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This paper described an off-axis five-mirror-anastigmatic telescope. It is composed of three aspheric surfaces and one spherical surface while the third mirror and fifth mirror have the same parameters at the same place. This configuration is useful for having wide field of view. The strip full field of view for the near infrared telescope is 20°×0.2°. The entrance pupil is located in front of the first mirror. There is an intermediate image between the second mirror and the third mirror. The entrance pupil diameter is 100 mm and the effective focal length is 250 mm. The spectral range is 0.85-1.75 μm. The pixel pitch is 15 μm. The image quality is near the diffraction limit. Some methods were used to restrain the stray light such as a field stop near the intermediate image, the baffle, the narrow-band pass filter and a stop in front of the focal plane.

Aiming at importance of atmospheric transport model in the collectivity design of ground target observation remote sensor, based on analysis of PcModtran application feasibility, amend geometrical model of remote sensor design is presented, then discussed the calculation of PcModtran for energy transmittivity of all kinds of pollutants atmospheric in detect path, all kinds of radiance in entrance pupil radiance of remote sensor by emulation instance, probed into the method that applying PcModtran filtering function analyze photoelectrons number of radiance on the focal face of detector, foundation that verify collectivity design index of satelliteborne optical remote sensor is presented. Successful application in some type secondary satellite, it verified the method is of guidance function on the collectivity design.

In order to adapt to small size and low cost space platform such as mini-satellites, this paper studies the design of optics for compact star sensor. At first, the relationship between limiting magnitude and optical system specifications which includes field of view and entrance pupil diameter is analyzed, based on its Pyramid identification algorithm and signal-to-noise ratio requirement. The specifications corresponding to different limiting magnitude can be obtained after the detector is selected, and both of the complexity of optical lens and the size of baffle can be estimated. Then the range of the limiting magnitude can be determined for the miniaturization of the optical system. Taking STAR1000 CMOS detector as an example, the compact design of the optical system can be realized when the limiting magnitude is in the interval of 4.9Mv~5.5Mv. At last, the lens and baffle of a CMOS compact star sensor is optimally designed, of which length and weight is respectively 124 millimeters and 300 grams.

Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.

The theoretical basis for the mirror high-aperture optical system synthesis, based on the properties of the reflecting surface accepted as the base having a shape of a paraboloid of rotation are considered in the work Design parameters and residual aberrations tables of the few design solutions for considered optical systems are presented. From the analysis of aberration correction of the image formed by the considered optical system, it follows that the angular value image space is limited, primarily, the image surface curvature. To compensate for curvature of the image surface can be applied Smith lens. The additional condition that determines a high aperture ratio of the optical system of the considered lens as a whole was introduced, but it complicates the process of correcting the aberrations of a wide beam of rays. It is shown that the use of afocal Mersenne system with known anaberration properties, allows you to build a series of compact and SLR mirror-lens systems with aplanatic, anastigmatic and plananastigmatic aberration correction formed the image, at the same time the length of the system is about four times smaller than the diameter of its entrance pupil. Importantly, when applying the lens for using in a long wavelength range emission, the requirements for aberration correction image formed by the lens are reduced, and accordingly, manufacturability are increases.

In our previous publications, we had successfully made a deflectometry measurement by using a portable laser projector. In this research, we propose the beam weighting centroid method rather than previous the phase shifting method for quantification of the angular direction of the testing beam in the tested optics entrance pupil. By projecting the angular sequential lines on tested optics entrance pupil, the wavefront aberration is reconstructed from two orthogonal directions measurements, in a similar way to the line scanning deflectometry. The limited gray scale problem of laser projector during the phase shifting measurement is therefore eliminated. The reconstructed wavefront is proven to yield a more accurate result than the phase shifting methods at the cost of more image frames and acquisition time.

DAM (Discretized Aperture Mapping) is an original optical concept able to improve the performance in high angular resolution and high contrast imaging by the present class of large telescopes equipped with adaptive optics. By discretizing the entrance pupil of a large telescope into an array of many coherent sub-apertures, DAM provides unique imaging and filtering properties by means of spatial filtering and interferometric techniques. DAM can be achieved by means of single-mode fibers, integrated optic waveguides, pinholes, or simply with an innovative BIGRE optical device. BIGRE is formed of an afocal double micro-lenses array. In addition to the pupil discretization process by spatial filtering, BIGRE can also provide two other optical processes: the pupil densification or the pupil dilution. DAD (Discretized Aperture Densification) increase the sub-aperture sizes and is suitable to a hypertelescope, whereas DADI (Discretized Aperture Dilution Interferometry) reduces the sub-aperture sizes and turns a large telescope into a Fizeau interferometer. This paper deals with the first in-lab experiment at visible wavelength of BIGRE devices for the three configurations above. We study the point spread function (PSF) when observing a point-like object located either on-axis or at various off-axis positions across the field of view. Both interferometric and diffractive effects are described. The experimental measurements are in good agreement with the BIGRE theory. It results that BIGRE fulfils the requirements to carry out spatially filtered pupil discretization (DAM), with possible densification (DAD) or dilution (DADI).

