Pupil Field Research Articles

Bisymmetric pupil modification deconvolution strategy for differential optical transfer function (dOTF) wavefront sensing

Context. The differential optical transfer function (dOTF) is a model-independent image-based wavefront sensor for measuring the complex pupil field (phase and amplitude). This method is particularly suitable for compensating non-common path aberrations or for the phasing of segmented telescopes that often prevent the so-called diffraction-limit resolution from being achieved with real-world instruments. Aims. The main problem inherent to the dOTF approach is to address the effect of the convolution. The resolution of the recovered complex pupil field is impacted by the size of the pupil modification. The complex pupil field estimated by the dOTF is blurred by convolution with the complex conjugate of the pupil modification. If the pupil modification involves a non-negligible region of the pupil (actuator or segment poke), it causes significant blurring and resolution loss. Methods. We propose a bisymmetric pupil modification deconvolution strategy to solve this problem. We use two different dOTFs with the opposite-sign pupil modification to identify the pupil modification location and four dOTFs with a symmetric pupil modification to complete the knowledge of their impact on the complex pupil field prior to the deconvolution process in the Fourier domain. The proposed strategy solves the intrinsic limitation of a former deconvolution algorithm, namely the cross-iteration deconvolution algorithm, which is restricted to amplitude pupil modification and precludes its applicability to phase pupil modification. Results. The bissymetric pupil modification deconvolution strategy is a novel probing pattern that permits the extension of iterative cross-deconvolution to phase-only probes. The effectiveness of the proposed approach has been validated analytically and with numerical simulations. Conclusions. The bisymmetric pupil modification deconvolution strategy can improve the resolution and accuracy of dOTF wavefront sensing and contributes to efficient and precise image-based wavefront sensing techniques.

Młodzież o posiadanych umiejętnościach prospołecznych

Social competence determines the appropriate socialization and acquiring maturity essential to handle the social roles effectively. The article focuses on the adolescents’ prosocial abilities used by them in relations with others. The aim of the research was to find out the level of prosocial competence proclaimed by the adolescents. The results showed skills which young people use effectively in social interactions and those which they lack. The data established the difference in the declared abilities depending on the sex and allowed to outline the typical profile of a girl and boy. It might be a valuable clue while working on the prevention directions in the field of pupils’ hazardous behavior. Key words: social competence, nurture, hazardous behaviour, prevention, resocialization.

Inverse Design of Focused Vector Beams for Mode Excitation in Optical Nanoantennas

We propose a free-space, inverse design of nanostructure's effective mode-matching fields via a backward propagation of tightly focused vector beams to the pupil plane of an aplanatic system of high numerical aperture. First, we study the nanostructure's eigenmodes without considering any excitation fields and then extract the modal near fields in the focal plane. Each modal field is then taken as the desired focal field, the band-limited waves of which are backward propagated to the pupil plane via a reversal of the Richards--Wolf vector diffraction formula. The pupil fields can be designed to be genuinely paraxial by associating the longitudinal electric/magnetic field component with the radial one on the reference sphere. The inversely designed pupil field in turn is propagated forwardly into the focal region to generate the designed focal field, whose distribution over the nanostructure's surface is used to evaluate the overlap between the designed focal field and the modal fields, i.e., the modal expansion coefficients. Studies for a silicon nanodisk monomer, dimer, and tetramer demonstrate the ability of our inverse approach to design the necessary tightly focused vector field that can effectively and exclusively match a certain eigenmode of interest. Compared with the forward beam-shaping method, the inverse design approach tends to yield quantitatively more precise mode-matching field profiles. This work can have a significant impact on optical applications that rely on controllable and tunable mode excitation and light scattering.

