This PDF file contains the front matter associated with SPIE Proceedings Volume 10590, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

The lens design problem for the 2017 IODC is to design a lens which includes a "100 lens" to commemorate the OSA's 100th anniversary. Traditional lens specifications (focal length, f/number, field of view, etc.) are not specified; the goal of the problem is to maximize the used diameters of the ball lenses in the 100 lens while maintaining diffractionlimited optical performance. The winning entry from Takeshi Akiyama has 54 lens elements, is 19,443 mm long and 165 mm in diameter, yet has a focal length of only 0.02 mm; it has a merit function of 398.04 out of a maximum possible 400.

For the 4th time, the International Optical Design Conference (IODC) included an Illumination Design contest. This year, the contest involved designing the illuminator to produce a “100” logo to celebrate the OSA’s 100th anniversary. The goal of the problem was to produce the highest logo luminance with greater than 30% uniformity. There were 7 entries from 2 different countries. Two different commercial optical/illumination design packages were used. The winning solution, was provided by Steve Mulder.

System assessment for design often involves averages, such as rms wavefront error, that are estimated by ray tracing through a sample of points within the pupil. Novel general-purpose sampling and weighting schemes are presented and it is also shown that optical design can benefit from tailored versions of these schemes. It turns out that the type of Gaussian quadrature that has long been recognized for efficiency in this domain requires about 40-50% more ray tracing to attain comparable accuracy to generic versions of the new schemes. Even greater efficiency gains can be won, however, by tailoring such sampling schemes to the optical context where azimuthal variation in the wavefront is generally weaker than the radial variation. These new schemes are special cases of what is known in the mathematical world as cubature. Our initial results also led to the consideration of simpler sampling configurations that approximate the newfound cubature schemes. We report on the practical application of a selection of such schemes and make observations that aid in the discovery of novel cubature schemes relevant to optical design of systems with circular pupils.

Quadratic pupils representing Gaussian apodization and defocus are expanded into Zernike polynomials. Combinations of the pupil expansion coefficients are used, in turn to expand the Optical Transfer Function into a novel set of basis functions.

In this work, we show how to predict the polarization-performance of high-numerical aperture optical systems. Various important influences, such as coating-induced phase change, stress induced birefringence, or the quality of the raw material are investigated.

A glass selection optimization algorithm is developed for primary and secondary color correction in thick lens systems. The approach is based on the downhill simplex method, and requires manipulation of the surface color equations to obtain a single glass-dependent parameter for each lens element. Linear correlation is used to relate this parameter to all other glass-dependent variables. The algorithm provides a statistical distribution of Abbe numbers for each element in the system. Examples of several lenses, from 2-element to 6-element systems, are performed to verify this approach. The optimization algorithm proposed is capable of finding glass solutions with high color correction without requiring an exhaustive search of the glass catalog.

With the move to more and more lightweight and cost-effective design, a move to multiband or multi-spectral optics is required. These systems are becoming more prevalent in the market as new detector technologies have been developed. However, the lens designs are only starting to be considered with the addition of new materials in the MWIR and the LWIR. For the VIS/SWIR region the designs have been possible, but a lack of detector technology has resulted in few designs being considered for actual manufacturing. These designs are also difficult due to changes in the Abbe number in the different wavebands. Where the glass map is robust in the visible region, there exists a lack of crown glasses in the SWIR, and one is left with mostly flint glasses. This proves challenging from a chromatic perspective. The challenge becomes even more difficult if one wants to incorporate athermalization.

Induced aberrations in general are higher-order aberrations caused by ray perturbations of lower order, picked up surface by surface in the preceding optical system. [1], [2] Therefore, induced aberration coefficients are to some extent depending on the cumulative preexisting aberrations in the system. In the case of color aberrations, induced influences are already observable in the paraxial regime, since even paraxial rays are affected by dispersion. Hence, in every optical system small perturbations in ray heights and ray angles for paraxial rays of different wavelengths are present. These ray perturbations generate induced color aberration effects of higher-order. Here, the different orders refer to the paraxial ray dependency on dispersion. The linear or 1^st-order terms result in the well-known Seidel contributions of axial and lateral color, where any interaction of dispersion between different lenses is neglected. Starting at 2^nd-order terms, induced color effects are present. [3], [4] In this contribution, at first an introduction on the basic idea of induced color aberration is given. Following this, a surface resolved analytical description for axial and lateral color, distinguishing between induced and intrinsic parts, will be derived and discussed on a descriptive design example. Here especially the reversibility of raytrace direction is considered.