GRAPE is the polarimeter planned to be installed on the main Cassegrain focus of GTC (Gran Telescopio Canarias), having an equivalent entrance pupil of 10.4 m, located at the Observatorio del Roque de los Muchachos (ORM) , in La Palma, Canary Islands. It’s meant to deliver full Stokes (IQUV) polarimetry covering the spectral range 0.420-1.6 μ, in order to feed the HORS instrument (High Optical Resolution Spectrograph), mounted on the Nasmyth platform, which has a FWHM resolving power of about 25,000 (5 pixel) designed for the wavelength range of 380-800 nm. Two calcite blocks and a BK-7 prism arranged in a Foster configuration are splitting the O12.5mm collimated beam into the ordinary and extraordinary components. The entire subunit from the Foster prisms down to the input fibers is rotated by steps of 45 degrees in order to retrieve Q, U components. By inserting a quarter wave retarder plate before the entrance to the Foster unit circular polarization is measured too. The current paper consist of two main parts: at first CFD simulations are introduced, which have been run compliant to the specifications derived by the environmental conditions and the transient thermal gradients taking into account the presence of the electronic cabinets installed, which are triggering the boundary conditions for the outer structure of the instrument; then a thermal control model is proposed based on heat exchangers to stabilize the inner temperature when compensation via passive insulation is not enough. The tools that have been adopted to reach for such goal are Ansys Multiphysics, in particular CFX package and Python scripts.

The SNIFS CALibration Apparatus (SCALA), a device to calibrate the Supernova Integral Field Spectrograph on the University Hawaii 2.2m telescope, was developed and installed in Spring 2014. SCALA produces an artificial planet with a diameter of 1° and a constant surface brightness. The wavelength of the beam can be tuned between 3200 A and 10000 A and has a bandwidth of 35 A. The amount of light injected into the telescope is monitored with NIST calibrated photodiodes. SCALA was upgraded in 2015 with a mask installed at the entrance pupil of the UH88 telescope, ensuring that the illumination of the telescope by stars is similar to that of SCALA. With this setup, a first calibration run was performed in conjunction with the spectrophotometric observations of standard stars. We present first estimates for the expected systematic uncertainties of the in-situ calibration and discuss the results of tests that examine the influence of stray light produced in the optics.

The German telescope eROSITA will be the first X-ray instrument orbiting around the L-2 lagrangian point. Therefore, modelling the radiation environment in that region of space and its interaction with the instrument is particularly important, as no measured data of other X-ray detectors can be used as a reference to predict how the space conditions will impact the instrumental capabilities. The orbit around L-2 extends well beyond the Earth's magnetosphere, where the flux of galactic cosmic particles is cut by the geomagnetic field, and fluxes of energetic particles one order of magnitude higher than in low Earth orbits are expected. Furthermore, as experienced by Chandra and XMM-Newton, softer protons may be scattered through the mirror shells and funneled to the focal plane, representing a potential additional source of background. To investigate and assess this component we are developing a ray tracing simulator for protons, that follows the track of each proton from the entrance pupil down to the focal plane. In this paper we report on an updated version of the code that allows to propagate protons in both the polar and azimuthal directions in elastic regime.

MWIR imaging spectrometer is promising in detecting spectral signature of high temperature object such as jet steam, guided missile and explosive gas. This paper introduces an optical design of a MWIR imaging spectrometer with a cold slit sharply reducing the stray radiation from exterior environment and interior structure. The spectrometer is composed of a slit, a spherical prism as disperser, two concentric spheres and a correction lens. It has a real entrance pupil to match the objective and for setting the infrared cold shield near the slit and a real exit pupil to match the cold shield of the focal plane array (FPA). There are two cooled parts, one includes the aperture stop and slit, and the other is the exit pupil and the FPA with two specially positioned cooled shields. A detailed stray radiation analysis is represented which demonstrates the outstanding effect of this system in background radiation restraint.

In this paper, we propose a multi-fields direct design method aiming to calculate two freeform surfaces with an entrance pupil incorporated for wide field of view on-axis line imaging applications. Both infinite and finite conjugate objectives can be designed with this approach. Since a wide angle imaging system requires more than few discrete perfect imaging points, the multi-fields design approach is based on partial coupling of multiple fields, which guarantees a much more balanced imaging performance over the full field of view. The optical path lengths (OPLs) and image points of numerous off-axis fields are calculated during the procedure, thus very few initial parameters are needed. The procedure to calculate such a freeform lens is explained in detail. We have designed an exemplary monochromatic single lens to demonstrate the functionality of the design method. A rotationally symmetric counterpart following the same specifications is compared in terms of RMS spot radius to demonstrate the clear benefit that freeform lens brings to on-axis line imaging systems. In addition, a practical achromatic wide angle objective is designed by combining our multi-fields design method with classic optical design strategies, serving as a very good starting point for further optimization in a commercial optical design program. The results from the perspective of aberrations plots and MTF values show a very good and well balanced performance over the full field of view.