Pachydermoperiostosis: A Rare Masquerader of Acromegaly and Thyroid Acropachy

Background: Pachydermoperiostoasis is a rare disease of prostaglandin metabolism that presents with extensive clubbing, skin thickening, and enlargement of hands and feet, often misdiagnosed as acromegaly or thyroid acropachy. Clinical Case: A 29-year-old male presented with progressive enlargement of hands and feet for the past three years, with increased sweating, seborrhea, acne, arthralgia, and photophobia. On examination, facial furrowing and severe clubbing in all fingers and toes was noticed, with palmoplantar hyperhidrosis, tenderness and widening around distal forearms, and increased heel pad thickness. He had nodulocystic acne, injected right eye with ptosis, normal pupil, and visual field. Slit-lamp examination showed extensive pannus formation, with yellow nodules, suggestive of phlyctenular conjunctivitis, secondary to a systemic inflammatory process. No prominent supraorbital ridge, prognathism, proptosis, goiter, or pretibial myxedema. No family history of a similar condition. Labs showed normal cell counts and metabolic panel. Normal IGF-1 (112 ng/mL, n 84-250 ng/ml), TSH (3.82 mIU/L, n 0.27-4.2 mIU/L), fT4 (1.19 ng/dL, n 0.93-1.7 ng/dL), Testosterone (354 ng/dL, n 249-836 ng/dL) and Prolactin (15.2 ng/mL, n 2.1-17.7 ng/mL). Inflammatory markers were elevated with ESR of 54 mm/hr (n 0-15 mm/hr) and CRP of 12.45 mg/L (n 1-4 mg/L). ANA, RF, anti-CCP, and HLA-B27 were negative. C3 and C4 levels were normal as well. Interferon-gamma release assay was negative. Imaging showed a normal chest X-ray. Brain MRI showed normal pituitary gland and increased scalp skin thickness with cutis verticis gyrata “undulating skin sign.” X-ray of hands and feet showed diffuse periosteal reaction. A diagnosis of pachydermoperiostosis (PDP) was made based on clinical criteria (thickened skin, periosteal reaction, and finger clubbing). PDP is a genetic disorder of prostaglandin metabolism with variable expression and incomplete penetrance. It manifests after puberty and affects males more than females with a 7:1 ratio. PDP has been recently shown to go through an inflammatory phase, in which patients may benefit from immunosuppressants or NSAIDs. PDP should be distinguished from hypertrophic pulmonary osteoarthropathy, thyroid acropachy, and acromegaly. Our patient had a normal chest radiograph and normal hormone levels (TSH, T4, and IGF-1). The patient received topical steroids and antibiotics with artificial tears for his eyes, which resulted in a good response, and was referred to a rheumatology clinic for further management. Clinical Lesson: PDP can be mistaken for acromegaly or thyroid acropachy and should be considered in any patient with acromegaloid features with normal IGF-1 and no evident pituitary pathology. Awareness of this condition can help in reaching the diagnosis promptly.

Digital adaptive optics based on digital lateral shearing of the computed pupil field for point scanning retinal swept source OCT

A novel non-iterative digital adaptive optics technique is presented in which the wavefront error is calculated using the phase difference between the pupil field and its digital copies translated by a pixel along the horizontal and vertical direction in the pupil plane. This method provides slope data per pixel, thus can generate > 50k local slope data samples for a circular pupil of diameter 256 pixels with high accuracy and dynamic range. It offers more than 12x faster computational speed in comparison to the sub-aperture based digital adaptive optics method. Furthermore, it is independent of any system parameters, the light distribution in the pupil plane, or the intensity of the image. The technique is useful in applications such as interferometric or digital holography based microscopy, metrology, and as digital wavefront sensor in adaptive optics, where focusing of light in the sample is involved that creates a guide star or where the sample itself exhibits guide star-like structures. This technique is implemented in a point scanning swept-source OCT at 1060 nm, and a large wavefront error with a peak to valley of 20 radians and root mean square error of 0.71 waves is detected and corrected in case of a micro-beads phantom sample. Also, human photoreceptor images are recovered from aberrated retinal OCT volumes acquired at eccentricities of 2 and 2.5 degrees from the fovea in vivo.

Dynamical generation of multiple focal spot pairs with controllable position and polarization

We report a flexible method to dynamically generate multiple sub-wavelength focal spot pairs with adjustable polarization, position and number at the focal plane of a high numerical aperture (NA) objective lens. The desired incident field on the pupil plane can be analytically derived by employing the time-reversed method combined with the dipole antenna radiation theory. The numerical simulations of the corresponding tightly focused field are conducted using the Richards-Wolf vectorial diffraction theory. The validity of the presented method is demonstrated through experimental generation of several designed pupil fields with a versatile vectorial optical field generator and characterization of the produced focused fields with Stokes parameter measurements.

Demonstration of lateral resolution enhancement by focusing amplitude modulated radially polarized light in a confocal imaging system

Lateral resolution enhancement is demonstrated in a confocal imaging system with amplitude-modulated radially polarized (RP) light at the wavelength Annular pupil fields and optimized amplitude distribution functions can be realized with a spatial light modulator. By comparing images obtained with full and amplitude modulated apertures of RP illuminations using a high numerical aperture (NA = 0.9), spatial resolution of has been achieved experimentally. This result agrees very well with theoretical simulation results and will be helpful in improving performance of the non-fluorescent imaging systems.