In my career as a lens designer, IODC lens design problems have been offering very important occasions. I would like to explain how I tackled the problems.

We discuss the behavior of air lenses in lens design. The structural aberration coefficients of a thin air lens are derived and compared with their glass thin lens counterpart. Examples are provided for a telephoto lens and the Monochromatic Quartet where air lenses or aspheric surfaces are used.

Longitudinal chromatic aberration (LCA) can limit the optical performance in refractive optical systems. Understanding a singlet’s chromatic change of effective focal leads to insights and methods to control LCA. Long established, first order theory, shows the chromatic change in focal length for a zero thickness lens is proportional to it's focal length divided by the lens V number or inverse dispersion. This work presents the derivation of an equation for a thick singlet's chromatic change in effective focal length as a function of center thickness, t, dispersion, V, index of refraction, n, and the Coddington shape factor, K. A plot of bending versus chromatic focal length variation is presented. Lens thickness does not influence chromatic variation of effective focal length for a convex plano or plano convex lens. A lens's center thickness'influence on chromatic focal length variation is more pronounced for lower indices of refraction.

The ray formalism is critical to understanding light propagation, yet current pedagogy relies on inadequate 2D representations. We present a system in which real light rays are visualized through an optical system by using a collimated laser bundle of light and a fog chamber. Implementation for remote and immersive access is enabled by leveraging a commercially available 3D viewer and gesture-based remote controlling of the tool via bi-directional communication over the Internet.

Four different methods for the fast robustness estimation of lens systems are presented and their values for two test cases with simple lens systems are calculated. These methods are evaluated in terms of computation time and their estimations are compared to the results of a Monte-Carlo analysis.

The spatial-temporal distribution of femtosecond pulses around the focal region of lenses has been extensively studied in recent years [1-6] due to the rapid progress in the technology of femtosecond lasers and their applications in many experiments in physics [7,8]. In this paper we present the time and spatial distribution of a few optical-cycle optical pulses around the focal region of a perfectly conducting spherical mirror which is a dispersionless system, by calculating the aberrations introduced when an off-axis collimated beam is incident on the mirror. The Seidel aberration theory has been used to calculate the wavefront aberration and the corresponding phase change for each frequency at the pupil of the mirror. The propagation of the beam from the exit pupil to the focal region is calculated by using the scalar diffraction theory [9]. The effect of aberrations in the focusing pulses has been analyzed in the literature by approximating the wavenumber of the pulse-frequencies by the wavenumber of the carrier frequency [4, 5]. In this paper we show that the monochromatic aberrations change the temporal duration of few-optical-cycle pulses when this approximation is removed. When this approximation is used, monochromatic aberrations do not introduce any temporal change in the focusing pulse even for pulses as short as 2.7fs@810nm which corresponds to a oneoptical-cycle pulse. Examples are presented for homogeneous and Gaussian illumination on the entrance pupil.

Different designs to generate optical vortex beams using metasurfaces at visible wavelength are numerically examined. Properties of the beams are studied at different polarization states.

This overview reflects the ISO working group activities of ISO/TC 172 Subcommittee 1 during the last years which have resulted in revisions and new ISO standards for optical components. For ISO 10110, ISO 14999 and other standards new surface forms and metrology techniques have been considered, standards about material characteristics have been consolidated, and optical drawings have been updated. Selected examples of new improvements and future work items are given.

An international effort to standardize IR optical materials has started with the development of standards for characterizing the materials (homogeneity, refractive index, striae, sampling, etc.). This paper will give an overview of these upcoming standards and their status.

The optics community has long recognized the problems of misinterpretation of the surface quality specification and the potential for conflict^1-2. Finally in 2017 there are new versions of the ISO and ANSI standards for surface imperfection tolerances which provide vastly improved alternatives to the existing options, especially the use of the US Military standard for specifying optical quality tolerances. This paper will review the existing standards in common use for specifying surface imperfections, and then describe in detail the new versions of the ISO and ANSI standards which are available in 2017. The details of the notations and inspection methods for each of the optics specifications will be provided, and the differences between the various alternatives will be discussed.

