A typical CIM architecture consists of several standalone software applications which are integrated to provide a complete automated manufacturing environment. An essential component of CIM is a geometrical database that contains the models of systems and their components. All the individual applications must interface with that database, and direct interface to other software tools is an advantage. Traditional major components of this environment include a CAD/CAE system and a CAM system. The relationship between the two is clear, the CAD/CAE component produces a design which is transferred to the CAM component for production. An optical system contains two types of elements, optical and mechanical, with disparate design and manufacturing methods. The paper discusses the optical CIM environment and the basic components that it requires.
We summarize the requirements for a stereoscopic microscope as part of an investigational excimer laser corneal sculpting apparatus, describe how a Zeiss surgical microscope was integrated into that apparatus and report the in situ optical performance of the microscope.
The long range observation system (LROS) is based on Ritchey—chretien telescope that was designed, built and tested by ELOP. The telescope is rxunted inside a sealed external structure with large entrance window. The concept adapted in the LROS design is to divide the mechanical structures into two major assemblies: — Internal optical bench that supports the sensitive optical elennts . This bench is based on a structure made of composite material. — External body that protects and seals the internal optical structure. This structure includes large entrance window and interface flanges that can be supported on mba, tripod or a pedestal. The key to this design was to properly select and size these two structures in order to achieve the nost rigid but light—weighted structhre . This paper describes the study that was made to specify design criteria and to analyse the design according to these criteria.
This paper describes the design and performance of an automated, closed-loop, laser beam alignment system. Its function is to sense a beam alignment error in a laser beam transport system and automatically steer mirrors preceding the sensor location as required to maintain beam alignment. The laser beam is sampled by an optomechanical package which uses video cameras to sense pointing and centering errors. The camera outputs are fed to an image processing module, which includes video digitizers and uses image storage and software to sense the centroid of the image. Signals are sent through a VMEbus to an "optical device controller" (ODC), which drives stepper-motor actuators on mirror mounts preceding the beamsampling location to return the beam alignment to the prescribed condition. Photodiodes are also used to extend the control bandwidth beyond that which is achievable with video cameras. This system has been operated at LLNL in the Atomic Vapor Laser Isotope Separation (AVLIS) program to maintain the alignment of copper and dye laser beams, the latter to within tr in pointing and less than 1 mm in centering. The optomechanical design of the instrumented package, which includes lens, mirror, and video mounts in a rigid housing, the automated control system architecture, and the performance of this equipment is described.
Advanced composites have been effectively used in space applications such as telescopes, optical benches, and metering structures. As the sophistication of optics and instrumentation increases, the need for near-zero outgassing and extremely dimensionally stable composites becomes of paramount importance. Continuing improvements in resin and reinforcing fiber technology have resulted in a wider selection of materials for the composite designer of dimensionally stable structures. Additional improvements in metal sealing techniques promise unprecedented long-term environmental stability. These new options allow the designer to develop a dimensional stability strategy which conforms to design requirements and yields an optimum, cost-effective composite design approach. This paper addresses the major stability issues in composites and how stability can be predicted for long-term applications, along with design options to achieve program goals. Low-moistureabsorbing composites based on cyanate esters, metal sealing techniques, and long-range stability are also addressed.
A testing program was conducted to determine the long term temporal stability properties of sheet Invar. The tests were conducted at the University of Arizona's Optical Sciences Center over a period of 9 months. Growth measurements were made using an interferometric optical technique at both ambient and elevated temperatures. Eleven specimen types, in groups of three, were included in the test. These data were combined with published historical data to establish an estimate to the long term behavior. It was found that Invar exhibits short term behavior with a rapid initial growth rate, 8 - 12 ppm/yr and time constant on the order of 100 days plus long term exponential growth at lower growth rates, 2 - 5 ppm/yr initial (end of year 1) with a three to eight year time constant. The parameters which most significantly effect Invar growth rate were found to be: time since final heat treatment; carbon content; heat treatment; and, ambient temperature.
Control of an ion beam for milling optical surfaces is a nontrivial problem in two-dimensional deconvolution. The ion milling operation is performed by moving an ion beam gun through a grid of points over the surface of an optical workpiece. The control problem is to determine the amount of time to dwell at each point in the grid to obtain a desired surface profile. This research treats the problem in linear algebra terms. The required dwell times are the solutions to a large, sparse system of linear equations. Traditional factorization methods such as Gaussian elimination cannot be used because the linear equations are severely ill conditioned. Theoretically, a least-squares solution to this problem exists. Practical approaches to finding a minimal least-squares solution are discussed.
