Anamorphic Lens Research Articles

3D Metrology Using One Camera with Rotating Anamorphic Lenses.

In this paper, a novel 3D metrology method using one camera with rotating anamorphic lenses is presented based on the characteristics of double optical centers for anamorphic imaging. When the anamorphic lens rotates -90° around its optical axis, the 3D data of the measured object can be reconstructed from the two anamorphic images captured before and after the anamorphic rotation. The anamorphic lens imaging model and a polynomial anamorphic distortion model are firstly proposed. Then, a 3D reconstruction model using one camera with rotating anamorphic lenses is presented. Experiments were carried out to validate the proposed method and evaluate its measurement accuracy. Compared with stereo vision, the main advantage of the proposed 3D metrology approach is the simplicity of point matching, which makes it suitable for developing compact sensors for fast 3D measurements, such as car navigation applications.

High-precision anamorphic lens calibration with 3D and 2D calibration targets.

This paper presents a high-precision camera calibration approach for anamorphic lenses. The distortion model for anamorphic lenses is substantially more sophisticated than the distortion model for spherical lenses for the adaption of cylindrical lenses in anamorphic lens attachments. Based on the anamorphic aberration theory and numerical experiments, a polynomial type distortion model is provided for anamorphic lenses, with which high-precision camera calibrations can be achieved using 3D calibration targets. 3D calibration targets are typically limited in size, unable to encompass the whole imaging field of anamorphic lenses. The calibration results using 3D calibration targets tend to be unstable with the increased number of distortion coefficients in the anamorphic distortion model. Thus, after the anamorphic lenses have been calibrated with 3D calibration targets, they are recalibrated with 2D calibration targets that may fill the anamorphic lenses' field of view, resulting in more dependable and exact calibration results. Two anamorphic lenses are calibrated with high precision at the end the paper, which proves the effectiveness of the proposed method.

Lens design for parallel cylindrical anamorphic attachments with finite object distance.

A lens design method for parallel cylindrical anamorphic attachments with finite object distance is provided, which includes paraxial lens design, thin lens design, and thick lens design. The paraxial lens data can be determined from geometric optics. The thin lens design adopts a total of 28 anamorphic aberrations. The anamorphic lens splitting method for each anamorphic lens module is also provided for anamorphic aberration balancing between anamorphic lens modules. With the proposed design method, an anamorphic attachment is designed and manufactured in this paper, which proves the feasibility of the method.

Design of a miniature anamorphic lens with a freeform front group and an aspheric rear group

We propose a miniature anamorphic lens design that records wide-screen videos on an ordinary CMOS format. The front group consists of two freeform lenses, which achieve different focal lengths in the two orthogonal directions and thus enable the anamorphic characteristics. The rear group is made of rotationally symmetric aspheric elements that relay the image on the sensor. The annularly stitched extreme-point-based polynomial surface description is proposed to control the extreme point position and the air clearance between elements in the optimization process. An optimization method based on surface upgrade and conversion is adopted in the design. The design result offers an anamorphic ratio of 1.33 and an f-number (f / #) of ∼2, with a field of view of 65.3 deg × 35 deg. The overall length of the lens is 9.5 mm, which shows an advantage for integration into pocket devices.

Anamorphic zoom lens based on rotating cylindrical lenses.

An anamorphic zoom lens is designed for altering the size and aspect ratio of a laser beam. The design is based on using a Galilean beam expander in which the optical elements consist of two rotating cylinders. The rotation of the cylinders allows the spherical and cylindrical powers of the rotating cylindrical lens to be altered in such a manner that the magnification is anamorphic. A simple anamorphic zoom lens based on rotating cylindrical lenses is designed and then implemented. Operation of the anamorphic lens demonstrates a 1 to 1 to 10 to 1 aspect ratio beam conversion.

Monte Carlo first-order design method for anamorphic cinema zoom lenses

Anamorphic zoom lenses, used extensively in the motion picture industry, pose a significant design challenge, combining the difficulties of designing a high-performance zoom lens with those of designing an anamorphic lens. As a result, considerable emphasis must be placed on the first-order configuration of the starting point design before interfacing with optical design software. A Monte Carlo search method is introduced for generating first-order designs of anamorphic zoom lenses based on two different configurations. The obtained designs possess valid zoom motions and ray trace successfully while satisfying a set of system specifications. This search method offers a time effective and illustrative way of exploring the global solution space of first-order designs for use as starting points on the way to a thick lens, color-corrected final design. The results of such a Monte Carlo search are presented for two types of anamorphic zoom configurations, and a design example is demonstrated.