Design and manufacture of telescopic systems entails a significant degree of complexity. Such systems involve compounded optical systems and accessories for numerous applications. This manuscript provides an overview of ISO standardization activity for telescopic systems in ISO/TC 172/SC 4.

This paper concerns a numerical technique for evaluating effect of wave aberration on the frequency response of a laser Fizeau interferometer. The frequency response is described by Coherent Phase Transfer Function, which is defined as the Fourier transform of the phase of the complex image of a phase object formed by the interferometer normalized to the Fourier transform of the phase object itself. Based on the results of the study an aberration tolerance criterion of 1/8-wave P-V is proposed for the optical design of a laser Fizeau interferometer.

A standard way of tolerancing optical elements or systems is to perform a Monte Carlo based analysis within a common optical design software package. Although, different weightings and distributions are assumed they are all counting on statistics, which usually means several hundreds or thousands of systems for reliable results. Thus, employing these methods for small batch sizes is unreliable, especially when aspheric surfaces are involved. The huge database of asphericon was used to investigate the correlation between the given tolerance values and measured data sets. The resulting probability distributions of these measured data were analyzed aiming for a robust optical tolerancing process.

Wavefront deviation does not fully represent irregularity effects. It is shown how reflective telescopes with similar wavefront deviation provide very different optical performance leading to possible non-conformities not predicted by tolerance analyses.

Formula for a quick tolerance estimate of transmission variation in optical system with scanning pupil is developed. The estimate uses statistics of surface coating degradation due to random errors in layer thickness and refractive index. Example of using the tolerancing procedure on a sample optical system is presented and discussed.

The modeling and simulation of non-traditional imaging systems require holistic consideration of the end-to-end system. We demonstrate this approach through a tolerance analysis of a random scattering lensless imaging system.

We outline a method to tolerance imaging spectrometers using the cross-track, along-track, and spectral response functions of the system. This method offers a direct comparison of the expected performance relative to a standard set of metrics.

Nodal Aberration Theory, developed by Kevin Thompson and Roland Shack, predicts several important aberration phenomena but remains poorly understood. To de-mystify the theory, we describe the origins and fundamental concepts of the theory.

We address freeform aplanatic designs both as solutions of a differential system of equations and as limiting cases of SMS designs. We conclude that, in general, freeform aplanatic systems need at least 3 optical-surfaces with illustrative examples.

The large number of surface types that are manufacturable today provide many available paths to the optical designer. It is not always clear which path provides the optimal balance of merit function complexity, convergence speed, and image quality after optimization. This paper shows that Q-type polynomials provide a strong benefit in both convergence speed and image quality after optimization when the footprint comprises a large portion of the area inside the normalization radius, but for off-axis systems with large decenters this benefit is weakened. Also, the sensitivity of several unobscured reflective designs is compared to show that although surface types with more degrees of freedom can reduce some sensitivities, the design form is the primary driver and a system that occupies a smaller volume will tend to have higher sensitivities to misalignments regardless of surface type.

Orthogonal polynomials offer several mathematical properties for describing freeform optical surfaces. To leverage these properties, their interaction with variables such as tip and tilt, base sphere and conic variables, and packaging variables must be understood.

Optical systems that do not have axial symmetry can provide useful and unique solutions to certain imaging problems. However, the complexity of the optical design task grows as the degrees of symmetry are reduced and lost: there are more aberration terms to control, and achieving a sharp image over a wide field-of-view at fast optical speeds becomes challenging. Plane-symmetric optical systems represent a large family of practical non-axially symmetric systems that are simple enough to be easily described and thus are well understood. Design methodologies and aberration theory of plane-symmetric optical systems have been discussed in the literature, and various interesting solutions have been reported [1-4]. The little discussed in the literature technique of confocal systems is effective for the design of unsymmetrical optics. A confocal unsymmetrical system is constructed in such a way that there is sharp image along a given ray (called the optical axis ray (OAR)) surface after surface. It is possible to show that such a system can have a reduced number of field aberrations, and that the system will behave closer to an axially symmetric system [5-6]. In this paper, we review a methodology for the design of unsymmetrical optical systems. We utilize an aspherical/freeform surface constructed by superposition of a conic expressed in a coordinate system that is centered on the off-axis surface segment rather than centered on the axis of symmetry, and an XY polynomial. The conic part of the aspherical/freeform surface describes the base shape that is required to achieve stigmatic imaging surface after surface along the OAR. The XY polynomial adds a more refined shape description to the surface sag and provides effective degrees of freedom for higher-order aberration correction. This aspheric/freeform surface profile is able to best model the ideal reflective surface and to allow one to intelligently approach the optical design. Examples of two- and threemirror unobscured wide field-of-view reflective systems are provided to show how the methods and corresponding aspheric/freeform surface are applied. We also demonstrate how the method can be extended to design a monolithic freeform objective.