The paper is targeted to find the optimal mathematical model and the calibration algorithm for the industrial endoscope equipped with the prism-based attachable stereo adapter, which allows imaging from two different points by a single sensor. We consider the conventional calibration methods for the pinhole camera model with polynomial distortion approximation and compared them with the ray tracing model based on the vector form of Snell’s law. In order to evaluate each of the proposed models we have developed the software for the imitation of various calibration procedures using different types of calibration targets. We use the computer simulation to prove that the pinhole camera models, widely used in machine vision, are very limited for describing prism-based endoscopic measurement systems. Our analysis identified the main problems for these models, such as entrance pupil shift, non-homocentric beams and required number of coefficients for polynomial models and the iterative forward ray aiming for the ray-tracing model. The proposed technique is flexible and can also be used to test stability and convergence of the parameter estimation procedures and to compare calibration targets and strategies.

The goal was to revisit an important, yet unproven notion that accommodative microfluctuations facilitate the determination of direction (sign) of abrupt focus changes in the stimulus to accommodation. We contaminated the potential temporal cues from natural accommodative microfluctuations by presenting uncorrelated external (screen) temporal defocus noise that combined with the retinal image effects of natural microfluctuations. A polychromatic Maltese spoke pattern thus either modulated defocus at a combination of two temporal frequencies (on-screen noise condition) or was static (control condition). The on-screen conditions were combined with step changes in optical vergence that were randomized in direction and magnitude. Five subjects monocularly viewed stimuli through a Badal optical system in a Maxwellian view. An artificial 4-mm aperture was imaged at the entrance pupil of the eye. Wavefront aberrations were measured dynamically at 50 Hz using a custom Shack-Hartmann aberrometer. Dynamic changes in the Zernike defocus term with step changes in optical vergence were analyzed. We calculated the percentage of correct directional responses for 1, 2, and 3 D accommodative and disaccommodative step stimuli using preset criteria for latency, velocity, and persistence of the response. The on-screen noise condition reduced the percent-correct responses compared to the static stimulus, suggesting that this manipulation affected the detectability of the sign of the accommodative stimulus. Several possible reasons and implications of this result are discussed.

This study investigated the generation method and properties of a super-Rayleigh speckle field that had a contrast value greater than 1. First, an exponential factor was added to the complex amplitude of the Rayleigh speckle, and then, its inverse Fourier-transformed phase matrix was applied to a spatial light modulator (SLM). As the collimated light beam illuminated the SLM, the super-Rayleigh speckle field was formed at the SLM’s Fourier plane. The effects of the exponential factor, size of the macro-pixel of the SLM, and diameter of the entrance pupil on the contrast values of the super-Rayleigh speckle patterns were investigated. Especially, the influence of different macro-pixel sizes of the SLM was systematically studied. Moreover, the stability region of the super-Rayleigh speckle field was examined. The experimental results showed that the contrast values of the super-Rayleigh speckle field increased exponentially as the exponential factor increased under the same conditions. In addition, the contrast values increased as the size of the macro-pixel or diameter of the entrance pupil increased. Furthermore, as the pupil diameter increased, the width of the stability region decreased according to a negative quadratic index that corresponded to the longitudinal length of a single speckle.

We present a geometric model of image formation in Scheimpflug cameras that is most general. Scheimpflug imaging is commonly used is scientific and medical imaging either to increase the depth of field of the imager or to focus on tilted object surfaces. Existing Scheimpflug imaging models do not take into account the effect of pupil magnification (i.e. the ratio of the exit pupil diameter to the entrance pupil diameter), which we have found to affect the type of distortions experienced by the image-field upon lens rotations. In this work, we have also derived the relationship between the object, lens and sensor planes in Scheimpflug configuration, which is very similar in form with the standard Gaussian imaging equation, but applicable for imaging systems in which the lens plane and the sensor plane are arbitrarily oriented with respect to each other. Since the conventional rigid camera, in which the sensor and lens planes are constrained to be parallel to each other, is a special case of the Scheimpflug camera, our model also applies to imaging with conventional cameras.