Simulation Study on the Improvement of the Luminance and the Color Uniformities of Integrated Quantum-Dot Backlights for LCD Applications

A new optical structure of the quantum dot (QD)-based backlight in which the QD layer was integrated on the light guide plate (LGP) was proposed. The optical performances were studied by using optical simulation, especially from the viewpoint of brightness and color uniformities. A low-index layer was inserted between the LGP and the QD layer to maintain efficient light guiding in the LGP, and an anamorphic lens was put over the blue LED to control the light distribution in the LGP. The simulation results for the optimized structure showed that the luminance uniformity was more than 93% and that the spatial and the angular variations in the color coordinates were less than 0.01. The present study demonstrates that satisfactory luminance and color uniformities can be achieved from the integrated QD backlights via optimization of the light distribution in the LGP. The integrated structure may be helpful in reducing the number of optical components and the cost of backlights for liquid crystal display (LCD) applications.

Aurora Image Search With a Saliency-Weighted Region Network

On account of the remarkable performance of convolutional neural network (CNN) features for natural image searches, utilizing it for other images collected with the anamorphic lens has become a research hotspot. This article selects the aurora images generated from a circular fisheye lens as a typical example. By considering the imaging principle and geomagnetic information, a saliency-weighted region network (SWRN) is presented and introduced into the Mask R-CNN pipeline. Our SWRN selects salient regions with important semantic information and weights them both hierarchically and spatially. Hence, regions encompassing the search target are strengthened while uninformative regions are discarded, which benefits the suppression of background interference and reduction of computational complexity. In practice, by aggregating the outputs of SWRN with post-processing, a compact CNN feature is generated to represent the aurora image. Large-scale aurora image search experiments are conducted, and the results prove that our method performs better than the state-of-the-art methods on both accuracy and efficiency.

Camera calibration for anamorphic lenses with three-dimensional targets.

Anamorphic lenses, with different optical powers along the tangential plane and the sagittal plane, are calibrated in this paper. The imaging model for anamorphic lenses is introduced. Compared with the pinhole model, it has two more intrinsic parameters: the anamorphic distance and the anamorphic angle. The anamorphic lens has two optical centers: one is in the tangential plane and the other is in the sagittal plane. The distance between the two optical centers is the anamorphic distance. The anamorphic angle refers to the angle between the camera coordinates and the pixel coordinates in the CCD plane. Formulas determining the initial value of the anamorphic distance are provided. Two experiments are conducted for the anamorphic lens calibration. As a comparison, the anamorphic lens is calibrated using the anamorphic imaging model and the pinhole model, respectively. The calibration accuracy can be improved remarkably if the anamorphic imaging model is applied, and calibrated results for the anamorphic distance and the anamorphic angle are very stable for different positions of the calibration target, which shows the validity and effectiveness of the anamorphic imaging model for anamorphic lens calibration.

Paraxial lens design of anamorphic lenses with double telecentricity

A systematic approach for paraxial design of anamorphic lenses with double telecentricity is provided. Six types of anamorphic lens systems with double telecentricity are discussed. For available lens types, formulas defining the interval distances between lens components, the object position, the stop position, and the anamorphic ratio are derived. Illustrating figures and examples are also provided. If the telecentric zoom attachment is place behind the stop, the magnification of the whole lens system can be changed continuously, and a fixed distance between the object and the image can be guaranteed during zooming. The paraxial lens design method for the rear telecentric zoom attachment is also provided.