Ion beam milling is an emerging advanced optical fabrication technology capable of deterministic figuring of optical surfaces. Much of the work in ion milling to data has emphasized figuring of glass-like materials, such as fused silica, which do not significantly roughen during ion milling. However, for ion milling to reach its full potential as an advanced optical fabrication technique it must be applicable to a broad range of materials to interest in optical fabrication including polycrystalline metals, semiconductors, and ceramics. In order to assess the feasibility of ion milling, the effect of ion dose on roughness evolution was investigated for a variety of materials including: silicon, germanium, sapphire, silicon carbide, fused silica, aluminum, and copper. Single crystal silicon, germanium and sapphire as well as polycrystalline CVD silicon carbide did not significantly roughen during ion milling. The roughness evolution of aluminum, copper and gold thin films were also studied; fine grained gold films were found to remain smooth during ion milling.
The construction of a very large optical telescopes can be prohibitively costly due to the massive weight of conventional primary mirrors. The cost of such telescopes can be reduced by the use of a segmented lightweight primary mirror. An Itek process, computer controlled optical surfacing (CCOS), is ideally suited for manufacturing the off-axis aspheric segments. During CCOS operations, a subaperture tool is moved across the optic surface under accurate computer control. By altering the time that the machine grinds or polishes each surface region, accurate and rapid figure progress can be achieved. This CCOS technology is described including machine control, figuring process, pad-to-surface fit, vacuum grinding/polishing, and optic edge figuring. The utilization of CCOS to fabricate seven similar, thin, 2-meter, off- axis, aspheric optics and a lightweighted, active, off-axis mirror is related. Also, the paper summarizes the ongoing manufacture of a large active off-axis aspheric.
In this paper, we design a new method, which can accurately and efficiently finish the small and soft semiconductor plano-convex lens. Special features of this process are as following: (1) A scratch-free and smooth surface produce. (2) A precision blocking jigs has been constructed which enables the operators to adjust the wedge angle of plano-convex lens precisely. (3) A rapid testing method of wedge angle has been studied.
A variation of the Ritchey-Common configuration was applied to the subaperture testing of a 29-in diameter flat at about 65 degrees oblique incidence in the 12-in collimated beam of a Fizeau interferometer, yielding an elliptical beam footprint spanning the full diameter of the mirror under test. A set of subaperture samples was built up in a 'flower petal' pattern symmetric about the mirror center by in-plane rotation of the mirror in 30-degree increments. A key advantage of this method of sampling over raster methods is that the synthesis of the full surface map is greatly simplified by not having to keep track of individual piston and tilt terms because of the symmetry. An advantage over the Ritchey-Common configuration is that the cavity length can be made much shorter, thus greatly reducing atmospheric effects. The data reduction and surface synthesis processes simply consisted of fitting Zernike polynomial expansions to the (digitized) individual interferograms, subtracting the piston and tilt terms, then applying rotation and scaling transformations to the pupil coordinate grid to map the (circular) pupil surface data into the appropriate elliptical footprints.
A primary function of compact disk measuring systems is the measurement of various types of defects which represent either functional or cosmetic flaws and the measurement of the profile of the compact disk. Functional flaws can make a very bad interference with the reproduction of the recorded music. Cosmetic flaws are visual imperfections whose presence can cause the rejecting of the disc by the production line. A projection moire method is invented in which a light beam passes through a grating, and is projected onto the object by overlapping with the virtual grating in the computer software. The object's 3-dimensional profile will be reconstructed and the object's profile quality can be improved by our new method for moire image processing.
Our group has developed a surface roughness measuring system for supersmooth optics based on scanning tunneling microscopy techniques, which includes the assessment of two dimensional and three dimensional surface roughness parameters. The system has been applied to topographic mapping of superpolished Si wafer coated with single layer Mo film. The measuring precision of measured Rms, Ra and P-V value, if expressed with standards deviation (sigma) s, is 0.06 nm, 0.05 nm and 0.19 nm, respectively, which has achieved atomic resolution.
The aspheric surfaces can be tested with using the interference type computer--generated holograms (CGH). However, the system errors which exist in optical arrangement affect the measurement result. For this reason, this paper proposes a new method using CGH to compensate the system errors, in which Zernike polynomial analysis and calculation are applied. The method is verified by experiment.
An experimental set-up of H-S (Hartmann-Shack) wavefront sensor using an ICCD (intensified charge coupled device) as a photon detector is introduced. The centroiding errors of image spots caused by discrete and limited sampling, photon noise, and read-out noise are analyzed theoretically and experimentally.