Adjustment and control of the illumination pupil asymmetry is relevant for wafer alignment and overlay of lithography tools. Pupil asymmetries can cause a tilt in aerial image (Aerial Image Tilt, or AIT). This AIT, combined with a focus offset, leads to a horizontal image shift. Pupil asymmetries can be related to a shift of the entire illumination pupil (geometrical telecentricity) caused by illuminator misalign. Another type of pupil asymmetry is energetic imbalance (quantified by pupil Center of Gravity, COG). The scanner can show pupil variation across the exposure slit. In general the COG at the edge of the slit is often worse than in the center part of the slit. Recently, ASML has released the NXT:1980Di that is equipped with an enhanced illuminator to improve pupil COG variation across the slit. In this paper we explore the performance of this scanner system and show that the AIT variation across the slit is also reduced significantly.

The current augmented-view device for glaucoma patients are limited by the low angle minification (less than 3X), image overlapping and pupil mismatching. We present a novel ultra-thin near-eye augmented-view device (UNAD) with a proper minification angle of 4X to avoid scanning eye movements. The device is realized by one symmetrical ultra-thin off-axis eight-mirror reversed telescopic optical system (field-of-view (FOV): x:-34°~3°; y: -5°~-20°, 5°~20°) and one central un-minified optical system (FOV: -5°~5°), and hence, the system can achieve a FOV (x:-34°~3°; y: -20°~20°) without overlapping images. Furthermore, the device fully accounts for pupil matching with the entrance pupil of the human eye. Finally, the simulation results in CODE V and LightTools verify that our proposed system is feasible and has potential practical value for glaucoma patients.

Including an entrance pupil in optical systems provides clear benefits for balancing the overall performance of freeform and/or rotationally symmetric imaging systems. Current existing direct design methods that are based on perfect imaging of few discrete ray bundles are not well suited for wide field of view systems. In this paper, a three-dimensional multi-fields direct design approach is proposed to balance the full field imaging performance of a two-surface freeform lens. The optical path lengths and image points of numerous fields are calculated during the procedures, wherefore very few initial parameters are needed in advance. Design examples of a barcode scanner lens as well as a line imaging objective are introduced to demonstrate the effectiveness of this method. (C) 2015 Optical Society of America

According to the radiation intensity of the spaced-target, the SNR and detection distance of the spaced target of visible light has been study and analyzed. The relationship between SNR, detection distance and the size of the spaced-target, the reflectance, observed phase angle, as well as the entrance pupil area has been obtained. The specific formula of the detection distance of the spaced-target of detection of the visible light detection system is given. And key indicators that impact the detection distance of spaced target of visible light have been analyzed. The study provides a theoretical basis for the performance of the future space-target detection system.

A common entrance pupil optical system is designed for simultaneously acquiring the distance information and the visible texture by a 32×32 APD array sensor together with a 512×512 CCD. The optical system can be used for real-time color 3D Flash Ladar acquisition, aiming the same target area, for real-time 3D modelling and visualization.

The paper presents a new simulation model for the efficient simulation of EUV pellicles. Different pellicle stacks, pellicle deformations and particles on the pellicle can be considered. The model is based on properly designed pupil filters representing all pellicle and particle properties to be investigated. The filters are combined with an adapted image simulation. Due to the double transition of the EUV light through the pellicle, two different models for the pupil filter computation have been developed: A model for the forward light propagation from the source to the mask and a model for the backward light propagation from the mask to the entrance pupil of the system. Furthermore, for the accurate representation of particles on the pellicle, a model has been developed, which is able to combine the different size dimensions of particles, of the entrance pupil and of the illumination source. Finally, some specific assumptions on the light propagation make the pellicle model independent from the illumination source and speed up the simulations significantly without introducing an important error. Typically, the consideration of a pellicle increases the overall image simulation time only by a few seconds on a standard personal computer. Furthermore, a simulation study on the printing impact of pellicles on lithographic performance data of a high NA anamorphic EUV system is presented. Typical illumination conditions, a typical mask stack and different mask line features are considered in the study. The general impact of a pellicle as well as the impact of pellicle transmission variations, of pellicle deformations and of particles on the pellicle on typical lithographic performance criteria is investigated.

The Colour and Stereo Surface Imaging System (CaSSIS) is the high-resolution scientific imager on board the European Space Agency’s (ESA) ExoMars Trace Gas Orbiter (TGO) which was launched on 14th March 2016 to Mars. CaSSIS will observe the Martian surface from an altitude of 400 km with an optical system based on a modified TMA telescope (Three Mirrors Anastigmatic configuration) with a 4th powered folding mirror. The camera EPD (Entrance Pupil Diameter) is 135 mm, and the expected focal length is 880 mm, giving an F# 6.5 in the wavelength range of 400- 1100 nm with a distortion designed to be less than 2%. CaSSIS will operate in a “push-frame” mode with a monolithic Filter Strip Assembly (FSA) produced by Optics Balzers Jena GmbH selecting 4 colour bands and integrated on the focal plane by Leonardo-Finmeccanica SpA (under TAS-I responsibility). The detector is a spare of the Simbio-Sys detector of the Italian Space Agency (ASI), developed by Raytheon Vision Systems. It is a 2kx2k hybrid Si-PIN array with a 10 μm pixel pitch. A scale of 4.6 m/px from the nominal orbit is foreseen to produce frames of 9.4 km × 47 km on the Martian surface. The University of Bern was in charge of the full instrument integration as well as the characterization of the focal plane and calibration of the entire instrument. The paper will present an overview of the CaSSIS telescope and FPA optical performance. The preliminary results of on-ground calibration and the first commissioning campaign (April 2016) will be described.