Co-optimization method to reduce the pattern distortion caused by polarization aberration in anamorphic EUV lithography

Extreme ultraviolet lithography is regarded as the most attractive technology to achieve 7 nm node and below. A new high-numerical-aperture anamorphic objective lens is designed to extend the single exposure resolution limit. However, the polarization aberrations (PAs) induced by the multilayer coatings on mirrors cause pattern distortions that cannot be neglected. In this paper, a source, mask, and process parameter co-optimization method is developed to compensate for the pattern distortions caused by PAs and increase the process window (PW). We first present an asymmetric source represented by the superposition of Zernike polynomials to reduce the pattern placement error (PPE). Then, a weighted cost function that incorporates the influences of PAs is innovated. Finally, a gradient-based statistical optimization method is adopted to minimize the cost function by optimizing the lithography system parameters alternately. Simulations at the 7 nm node of the 1D mask pattern indicate that for the system with a PA of marginal field, compared with our earlier work, the critical dimension error and PPE of the proposed method are reduced by 75.0% and 82.4%, respectively, and the PW is increased by 97.4%.

Paraxial lens design of anamorphic lenses with a fixed anamorphic ratio

If the stop lies on the right of the anamorphic lenses, the entrance pupils in the tangential plane and the sagittal plane might not coincide with each other. In this condition, the anamorphic ratio will change according to the position of the object, which is not preferred in filming and machine vision. In view of this, a systematic approach for the paraxial design of anamorphic lenses with common entrance pupils is provided. Two basic types of anamorphic attachment are presented: basic anamorphic attachment and basic anamorphic zoom attachment. The anamorphic ratio can be changed by changing the interval distances between lens components if anamorphic zoom attachments are adopted. Formulas defining the interval distances between lens elements, the object position, the stop position, and the anamorphic ratio are derived. Illustrating figures and examples are also provided for each lens type.

Thin lens aberrations for anamorphic lenses.

This paper provided thin lens aberrations for anamorphic lenses, including the central thin lens aberrations, the central Lagrange invariant shift, the central conjugate shift, and the central pupil shift. Based on thin lens theory and the paraxial lens module, the aberration of the anamorphic lens system can be easily corrected. The central Lagrange invariant shift can be used for aberration correction for an anamorphic zoom lens system. In order to make a concise expression for the central conjugate shift, eight aberration coefficients are introduced: D¯3x, D¯5x, D¯6x, D¯10x, D¯11y, D¯12x, D¯15x, and D¯16y. Similarly, four aberration coefficients are introduced for the central pupil shift: D11x, D¯11x, D16x, and D¯16x. A simulation is conducted that proves numerically the validity of the thin lens aberrations for an anamorphic lens system.

Age Effects on Visuo-Haptic Length Discrimination: Evidence for Optimal Integration of Senses in Senior Adults

Demographic changes in most developed societies have fostered research on functional aging. While cognitive changes have been characterized elaborately, understanding of perceptual aging lacks behind. We investigated age effects on the mechanisms of how multiple sources of sensory information are merged into a common percept. We studied visuo-haptic integration in a length discrimination task. Atotal of 24 young (20-25 years) and 27 senior (69-77 years) adults compared standard stimuli to appropriate sets of comparison stimuli. Standard stimuli were explored under visual, haptic, or visuo-haptic conditions. The task procedure allowed introducing an intersensory conflict by anamorphic lenses. Comparison stimuli were exclusively explored haptically. We derived psychometric functions for each condition, determining points of subjective equality and discrimination thresholds. We notably evaluated visuo-haptic perception by different models of multisensory processing, i.e., the Maximum-Likelihood-Estimate model of optimal cue integration, a suboptimal integration model, and a cue switching model. Our results support robust visuo-haptic integration across the adult lifespan. We found suboptimal weighted averaging of sensory sources in young adults, however, senior adults exploited differential sensory reliabilities more efficiently to optimize thresholds. Indeed, evaluation of the MLE model indicates that young adults underweighted visual cues by more than 30%; in contrast, visual weights of senior adults deviated only by about 3% from predictions. We suggest that close to optimal multisensory integration might contribute to successful compensation for age-related sensory losses and provides a critical resource. Differentiation between multisensory integration during healthy aging and age-related pathological challenges on the sensory systems awaits further exploration.