When symmetry is broken, the wave aberration function generalizes to have not just odd-orders, but also even-orders. Geometric interpretation of the lowest-order coefficients (i.e., second) and insights offered by consideration of these terms is presented.

The Functional Freeform Fitting (F⁴) method is utilized to design a freeform optic for oblique illumination of Mark Rothko’s Green on Blue (1956). Shown are preliminary results from an iterative freeform design process; from problem definition and specification development to surface fit, ray tracing results, and optimization. This method is applicable to both point and extended sources of various geometries.

This paper describes the use of freeform optical surfaces to control distortion to lower levels than achievable with rotationally symmetric polynomial aspheres. The magnitude of the improvement is illustrated using three different common reflective imager configurations.

Driven by the development of freeform four-mirror solutions, we compare analytical methods to generate starting point designs with various states of correction, surface types, symmetry, and obscuration. The advantages and disadvantages of each are examined.

The design of tilted, decentered, and non-rotationally symmetric or freeform optical systems has become an important part of optical design. We explore desensitization of traditional and freeform optical designs and compare their effectiveness.

Freeform NURBS surfaces improve the resolution of two wide angle reflective telescopes. The first is an extremely wide angle four mirror design covering 40° by 40° with a 1.4 Gpixel visible array, and the second is an earth observing telescope three mirror design with a 4° by 0.8° field of view.

We present a miniature camera lens design method that uses a freeform surface based on the pedal curve to the ellipse in polynomial form. Two designs are presented and their benefits of optical performance and tolerance sensitivity are compared to designs with conventional aspheric surfaces. We also reverse a freeform design using even aspherical surfaces to show that the optimization solution of a freeform design cannot be reproduced by even aspherical surfaces.

Given two points at opposite ends of a sequence of optical surfaces, simultaneously determine the points on each surface of the ray (i.e. path) that connects them. Computationally, this requires repeated solving of symmetric tridiagonal or banded-diagonal matrix equations.

Our new Contrast Optimization technique allows for robust and efficient optimization on the system MTF at a given spatial frequency. The method minimizes the wavefront differences between pairs of rays separated by a pupil shift corresponding to the targeted spatial frequency, which maximizes the MTF. Further computational efficiency is achieved by using Gaussian Quadrature to determine the pattern of rays sampled. Examples are given to demonstrate the advantages of the technique.

Several designs are shown that are alternatives to Bernhard Schmidt’s largely unknown 1934 three lens corrector replacement for an aspheric plate in his famous telescope.

Capabilities of beam shaping with diffractive optics are substantially improved by a concept of crossed zones. We generalized the map transformation design of beam shapers by additional set of diffractive zone borders orthogonal to phase isolines. Application of nonlinear transformation to diffractive grooves profile, provided another method of building crossed-zones. Computer simulation results confirm feasibility and flexibility of the proposed approach.

We pose that there is enough information left to reconstruct Petzval lens design approach, and answer the question of how Joseph Petzval design his famous portrait objective.

The optical requirements of fully immersive head mounted AR devices are inherently determined by the human visual system. The etendue of the visual system is large. As a consequence, the requirements for fully immersive head-mounted AR devices exceeds almost any high end optical system. Two promising solutions to achieve the large etendue and their challenges are discussed. Head-mounted augmented reality devices have been developed for decades – mostly for application within aircrafts and in combination with a heavy and bulky helmet. The established head-up displays for applications within automotive vehicles typically utilize similar techniques. Recently, there is the vision of eyeglasses with included augmentation, offering a large field of view, and being unobtrusively all-day wearable. There seems to be no simple solution to reach the functional performance requirements. Known technical solutions paths seem to be a dead-end, and some seem to offer promising perspectives, however with severe limitations. As an alternative, unobtrusively all-day wearable devices with a significantly smaller field of view are already possible.

The optical design of a compact volumetric display for drivers is presented. The system displays a true volume image with realistic physical depth cues, such as focal accommodation, parallax and convergence. A large eyebox is achieved with a pupil expander. The windshield is used as the augmented reality combiner. A freeform windshield corrector is placed at the dashboard.