We present a simple technique for synthesizing an infinite depth of field image from a sequence of photographs captured while rotating a symmetric lens about the center of the entrance pupil. We discuss the feasibility conditions and provide a Zemax simulation that verifies the method.

An off-axis four-mirror-anastigmatic telescope is presented here which is composed of two aspheric surfaces and two spherical surfaces. The entrance pupil diameter is 290 mm and the stop is located at the primary mirror. The effective focal length is 900 mm. The strip field of view for the telescope is 15° × 0.2° and if the telescope is launched into an orbit about 400 km altitude, the observed range width will be more than 105 km within a scene without any other auxiliary scanning instrument. The spectral range can be as wide as from visual wave band to infrared wave band in the mirror system. This telescope can be used for environmental monitoring with different detectors whose pixel is adapted to the optical resolution. In this paper, the spectral range is chosen as 3.0 -5.0 μm, and center distance of the pixel is 30 μm. And the image quality is near the diffraction limit.

The radiometry of quasi-homogeneous sources is derived from the theory of partial coherence by using properties of the Wigner definition function. Suggested is the linear-system approach to the process of forming an optical image in which the convolution operator is used twice. First to describe influence of aberrations of an optical system on the image quality. Second to describe influence of the radiation pattern of the source-object and the form and the size of the entrance pupil on the fall-off of the irradiance from centre of the image plane to its edge.

Based on research of the traditional phase-shifting profilometry (PSP) method, a tilted measurement system is proposed. The proposed technology makes three constraints of the traditional phase-shifting profilometry measurement system less constrains. The exit pupil of the projecting system and the entrance pupil of the CCD imaging system are not horizontal and not placed at equal height. The optical axis in the CCD imaging system is not necessarily perpendicular with a specific tilting angle to the reference plane. The optical axises of the CCD imaging system and projecting system are not coplanar. The two axises do not intersect with each other. Compared to the traditional phase-shifting profilometry the proposed method offers a flexible way to calculate height distribution.

Dome A is the highest point on the Antarctic Plateau, and the Chinese Expedition Team first arrived here in 2005 January. It is an excellent site for astronomical observations. The first-generation Chinese Antarctic optical telescope CSTAR has been operating on Dome A since 2008 January. The second-generation Chinese telescopes known as the Three Antarctic Survey Telescopes (AST3) are currently being developed. AST3 includes three telescopes matched respectively with G-, R- and I-band filters. Each telescope is a catadioptric optical telescope with an entrance pupil diameter of 500 mm, an f-ratio of 3.73 and a field of view of 414. The optical system of the AST3 consists of a transparent aspherical plate, an aspherical primary mirror and a spherical refractive corrector with a filter before the focal plane. The main features of the AST3 are the following: good image quality, a planar focal plane, reduced atmospheric dispersion, an absence of distortion and a compact structure. The main scientific goal of the AST3 is to survey the sky. In 2012 January, the first telescope of the AST3 was successfully installed on Dome A.

The sparse aperture system is a novel solution to design larger telescope of high angular resolution by utilizing several small sub-apertures to displace the full aperture. The system is of light weight and low cost. Multiple-mirror telescope (MMT) is one type of sparse aperture systems. We have analyzed the Golay3 MMT with a spherical primary mirror to obtain the relationships between the sub-mirrors on the primary mirror and the shapes of sub-apertures on the entrance pupil with different relative aperture by investigating the entrance pupil characteristics. The maximum fill factor and the maximal overlay factor were derived, and the tangency condition when sub-mirrors of the Golay3 MMT are tangency was also given out. The expressions of the point spread function (PSF) and the modulation transfer function (MTF) of the Golay3 MMT were deduced. The characteristics of both the PSF and the MTF were obtained based on the deduced formulas and Matlab simulating patterns. Two Cassegrain telescopes of a spherical primary mirror with the Golay3 configuration and with an aspherical secondary mirror were designed. Based on the relationships between the fill factor and the overlay factor, the optimal parameters of sub-mirrors on the primary mirror were selected. The PSFs and MTFs of Cassegrain telescopes with the Golay3 MMT were designed by Zemax simulation. The simulation results are consistent with the theoretical results.