The third-order vector aberration theory developed by Roland Shack, and later extended to fifth order by Kevin Thompson, is adapted to a personal computer spreadsheet program. Several examples are given to illustrate the ease of application of this approach to the analysis, and in some cases optimization, of a variety of tilted and decentered systems. These include an afocal pupil relay system using three off-axis parabolas, a similar system where the third parabola is replaced by an off-axis ellipse, and a tilted component IR lens. The results of the spreadsheet analyses are compared with similar results obtained from a commercial lens design program.
Many methods exist for the optimization of lens systems. A great number of these are based on the successful damped least squares (DLS) algorithms. The success of the DLS optimization algorithm applied to optical design has tended to conceal fundamental limitations in the method. The DLS optimization method relies upon the selection of weights for each of, typically fifty aberrations and an optimum choice of these aberration weights is essential in order to achieve both the best possible performance and to guide the design process during convergence. Selection of suitable damping factors is also important for successful convergence towards an optimum solution and is considered here as a dynamic weight adjustment routine based on feedback techniques, to both increase the rate of convergence and improve the quality of the final lens design.
The first-order Double-Gauss 4 element objective arrangement derived from a triplet type by splitting the central negative element is discussed. The Petzval sum of the lens system was chosen and calculated. With desired axial color, glasses will be selected and axial color calculated. By using the aspherical coefficients, we discuss the aberrations compensation. Following the design procedures to design a camera objective, the lens data after optimization and the MTF curve are presented.
A new method for optical microscopy with super-resolution exceeding the Rayleigh limit was developed to observe the shape of particles contaminating the LSI patterned wafer in the far- field. The principle of the new method is as follows. The optical spot being smaller than the measured particles has to be scanned on the particle to measure the shape of particles on the wafer. The phase-shifting mask making small optical spot consists of the checkered mask which has been coated with a transparent layer patterned to ensure that the optical phases of the nearest apertures are opposite. The destructive interference between the two opposite phases of light waves from adjacent apertures cancels some diffraction effects and increases the spatial resolution, so that the size and resolution of the coherent laser spots can exceed the size limit of the Airy disk and resolution of Rayleigh limit. The new method for optical microscope with super resolution was examined theoretically and experimentally. The coherent beam generated from 15 mW He-Ne laser projected to the phase-shifting checkered mask forms small laser spots of which size are under 0.1 micrometers in diameter. It is clarified that in the far-field, the scattered light from two spots with opposite phases on the wafer can be observed in exceeding with Rayleigh limit.
This paper describes a new design method for athermalized optical systems. It can be accomplished by combining optical materials and by selecting suitable lens powers. However, there are difficulties in determining material and power of each lens, because achromatism is simultaneously required. To determine the condition of eliminate thermal focus shift and longitudinal chromatic aberration easily by simple drawing, an athermal chart is proposed which is constructed by plotting chromatic dispersive power and thermal dispersive power on a cartesian coordinate system.
From lasers to spectrophotometers, reflecting microscope objectives are today finding a wealth of applications: reflecting objectives are widely used in the UV microlithography as well as in FTIR spectrophotometry, as part of the delivery system to focus the beam to precisely controlled spot sizes (e.g., for excimer laser beams--submicron size). Because of achromatism these objectives can be used simultaneously for aligning and viewing the targets. In the 'classical' layout the smaller mirror obstructs the central portion of the incident beam. The current paper describes a new solution to reduce the central obstruction by incorporating refracting components in the objective construction. We will discuss the conditions for aberrations correction and diffraction limitation as a function of both the focal length and aperture. Some examples of reflecting/refracting objectives (RRO) will be presented.
Replicated optics have been available since the 1950's. We recently undertook the development of 'supersmooth' (surface roughness <EQ 5 angstroms rms) replicated optics. This work has involved the replication of large optical flats. Measurements to determine the roughness of the surface have indicated that our process imparts an increase in surface roughness of less than 2 angstroms rms to a flat replica. We did not determine the absolute roughness of the surface but are able to show that the change in surface roughness was consistent between the two techniques used. Current work involves the replication of spherical and off axis parabolics.
The Optical Sciences Center, University of Arizona, has designed and constructed a unique 'red corrected' astrometric astrograph objective lens for the United States Naval Observatory. A five element design, with an integral Schott OG550 filter, was developed to meet the requirement for a 2060 mm focal length, f/10 system. The lens provides a nearly zero distortion flat field of 5 by 5 degrees in the sky. A weight limit of 55 kg led to the use of a titanium lens barrel. Assembly tolerances are satisfied through the use of elastomeric subcell mounting of the individual elements, and an adjustable final element. The lens is hermetically sealed and uses a filter/dessicator system to insure the long term cleanliness of the optics.