Elementary school teacher’s pedagogical work of health direction

The development of the Ukrainian democratic state requires the creation of a qualitatively new national education system in order to ensure revival of intellectual and spiritual potential of the Ukrainian people. Teacher’s personality formation in this aspect is a complex multifaceted process. Education is one of the main problems of theory and practice of pedagogical education. Pedagogical activity in the field of pupils’ physical education is a specific form of activity aimed at the realization by elementary school teacher as constructive, communicative, organizational and cognitive functions of his professional activity. Elementary school teacher’s pedagogical work is characterized by a variety of professional responsibilities, which every teacher must be able to perform in a qualified manner. It demands from a teacher of high focus on the qualitative solution of pedagogical tasks (improving, educational, and educative) in physical education of pupils and also ethical communication with pupils, colleagues on service, parents of pupils. Pedagogical work of physical culture teacher at elementary school in consists in ability to realize aims, to unleash tasks on physical education of pupils. General and aged tasks of physical education are highlighted. General tasks of physical education, such as "strengthening of pupils’ health", "versatile physical development" "hardening of pupils" pass through the whole process of physical education from the 1st to the 4th grade. Pedagogical technology of elementary school teacher reflects tactics of implementation for educational technologies, is based on knowledge of the regularities of functioning the system "teacher - environment - student" in certain conditions of study (individual, group, collective, mass, etc.). Common features and patterns of implementation for the educational process regardless of the specific educational discipline is inherent it. A teacher turns into a public figure responsible for each student during all years of his work at school, having realized the main directions of professional work - study, upbringing and development of pupils, ensuring diverse physical development of a child.

Switchable pupil expansion propagation using orthogonal superposition varied-line-spacing H-PDLC gratings in a holographic waveguide system.

To solve the problem of small field of view in traditional holographic waveguides, this paper proposes a waveguide-coupling technique using orthogonal superposition varied-line-spacing (VLS) gratings. These gratings expand the x and y directions and orthogonally superimpose to achieve transmission in a waveguide and enlarge the pupil field of view. At the optical coupling input end and the coupling output end of a waveguide, one-dimensional VLS gratings are used to realize horizontal expansion of the image. Then a vertical VLS grating is orthogonally superimposed at the exit end to realize vertical expansion of the image. Finally, the waveguide transmission and expansion of the image are completed. In the experiment, holographic polymer dispersed liquid crystal one-dimensional VLS gratings in the x and y directions are fabricated and coupled with a waveguide. An image source with a diameter of 0.5cm is waveguide-transferred and coupled out, and then passed through the vertical grating. Amplification is performed to obtain an expanded image of a diameter of 2.28cm. In this study, the diffraction characteristics of the grating used to realize pupil expansion in the holographic waveguide system are analyzed and simulated. It is calculated that the diffraction efficiency of the VLS gratings can reach 80% or more in the 532nm band. Additionally, the characteristics of an electronically controlled switch are studied. Experimental results show that the method can be used for expanding the field of view and can be applied to waveguide systems for image transmission and expansion.

Challenges to detect glaucomatous visual field loss with pupil perimetry.

We evaluated the pattern deviation of pupil fields to differentiate a glaucomatous damage using the head-mounted perimeter “imo”. Thirty-four eyes of 26 glaucoma patients (mean age, 55.1 years) were examined. The pattern deviation (85th percentile) of pupil fields was calculated from the difference between age-matched normal and abnormal percentage pupil constriction. Consequently, glaucomatous damages were remarkably distinguished from the normal pupil fields using the pattern deviation of the imo.

Diffraction-limited optical focusing with arbitrarily oriented magnetic field

In this paper, an approach to create diffraction-limited optical focal spots with arbitrarily oriented magnetic dipolar field components in 4Pi microscopy configuration is proposed. This is achieved by focusing two counter-propagating modulated vector beams consisting of complex intensity and polarization distribution. Through combining the magnetic dipole radiation pattern and the Richards–Wolf vectorial diffraction method, the required illuminations at the pupil plane of a 4Pi focusing configuration for the reconstruction of magnetic dipole focal field are found analytically. Furthermore, the orientation of the doughnut shape focal field can be rotated arbitrarily by modulating the pupil field distribution carefully. As an extension, a three-dimensional optical bubble encloses a transverse spin magnetic field can be obtained by introducing a second magnetic dipole oriented in the orthogonal plane with appropriate amplitude and phase differences.