The depth-of-field (DOF) of an imaging system is closely related to the pupil function that describes the characteristics of the pupil such as size and shape. Shallow DOF is especially problematic in microscopic optical imaging systems because they have relatively large aperture size for high optical resolution. In this paper, a new DOF extension method is proposed. This is to acquire an image by integrating the incoming light while changing the size of annular pupil. By dividing the pupil into annular form, the effect of the defocus aberration is reduced. Theoretical background is explained and simulation and experimental results are shown for verification. The results show that the DOF can effectively be extended by this method.

This paper presents the results of experimental studies of staring infrared photodetector arrays (PDAs) designed for use in object recognition systems. A special bench was developed to determine the threshold sensitivity of PDAs to spot irradiation, i.e., the minimum excess of the signal power over the background with allowance for the measuring path and its performance. Estimations were made of the root-mean-square (RMS) noise of the PDA element which determines the detection threshold of the excess of the radiation power of an object over the background in the plane of the entrance pupil.

Aiming at importance of atmospheric transport model in the collectivity design of ground target observation remote sensor, based on analysis of PcModtran application feasibility, amend geometrical model of remote sensor design is presented, then discussed the calculation of PcModtran for energy transmittivity of all kinds of pollutants atmospheric in detect path, all kinds of radiance in entrance pupil radiance of remote sensor by emulation instance, probed into the method that applying PcModtran filtering function analyze photoelectrons number of radiance on the focal face of detector, foundation that verify collectivity design index of satelliteborne optical remote sensor is presented. Successful application in some type secondary satellite, it verified the method is of guidance function on the collectivity design.

Radial distortion for ordinary (non-fisheye) camera lenses has traditionally been modeled as an infinite series function of radial location of an image pixel from the image center. While there has been enough empirical evidence to show that such a model is accurate and sufficient for radial distortion calibration, there has not been much analysis on the geometric/physical understanding of radial distortion from a camera calibration perspective. In this paper, we show using a thick-lens imaging model, that the variation of entrance pupil location as a function of incident image ray angle is directly responsible for radial distortion in captured images. Thus, unlike as proposed in the current state-of-the-art in camera calibration, radial distortion and entrance pupil movement are equivalent and need not be modeled together. By modeling only entrance pupil motion instead of radial distortion, we achieve two main benefits, first, we obtain comparable if not better pixel re-projection error than traditional methods, second, and more importantly, we directly back-project a radially distorted image pixel along the true image ray which formed it. Using a thick-lens setting, we show that such a back-projection is more accurate than the two-step method of undistorting an image pixel and then back-projecting it. We have applied this calibration method to the problem of generative depth-from-focus using focal stack to get accurate depth estimates.

A convolution is proposed to describe the influence of the source–object distribution and entrance pupil of an optical system on the fall-off of the irradiance from centre of the image plane to its edge.

Purpose TO evaluate spherical aberration and through-focus optical performances of 5 presbyopia-correcting and 2 monofocal intraocular lenses (IOLs). Setting Flaum Eye Institute, University of Rochester, Rochester, New York, USA. Design Experimental study. Methods Five presbyopia-correcting IOLs (Restor +4D SN6AD3, Restor +3D SN6AD1, Rezoom NXG1, Tecnis multifocal ZM900, Crystalens HD500) were tested using an optical bench system consisting of a model eye, a high-resolution Hartmann-Shack wavefront sensor, and an image-capturing device. Two monofocal IOLs (Sofport AO LI60AOV, Acrysof SN60AT) were measured for comparison. No accommodation was simulated. The spherical aberration profiles of each IOL were measured using the wavefront sensor. Through-focus performance was evaluated by calculating cross-correlation coefficients and comparing the likenesses of captured images of a resolution target and a perfect reference image. Results With a 5.0 mm entrance pupil, the SN6AD3, SN6AD1, ZM900, NXG1, and HD500 IOLs had spherical aberration of −0.18 μm, −0.14 μm, −0.15 μm, −0.07 μm, and −0.01 μm, respectively. Distance image quality was poorer with multifocal and accommodating IOLs than with monofocal IOLs. All multifocal IOLs had effective distance and near image quality but had a loss in intermediate image quality. The HD 500 accommodating IOL had decreased distance image quality and slightly increased depth of focus compared with the monofocal IOLs because of the bispheric design. Conclusions The presbyopia-correcting IOLs had different optical characteristics, including spherical aberration profile and through-focus performance. An accurate understanding of the optical characteristics of individual IOLs is essential to selecting the best presbyopia-correcting IOL and thus improving cataract surgery outcomes. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Citation information: Ehsaei A, Chisholm CM, Mallen EAH & Pacey IE. The effect of instrument alignment on peripheral refraction measurements by automated optometer. Ophthalmic Physiol Opt 2011, 31, 413–420. doi: 10.1111/j.1475-1313.2011.00838.x Abstract Purpose: Interest in peripheral refraction measurement has grown in recent years in response to the insight it may provide into myopia development. In light of the likely increase in the clinical use of open-field autorefractors for peripheral refraction measurements, the question of instrument alignment and its impact on the accuracy of refraction measurements is raised. The aim of this study was to investigate the accuracy and precision when an open-field device was moved away from alignment with the corneal reflex towards the pupil margins, and to determine the optimum alignment position for peripheral refraction measurements. Methods: Autorefractions were performed on the right eyes of 10 healthy participants using the Shin-Nippon NVision-K 5001 autorefractor. At least five measurements were taken with the subject fixating a distance target in the primary position of gaze, and then four peripheral fixation targets located along the horizontal meridian (10° and 20° eccentricities in the nasal and temporal retina). Measurements were taken at seven alignment positions across the pupil for each fixation angle. Refraction was recorded as the spherical and cylindrical power. Results: The central objective refraction achieved under cycloplegia based on the autorefraction result for the whole sample, ranged between −5.62 D and +1.85 D for the value of sphere, with a maximum astigmatism of −1.00 D. Acceptable alignment position range varied with fixation angle but was −1.0 to +1.0 mm in width across the pupil. Peripheral refraction measurements centred on the entrance pupil were as reliable as those centred on the corneal reflex. Conclusions: Our data suggest that for peripheral refraction measurements, there is a range of acceptable positions and operators can be confident of the validity of results obtained if aligned half way between the pupil centre and corneal reflex. The alignment becomes more critical at greater eccentricities.