The use of partially transmitting mirrors for high-power laser radiation, especially in laser cavities, requires substrates with very high-quality surfaces to avoid laser damage. The damage can arise from local increase of electro-magnetic field strength and absorption in the thin film coating and in the bounding layer of the substrate material. Therefore, extremely fine polished surfaces are needed. For YAG-laser-application at 1064 nm mostly quartz materials are used which require optimized tooling and techniques for the polishing process. The optimization of this process is achieved by identification and subsequent systematic variation of the main polishing parameters. The resulting surfaces are tested with respect to micro- roughness, light scattering and laser damage threshold both for uncoated and coated substrates. It will be shown that the damage threshold of laser mirrors can be increased by more than 100% compared with conventionally produced surfaces. Extreme threshold values can reach the damage threshold of the pure substrate material.
The determination of ophthalmic lens quality using traditional focimeters is highly subjective as it relies on the visual sharpness of a target image. The moire deflectometer displays a distribution of focal powers across the lens aperture, making possible the definition of objective quantitative criteria for lens quality. The shape of the fringe pattern is used to discriminate between inherent features such as spherical aberrations, and other defects due to design or manufacture. Interfacing the fringe image with a computer using specially designed image processing software produces a fully automatic system for the determination of lens power and quality. The new method was tested on samples of soft contact lenses measured in saline. The same principles can also be used for spectacle and other types of simple and compound lenses.
An unstable resonator with semitransparent output coupler (NRPOZ) and low magnification is investigated theoretically and experimentally for Fresnel numbers 5 - 15 and small signal gain 0.5 - 2.4. With the help of numerical simulation the condition of minimum diffraction losses is found. The beam divergence in the dc-discharge transverse-flow kilowatt-power CO2 laser was approximately two times less in comparison with telescopic unstable resonator without substantial loss of mode volume and output power.
The eye-safe (500 nJ per pulse) portable lidar with a wavelength of 0.840 micrometers has been designed. Operating as a photon counter, it allows to measure a distance to objects within a 5 km range with an accuracy of 5 m and backscatter coefficients with an accuracy of 2 * 10-7 (msr)-1. Results of some applications are presented.
A scheme of an optical switch using a matrix of reprogrammable holograms is discussed. The light from each input channel is deflected to an output channel with a separate microhologram. The microholograms are recorded and overrecorded with two acousto-optical deflectors on a bacteriorhodospin photo medium. The experiments have been carried out on a prototype with 20 X 20 channels. As shown, the capacity of such a switch can be increased up to 104 X 104.
In this article the emergence, development and present of depolarizer has been studied by me. Then I have studied the all quartz depolarizers existing presently. Such as single plate depolarizer, loyt depolarizer, single wedge depolarizer, right angle prism depolarizer, J.C. kremen double wedges depolarizer by theoretical analysis and experiment measurements. I have found when the polarization plane of the incident monochromatic light is unknown or frequently varies, the emergent light can not be depolarized completely by using all the existing depolarizers. According to this situation, I have invented a new type of double wedge depolarizer. I can depolarize the emergent light completely whether the polarization plane of the incident is known or frequently varies by using the new depolarizer. The polarization degree of the emergent light is below 1.0%, transmission ratio is above 90%.
A little displacement polychromatic parallel non-polarization beamsplitter, which is composed of two elements, has been introduced in this article. It has been studied by theoretical analysis and experiment, and has been given the optimal structure. The displacement of the beamsplitter can be designed in need, which is about 1.0 - 3.0 mm. The polarization degree of the emergent light is below 1.2%, transmission is above 90%, transmission range is from 300 nm to 2500 nm. Its structure is simple, making convenient and loss low.
Low polarization beamsplitter has been reported by article and patent in Applied Optics in 1983. Which structure is a quartz birefringent plate, it can be used to splite beam by using the reflection and refraction of the surface of the birefringent plate. In this article I have introduced a polychromatic adjustable beamsplitting angle low polarization prism, which is composed of four elements. I have studied it by theoretical analysis and experiment measurement. Whose character is: (1) the beamsplitting angle can be adjustable continuously, (2) transmission is high, (3) the intensities of the two beams are about equal, and, (4) the adjusting is convenient and reliable. Such as a 37 degree(s) prism, the beam splitting angle is from 15 degree(s) to 45 degree(s), transmission is above 85%, the maximum polarization degree of the emergent light is below 10%. The range of the beamsplitting angle can be designed in need.