Evaluation of Pupil Fields Using a Newly Developed Perimeter in Glaucoma Patients

ABSTRACTPurpose: To evaluate objective pupil fields using a newly developed perimeter for the detection of glaucomatous damage.Materials and Methods: Forty-three eyes of 32 glaucoma patients (42–69 years) were examined. Glaucomatous eyes were classified into three stages using the Hodapp–Anderson–Parrish grading scale (early, 16; moderate, 14; and severe, 13 eyes). The head-mounted perimeter “imo” was used to measure the percentage pupil constriction (PPC) of the pupil fields at 36 test points. A stimulus target size of Goldmann V with 0 decibels (dB) light under 31.4 apostilbs (asb) background was presented. Visual fields were measured with the Humphrey Field Analyzer 10–2 program. Using the 3D OCT-2000, 10 × 10 grid of the macular thickness were also obtained. Median correlation coefficients (r) of each examined eye were analyzed between the PPC and visual field sensitivity (dB), and the thickness of the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL)+ (GCL + inner plexiform layer [IPL]), and GCL++ (RNFL + GCL + IPL), respectively.Results: Moderate correlations between the PPC and dB (r = 0.44–0.55), and GCL++ (r = 0.43–0.45) were obtained in the correspondence analysis of 12 test points. There were no significant differences in glaucoma severity (P = 0.924–1.000). However, some patients with extremely early stage glaucoma (visual field index ≥90%) tended to have poor correlation.Conclusions: Pupil fields of the imo generally corresponded to the visual fields and the RNFL + GCL + IPL thickness, even in early glaucoma; however, the examiner must clearly understand the criteria of patient selection.

Evaluation of Pupil Fields Using a Newly Developed Head-mounted Perimeter in Healthy Subjects

The purpose of this study was to evaluate the accuracy of pupil fields and determine the normative pupillary response data by age using a newly developed head-mounted perimeter. A total of 100 healthy subjects (age, 20 to 68 y) were enrolled. The newly developed head-mounted perimeter "imo" was used to measure the percentage pupil constriction (PPC) as response to a stimulus at all 36 test points of the visual field. Goldmann size III and V stimuli at 0, 8, and 11 decibels (dB) under 31.4, 6, and 3 apostilbs (asb) background were presented. The PPC correlations (r) of the right and left eyes were examined. Reproducibility was determined with the coefficient of variation (CV) and a Bland-Altman plot. By a simple bootstrap method, the mean PPC were analyzed as normative data in all 36 test points. Excellent correlation between both eyes was obtained for Goldmann size V stimuli, target luminance of 0 dB, and a background luminance of 31.4 asb (r=0.83; P<0.001). From the test-retest CV peripheral areas have low reproducibility compared with central areas. With a Goldmann size V target, there was a steeper decline of the PPC from the center field to the periphery field, and the temporal field PPC was larger than the nasal field. No major differences were observed between the PPC data and the age groups by decade (eg, center 3 degrees; P=0.223-0.913). Normative PPC data might well be useful for assessing objective visual fields with the newly developed head-mounted perimeter.

How fifth-grade pupils reason about fractions: a reliance on part-whole subconstructs

Fractions are an important part of the primary school mathematics curriculum, being introduced to children in the Slovenian educational system during the second grade (at age seven). For clarification of terms it is worth mentioning that the term “fraction” is only introduced in the sixth grade. Before that, the term “equal parts of a given whole” (In Slovene language, there are two different terms which are used in teaching about fractions: one is “equal parts of a given whole” as deli celote and another is “fraction” as ulomek. Fraction in our elementary school has the meaning of all other subconstructs proposed by Kieren (1976) except part-whole subconstruct. This subconstruct is covered by another term, namely “deli celote.” For easier understanding, we use in this paper only the term “fraction.”) is used. When we speak about “fractions” in primary school, we actually speak about parts of a given whole where the whole could be a set of objects or a single object that can be divided into equal parts. We used the fractional scheme theory for the theory framework of our research, focusing mainly on “parts within the whole,” the “part-whole” fraction scheme, and, to some extent, the “partitive unit” fraction scheme. Ninety fifth-grade pupils took a test we developed with the aim of achieving a better understanding of the field of pupils’ understanding of the part-whole aspect of fractions. More precisely, we were interested in how pupils understood the idea of dividing a whole into equal parts: is the idea of dividing mainly connected to dividing into congruent parts, are pupils able to reason about equal parts as parts of equal area, and do they adapt their reasoning according to the demands of the problems. The test consisted of four problems, each of them divided into parts (a total of eight problems to solve altogether). We used descriptive statistics and qualitative research based on the grounded theory method to process the data gathered from how participants solved the problems. We used the inductive process to determine how to categorize the responses and find relationship between the different categories. The findings showed that at the end of the fifth grade, pupils did not yet master the part-whole subconstruct of fractions and had problems related to linking congruency and parts of the whole. The mistakes pupils made clearly showed that a number of types of misunderstandings were prevalent: for example, not being able to connect the idea of fractions to equal parts of the whole or connecting the idea of fractions only to congruent parts of the whole as well as mistakes related to determining what part of the whole is presented.