Afocal lenses are often one part of a more complex optical system and are widely used to couple two infinity corrected optical subsystems (typically with different apertures and fields of view) together. One major concern for such an application is the pupil mismatch between the subsystems which degrades the system performance by introducing resolution and illumination loss at the edge of the field. This issue becomes even more apparent in an afocal zoom system, where the pupil locations usually vary as a function of zoom position. In this paper, formulae and design examples are demonstrated for designing a novel type of afocal zoom system that has two discrete zoom positions with stationary and accessible real entrance and exit pupils. The variation of field of view, while maintaining image plane and pupil locations are achieved simultaneously with only one moving group. The design space was explored with a first order analysis to validate different design forms. Design examples are shown for the only two possible design forms that resulted.

An extensive design study was conducted to find the best optimal power distribution and stop location for a 7.5x afocal zoom lens that controls the pupil walk and pupil location through zoom. This afocal zoom lens is one of the three components in a VIS-SWIR high-resolution microscope for inspection of photonic chips. The microscope consists of an afocal zoom, a nine-element objective and a tube lens and has diffraction limited performance with zero vignetting. In this case, the required change in object (sample) size and resolution is achieved by the magnification change of the afocal component. This creates strict requirements for both the entrance and exit pupil locations of the afocal zoom to couple the two sides successfully. The first phase of the design study looked at conventional four group zoom lenses with positive groups in the front and back and the stop at a fixed location outside the lens but resulted in significant pupil walk. The second phase of the design study focused on several promising unconventional four-group power distribution designs with moving stops that minimized pupil walk and had an acceptable pupil location (as determined by the objective and tube lens).

Gabor’s 1941 catadioptric design can be modified to give much higher performance versions. Some designs are shown that are .999 NA in air over a wide field with diffraction-limited correction on a curved image.

A design study is conducted in the 3-12 μm wavelength band for an F/2.5, 15.2 degree full field of view, 66 mm focal length imaging system. A survey of preferred homogeneous materials and their chromatic properties which transmit over the full wavelength band is explored. A survey of GRIN materials is also explored, which includes zinc selenide zinc sulfide GRIN, and chalcogenide GRIN from NRL and Schott. GRIN is able to expand the infrared glass map which is otherwise relatively small. The design space is explored over three and four homogeneous elements as well as one GRIN and two homogeneous elements. The three element design with the addition of GRIN results in a better balance between the two bands and is nearly diffraction-limited. The three element design can be reduced to two GRIN elements which has comparable performance to the homogeneous three element design.

We fabricate a deformable elastomeric grating by soft lithography and add a fluid layer. Tunable diffraction output as a function of applied strain is modified by refraction through the fluid. Using a water layer, the diffraction angle is tuned from 37.8° to 33.1° with an applied strain of 18%. Experimental results are accurately described by the combined effects of diffraction by a deformable grating and refraction by a fluid with a curved surface.

Echelle spectroscopy is a mature technique that was introduced over 60 years ago. However, the process of determining all of the physical parameters of an echelle spectrometer, especially the main parameters of the echelle grating itself (the groove density, the blaze angle, and the grating’s size), is not easily found in the literature. This paper takes a systematic approach to the problem of designing an echelle spectrometer and develops a design cycle that starts with the main requirements of an echelle spectrometer: the wavelength range, the spectral resolution, and the geometrical optical throughput. It sorts all of the equations that relate the requirements to the physical parameters of the spectrometer, identifies the design parameters (those that are directly selected by the designer), and develops a tool that determines all of the physical parameters of an echelle spectrometer for any given set of requirements. The detailed description of the tool and real life examples are proprietary information of PerkinElmer. As a result, this paper covers a general description of the tool and provides hypothetical examples.

The correction of modern microscopic lenses is rarely described in literature. Here an outline of the basic methods of correction is given and a systematic approach to design various types of lenses is proposed.

We can move an entrance pupil of a zoom lens from on-axis to off-axis by decentering lens groups of a zoom lens. This decentering zoom lens makes an objective lens of a stereomicroscope small. As a result, we can develop a stereomicroscope with high magnification and high resolution.