Radiation pressure is not the only source of scattering force in the focal region of a microscope objective. Depending on the numerical aperture and the polarization characteristics of the light at the entrance pupil, the force emerging from the spin density may represent a fundamental contribution to the total force experienced by small (Rayleigh) particles when using high resolution objectives. The predicted and experimentally observed strong asymmetry of the trapping potential for linear polarization is shown to be related to non-conservative spin curl forces. We demonstrate the characteristics of this force field when using linear polarized light with circular and annular pupils and in the radial and azimuthal polarization structures.

We analyze aberrations in an optical laser printer system in order to know how to determine an allowable non-uniformity of the movement of a light spot, how to determine allowed variation of spot sizes, and how to minimize the influence of these deviations on technological errors. In this paper, the correction and the tolerance of distortion are analyzed by using the concept of zonal and global distortions. The tolerance of field curvature is also obtained from Gaussian beam properties. In order to reduce the change of the entrance pupil position and to make a more compact laser printer system the minimum size of the rotator is exactly derived from the geometry with the introduction of the shift angle of the input beam.

In this work, we report a model for accurately calculating the focal volumes corresponding to astigmatic elliptical beams used in fs-laser waveguide writing. The model is based on the use of the ABCD matrix formalism for the propagation of a Gaussian beam. The code includes the effects of propagation on the astigmatic elliptical beam, and the effects of beam truncation and diffraction at the entrance pupil of the focusing objective due to beam clipping when overfilling the pupil. The results predict that for a given astigmatism value and propagation distance it is possible to efficiently suppress the astigmatic focus closer to the surface. This explains previous experimental results where single structure waveguides with controllable aspect-ratio were fabricated using astigmatic-elliptical beams. Furthermore, we investigate the respective roles of astigmatism and beam propagation, as well as the strong impact of truncation and diffraction effects caused by clipping the beam at the pupil of the focusing optics. Finally, based on the results from our model, we present some practical considerations in terms of beam propagation and phase wrapping constraints. © Springer-Verlag 2011., This work was partially supported by the Spanish Ministry of Science and Innovation under TEC2008-01183 project. A.R. acknowledges a I3P-CSIC postdoctoral contract (co-funded by the European Social Fund). A.F. acknowledges a grant under Project TEC 2006-04538.

According to the 30.4 nm radiation properties of the earth's plasmasphere,an earth's plasmaspheric extreme ultraviolet imaging method based on the moon was researched for the first time.The technical parameters of the extreme ultraviolet imager used in the lunar surface were determined,and its field of view is 15°,angular resolution is 0.1° and the entrance pupil area is larger than 70 cm2.By combining a single spherical multilayer mirror and a spherical microchannel plate photon counting imaging detector,the extrame ultraviolet imager was designed.The ray tracing of designed extreme ultraviolet imager with multilayer optics was also performed.Results show that the radii of the blur spots are 0.210,0.204,0.204,and 0.207 mm respectively at 0,3,5,and 7.5°,which are basically identical at different field of views.In woking on the lunar surface,the imager has a vision scope of 15.0 RE to cover the main body of the earth's plasmasphere and a spatial resolution of 0.10 RE that can reveal the main details of the earth's plasmasphere.It provides a high quality imaging method for the observation of earths plasmasphere.