Generation of a sub-half-wavelength focal spot with purely transverse spin angular momentum

We theoretically demonstrate that optical focus fields with purely transverse spin angular momentum (SAM) can be obtained when a kind of special incident fields is focused by a high numerical aperture (NA) aplanatic lens (AL). When the incident pupil fields are refracted by an AL, two transverse Cartesian components of the electric fields at the exit pupil plane do not have the same order of sinusoidal or cosinoidal components, resulting in zero longitudinal SAMs of the focal fields. An incident field satisfying above conditions is then proposed. Using the Richard–Wolf vectorial diffraction theory, the energy density and SAM density distributions of the tightly focused beam are calculated and the results clearly validate the proposed theory. In addition, a sub-half-wavelength focal spot with purely transverse SAM can be achieved and a flattop energy density distribution parallel to z-axis can be observed around the maximum energy density point.

Tightly focused optical field with controllable photonic spin orientation.

The spin angular momentum of photons offers a robust, scalable and high-bandwidth toolbox for many promising applications based upon spin-controlled manipulations of light. In this work, we develop a method to achieve controllable photonic spin orientation within a diffraction limited optical focal spot produced by a high numerical aperture objective lens. The required pupil field is found analytically through reversing the radiation patterns from two electric dipoles located at the focal point of the lens with orthogonal oscillation directions and quadrature phase. The calculated pupil fields are experimentally generated with a vectorial optical field generator. The produced photonic spin orientations are quantitatively evaluated by their spin densities according to the tightly focused electric fields calculated by Richard-Wolf vectorial diffraction theory to demonstrate the validity and capability of the proposed technique.

Experimental generation of complex optical fields for diffraction limited optical focus with purely transverse spin angular momentum.

We demonstrate a method to generate complex optical fields at the pupil plane of a high numerical aperture (NA) objective lens for the creation of diffraction limited optical focus with purely transverse spin angular momentum. The complex optical fields are analytically deduced through reversing the radiated patterns from two electric dipoles, which are located at the focal point of the high NA lens and oscillate respectively in x- and z- directions with phase difference of π/2. The derived fields can be experimentally created with a vectorial optical field generator. Using the Richard-Wolf vectorial diffraction theory, the electric fields within the focal region are calculated to evaluate the intensities and polarization distributions of the tightly focused beams corresponding to both the theoretical and experimentally generated pupil fields and the results clearly demonstrate the validity of the proposed technique.

Shaping the focal field of radially/azimuthally polarized phase vortex with Zernike polynomials

The focal field properties of radially/azimuthally polarized Zernike polynomials are studied. A method to design the pupil field in order to shape the focal field of radially or azimuthally polarized phase vortex is introduced. With this method, we are able to obtain a pupil field to achieve a longitudinally polarized hollow spot with a depth of focus up to and lateral resolution (FWHM) for an optical system with numerical aperture 0.99; a pupil field to generate eight focal spots along the optical axis is also obtained with this method.

Focused fields of given power with maximum longitudinal electric field component inside a substrate.

Closed formulas are presented for the electromagnetic field of given power in the lens pupil, which maximizes the longitudinal electric field when focusing through an interface at arbitrary depth along the optical axis. The optimum pupil field is found to be a continuous, monotonously increasing function of the radial pupil coordinate, which differs considerably from the commonly used annular illumination. Several cases of pupil fields and focused fields are shown for different materials, NA, and focusing depth. Also, the effect of absorbing media is considered.

James Webb Space Telescope segment phasing using differential optical transfer functions.

Differential optical transfer function (dOTF) is an image-based, noniterative wavefront sensing method that uses two star images with a single small change in the pupil. We describe two possible methods for introducing the required pupil modification to the James Webb Space Telescope, one using a small (<λ/4) displacement of a single segment's actuator and another that uses small misalignments of the NIRCam's filter wheel. While both methods should work with NIRCam, the actuator method will allow both MIRI and NIRISS to be used for segment phasing, which is a new functionality. Since the actuator method requires only small displacements, it should provide a fast and safe phasing alternative that reduces the mission risk and can be performed frequently for alignment monitoring and maintenance. Since a single actuator modification can be seen by all three cameras, it should be possible to calibrate the non-common-path aberrations between them. Large segment discontinuities can be measured using dOTFs in two filter bands. Using two images of a star field, aberrations along multiple lines of sight through the telescope can be measured simultaneously. Also, since dOTF gives the pupil field amplitude as well as the phase, it could provide a first approximation or constraint to the planned iterative phase retrieval algorithms.