We propose a compact directional optical receiver for free-space communications, where a microlens array and micro-optic structures selectively couple light from a narrow incidence angle into a thin slab waveguide and then to an edge-mounted detector. A small lateral translation of the lenslet array controls the coupled input angle, enabling the receiver to select the transmitter source direction. We present the optical design and simulation of a 10mm x 10mm aperture receiver using a 30μm thick silicon waveguide able to couple up to 2.5Gbps modulated input to a 10mm x 30μm wide detector.

The obtaining a large field for visual observation under a polarizing microscope is still a technological challenge. Objective is the most difficult element of the optical system. It should be clear in relation to the chromatic aberration, but also have an increased numerical aperture.

The design of illumination optics that use extended sources and freeform surfaces is relatively common. We show how these nonimaging optics can be better understood by using pinhole images. Numerous examples are used to illustrate.

In some applications, homogenization of a light beam in the spatial and angular dimensions is required. Known integrator schemes such as rod and fly’s eye integrators merely provide integration in one dimension, and do not work properly for strongly inhomogeneous beams. In this contribution, we investigate whether and how light mixing can be improved by a combination of two integrators with the help of an optical system.

There are advantages to using planar light guide (PLG) concentrators instead of Fresnel concentrators for glass building façade photovoltaic systems. This paper details the main components of a PLG concentrator and describes how the concentrator works. The design of a PLG concentrator is constrained by the limitations of the diamond turning process used to make the microlens array. These manufacturing limitations and their effects on the lens design and system performance are reviewed. We report on the design of a 25 × 100 mm planar light guide concentrator with a 50x geometric concentration and an 85.0-88.1% theoretical optical efficiency for use in building integrated photovoltaics.

The equations to calculate equal-power reflectivity of a sequential series of beam splitters is presented. Non-sequential optical design examples are offered for uniform illumination using diode lasers. Objects created using Boolean operators and Swept Surfaces can create objects capable of reflecting light into predefined elevation and azimuth angles. Analysis of the illumination patterns for the array are also presented.

Tens of blue diode lasers are focused onto a ceramic phosphor to create a high-brightness high-lumen output light engine. Illumination uniformity and scattering properties of the phosphor impact the efficiency of the system.

ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) is one of the three present candidates for the next ESA medium-class science mission (M4) to be launched in 2026. During its 3.5 years of scientific operations from L2 orbit, this mission will observe spectroscopically in the infrared (IR) a large population of known transiting planets in the neighbourhood of the Solar System. The aim is to enable a deep understanding of the physics and chemistry of these exoplanets. ARIEL is based on a 1-m class telescope ahead of a suite of instruments: two spectrometer channels covering the band 1.95 to 7.80 µm and four photometric channels (two wide and two narrow band) in the range 0.5 to 1.9 μm. The ARIEL optical design is conceived as a fore-module common afocal telescope that will feed the spectrometer and photometric channels. The telescope optical design is based on an eccentric pupil two-mirror classic Cassegrain configuration coupled to a tertiary paraboloidal mirror. An all-aluminum structure has been considered for the telescope layout, and a detailed tolerance analysis has been conducted to assess the telescope feasibility. This analysis has been done including the different parts of the realization and life of the instrument, from integration on-ground to in-flight stability during the scientific acquisitions. The primary mirror (M1) temperature will be monitored and finely tuned via an active thermal control system based on thermistors and heaters. The heaters will be switched on and off to maintain the M1 temperature within ±1K thanks to a proportional–integral–derivative (PID) controller.

The WFIRST Wide-Field Infrared Survey Telescope TMA optical design provides 0.28-sq° FOV at 0.11” pixel scale to the Wide Field Instrument, operating between 0.48-2.0μm, including a spectrograph mode (1.0-2.0μm.) An Integral Field Channel provides 2-D discrete spectroscopy at 0.15” and 0.3” sampling from 0.42-2.0μm.

WFIRST is one of NASA’s Decadal Survey Missions and is currently in Phase-A development. The optical design of the WFIRST Integral Field Channel (IFC), one of three main optical channels of WFIRST, is presented, and the evolution of the IFC channel since the Mission Concept Review (MCR, end of Pre-Phase A) is discussed. The IFC has two subchannels: Supernova (IFC-S) and Galaxy (IFC-G) channels, with Fields of View of 3”x4.5” and 4.2”x9” respectively, and ~R 100 spectral analysis over waveband 0.42–2.0 μm. The Phase-A IFC optical design meets image quality requirements over the field of view (FOV) while balancing cost and volume constraints.