I have studied the transmission range of the existing depolarizer in this article and found we can depolarize visible light completely by using Calcite or Quartz depolarizer. But we can not depolarize near infrared and middle infrared light completely by using the existing depolarizer. According to this theory, I have invented a new type of monochromatic light magnesium fluoride double wedges depolarizer. Its structure is different from the quartz double wedges depolarizer. I have studied it by theoretical analysis and experiment measurement. I can depolarize the light completely whether the polarization plane of the incident light is known or frequently varies by using a new type of magnesium fluoride depolarizer. The polarization degree of the emerging light is below 1.0%. It can be used in the near ultraviolet, visible, near infrared and middle infrared light.
Main stages of electro-optical devices (EOD) energy calculation are presented. Generalized methodology of the energy calculation permits to find simply a set of important EOD parameters, for example, a threshold sensitivity, a detection range, construction parameters of an optical system, detector and electronic scheme.
The Center for Optics Manufacturing (COM), established in 1989 at the University of Rochester's Institute of Optics, is a strategic collaboration of the APOMA (American Precision Optics Manufacturers Association), several academic institutions (Arizona, Central Florida, and Rochester), and the U.S. Army Material Command. This focused alliance is forging the optics industry's course for continuous improvement through novel manufacturing programs that provide the next generation technology, processes, and interactive training necessary to drive industry competitiveness to new levels.
The Center for Optics Manufacturing (COM) Process Science development program has advanced the current state of the art in optics manufacturing. Initial data indicates that the newly developed deterministic microgrinding process will generate specular optical surfaces. Deterministic microground surfaces, with 100 - 300 angstroms surface finishes, 1 - 2 microns of subsurface damage, and 1 wave peak-to-valley surface figure, have been produced on a range of glass types. Total cycle time, using a modified machine, took an average of five minutes per surface from start to finish. The high speeds, slow infeed rates, precision spindle, and computer control that were required to produce these microground surfaces could not have been achieved on current conventional equipment, thus emphasizing the importance of the Center's Process Science program.
Rank Pneumo has worked in cooperation with the Center for Optics Manufacturing at the University of Rochester and the Center's Manufacturing Advisory Board to develop a flexible CNC machining center for spherical lens fabrication. The prototype Opticam SM machine has been built and delivered to the Center for Optics Manufacturing. The machine is currently undergoing process and cycle development at the Center. Opticam SM experiments have demonstrated the ability to grind surfaces of less than 200 angstroms rms, subsurface damage less than 2 microns, and a surface figure better than 1 wave p-v in less than five minutes.
Rank Pneumo has worked with the Center for Optics Manufacturing and the Center's Manufacturing Advisory Board to design a multi-axis prism grinding machine. The Opticam PM is a three axis, high precision CNC reciprocating grinder. It is designed for the automated manufacturing of glass prisms. Unique features of the design incorporate electrolytic in- process dressing of the finishing wheel, nested grinding wheels and machine resident metrology to provide RQM (Real-time Quality Management).
Although the principles of concurrent engineering and rapid product cycles are not new concepts in the industrial sector, the optics manufacturing industry has witnessed few technological advances since the 1940's. At present the optics industry maintains outdated stand-alone manufacturing equipment and systems that do little to foster integration or communications. 'Islands of Technology', spawned from the latest offerings of CNC controlled equipment, are generally stand alone systems incapable of supporting communication with other process equipment, not to mention the total business enterprise. This approach increases the cost in design and manufacture of optical systems while negatively impacting competitiveness in the global marketplace.
A uv-curing 'cold' blocking adhesive has been developed by Loctite Corporation for use with the Opticam SM. The adhesive is a significant advance in the lens blocking process, as it eliminates heat-induced blocking strain; the most significant problem encountered with current hot pitch blocking methods. The new cold blocking adhesive is complemented by a new Kennametal lens blocking adapter tool and chucking system. The tooling offers substantially improved lens adapter to machine alignment and transfer; at considerably lower cost. The lenses are deblocked in a heated water and detergent solution, eliminating the environmental concerns of the current method.
The formula for evaluation of narcissus equivalent temperature difference as a function of the scan angle in thermal imaging systems is made more meaningful by grouping the parameters in two factors: one depending on wavelength and temperature and the other, a function of the scan angle, depending on the geometry of the instrument. Exact ray tracing equations are used to evaluate the ratio of radiant energy reaching the detector from warm and cold areas of the instrument.