Seeing with a Filmmaker’s Eyes: Glimpses of Mobilized Landscapes in Stan Brakhage’s The Wonder Ring (1955) and Visions in Meditation #2: Mesa Verde (1989)

In this paper I present various ways in which Stan Brakhage’s The Wonder Ring (1955) and Visions in Meditation #2: Mesa Verde (1989) tend to challenge the concept of American landscape by means of cinematic conventions traditionally associated with phantom rides, city symphonies and contemporary road movies. It seems that Brakhage’s works do not only employ non-standard editing, camera movement and extended shot to reproduce a continuous flow of motion, but they also exploit the dynamics between the spectactor’s “mobilized virtual gaze” (Friedberg, Window 2) and passing views by evoking a distorted experience of sensational and meditative voyages, hence questioning panoramic perception and an idealized image of American (film) landscape intrinsically bound with the natural and technological sublime. Particularly, both films draw on rapid handheld camerawork, superimpositions, anamorphic lens, bright or dim exposures, fades, odd angles, softened focus and other techniques to defamiliarize and objectify the protagonist’s journey and thus document Brakhage’s perception and extra-objective reality.

Fisheye lens camera based surveillance system for wide field of view monitoring

This paper presents a fisheye lens camera based surveillance system for wide area monitoring. The proposed system consists of: (i) digital anamorphic transformation, (ii) two layer panorama generation, and (iii) geometric transform invariant object detection and tracking for the fisheye camera based system. Since peripheral regions of acquired images are not used in the fisheye lens based imaging system, the proposed algorithm transforms a circular fisheye lens image into an anamorphic image using directional interpolation to maximize the usage of lost regions. In detecting and tracking objects, the proposed algorithm adopts a region based approach to provide robust feature points and object shapes against to various tracking challenges including geometric transformation, sub sampling, interpolation, and dynamic illumination. Experimental results demonstrate that the proposed method can successfully detect and track moving objects in the very wide field of view without using multiple cameras or an optical anamorphic lens

광기구적 자동 비열화가 적용된 비정형 적외선 광각 카메라

A system of infrared camera optics with wide field of view and anamorphic lenses is proposed, and its validity verified through manufacture. The infrared camera produced provides a wide field of view of over 100 degrees in the horizontal direction, and an even greater magnification in the vertical direction. As a result, the system can have a wider surveillance range and improved detection ability at the same time. In addition, a new optomechanical automatic athermalization mechanism is proposed and applied to the infrared camera. Its performance and utility is proved through testing. Keywords: Infrared optics, Anamorphic lens, AthermalizationOCIS codes: (110.3080) Infrared imaging; (220.3620) Lens system design; (280.4788) Optical sensing and sensing

Beam shaping system based on a prism array for improving the throughput of a dispersive spectrometer.

A beam shaping system (BSS) for improving the throughput of a dispersive spectrometer is presented by employing two anamorphic lenses and a prism array to segment the beam. The BSS was designed based on the inverse method of beam shaping for laser diode bars and the means of an optical slicer. In an experiment, a BSS was set up so that the incident light of a neon lamp with a circular spot from an input fiber was transformed into an elliptical spot coupled into a slit of a spectrometer without a change of divergence. Spectral measurement results demonstrate that the throughput of the dispersive spectrometer was doubled without loss of spectral resolution. The BSS can be combined with the existing dispersive spectrometer to improve the luminous flux and signal-to-noise ratio.

Alternative Entrances: Phillip Noyce and Sydney’s Counterculture

[Extract] Phillip Noyce is one of Australia's most prominent film makers - a successful feature film director with both iconic Australian narratives and many a Hollywood blockbuster under his belt. Still, his beginnings were quite humble and far from his role today when he grew up in the midst of the counterculture of the late sixties. Millions of young people his age joined the various 'movements' of the day after experiences that changed their lives-mostly music but also drugs or fashion. The counterculture was a turbulent time in Sydney artistic circles as elsewhere. Everything looked possible, you simply had to "Do It!" - and Noyce did. He dived head-on into these times and with a voracious appetite for its many aspects-film, theatre, rallies, music, art and politics in general. In fact he often was the driving force behind such activities.

Aspherical anamorphic lens for shaping laser diode beam

We propose a novel method to fabricate aspherical anamorphic lenses at very low costs. A droplet made of UV-curable negative photoresist is placed on an asymmetrical substrate and cured when its surface shape evolves to be aspherical due to electrostatic force and meets the designed optimal shape. Both numerical analysis and experimental results are presented, showing that the fabricated lens has different optical powers in the two transverse directions and can collimate the divergent beam generated by a laser diode in the fast-axis direction with high energy efficiency.