Reflecting anastigmatic optical systems hold several inherent advantages over refracting equivalents; such as compactness, absence of color, high “refractive efficiency”, wide bandwidth, and size-scalability to enormous apertures. Such advantages have led to these systems becoming, increasingly since their first deliberate development in 1905, the “go-to” solution for various classes of optical design problem. This paper describes in broad terms the history of the development of this class of optical system, with an emphasis on the early history.

The FINESSE spectrometer design (0.45 to 5 μm at a resolution of greater than 80 at f/12) is placed in context by reviewing history of unit magnification relays and spectrometers. Related imaging spectrometers are also described.

The Zwicky Transient Facility (ZTF) will be a major upgrade to the 48” Schmidt Camera at Palomar Observatory, which was initially commissioned in 1948. Although the optical design for ZTF is a relatively small part of the project, system requirements placed special constraints on the optical design. This paper presents the optical design for ZTF as well as the system requirements that drove the optical design.

The PSF for astronomical telescopes and instruments depends not only on geometric wavefront aberrations, but also on those polarization aberrations from the polarization properties of reflecting and transmitting surfaces. The image plane irradiance distribution is the linear superposition of four PSF images: one for each of the two orthogonal polarizations and one for each of two cross-coupled polarization terms.

Front converters for the iPhone 6, from six different vendors, are examined in detail. Telephoto, wide angle, and fisheye converters are examined. System performance is measured, and the measured lens designs are presented. Great variety is found in both design type and performance; little correlation is found between performance and design type.

A small form-factor lens was designed for the purpose of portraiture photography, the size of which allows use within smartphone casing. The current general requirement of mobile cameras having good all-round performance results in a typical, familiar, many-element design. Such designs have little room for improvement, in terms of the available degrees of freedom and highly-demanding target metrics such as low f-number and wide field of view. However, the specific application of the current portraiture lens relaxed the requirement of an all-round high-performing lens, allowing improvement of certain aspects at the expense of others. With a main emphasis on reducing depth of field (DoF), the current design takes advantage of the simple geometrical relationship between DoF and pupil diameter. The system has a large aperture, while a reasonable f-number gives a relatively large focal length, requiring a catadioptric lens design with double ray path; hence, field of view is reduced. Compared to typical mobile lenses, the large diameter reduces depth of field by a factor of four.

This new type of very fast (F/0.95) camera can accommodate a 4k x 4k detector with a pupil size of 280 mm. The camera is fully achromatic and made of only 3 components: a mirror and 2 fused silica lenses. The 2 lenses (corrector and field flattener) are glued together. The camera offers better image quality than classical Schmidt or equivalent cameras and is much smaller and lighter. This camera was developed for the MOONS spectrograph. This type of camera can be used not only for spectroscopy but also for imaging, some applications are also described in this paper.

We present a tutorial approach to understanding the ancient process of stereo photography. A simple transformation of object space allows the complete recording and viewing system, typically independent functions with a non-optical step, to be represented as an equivalent first-order optical system.

Modern lenses offer high resolution and display a significant sensitivity to misalignment. Accurately detecting misalignment requires evaluation over the full field of view (FOV). We propose a method of utilizing commercial MTF test stations and custom software to measure, evaluate, and visualize the performance over this entire area. These techniques allow the detection and characterization of misaligned systems with greater accuracy than typical three or five field point MTF measurements.

This paper discusses the idea of a Digital Optical Twin (DOT) in the field of optical system assembly. Furthermore, steps required towards this goal concerning the digital representation of a physical system are presented.

NFIRAOS, the first-light adaptive optics system for the Thirty Meter Telescope (TMT), has a cooled optical enclosure at -30 deg C with an evacuated, double-pane window to allow light in. NFIRAOS has chosen a radiative baffle design between the windows to mitigate frosting of the outer window and to avoid convective turbulence on either window. Here, we present the design of the baffle and the non-sequential analysis showing sufficient radiation rejection.

We develop a method to determine volumetric scattering model parameter values based on measured BSDF characteristics. Example models often use Mie or Gegenbauer particles. The accuracy and flexibility of this approach are illustrated.

This work explores quick predictive methods for calculating potentially risky stresses in cemented doublets underdoing temperature change that agree well with finite element analysis. We also provide guidelines for avoiding stress concentrations.

