have done much to. This approach contains an afocal zoom with an accessible central stop surrounded by focusing lens groups placed on the object and or at the image side of the zoom. Continuing the bestselling tradition of the authors previous books, lens design, fourth edition is still the most complete. Focal equivalent conversion table for patients older than 66 y. A very important tool for designing lenses or complete optical imaging systems is optical.
Fitting guidelines for contact lenses for presbyopia with afocal design. Another design of the afocal zoom lens can be described as a fiveaperture lens consisting of two threeelement asymmetric lenses. The incidental laser beam to the slm is reflected and affected with phase modulation, then propagates to the shwfs via two afocal lens systems afocal lens system 1, afocal lens system 2. A tutorial for designing fundamental imaging systems koichi taniguchi opti 521 distance learning college of optical science university of arizona november 2009,, abstract this tutorial shows what to do when we design optomechanical system for imaging system. Smith, and optical system design robert fischer, introduction to lens design. Despite that, digital cameras are the best solution because you can immediately see the photo and learn from your mistakes on the spot. The focal points f and f 9, will be the origins for the coordinate systems x, y, z and x 9, y 9, z 9. In chapter 1, some fundamentals of geometric optics are introduced to help understanding lens. The abbe sine condition in its general form 7 states that for this afocal. But despite the fast lens, wide zoom range, manual focus to try both infinity and super macro with both the zeiss 8x and 10x kpl eyepieces. Focus fusion 1day presbyo gives wearers clear vision at far, intermediate and, importantly, reading. Practical computeraided lens design finds that magical balance between technical depth and accessible discussion of the journey from concept to finished optical design. Zoom systems mechanical compensation, optical compensation. The glass model for the design may need to be altered to match measured index data from samples of the real material.
After the design has been fabricated, there may be some additional steps necessary for precision applications. Another design of the afocalzoom lens can be described as a fiveaperture lens consisting of two threeelement asymmetric lenses. Telescopes and other visual systemstrue afocal modeling spaceborne systemsenvironmental analysis. Based on the principle of afocal zoom system, the laser collimation and beam expander system with a total length of less than 110mm, 6 pieces of spherical lens and a beam expander. For example, in chapter 7 we showed there can be four solutions for a spherically corrected achromat. An afocal system is formed by the combination of two focal systems. The reasonable solution areas in the focal length diagrams with positive or negative mag nification are derived and shown graphically. Code v optical design software design, optimize and fabricate reliable imaging optics. By optimal design of lens and structural components, high resolution can be realized, and perspective distortion can be minimized. In lens design with large computers, proceedings of the conference, institute of optics, government superintendent, rochester, new york. Lens designers have found it challenging to design highmagnification afocal telescopes that can operate simultaneously over very broad portions of the visible and infrared spectrums 12. Dec 19, 2006 a new cdrom accompanies this edition, offering extensive lens prescription data and executable zemax files corresponding to figures in the text. In optics an afocal system a system without focus is an optical system that.
Pdf lecture zoom and afocal systems waqas mahmood. Afocal zoom lenses and their applications article pdf available in proceedings of spie the international society for optical engineering october 2012 with 1,315 reads how we measure reads. Change contact lens accordingly using focal equivalent0. Fringe contrast improvement in twymangreen interferometer for lens test. What is afocal system uses of afocal system lens explained. How to design your own beam expander using stock optics. Pdf firstorder analysis of a threelens afocal zoom system.
Age 4042 4345 4647 4850 5152 5355 5657 5860 6163 6466 ref. Filled with sage advice and completely illustrated, lens design, fourth edition supplies handson guidance for the initial design and final optimization for a plethora of commercial, consumer, and. Some time ago i did an adaption of a sony tele converter which supposedly is of afocal lens design as it is to be mounted in front of a tele lens for use either directly on my panasonic fz200 as an alternative to my nikon tce17ed tc ore stacked with the nikon. This tutorial introduced the concept and set up for the objectspace telecenric system and imagespace telecentric system and advantages of telecentric lens that can impact the system performance. Request pdf on dec 1, 2014, omer sise and others published electrostatic afocalzoom lens design using computer optimization technique find, read and cite all the research you need on researchgate. The integration of modern computer optimization with classical qualitative and quantitative analysis makes this book an essential part of any optical designers library, from. The handbook of optics, from the optical society of america, is a tremendously valuable resource for all optics practitioners. Optical design method for afocal achromatic systems spie digital. Afocal digital holographic microscopy and its advantages. Although i have taken a great deal of effort to assure accuracy, the user of any of. Canons eos rebel sl3 eos 250d is the latest in the companys line of diminutive dslrs. In optics an afocal system a system without focus is an optical system that produces no net convergence or. The relation between the two separations of the three lenses in zooming is found to be a hyper bola.
But the not all the lens designs are simple lenses, we will look at newer and important lens design forms as well. Zero operands, lens splitting, lens addition, lens removal, material selection 3 02. Chapters relevant to lens design include doug goodmans chapter on generic principles of geometric optics, glenn boremans chapter on transfer function techniques, barry johnsons. An afocal galilean attachment lens 10 is disclosed, with the lens comprising, along an optical axis al, a first lens group 108 with overall negative optical power and a second lens group 109 with overall positive power.
With practical zemax examples joseph geary, are all great books, just to name a few. Optical design 1905 optical design is often identi. No distortion, high resolution, large depth of field, large field of view, high relative illumination, ir correction, high. Fitting guidelines for contact lenses for presbyopia with. Create and check lens and component drawings for the fabrication facility. With the optical design process outlined, we can examine how the specifics of the process can vary for different applications. Begin with a blank lens data editor with the stop set to surface 1. The following is not intended as a tutorial in how to use a lens design program. The main purpose of an afocal lens is to modify system focal lengths and so is generally used with other prime lenses.
The advantage of this design relative to the cylinder lens is its relative ease of construction, and the aberration coefficients can be further reduced. No distortion lens the designing and selection of the lens both are unique. As i described in a paper at the 2014international optical design conference, this class of optics is interesting be they are of a reasonable complexity that the designs are likely to be instructive, they offer a small range of design constraints because of the standardization of cmos imager sizes. Laser afocal zoom expander system due to the beam diameter variable, can be used in the light sheet illumination microscope to observe the samples of different sizes.