Based on the Extended Nijboer-Zernike theory,the effect of different amplitudes for exit pupils on the image intensity in the focal plane was analyzed.A novel approach was applied to testing the wavefront according to the actual condition of the amplitude in the exit pupil,which can help eliminating the error caused by the nonuniformity illuminated pupil and the Fast Fourier Transform in the original phase retrieval algorithms.A testing experiment was performed on an imaging optical system,and obtained results show that the tested wave fronts in the exit pupil of a camera lens are 0.196 5λ in PV and 0.022 4λ in RMS(the testing wavelength λ is 632.8 nm).The aberrations in the wavefront are mainly astigmatism,coma and high order astigmatism.Furthermore,the approach can also be used to analyze the amplitude in the exit pupil of a camera lens and calculate the light intensity distribution on other focal planes.The experiment proves this approach available.

The calibration of an imaging spectrometer by using the diffuser method should consider not only the accuracy of calibration instruments,but also the effects of instrument and geometric parameters from the imaging spectrometer on calibration results.According to the calibration principle of imaging spectrometer using the diffuser method,this paper deduces the expression of the collected signal electron number in each spectral channel of the imaging spectrometer by taking the parameters as self-variables, and it analyzes the effects of the incident angle of standard lamp,the distance of standard lamp to the diffuser,the slit direction and the observation incident angle of the imaging spectrometer on the electron number collected by the detector pixels.The results show that when the F number is set to be 3 and 4,the entrance pupil in 0.1-0.2 m,the standard lamp illuminating angle less than 12° and the distance of the standard lamp in 0.5-2 m,the change of the signal electron number can be less than 1%.It satisfies the accuracy need of the calibration by using the diffuser method.

A mechanical design of a fast wide-field telescope with an entrance pupil that is 180 mm diameter, a focal length of 294 mm, and an angular field of view of 10° is described. Original construction solutions have been found for this type of system.

Here a flexible optical geometry of Fourier Transform Profilometry (FTP) is discussed, and a strict theoretical analysis about an improved phase-height mapping formula based on a new description of a reference fringe and a deformed fringe proposed based on a general case, in which the exit pupil of the projecting lens and the entrance pupil of the imaging lens are not horizontal and do not have the equal distance to the reference plane; moreover, the optical axes of the projecting device and of the imaging device are not coplanar. Compared with the traditional Fourier Transform Profilometry, it is easier for us to obtain the full-field fringe through adjusting the location of either the projector or the imaging device. Compared with the Improved Fourier Transform Profilometry (IFTP), only three length system parameters need to be measured, so the operation is simple and the result is more reliable.

System assessment for design often involves averages, such as the standard deviation of the wavefront error, which are estimated by ray tracing through a sample of points within the entrance pupil. 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% to 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 cubature schemes relevant to optical design of systems with circular pupils.

Purpose: To evaluate the effects of ablation decentration on the induction of higher order wavefront aberrations (HOAs) in active eye-tracker–assisted myopic photorefractive keratectomy (PRK) using the VISX STAR S4 laser with ActiveTrak (Abbott Medical Optics [AMO]). Methods: Ninety-four myopic eyes (53 patients) were divided into three groups according to ablation decentration (group 1, ≤0.15 mm, 20 eyes; group 2, >0.15 to ≤0.30 mm, 54 eyes; and group 3, >0.30 mm, 20 eyes). The distances of ablation centers from the centers of the entrance pupils were analyzed using corneal topography. Wavefront errors were measured preoperatively and at 6 months after PRK using a VISX WaveScan aberrometer (AMO). Statistical analysis was performed to assess the influence of ablation decentration on PRK-induced HOAs. Results: The mean decentration was 0.23±0.10 mm (range: 0.04 to 0.52 7mm). The magnitude of all HOAs was significantly increased at 6 months postoperatively ( P P P =.015), coma ( P =.038), and spherical aberration ( P =.038), and group 2 versus group 3 for coma ( P =.049). Conclusions: Ablation decentration >0.30 mm from the center of the entrance pupil was associated with greater induction of total HOA, coma, and spherical aberration after PRK, as compared with ablation decentration

The phase structure is investigated at the focal plane of an aplanatic, high numerical aperture focusing optical system. The tightly focused field is numerically evaluated using combination of the Richards–Wolf approach and the Stratton–Chu diffraction integral. An investigation is performed for both 2D and 3D geometries for a number of different illumination structures, having piecewise quasi-constant phase at the entrance pupil and different polarization states. For the investigated illumination structures, the quadratic phase term of the focused field was found to depend on the structure of the incident illumination contrary to the paraxial case where it depends solely on the optical system parameters.