Mounting aspheres is often challenging because of the higher sensitivity to decenter and tilt compared to spherical lenses. This paper first describes aspheric surface decenter and tilt error as per ISO 10110 standard. Then, the most common lens mounting and alignment method for aspheric lenses are discussed in detail. Finally, an innovative mounting method that uses surface contact mounting is presented. This auto-centering method uses the optical surfaces as mounting interfaces to provide a high level of centering accuracy for aspheric lenses. Centering measurement results for different aspheric lenses mounted using this method are also presented.

In 2007 Dr Khine et al published a paper where they presented a technique using thermoplastics and PDMS to create microfluidic patterns¹. Their technique involves printing a pattern in a polystyrene sheet using a laser printer. Once the pattern is transfer the polystyrene sheets they are heated to reduce their size. By printing the same pattern of the plastic sheets before heating, it is possible to control the height up to 80 μm and the width as thin as 65 μm^{1, 2}. This technique is attractive to be used in optical fabrication due to its versatility, low cost and fast prototyping. However, in order to fabricate optical systems, we will need to control the refractive index of PDMS to allow design of basic optical components like waveguides, beam splitter, or diffuse reflectors; or more complex structures like interferometers, optical microfluidic lab-on-chip, micro-lens arrays. Several techniques exist to control the refractive index for PDMS either by controlling the curing temperature, the ratio between the base and curing agent, or by curing using UV light^3-5. In this paper, we present the changes on refractive index by changing the curing temperature for different base/reaction agent ratios. We then apply these results to fabricate an optical component for a free-space optical cross-connect (OXC). Optical cross-connects are an important network element for constructing the next generation of optical networks, where provisioning (reconfiguration), scalability, and fast restoration will be needed^6-8. The main attraction of all-optical switching is that it enables routing of optical data signals without the need for conversion to electrical signals, and therefore, is independent of data rate and data protocols. We have proposed previously^{9, 11} a new approach for an OXC. Our architecture is a free-space 3-D while still using digital MEMS. Our system is based on the optical White cell¹², which consists of three spherical mirrors among which light can circulate. In Section II, we will briefly mention the basic characteristics of the binary White cell OXC configuration. Section III we will introduce the changes induced on curing PDMS, our SDD design and its fabrication for two different beam displacements. Finally, in Section IV, we will present the summary and conclusions of our work.

In Peru, as in almost all Latin America, precision optical industry is almost null. One reason is the scarcity of human and technological resources. But, a few years ago, a masters and diploma university program in optical engineering was started in our university: Pontificia Universidad Católica del Perú¹ (PUCP) in Lima. Also, an optical shop on precision optics was implemented. Some students were trained at CIO in Leon, Mexico. In order to motivate optical business startups in Peru we planned to show some possibilities of optical devices fabrication trough doing prototypes. So, we started doing a small reflective telescope for moon observation^{2, 3}, where mirror and ocular polishing and opto-mechanics had priority. Aluminum evaporation was included. Now, we do a new step developing a binocular, as we know, it never was made before in Peru. This work includes the binocular geometric optics and opto-mechanical designs, the ocular manufacturing, and the binocular characterization of an 8x35 binocular for amateur observation.

Tomographic imaging of large objects from an x-ray source require a 240 mm square scintillator that is imaged onto a 90 mm square CCD with <0.01% distortion. A large pellicle and internal folding mirror keep the optical elements and the CCD camera out of the x-ray beam path to minimize shielding requirements.

We report on the design of a refracting prism array for use in a computational lensless imaging system. The technique discussed enables creation of a refracting element that maximizes signal on a detector region. Examples of pseudo-random prism arrays for the generation of images are provided. The pseudo-random prism array is compared to a randomly oriented prism array and the advantages of the optimal scattering element are highlighted.

We propose a method of extending the depth of field (EDOF) of conventional lenses for a low cost iris recognition front-facing smartphone camera. Longitudinal chromatic aberration (LCA) can be induced in the lens by means of dual wavelength illumination. The EDOF region is then constructed from the sum of the adjacent depths of field from each wavelength illumination. The lens parameters can be found analytically with paraxial raytracing. The extended depth of field is dependant on the glass chosen and position of the near object point.

Computational imagers fundamentally enable new optical hardware through the use of both physical and algorithmic elements. We report on the creation of a static lensless computational imaging system enabled by this paradigm.